阅读说明：本技术 可在增强发动机保护模式下操作的作业车辆发动机控制系统 (Work vehicle engine control system operable in enhanced engine protection mode ) 是由 斯科特·N·克拉克 于 2021-04-19 设计创作，主要内容包括：可在增强发动机保护(EP)模式下操作的作业车辆发动机控制系统以及相关联的方法和程序产品,包括存储器,该存储器存储第一默认功率曲线,该第一默认功率曲线具有如功率/速度图上所呈现的第一曲线形状,该功率/速度图分别沿竖直轴线和水平轴线绘制功率输出和发动机速度。控制器架构连接到存储器,并且可在增强EP模式下操作,其中控制器架构：(i)通过在如功率/速度图上所呈现的移动的EP上限之下重复拟合第一曲线形状来生成第一动态调节的功率曲线；(ii)利用第一动态调节的功率曲线来确定对应于作业车辆发动机的当前速度的功率输出目标(PO-(TAR))；以及(iii)根据功率输出目标(PO-(TAR))调度作业车辆发动机的功率输出。(A work vehicle engine control system operable in an enhanced Engine Protection (EP) mode, and associated methods and program products, includes a memory storing a first default power curve having a first curve shape as presented on a power/speed map plotting power output and engine speed along a vertical axis and a horizontal axis, respectively. A controller architecture connected to the memory and operable in an enhanced EP mode, wherein the controller architecture: (i) by using on e.g. power/speed diagramsRepeatedly fitting a first curve shape below the presented upper EP limit of the movement to generate a first dynamically adjusted power curve; (ii) determining a power output target (PO) corresponding to a current speed of a work vehicle engine using a first dynamically adjusted power curve TAR ) (ii) a And (iii) output target (PO) according to power TAR ) Power output of the work vehicle engine is scheduled.)

1. A work vehicle engine control system (22) for scheduling power output of a work vehicle engine (34) on a work vehicle (20), the work vehicle engine control system (22) comprising:

a memory (88), the memory (88) storing a first default power curve (96, 98) having a first curve shape as presented on a power/speed map (126, 142), the power/speed map (126, 142) including a vertical axis along which a power output of the work vehicle engine (34) increases in an upward direction and a horizontal axis along which an engine (34) speed increases in a rightward direction; and

a controller architecture (24), the controller architecture (24) connected to the memory (88) and operable in an enhanced Engine Protection (EP) mode in which the controller architecture (24):

generating a first dynamically adjusted power curve (128, 130) by repeatedly fitting the first curve shape below a moving upper engine protection limit (118) as presented on the power/speed map (126, 142);

determining a power output target (PO) corresponding to a current speed of the work vehicle engine (34) using the first dynamically adjusted power curve (128, 130)_TAR) (ii) a And

according to the power output target (PO)_TAR) Scheduling power output of the work vehicle engine (34).

2. The work vehicle engine control system (22) of claim 1, wherein said work vehicle (20) includes at least a first environmental sensor (74, 78, 80, 82), said first environmental sensor (74, 78, 80, 82) providing data indicative of an environmental parameter affecting combustion within said work vehicle engine (34); and is

Wherein the controller architecture (24) is further configured to repeatedly establish a current vertical position of the moving upper engine protection limit (118) as presented on the power/speed map (126, 142) using data provided by the first environmental sensors (74, 78, 80, 82).

3. The work vehicle engine control system (22) of claim 1, wherein the work vehicle (20) includes at least a first engine actuation device (72, 76, 84, 86) controllable to vary the amount of fuel or oxygen metered to the work vehicle engine (34) per combustion cycle; and is

Wherein the controller architecture (24) is configured to output the target (PO) when dependent on the power_TAR) Sending an actuation command to the first engine actuation device (72, 76, 84, 86) when scheduling power output of the work vehicle engine (34).

4. The work vehicle engine control system (22) of claim 1, wherein said first default power curve (96, 98) and said first dynamically adjusted power curve (128, 130) comprise a default power bump curve (98) and a dynamically adjusted power bump curve (128), respectively; and is

Wherein the controller architecture (24) is configured to determine the power output target (PO) using the dynamically adjusted power bump curve (128) at least in selected cases_TAR)。

5. The work vehicle engine control system (22) of claim 4, wherein the controller architecture (24) generally operates in a non-enhanced engine protection mode, and the controller architecture (24) is configured to transition from the non-enhanced engine protection mode to the enhanced engine protection mode when the moving engine protection upper limit (118) falls within a predetermined proximity of the default power bump curve (98) as presented on the power/speed map (126, 142).

6. The work vehicle engine control system (22) of claim 5, wherein the controller architecture (24) is configured to transition from the non-enhanced engine protection mode to the enhanced engine protection mode when the default power lobe curve (98) intersects the moving upper engine protection limit (118) due to a shift in a current vertical position of the moving upper engine protection limit (118) as presented on the power/speed map (126, 142).

7. The work vehicle engine control system (22) of claim 4, wherein the default power bump curve (98) has a curved shape with a negative slope that becomes increasingly larger as the engine (34) speed increases.

8. The work vehicle engine control system (22) of claim 4, wherein the work vehicle (20) has a power boost function;

wherein the memory (88) further stores a default power boost curve (96), the default power boost curve (96) having a second curve shape: and is

Wherein the controller architecture (24) is further configured to:

determining the power output target (PO) using the dynamically adjusted power bump curve (128) when the power boost function is turned off_TAR) (ii) a And

when the power boost function is engaged, (i) generating a dynamically adjusted power boost curve (130) by fitting the second curve shape below the moving engine protection upper limit (118) in its current vertical position as presented on the power/speed map (126, 142), and (ii) utilizing the dynamically adjusted power boost curve (130) to determine a power output target (PO) for scheduling power output of the work vehicle engine (34)_TAR)。

9. The work vehicle engine control system (22) of claim 8, wherein the work vehicle (20) comprises a combine having an unloading auger (44); and is

Wherein the controller architecture (24) is configured to automatically engage the power boost function when the discharge auger (44) is running.

10. The work vehicle engine control system (22) of claim 8, wherein the controller architecture (24) generates the dynamically adjusted power boost curve (130) to extend between the upper engine protection limit (118) and the dynamically adjusted power bump curve (128), as taken along a horizontal axis of the power/speed map (126, 142).

11. The work vehicle engine control system (22) of claim 1, wherein the controller architecture (24) is configured to generate the first dynamically adjusted power curve (128, 130) using a technique that includes shifting the first curve shape to fit below the moving engine protection upper limit (118) as presented on the power/speed map (126, 142).

12. The work vehicle engine control system (22) of claim 1, wherein the controller architecture (24) is configured to generate the first dynamically adjusted power curve (128, 130) using a technique that includes scaling the first curve shape to fit below the moving engine protection upper limit (118) as presented on the power/speed map (126, 142).

13. The work vehicle engine control system (22) of claim 1, wherein the controller architecture (24) is configured to generate the first dynamically adjusted power curve (128, 130) using techniques that include shifting and scaling the first curve shape to fit below the moving engine protection upper limit (118) as presented on the power/speed map (126, 142).

14. A work vehicle engine control system (22) for scheduling power output of a work vehicle engine (34) on a work vehicle (20), the work vehicle (20) having a power boost function, the work vehicle engine control system (22) comprising:

a memory (88), the memory (88) storing:

a default power lobe curve (98), the default power lobe curve (98) having a first curve shape as presented on a power/speed map (126, 142), the power/speed map (126, 142) including a vertical axis along which a power output of the work vehicle engine (34) increases in an upward direction and a horizontal axis along which an engine (34) speed increases in a rightward direction; and

a default power boost curve (96), the default power boost curve (96) having a second curve shape as presented on the power/speed map (126, 142);

a controller architecture (24) connected to the memory (88) and operable in an enhanced Engine Protection (EP) mode in which the controller architecture (24):

if the power boost function is turned off: (i) generating a dynamically adjusted power bump curve (128) by repeatedly fitting the first curve shape under a moving upper engine protection limit (118) as presented on the power/speed map (126, 142), and (ii) determining a power output target (PO) corresponding to a current speed of the work vehicle engine (34) using the dynamically adjusted power bump curve (128)_TAR)；

If the power boost function is engaged: (i) generating a dynamically adjusted power boost curve (130) by repeatedly fitting the second curve shape below the moving upper engine protection limit (118), and (ii) determining a power output target (PO) corresponding to the current speed of the work vehicle engine (34) using the dynamically adjusted power boost curve (130)_TAR) (ii) a And

according to the power output target (PO)_TAR) Scheduling power output of the work vehicle engine (34).

15. The work vehicle engine control system (22) of claim 14, wherein the work vehicle (20) comprises a combine having an unloading auger (44); and is

Wherein the controller architecture (24) is configured to automatically engage the power boost function when the discharge auger (44) is running.

Technical Field

The present disclosure relates to work vehicle engine control systems operable in an enhanced engine protection mode, and to related methods and program products.

Background

Modern work vehicles are typically equipped with an engine control system for controlling the engine according to factory programmed characteristics or curves (referred to herein as "engine control curves")A "power bump curve") to schedule engine power output. Such engine control systems may monitor the output speed of the work vehicle engine; also, for a given output speed, the current output speed of the engine is converted to the desired power output of the engine (herein, either "power output target" or "PO") using the power lobe curve_TAR"). The engine control system may then command certain actuated devices to match the power output of the engine to the PO to the extent allowed by the real world operating conditions_TARAligned or coincident. The logic of the engine control system may be executed by a controller associated with operating the vehicle engine, such as an Engine Control Unit (ECU). The actuated devices used by the engine control system to vary engine power output vary from engine platform to engine platform, but typically include one or more devices that control the amount of fuel and oxygen (as determined by air volume, density and temperature) delivered to the engine combustion chambers per combustion cycle. By adjusting the engine power output of the work vehicle engine in this manner, the engine control system may provide a predictable, reliable operating experience for the work vehicle operator while maintaining the ability to rapidly increase the engine power output as needed in most operating scenarios encountered by the work vehicle.

Disclosure of Invention

An operating vehicle engine control system operable in an enhanced Engine Protection (EP) mode is provided. In an embodiment, a work vehicle engine control system includes a memory storing a first default power curve having a first curve shape as presented on a power/speed map. The power/speed map includes a vertical axis along which the power output of the work vehicle engine increases in an upward direction and a horizontal axis along which the engine speed increases in a rightward direction. The controller architecture is connected to the memory and is operable in an enhanced EP mode in which the controller architecture: (i) by fitting the first repeatedly under the EP upper bound of the movement as presented on the power/velocity diagramGenerating a first dynamically adjusted power curve by a curve shape; (ii) determining a power output target (PO) corresponding to a current speed of a work vehicle engine using a first dynamically adjusted power curve_TAR) (ii) a And (iii) outputting the target (PO) according to the power_TAR) Power output of the work vehicle engine is scheduled.

In further embodiments, a work vehicle engine control system includes a memory and a controller architecture connected to the memory and operable in an enhanced EP mode. The memory stores a default power bump curve having a first curve shape as presented on the power/speed map. The power/speed map includes a vertical axis along which the power output of the work vehicle engine increases in an upward direction and a horizontal axis along which the engine speed increases in a rightward direction. The memory stores a default power boost curve having a second curve shape as presented on the power/speed map. When placed in enhanced EP mode and the power boost function of the work vehicle is turned off, the controller architecture: (i) generating a dynamically adjusted power bump curve by repeatedly fitting the first curve shape below an upper EP limit of movement as presented on the power/velocity graph; and (ii) determining a power output target (PO) corresponding to a current speed of the work vehicle engine using the dynamically adjusted power lobe curve_TAR). In contrast, when placed in enhanced EP mode and the power boost function of the work vehicle is engaged, the controller architecture: (i) generating a dynamically adjusted power boost curve by repeatedly fitting a second curve shape below the moving upper EP limit; and (ii) determining a power output target (PO) corresponding to the current speed of the work vehicle engine using the dynamically adjusted power boost curve_TAR). Whether the power boost function is engaged or disengaged, the controller architecture then outputs a target (PO) according to the power_TAR) Power output of the work vehicle engine is scheduled.

Methods and program products associated with a work vehicle engine control system operable in an EP mode are also provided. In this respect, also disclose a and operation carWork vehicle program products for use in conjunction with vehicle engine control systems. The work vehicle engine control system includes a controller architecture operable in an enhanced EP mode and located on a work vehicle having a work vehicle engine. In various embodiments, the work vehicle program product includes a non-transitory computer readable medium. A first default power curve is stored in the non-transitory computer readable medium and has a first curve shape as presented on a power/speed map that includes a horizontal axis along which engine speed increases in a rightward direction and a vertical axis along which power output increases in an upward direction. Computer readable instructions are also stored on the computer readable medium. When executed by the controller architecture while the work vehicle engine control system is placed in the enhanced EP mode, the computer readable instructions cause the controller architecture to: (i) generating a first dynamically adjusted power curve by fitting a first curve shape below an upper EP limit that intersects the first default power curve as presented on the power/speed graph, the first dynamically adjusted power curve having a curved shape that decreases in slope as engine speed increases; (ii) determining a power output target (PO) corresponding to a current speed of a work vehicle engine using a first dynamically adjusted power curve_TAR) (ii) a And (iii) output target (PO) according to power_TAR) Power output of the work vehicle engine is scheduled.

The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features and advantages will become apparent from the description, the drawings, and the claims.

Drawings

At least one example of the disclosure will be described below in conjunction with the following figures:

FIG. 1 is a schematic illustration of a work vehicle, here a combine harvester, equipped with a work vehicle engine control system operable in an enhanced Engine Protection (EP) mode, according to an exemplary embodiment of the present disclosure;

FIG. 2 is a power/speed plot of engine power output (plotted along the ordinate or vertical axis of the plot) versus engine speed (plotted along the abscissa or horizontal axis) illustrating a default power lobe curve and a default boost curve that may be selectively used to schedule engine power output under standard operating (non-EP-constrained) conditions;

FIG. 3 is a power/speed plot of engine power output (vertical axis) versus engine speed (horizontal axis) illustrating a conventional method of imposing an upper EP limit on a default power bump curve (FIG. 2) under EP constraints while the default power boost curve is rendered unavailable;

fig. 4 and 5 are power/speed diagrams illustrating an example manner in which the work vehicle engine control system of fig. 1 may generate a dynamically adjusted power curve by shifting (translating) to fit a corresponding default curve shape below an upper EP limit when the engine control system is operating in an enhanced EP mode;

FIG. 6 is a power/speed diagram illustrating an example manner in which the work vehicle engine control system of FIG. 1 may generate a dynamically adjusted power curve by fitting a corresponding default curve shape below an upper limit of EP in conjunction with shifting (translating) and scaling (compressing) when the engine control system is operating in an enhanced EP mode; and

fig. 7 is a flowchart illustrating an EP enhancement process suitably carried out by the controller architecture of a work vehicle engine control system (fig. 1) when operating in an enhanced EP mode of an exemplary embodiment of the present disclosure.

Like reference symbols in the various drawings indicate like elements. For simplicity and clarity of illustration, descriptions and details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the exemplary and non-limiting embodiments of the invention described in the following detailed description. It should also be understood that, unless otherwise indicated, features or elements appearing in the figures are not necessarily drawn to scale.

Detailed Description

Embodiments of the present disclosure are illustrated in the figures that are briefly described above. Various modifications to the exemplary embodiments may be envisaged by those skilled in the art without departing from the scope of the invention, as set out in the appended claims.

As presented herein, the term "fit below … …" as used in reference to a relationship between a first curve and a second curve (or point) indicates that the shape of the first curve does not rise above the second curve (or point) when described as "fit below the second curve (or point)", as presented on a power/speed map of the type described below. Thus, continuing this example, the term "fit below … …" does not exclude the possibility that the first curve overlaps or coincides with the second curve (or point) at one or more locations on the power/velocity map. Further, the term "Engine Protection (EP) upper limit" refers to a curve or point to which the dynamically adjusted power curve described below should not rise when the work vehicle engine control system is operating in the EP mode. The dynamically adjusted power curve may be adjusted (by graphical shifting (panning), scaling (compressing), or a combination thereof) in conjunction with a power-wise movement of the EP upper limit (corresponding to a vertical shift of the EP upper limit on the power/speed map) to ensure that the maximum power output value (or values) of the given dynamically adjusted power curve does not exceed the maximum allowable power output value set by the EP upper limit, as discussed in detail below.

SUMMARY

As noted above, modern work vehicles are typically equipped with an engine control system for scheduling engine power output according to factory programmed characteristics or curves. When presented on a power/speed graph plotting output power and engine speed along the vertical and horizontal axes, respectively, the factory-programmed curve may have a generally curved shape that decreases in slope (e.g., has an increasingly negative slope) as engine speed increases. For this reason, this factory programmed characteristic is referred to herein as the "default power bump curve". As presented on such a power/speed map, the default power bump curve has a fixed position and, therefore, spans a fixed power range and a fixed speed range on the power/speed map. The power output values of the default power bump curve (and other curves discussed herein) may be described in kilowatts (kW), while the engine speed values are described in Revolutions Per Minute (RPM).

In some cases, the work vehicle may also provide a power boost function that may be engaged to temporarily increase the power output of the work vehicle engine. Such a power boost function may help to accommodate significant transient loads or "parasitics" imposed on the work vehicle engine due to activation of a power demand function, such as assistance of the work vehicle. As a first example (which will be discussed in detail below), the combine may have a power boost function that is automatically engaged when the discharge auger is activated to discharge grain from the clean grain bin of the harvester during forward travel of the combine. As a second example, a tractor equipped with a Power Take Off (PTO) may have a power take off function that is engaged opportunistically when the PTO shaft drives a power requiring implement (such as a baler) that is towed by the tractor. When the power boost function of a particular work vehicle is engaged, the engine control system may transition from scheduling engine power output according to the default power boost curve mentioned above to scheduling engine power output according to a secondary curve referred to herein as the "default power boost curve". The default power boost curve provides an increased or boosted power output target (PO) for a given output speed of the work vehicle engine relative to the default power bump curve_TAR) To accommodate temporary increases in engine load. When the power boost function is subsequently turned off, the engine control system may then revert to scheduling engine power output according to the default power bump curve.

The engine scheduling scheme described above works well under most operating conditions encountered by a work vehicle. However, using such conventional engine scheduling schemes can be problematic where environmental extremes greatly impair the combustion efficiency of the work vehicle engine. Under such environmental conditions, scheduling engine power output according to the default power bump curve or the default power boost curve may result in increased wear and potential damage to the work vehicle engine. Such conditions, referred to herein as "Engine Protection (EP) constraints," typically reduce the combustion efficiency of the work vehicle engine due to the reduction in the amount of combustible oxygen content per volume of air that occurs at higher altitudes (lower atmospheric pressures) and at elevated ambient temperatures. For this reason, certain engine control systems are now configured to operate in a dedicated mode (referred to herein as the "EP mode") to protect the work vehicle engine from potential damage under EP constraints.

When operating in the EP mode, the work vehicle engine control system imposes an artificial limit on the power output of the work vehicle engine. This limit is referred to as the "EP upper limit" and may be graphically represented as a curve or characteristic of a power/speed map. In general, the EP upper limit may be expressed as a relatively simple function, such as a linear function having a flat (zero) slope or a small negative slope, as further shown and discussed below in connection with fig. 2-6. The vertical (power-wise) position of the EP upper limit is not fixed on the power/speed map, but moves with changing EP constraints, as compared to the default power boost curve and the default power bump curve. Generally, as the combustion efficiency of the work vehicle engine is further suppressed (e.g., due to increased ambient temperature or reduced atmospheric pressure at higher elevations), the EP upper limit is shifted vertically downward (a decrease in power range) and intersects lower and lower portions of the default power lobe curve. Scheduling a higher power output target (PO) for a given engine speed at a default power boost curve_TAR) Without imposing an upper EP limit that covers the default power boost curve and schedules a reduced power output target (PO) for a given engine speed_TAR). In doing so, the EP upper limit protects the work vehicle engine from potential damage while providing the maximum power output allowed under current EP constraints. As a corollary, the work vehicle's power boost function (if otherwise mentioned)Where provided) are rendered unusable under EP constraints.

While beneficial from an engine protection perspective, the above-described method of imposing an upper EP limit under EP constraints is limited in several respects. First, imposing an EP upper limit on the default power bump curve fundamentally alters the responsiveness and behavior of the work vehicle engine under EP limiting conditions. Such changes in engine behavior are observable by work vehicle operators, particularly when such operators are typically very accustomed and familiar with engine behavior when scheduling according to a default power bump curve. Engine behavior may thus become inconsistent with operator expectations when the engine control system is operating in the EP mode, with a corresponding degradation in operator satisfaction. Further, it has traditionally been considered desirable (and conventional EP scheduling schemes therefore sought) to provide the operator with the maximum or peak engine power output allowed under a given set of EP constraints, particularly when the scheduled engine power output has decreased compared to that provided under standard (non-EP) operating conditions. Surprisingly, however, this premise is determined to be false or erroneous for most work vehicle operators. In contrast, conventional practice of providing the operator with maximum engine power output (again, as permitted by the upper EP limit under EP limiting conditions) has been found to have several negative consequences, including compromising overall drivability of the work vehicle, encouraging undesirable driving behavior, reducing work vehicle productivity, and further reducing operator satisfaction levels. Finally, a reduction in operator satisfaction level and work vehicle efficiency is also observed due to the unavailability of the power boost function (if provided normally) under the EP constraints.

The following describes work vehicle engine control systems that overcome many, if not all, of the limitations described above associated with conventional engine control systems when operating under EP constraints. Such work vehicle engine control systems operate in an improved or enhanced mode under EP constraints; the term "enhanced EP mode" as it appears herein refers to an operating mode that is activated under EP constraints, wherein the work vehicle engine control system generates at least one dynamically adjusted power curve for use in scheduling engine power output. For example, in an embodiment, a work vehicle engine control system (or more specifically, a processing subsystem or "controller architecture" included in the engine control system) may generate a dynamically adjusted power bump curve, and possibly at least one dynamically adjusted power boost curve. As indicated by the narrative term "dynamically adjusted," the dynamically adjusted power curve(s) are adjusted or modified on an iterative basis by the work vehicle engine control system in response to movement of the EP upper limit. Specifically, as the EP upper limit moves in a direction in power (corresponding to a vertical direction on the power/speed map), the controller architecture of the engine control system iteratively adjusts or modifies (also referred to herein as repeatedly "generating" or "building") the dynamically adjusted power curve(s) to fit below the moving EP upper limit. In the case of the enhanced EP mode, the EP upper limit may be represented on the power/speed map as a curve or characteristic, as discussed in detail below; or the EP upper limit may be expressed as a single value indicative of the maximum allowable power output above which the maximum power output value (or values) of the dynamically adjusted power curve should not rise.

The controller architecture may generate a dynamically adjusted power curve by fitting the shape of the corresponding default power curve(s) below the moving EP upper limit using techniques involving shifting (panning), scaling (compression), or a combination thereof. For example, consider an embodiment in which the controller architecture generates a dynamically adjusted power bump curve by fitting the curve shape of the default power bump curve below the upper EP limit, here by vertical translation or shift only. The peak or maximum power output value of the dynamically adjusted power bump curve may be located at or immediately below the upper EP limit. In such embodiments, the dynamically adjusted power bump curve is generated to have a shape that matches the shape of the default power bump curve, while also having a variable vertical (in terms of power) position as presented on the power/speed map that is repeatedly modified by the controller architecture to keep the dynamically adjusted power bump curve below the moving EP upper limit. In contrast, in embodiments where the controller architecture applies scaling (in addition to or instead of shifting) to keep the dynamically adjusted power bump curve below the EP upper limit of movement, the shape of the dynamically adjusted power bump curve may be essentially a vertically compressed version of the curved shape of the default power bump curve as presented on the power/speed map. Similarly, in an embodiment, the controller architecture of the engine control system may likewise be shifted (translated), scaled (compressed), or a combination thereof to fit the curve shape of the default power boost curve below the upper EP limit of the shift to generate a dynamically adjusted power boost curve.

Operation of a work vehicle engine control system in an enhanced EP mode of the type described herein provides several significant advantages. First, because the shape of the default power boost curve is typically preserved (although compressed in some cases), the behavior of the work vehicle engine under EP constraints is made more consistent or coordinated with the behavior of the work vehicle engine under standard operating (non-EP constraints) conditions. Thus, the behavior of the work vehicle engine under the EP constraints more closely matches the operator expectations to improve the overall operator satisfaction level. Here, it can be observed that using a dynamically adjusted power bump curve (rather than conventionally using an EP upper limit) to schedule engine power output results in a lower engine output being scheduled than would otherwise be scheduled under EP operating conditions (which has reduced engine output to avoid engine damage, as previously discussed). Counter to intuition, it has been found that by generally maintaining the shape of the default power convex curve, the operator's level of satisfaction is improved, and thus the operator's customary behavior of the work vehicle engine is extended to EP restriction conditions (albeit at reduced power output levels), as just mentioned. Additionally, the practice of utilizing a dynamically adjusted power lobe curve to schedule engine output power (such that the maximum allowable power output is not typically provided at a given engine speed under EP conditions) has the benefit of opening a vertical (in terms of power) gap or bandwidth between the dynamically adjusted power lobe curve and the EP upper limit. This newly acquired power bandwidth encourages good driving behavior for the benefit of the work vehicle operator and also improves the overall drivability of the work vehicle for reasons discussed below. Finally, as an additional benefit in embodiments where the engine control system generates a dynamically adjusted power boost curve in addition to a dynamically adjusted power bump curve, the power boost function of the work vehicle (when applicable) may be preserved under the EP constraints to bring additional improvements in work vehicle efficiency and operator satisfaction levels.

An exemplary embodiment of a work vehicle engine control system will now be described in conjunction with fig. 1-7. Specifically, an exemplary work vehicle (herein a combine) equipped with a work vehicle engine control system is described below in conjunction with fig. 1, while exemplary processes that may be implemented by embodiments of the engine control system are described below in conjunction with fig. 2, 3, and 5-7. While the following discussion focuses on a particular type of work vehicle, it is emphasized that embodiments of the engine control system may be advantageously incorporated into various types of work vehicles operating under EP constraints, including work vehicles employed in the agricultural, mining, forestry, and construction industries.

Example work vehicle Engine control System operable in enhanced EP mode

Referring initially to fig. 1, an exemplary work vehicle (here, an agricultural combine or "combine" 20) equipped with an exemplary engine control system 22 is presented. As described more fully below, exemplary work vehicle engine control system 22 includes a processing subsystem or "controller architecture" 24 operable in an enhanced EP mode. Work vehicle engine control system 22 typically operates in a standard operating mode and transitions to an enhanced EP mode in response to detection of an EP constraint. Operation of work vehicle engine control system 22 in the enhanced EP mode is discussed below in conjunction with fig. 2-7. However, combine 20 is first described in more detail to establish a non-limiting, exemplary environment in which embodiments of work vehicle engine control system 22 may be better understood.

In addition to the work vehicle engine control system 22, the combine 20 includes a main body or chassis 26, a cab 28 located at or adjacent a front portion of the chassis 26, and an operator station enclosed by the cab 28. The harvester chassis 26 is supported by a plurality of ground engaging wheels 30. The wheels 30 of the work harvester chassis 26 are driven by a power system 32 that includes a work vehicle engine 34, an example of which is shown in greater detail in the lower right region of fig. 1. A standard header or grain platform 36 is mounted to a feedwell 38 that extends from the forward end of the combine 20 in a forward direction. As the combine harvester 20 travels over the field 40, crop plants are cut by the grain platform 36, brought into the feeding chamber 38, and processed in subsequent portions of the harvester 20. The net grain is conveyed to the net grain bin 42 by a net grain elevator, not shown, contained within a central portion of the combine harvester 20. The net grain collected in the net grain bin 42 may be unloaded from the combine 20 using the unloading auger 44, possibly while the combine continues to travel in a forward direction over the field 40. During unloading of the clean grain, the unloading auger 44 is driven by the work vehicle engine 34 through a mechanical connection not shown.

In the example of FIG. 1, work vehicle engine 34 takes the form of a heavy duty diesel engine that includes an Exhaust Gas Recirculation (EGR) system 46. In other embodiments, work vehicle engine 34 may take different forms, such as a non-diesel internal combustion engine or a diesel engine lacking an EGR system, depending on the particular type of work vehicle in which work vehicle engine 34 is installed. The particular equipment used by engine control system 22 to vary the power output of work vehicle engine 34 will also vary depending on the engine platform and physical engine characteristics in question. In this regard, various mechanisms and techniques for controlling the power output of a work vehicle engine are well known in the relevant industries. Accordingly, the following description of specific ways in which engine control system 22 may modify the power output of work vehicle engine 34 during operation of combine 20 should be understood to be merely illustrative or exemplary.

When provided, EGR system 46 may reduce nitrous oxide (NOx) and other pollutants in exhaust gases generated during operation of work vehicle engine 34. In the illustrated example, the EGR system 46 includes a gas inlet duct 48, the gas inlet duct 48 supplying ambient air to an inlet of a waste-gated turbocharger (WGT) 50. The WGT 50 discharges compressed air through a first conduit to an air-to-air cooler section 52. The second conduit draws exhaust gas from an engine core 54 of the work vehicle engine 34, which is cooled with an EGR cooler 56. Control valve 58 is positioned in flow series with (e.g., downstream of) EGR cooler 56 to regulate the flow of exhaust therethrough. After passing through the control valve 58, the cooled exhaust gas mixes with the relatively cool airflow provided by the air-to-air cooler section 52 within the bifurcated conduit 60. The bifurcated conduit 60 then directs the exhaust-air mixture into the intake manifold of the engine core 54. Thus, the exhaust temperature is reduced while the oxygen content in the exhaust-air mixture is optimized. Where further emission control is sought, EGR system 46 may also include components that support Selective Catalytic Reduction (SCR) of particulate matter entrained in the exhaust. In this regard, exhaust gas may be received from the engine core 54, directed through a conduit 62, and into a Diesel Oxidation Catalyst (DOC) chamber 64 for contact with a suitable catalyst. An exhaust throttle 66 may be positioned in conduit 62 to regulate the flow of exhaust gas to DOC chamber 64. The treated exhaust from the DOC chamber 64 then flows to a reaction chamber, not shown, where the desired SRC reaction occurs before the exhaust is discharged from the combine 20.

In addition to the EGR system 46 described above, work vehicle engine 34 contains various other components that are typically integrated into a work vehicle engine or powertrain. These components may include fuel injectors, not shown, and a Fuel Metering Unit (FMU) 68 fluidly connected to the fuel injectors. Specifically, the FMU 68 is positioned upstream of the fuel injectors; and, as indicated by arrow 70, the liquid fuel drawn from the fuel tank on the combine 20 is metered before the metered fuel is delivered to the fuel injector for spray delivery to the engine combustion chamber. In embodiments, the FMU 68 may include or cooperate with a metered high pressure pump (e.g., an axial piston pump) to provide this functionality. Additionally, FMU 68 may incorporate a valve element (e.g., a translating spool) that may be positioned using a valve actuation member included in a plurality of actuated devices 72 to control the power output of work vehicle engine 34, as discussed more fully below. Similarly, either or both of valves 58, 66 included in EGR system 46 may be modulated by corresponding valve actuators, which may be included in actuated device 72 in embodiments of work vehicle engine control system 22.

In addition to the above-mentioned actuated devices 76 and controller architecture 24, exemplary work vehicle engine control system 22 also includes one or more environmental sensors 74. Environmental sensors 74 included in work vehicle engine control system 22 may include sensors for monitoring any environmental parameters that affect combustion within engine 34 (e.g., any environmental parameters that affect the oxygen content supplied to the combustion chambers of work vehicle engine 34 per combustion cycle). Such environmental parameters may include the current ambient temperature measured by one or more air temperature sensors 78; local atmospheric pressure measured directly by pressure sensor(s) 80 or inferred by sensors providing data indicative of altitude; or any other sensor 82 that measures a similar parameter that affects combustion within the combustion chamber of work vehicle engine 34.

As further included in work vehicle engine control system 22, actuated devices 76 may include any number and type of devices capable of controllably affecting the power output of work vehicle engine 34. Generally, such actuated devices 76 will affect engine output by changing at least one parameter that affects: (i) one or more characteristics of air drawn into a combustion chamber of work vehicle engine 34 (e.g., oxygen content, density, volume, and/or temperature), and/or (ii) a volume of fuel injected into the combustion chamber per combustion cycle. In this latter aspect, and as indicated above, actuated device 76 may include one or more fuel metering actuators 72 that may vary the rate or schedule of metered fuel supplied to the fuel injectors of work vehicle engine 34 via metering valve modulation. Additionally or alternatively, actuated device 76 may include an EGR valve actuator 84 that affects the extent to which cooled exhaust gas is recirculated to the combustion chambers of work vehicle engine 34, or otherwise affects the oxygen content (and temperature) of the air/exhaust gas mixture ultimately supplied to the combustion chambers. Finally, actuated devices 76 may include any other type of actuated device capable of substantially changing the power output of work vehicle engine 34 in response to commands received from controller architecture 24.

Describing the controller architecture 24 in more detail, the controller architecture 24 is associated with the computer-readable memory 88 and may communicate with the various illustrated components via wired data connections, wireless data connections, or any combination thereof; for example, the controller architecture 24 may communicate with many or all of the illustrated components over a vehicle bus, such as a Controller Area Network (CAN) bus. The term "controller architecture" appearing throughout this document is used in a non-limiting sense to refer generally to the processing architecture of work vehicle engine control system 22 (or other work vehicle engine control system). The controller architecture 24 may encompass or may be associated with any practical number of processors, individual controllers, computer-readable memory, power supplies, storage devices, interface cards, and other standardized components. The controller architecture 24 may also include or cooperate with any number of firmware and software programs or computer-readable instructions designed to perform the various process tasks, calculations, and control functions described herein. Such computer readable instructions may be stored in a non-volatile sector of memory 88 associated with (accessible to) controller architecture 24. Although shown generally as a single block in FIG. 1, memory 88 may encompass any number and type of storage media suitable for storing computer readable code or instructions, as well as other data for supporting the operation of engine control system 22. In an embodiment, the memory 88 may be integrated into the controller architecture 24, for example, as a system-in-package, a system-on-chip, or another type of microelectronic package or module.

The memory 88 also stores a power curve database 90 containing at least one default power curve. In the illustrated example, in particular, the power curve database 90 contains at least a default power bump curve and a default power boost curve. More specifically, memory 88 may contain data from which the shape and fixed location of the default power bump curve and default power boost curve as presented on a power/speed map of the type described below may be determined. Such a curve may be stored as a single function (e.g., see default power bump curve 98 discussed below), as multiple functions as appropriate (e.g., see default power boost curve 96 discussed below), as a collection of power speed values, as start and end point coordinates when a particular curve is a linear (straight line) function, or using any other suitable data structure, as appropriate. The power curve database 90 may also contain data defining aspects of the EP upper bound (e.g., the slope of the EP upper bound if in the form of a linear function with a non-zero slope, as described below), as well as other data that may be useful in performing the processes described below in connection with fig. 2-7.

Referring now to fig. 2, a power/speed graph 94 plotting an exemplary default power bump curve 98 and an exemplary default power boost curve 96 is shown. The engine power output is plotted along the vertical axis of the power/speed map 94 and may be expressed in kW as calculated using the torque presented on the engine output shaft multiplied by the time component. At this pointIn this regard, it will be understood that all discussions herein relating to power output versus engine speed of a work vehicle engine (e.g., work vehicle engine 34) may be readily converted to an output torque versus engine speed curve (if so desired) for the various curves described throughout this disclosure without departing from the scope of the present disclosure. With the power/speed map 94 shown, the engine power output range is plotted from a minimum power output (P)_min) Extending to maximum power output (P)_max)。P_minAnd P_maxThe specific values of (a) will vary between the embodiment and the engine platform, but in one non-limiting embodiment may be approximately 170 + -50 kW and 190 + -50 kW, respectively. In contrast, engine speed is plotted along the horizontal axis of the power/speed graph 94, in RPM, and from a first value (R) over the plotted range_min) Extending to a second value (R)_max). Likewise, R_minAnd R_maxWill vary between embodiments, but in one non-limiting example may be 1700 ± 100RPM and 1900 ± 100RPM, respectively.

As presented herein, the term "curve" refers to a characteristic or trajectory that may be graphically represented on a two-dimensional power versus speed (or torque versus speed) graph, such as the exemplary power/speed graph 94 shown in fig. 2, where the curve has a single power (or torque) value for each speed value over the length of the curve. Thus, in embodiments, a given curve may have any shape, whether it is a shape of a curve (see, by way of example, default power bump curve 98), a shape of a linear (straight line) function, a shape of a piecewise function (see, by way of example, default power boost curve 96), or a more complex (e.g., W-shaped) geometry. As described above, a particular curve may be stored in memory 88 as a function, as multiple functions (if the curve is segmented or made up of multiple distinct segments), as a set of coordinates, or in any other suitable manner.

As graphically depicted in FIG. 2, the default power bump curve 98 represents a factory build for scheduling engine power output under standard operating (non-EP constraint) conditionsAnd (4) a course curve. The default power bump curve 98 is referred to as a "power bump curve" when moving from its illustrated starting point 100 to its illustrated ending point 102, particularly over a middle region 103 of the curve 98, with reference to the relatively pronounced curvature or downward slope followed by the curve 96. Herein, the terms "start point shown" and "end point shown" are used to indicate that the default power bump curve 98 may extend beyond the illustrated segment of interest shown in FIG. 2 to some extent, although any extension of the default power bump curve 98 beyond the end point 102 shown is generally nominal; this also applies to the other curves discussed herein. Thus, the default power bump curve 98 (at least the portion shown in fig. 2) may be described as having a curved shape with a non-positive slope throughout or substantially throughout, wherein the slope of the curve 96 gradually becomes negative (following a gradually steeper decline) moving from the shown starting point 100 to the shown end point 102. Thus, proceeding from the illustrated start point 100 of the default power bump curve 98 toward the illustrated end point 102, a relatively large change in engine speed will be near S_minProduces relatively little change in the scheduled engine power output at lower PMs. In contrast, in the vicinity of S_maxAt higher RPMs, relatively small changes in engine speed will result in relatively significant changes in the scheduled engine power output. The position of the default power bump curve 98 is fixed such that the power range spanned by the curve 98 is unchanged, as is the default power boost curve 96 described below.

As further depicted on the power/speed graph 94 (FIG. 2), the default power boost curve 96 represents a factory programmed power curve over which the engine output power is increased or "boosted" for a given speed range. Thus, the power output value for each speed value within the range of the default power boost curve 96 may be greater than the power output value for the same speed value of the default power bump curve 98. Further, the difference in power output values of the default power boost curve 96 generally increases as one moves from the illustrated start point 104 to the illustrated end point 106 of the curve 98, as illustrated by the double arrow 108 in fig. 2. As briefly noted above, in the illustrated example, the default power boost curve 98 has a piecewise geometry; here, the angled two-segment structure is made up of a first segment 110 and a second segment 112, wherein the first segment 110 takes the form of a segment having a first constant negative slope, and the second segment 112 similarly takes the form of a segment having a second constant negative slope that is less (steeper) than the first constant negative slope. In other embodiments, the default power boost curve 96 may have a more basic shape (e.g., the shape of a single line segment or a gently curved line) or a more complex shape, such as a piecewise function having three or more segments or sections.

When applicable, default power boost profile 96 may be used in the context of a work vehicle having a power boost function that is selectively engaged in response to certain conditions, due to operator commands, and/or automatically (i.e., without operator input). In this latter aspect, controller architecture 24 (which may consist of or include an ECU) may automatically engage the power boost function (and thus schedule engine power output under normal (non-EP) operating conditions according to default power boost curve 96) when the auxiliary functions impose substantial additional loads or parasitic effects on work vehicle engine 34. For example, in the case of the combine harvester 20, the controller architecture 24 may automatically engage the power boost function during unloading of harvested grain from the net grain tank 42 of the combine harvester 20 using the unloading auger 44. In other embodiments, the host work vehicle may not have such power boost functionality, in which case the default power boost profile may not be stored in memory 88 or otherwise used. In further embodiments, a plurality of default power boost curves may also be stored (and a plurality of dynamically adjusted power boost curves, as described below, generated) to provide a series of curves for selection based on the severity of the parasitic load imposed on work vehicle engine 34 at a given time.

As previously discussed, the engine scheduling scheme described above works well under standard operating conditions. However, inScheduling engine power output according to default power bump curve 98, and in particular according to default power boost curve 96, under non-standard operating conditions, such as EP constraints, may result in rapid wear and potential damage to work vehicle engine 34. Such non-standard operating conditions or "EP constraints" may occur when the ambient temperature becomes very high and/or the work vehicle is operating at higher altitude (low atmospheric pressure) conditions. When such EP constraints occur, particularly when such conditions occur in combination, operation of work vehicle engine 34 according to either of curves 96, 98 may result in accelerated engine wear and potential damage, particularly when work vehicle engine 23 is near S as compared to S_maxIs closer to S_minAt lower engine speeds. For this reason, certain manufacturers impose protective countermeasures, referred to as EP measures, under such EP constraints, as briefly discussed above and in more detail below in connection with fig. 3. In one non-limiting example, operation of the work vehicle at temperatures in excess of about 35 degrees celsius and heights in excess of about 1600 meters altitude may be sufficient to trigger operation of the engine control system in the EP mode. In other cases, different values of these parameters (considered in combination or individually) may be sufficient to trigger EP mode operation.

Turning now to fig. 3, a power/speed diagram 114 is presented to generally illustrate one manner in which EP protection may be applied under EP constraints in accordance with conventional methods. For consistency of explanation, the default power boost curve 96 is moved from fig. 2, although it will be appreciated that the upper dashed portion 116 of the default power boost curve 96 is operationally eliminated or rendered unusable in the exemplary scenario of fig. 3 for reasons explained below. In contrast, the default power boost curve 96 is not shown on the power/speed map 114 because the power boost function is completely disabled or rendered unavailable when the engine control system is operating in the conventional EP mode. In this example, an EP upper limit curve 118 has been superimposed onto the power/speed map 114 at a location that intersects the default power boost curve 96. The EP upper limit curve 118 (hereinafter referred to simply as "EP upper limit 118") has a substantially linear geometry in the example shown, and may extend completely horizontally (zero slope), or alternatively have a slight negative slope as shown. In other cases, the EP upper limit 118 may have a different shape or orientation. In contrast to the default power bump curve 98, the location of the EP upper limit 118 is not fixed on the power/speed map 114, but may move vertically (in power) as the EP constraints change. In an embodiment, controller architecture 24 determines the vertical positioning of EP upper limit 118 from sensor data (such as sensor data received from environmental sensors 74) indicative of environmental parameters affecting combustion within work vehicle engine 34, such as current ambient temperature and ambient air characteristics (e.g., local atmospheric pressure, whether directly measured or inferred from altitude). Generally, when combustion efficiency is suppressed by these parameters (e.g., as ambient temperature increases and/or barometric pressure decreases), this will be reflected by a downward shift or drop in the EP upper limit 118 on the power/speed map 114.

Power output target (PO) under EP constraints, depending on the nature of the EP protection process_TAR) The EP upper limit curve 118 cannot be exceeded. Thus, from S_minDirection S_maxMoving, the scheduled engine power output as engine speed increases necessarily follows the EP upper limit 118 until the intersection 94 is reached where the default power bump curve 98 falls below the EP upper limit 118. In the example shown, this is denoted S₁The speed occurs. Thus, at S_minAnd S₁At engine speeds in between, the scheduled engine output follows the EP upper limit 118 (as indicated by the series of arrows 120 in fig. 3); and, at S₁And S_maxAt engine speeds in between, the scheduled engine output follows the remainder of the default power bump curve 98 below the EP upper limit 118 (as indicated by arrow 122). Advantageously, such a protective power output scheduling scheme generally ensures that the engine power output remains limited enough to prevent increased wear or potential damage to the engine despite the relatively harsh environmental conditions under which the engine is currently operating. Additionally or alternativelyThis scheduling scheme provides the maximum engine power output allowed by the EP upper limit 118 under such EP constraints, which has traditionally been considered desirable for the benefit of the work vehicle operator, particularly in view of the fact that the scheduled engine power output has been significantly reduced (as indicated by the shaded area 124 in fig. 3) relative to the scheduled engine power output provided under standard operating conditions. Degradation in overall drivability (e.g., significant changes in work vehicle speed and power availability with changes in engine load) has been accepted as an inevitable consequence or necessary compromise when applying such EP engine protection measures.

Surprisingly, it has been found that by reducing engine power output under non-standard operating (EP constraints) conditions, the operator satisfaction level is increased, rather than decreased, particularly when the overall shape of the default power lobe curve is largely or entirely preserved. To this end, embodiments of the present disclosure manage engine power output under non-standard operating (EP constraints) conditions according to a dynamically adjusted power lobe curve having a shape that matches or is at least highly similar to (e.g., in the form of a compressed version of) the shape of a default power lobe curve. In an embodiment, the shape of the default power bump curve may be utilized to generate a dynamically adjusted power bump curve, and in particular, the shape of the default power bump curve is repeatedly fit below the moving EP upper limit by incorporating real-time changes in operating conditions as the EP upper limit moves (vertical translation). Additionally, embodiments of the present disclosure may likewise generate a dynamically adjusted power boost curve by fitting the shape of the power boost curve below the moving upper EP limit, thereby maintaining the availability of boost functionality (if provided normally). This unique power scheduling approach provides several benefits, which will now be discussed in conjunction with fig. 4 and 5.

Turning to fig. 4, a power/speed map 126 is shown that includes a dynamically adjusted power bump curve 128, which may be generated by controller architecture 24 when work vehicle engine control system 22 operates in an enhanced EP mode in an exemplary embodiment of the present disclosure. The axes and proportions of the power/speed map 126 correspond to the power/speed maps 94, 114, with engine power and engine speed plotted along the vertical and horizontal axes of the power/speed map 126, respectively. The default power bump curve 98 and default power boost curve 96 have been transposed or moved to the power/speed map 126 (along with corresponding reference numerals) for visual reference. In practice, however, controller architecture 24 schedules engine power output of work vehicle engine 34 in the enhanced EP mode without utilizing default power bump curve 98 or default power boost curve 96, but instead with dynamically adjusted power bump curve 128 or, in some cases, dynamically adjusted power boost curve 130, as described in detail below. The EP upper limit 118 is also moved from fig. 3 to the power/speed map 126 for reference. Although shown as a complete curve or characteristic in fig. 4 and fig. 5 and 6 (described further below), in an alternative embodiment, EP upper limit 118 may be represented as a single value or point on the power/speed map, where the single value or point indicates the maximum allowable power output above which the maximum power output value of dynamically adjusted power curves 128, 130 should not rise.

It can be seen that dynamically adjusted power lobe curve 128 having a shape that matches the shape of default power lobe curve 98 is the illustrated example. However, the vertical (power-wise) position of the dynamically adjusted power convex curve 128 is lower than the vertical position of the default power convex curve 98 (less than the power-wise position). Due to its reduced positioning, as shown in the power/speed graph 126, the dynamically adjusted power lobe curve 128 is located below or below the EP upper limit 118; this phrase does not preclude that one or more points at one or more peaks of the dynamically adjusted power bump curve 128 may coincide with the EP upper limit 118. In this example, dynamically adjusted power bump curve 128 (or the depicted portion of curve 128) begins at a shown starting point 132 having the same speed value (first speed value) as shown starting point 104 of default power bump curve 98, while shown starting point 132 possesses power output values that are (i) less than the power output value of shown starting point 100 of default power bump curve 98, and (ii) less than or substantially equal to the power output value of EP upper limit 118 at the first speed value. The peak or maximum power output value of the dynamically adjusted power bump curve 128 (here, corresponding to the starting point 132) may be located at or immediately below the EP upper limit 118. As shown in fig. 4, the dynamically adjusted power lobe curve 128 also terminates at a shown end point 134, the end point 134 having the same speed value (second speed value) as the shown end point 106 of the default power lobe curve 98, while having power output values that are (i) less than the power output value of the shown end point 102 of the default power lobe curve 98, and (ii) less than or substantially equal to the power output value of the EP upper limit 118 at the second speed value. Further, the power difference (P Δ) between the start points 100, 132 shown at the first speed value is equal to the power difference (P Δ) between the end points 102, 134 shown. In contrast, the power difference (P Δ) between the illustrated starting point 132 of the dynamically adjusted power bump curve 128 and the EP upper limit 118 at the first speed value is much smaller (e.g., one-half 100 or less) than the power difference (P Δ) between the illustrated ending point 134 of the dynamically adjusted power bump curve 128 and the EP upper limit 118 at the second speed value.

During operation of work vehicle engine control system 22 in the enhanced EP mode, controller architecture 24 generates dynamically adjusted power lobe curve 128 by repeatedly fitting the shape of default power lobe curve 98 below EP upper limit 118. In the example of fig. 4, this is accomplished entirely by vertically shifting the shape of the default power lobe curve 98 in a downward direction (i.e., in the direction of decreasing power output) to produce a dynamically adjusted power lobe curve 128. Thus, the power bump curve 128 is "dynamically adjusted" in the sense that the controller architecture 24 shifts or translates the dynamically adjusted power bump curve 128 on a repeated or iterative basis (e.g., in response to real-time sensor inputs) to match the movement in power of the EP cap 118 as the EP cap 118 rises and falls (as the case may be) along the vertical axis of the power/velocity map 126. Again, this shifting of the EP upper limit 18 occurs in relation to changes in the relevant data input aspect that affect the engine protection (EP constraint) scheme. As a generalized example, the EP upper limit 118 may be vertically displaced in a downward direction in the context of the power/velocity map 126 as the ambient temperature increases and/or as the atmospheric pressure decreases as altitude increases. As further presented on the power/speed graph 126, the dynamically adjusted power bump curve 128 is therefore also shifted downward to match the movement of the EP upper limit 118, thereby ensuring that the power bump curve 128 remains below the moving EP upper limit 118.

In the scenario of fig. 4, work vehicle engine control system 22 (fig. 1) iteratively generates or modifies dynamically adjusted power bump curve 128 by shifting the shape of default power bump curve 98 below EP upper limit 118 (without vertical scaling) to produce dynamically adjusted power bump curve 128. As work vehicle engine control system 22 continues to operate the enhanced EP mode (unless the work vehicle's power boost function is activated, as explained below), controller architecture 24 then schedules engine power output using dynamically adjusted power bump curve 128. The controller architecture 24 may utilize the dynamically adjusted power bump curve 128 to determine or identify a power output target (PO)_TAR) And then transmits one or more actuator command signals to the actuated device 76 (fig. 1) to cause the engine power output to be in accordance with the power output target (PO)_TAR) More closely consistent or coordinated; that is, the engine power output (and, as a corollary, the engine torque output) is made substantially equal to or at least toward the power output target (PO)_TAR) Note that implementing world conditions may prevent actual engine power output from being associated with a power output target (PO)_TAR) Are precisely matched. Assuming the EP constraints subsequently cease, work vehicle engine control system 22 (fig. 1) returns to controlling engine power output according to default power bump curve 98 or, if applicable, default power boost curve 96 in the manner previously described.

This method of scheduling engine power output under EP constraints has several advantages over the conventional method outlined above in connection with fig. 3. First, as a primary benefit, by implementing the enhanced EP mode described herein, the overall operator satisfaction level can be increased under EP constraints. Without being bound by theory, it is believed that this improvement in operator satisfaction is due at least in part to the maintenance of the overall shape of default power projection curve 98 in generating dynamically adjusted power projection curve 128. In general, the work vehicle operator is keenly aware of the relationship between power output and engine speed under standard operating (non-EP-constrained) conditions, and the overall retention of the default curve shape (most notably, the retention of the downwardly sloping "lobe" region 103 of the curve 128) in generating the dynamically adjusted power lobe curve 128 is more closely consistent with the operator's desire as firmly established. This may be contrasted with the shapes outlined by arrows 120, 122 in fig. 3, which vary considerably relative to the geometry of the default power convex curve 98, particularly over the segment of the path identified by arrow 120, while operatively scheduling the work vehicle engine to provide the maximum allowable power output under the EP constraints.

As a second benefit of the enhanced EP protection approach, it has been found that, contrary to intuition, operator satisfaction and driving behavior are negatively impacted when scheduling the maximum engine power output allowed by the EP upper limit 118 under EP constraints. Referring briefly again to fig. 3, and for purposes of discussion, assume that work vehicle engine 34 is currently operating at a rotational output speed of S2, which is identified in power/speed diagram 114 of fig. 3 by dashed line 136 (hereinafter "S2 speed line 136"). As shown by the first marker 138 positioned at the upper end of the speed line 136 of S2, the engine power output is scheduled at the maximum level allowed by the EP upper limit 118 according to the conventional EP protection scheme. In this case, the work vehicle operator is highly aware of: work vehicle engine 34 is operating at maximum power output due to, for example, sudden movement of the work vehicle (colloquially, a "sudden tilt" of the work vehicle) and changes in engine load. In response, the work vehicle operator is inclined to alter driving behavior by reducing the actual power output of work vehicle engine 34 to a lower level, such as that indicated by second marker 140 appearing along speed line 136 of S2, to alleviate the perceived source of engine stress. Thus, while work vehicle engine 34 is scheduled to provide the maximum allowable power output at a given engine speed (in this example, speed S2 is indicated by dashed line 136), the operator may still control the work vehicle to reduce the engine power output to a lower value (corresponding to indicia 140), but at the same time obtain a negative impression of engine performance and strain. Conversely, if the power output of work vehicle engine 34 is instead initially scheduled at a lower power output (again, generally corresponding to indicia 140 in fig. 3, where indicia 140 is located on or near power lobe curve 128 in fig. 4), this negative impression of operator interest and undesirable driving reactions tends to be minimized, if not entirely avoided.

Referring collectively to fig. 3 and 4, a dotted area or region 146 (hereinafter "power bandwidth region 146") bounded by EP upper limit 118 and dynamically adjusted power lobe curve 128 extending to speed line 144 of S1 represents the available gap or bandwidth for boosting engine power output when scheduled according to dynamically adjusted power lobe curve 128 (rather than EP upper limit 118, as is conventional). Advantageously, this newly acquired power bandwidth region 146 enables the scheduled engine power to simply increase within the power bandwidth region 146 to accommodate the increase in engine load; such as by activation of an assist function (e.g., the discharge auger 44 shown in fig. 1), climbing of the combine harvester 20, or other such action. Therefore, the overall drivability and the operator comfort of the work vehicle can be improved. Moreover, the creation of the power bandwidth region 146 also provides another significant benefit, namely the ability to maintain the availability of power boost functionality under EP constraints. In this regard, the provision of the dynamically adjusted power bump curve 128 enables the generation and use of a dynamically adjusted power boost curve when scheduling engine power output under EP constraints. An example of one such dynamically adjusted power boost curve 130 is further plotted on the exemplary power/speed plot 126 presented in fig. 4. Here, the dynamically adjusted power boost curve 130 (or at least the illustrated portion of the power boost curve 130) extends from an illustrated start point 148 to an illustrated end point 150. The dynamically adjusted power boost curve 130 is generated by fitting the shape of the default power boost curve 196 below the EP upper limit 118 in a manner similar to that described above in connection with the dynamically adjusted power bump curve 128. Again, the peak or maximum power output of the dynamically adjusted power boost curve 130 (here, corresponding to the starting point 148 described below) may be located at or immediately below the EP upper limit 118. The controller architecture 24 also generates a dynamically adjusted power boost curve 130 to fit or extend between the EP upper limit 118 and the dynamically adjusted power bump curve 128, as taken along the horizontal (speed-wise) axis of the power/speed map 126.

With continued reference to fig. 4, the shape of the default power boost curve 196 is translated or shifted vertically downward (as presented on the power/speed plot 126) to fit below the EP upper limit 118 and produce the dynamically adjusted power bump curve 128. The controller architecture 24 also modifies the positioning of the dynamically adjusted power lobe curve 128 on a repeated or "on-the-fly" basis as the EP upper limit 118 moves vertically along the engine power output axis of the power/speed map 126 with respect to changes in sensor input affecting the EP constraints. Since the shape of the dynamically adjusted power boost curve 130 matches the shape of the default power boost curve 96 in this illustrated example, the dynamically adjusted power boost curve 130 also takes the form of a relatively simple piecewise function including a first linear segment 152 having a first negative slope (corresponding to segment 110 of the default power boost curve 130) and a second linear segment 154 having a second negative slope that is less (steeper) than the first negative slope (corresponding to second linear segment 154 of segment 112 of the default power boost curve 130).

The controller architecture 24 may determine when to apply the dynamically adjusted power boost curve 128 under EP constrained conditions in substantially the same manner as when the controller architecture 24 applies the default power boost curve 96 under standard operating (non-EP constrained) conditions. Depending on the control scheme employed, the operator may still be allowed to manually activate the power boost function of the work vehicle (e.g., combine 20 shown in fig. 1) under EP constraints; for example, using manual input (e.g., buttons or switches) or by interacting with a Graphical User Interface (GUI) generated on a display device within the cab 28 of the combine harvester 20. In other cases, the power boost function may be automatically activated (i.e., activated without operator input) by the controller architecture 24 in response to the occurrence of a predetermined triggering event, such as an expected or measured increase in engine load. In the case of the exemplary combine harvester 20, the controller architecture 24 may automatically switch to the scheduled engine power output under EP constraints according to the dynamically adjusted power boost profile 130 in response to activation of a particular load intensive function (e.g., the unloading auger 44) of the combine harvester 20. This retention of power boost functionality further improves the consistency in work vehicle operation under EP constraints, providing additional improvements in operator experience.

In the above-described embodiment, the controller architecture 24 repeatedly or iteratively adjusts the vertical (power-wise) position of the EP upper limit 118, and thus the dynamically adjusted power bump curve 128 and the dynamically adjusted power boost curve 130 (if used), in response to sensed parameter changes that affect the EP constraints. Since the shape of the EP cap 118 remains consistent, the controller architecture 24 need only recall from the memory 88 the definition of the EP cap 118 and then determine the appropriate power output value for the particular engine speed (hereinafter referred to as the "fixed reference speed") to properly position the EP cap 118 in the context of the power/speed map 126. An example of such a fixed reference speed is identified in FIG. 4 by speed line 158. The marker 156 identifies the intersection between the speed line 158 and the EP upper limit 118, where the specified point is hereinafter referred to as the "EP upper limit location reference point 156". In the illustrated embodiment, where the EP ceiling 118 takes the form of a linear function with a constant slope, the controller architecture may recall from memory the fixed reference speed and the slope of the EP ceiling 118. The controller architecture 24 may then locate the EP upper limit 118 on the power/speed map 126 using the current power output value of the EP upper limit 118 at the fixed reference speed. For example, in embodiments where the controller architecture 24 includes a first controller (e.g., an ECU) and a second controller (e.g., a controller dedicated to or associated with an operator station of the work vehicle, such as an operator station enclosed by the cab 28 of the combine 20), the first controller (e.g., the ECU) may calculate the position of the EP upper limit location reference point 156 and provide the appropriate position data to the second controller; for example by publishing or making visible this information on the vehicle bus. In this case, the first controller (e.g., ECU) need only issue a single value (the current power output value of the EP upper localization reference point 156) over the bus, since the speed value of the EP upper localization reference point 156 and the shape definition of the EP upper limit 118 are known to the second controller; i.e., in an area of the memory 88 accessible by the second controller.

In further embodiments, the EP upper limit 118 may be positioned on the power/speed map 126 using different methods. For example, and noting that the speed-wise location of the maximum or peak power output value of dynamically adjusted power lobe curve 128 is known from default power lobe curve 98 for controller architecture 24 (in the present example, the speed value corresponding to the starting point 132 of power lobe curve 128), EP upper limit 118 may be represented as a single value indicative of the maximum allowable power output value for the maximum or peak power output of dynamically adjusted power lobe curve 128. The controller architecture 24 may then adjust the shape of the default power bump curve 98 such that the start point 132 of the dynamically adjusted power bump curve 128 coincides with the EP upper limit 118 at this point, or has a power output value slightly less than the EP upper limit 118 at this point. Similarly, and again noting that the speed-wise location of the maximum or peak power output value of dynamically adjusted power boost curve 130 is known from default power boost curve 96 for controller architecture 24 (in this example, the speed value corresponding to start point 148 of power boost curve 130), EP upper limit 118 may be presented as a single value indicative of the maximum allowable value of peak power output of dynamically adjusted power boost curve 130. When appropriate, the controller architecture 24 may then adjust the shape of the default power bump curve 98 such that the start point 148 of the dynamically adjusted power boost curve 130 coincides with the EP upper limit 118 at this point, or has a power output value slightly less than the EP upper limit 118 at this point.

Thus, embodiments of a work vehicle engine control system operable in an enhanced EP mode have been described, and in particular engine control system 22 (fig. 1), in which one or more dynamically adjusted power curves are used to schedule engine power output under EP constraints. In the example described above, the controller architecture of the work vehicle (i.e., the controller architecture 24 of the combine 20) generates a dynamically adjusted power bump curve (power bump curve 128 shown in fig. 4) and at least one dynamically adjusted power boost curve (power boost curve 130 further shown in fig. 4) while iteratively adjusting these curves in response to the EP upper limit motion. Further, in the above described examples, the dynamically adjusted power curves 128, 130 are modified only by displacement, and specifically by vertical (power direction) displacement or translation. This may be more fully understood with reference to fig. 5, which illustrates the dynamically adjusted power curves 128, 130 after the curves 128, 130 are further shifted down (relative to the example of fig. 4) in a manner that matches or mirrors the downward shift or drop of the EP upper limit 118. In this figure, arrow 160 represents a downward movement (i.e., movement in a direction that reduces power output) of the EP upper limit location reference point 156 relative to the location of the location reference point 156 shown in fig. 4. In further embodiments, the dynamically adjusted power curves 128, 130 may be fitted below the EP upper limit 118 using vertical scaling (compression) techniques in addition to (or possibly in lieu of) vertical shifting. For example, in various embodiments, the controller architecture 24 may dynamically adjust the power curves 128, 130 for vertical shifting and vertical scaling under EP constraints, where such vertical scaling may be applied synchronously with the vertical shifting, or may only be applied after a predetermined threshold of vertical shifting is exceeded.

Turning to fig. 6, the power/speed graph 142 illustrates an example of one manner in which the controller architecture 24 may fit the dynamically adjusted power bump curve 128 and the dynamically adjusted power boost curve 130 (if generated) below the EP upper limit 118 using a technique that combines vertical shifting (translation) and vertical scaling (compression). On the power/speed map 142 (fig. 6), the vertical (power direction) position of the EP upper limit 118 is the same as that shown in the power/speed map 126 (fig. 5). However, as can be understood by comparing these figures, both the dynamically adjusted power bump curve 128 and the dynamically adjusted power boost curve 130 are reduced (compressed) in the vertical dimension, except for a vertical downward shift in combination with a downward shift of the EP upper limit 118 in the example of fig. 6. Here, the vertical shift and scaling are applied simultaneously such that the illustrated starting point 132 of the dynamically adjusted power bump curve 128 in the example of fig. 6 coincides with the illustrated starting point 132 of the power bump curve 128 in the example of fig. 5 (which remains below or immediately below the EP upper limit 118), while the illustrated end point 134 of the dynamically adjusted power bump curve 128 in the example of fig. 6 has a higher output value than the illustrated starting point 132 of the power bump curve 128 in the example of fig. 5. As a corollary, the power difference (P) between the start point 132 and the end point 134 of the dynamically adjusted power bump curve 128 in the example of FIG. 6_Δ) (or more generally, maximum and minimum power output values, respectively) is less than the power difference (P) between the starting point 132 and the ending point 134 of the power bump curve 128 in the example of fig. 5_Δ). Further, the average slope of the dynamically adjusted power bump curve 128 in the example of fig. 6 is less than (closer to zero than) the average slope of the dynamically adjusted power bump curve 128 in the example of fig. 6 due to the flattening of the curve that occurs as a result of such vertical scaling or compression.

The above statements apply equally to the dynamically adjusted power boost curve 130, which in the example of fig. 6 is vertically shifted (translated) and vertically scaled (compressed). Thus, the dynamically adjusted power boost curve 130 is generated to have a curve shape that is essentially a shifted and compressed version of the curve shape of the default power bump curve 98. Further, the illustrated endpoint 150 of the dynamically adjusted power boost curve 130 in the example of fig. 6 has a higher power output value (and is located above the illustrated endpoint 102 of the default power bump curve 98) than the illustrated endpoint 150 of the power boost curve 130 in the example of fig. 5. Additionally, the average slope (and power range) of the dynamically adjusted power boost curve 130 in the example of fig. 6 is less than the average slope (and power range) of the dynamically adjusted power boost curve 130 in the example of fig. 5.

Moving finally to fig. 7, a flow chart sets forth an exemplary process 162 that may be carried out by the controller architecture 24 under potential EP constraints. The process 162 (hereinafter "EP enhancement process 162") includes a plurality of process steps 164, 166, 168, 170, 172, 174, 176, 178, each of which is described in turn below. Each step shown generally in fig. 7 may require a single process or multiple sub-processes, depending on the particular manner in which EP enhancement process 162 is implemented. Further, the steps shown in fig. 7 and described below are provided as non-limiting examples only. In alternative embodiments of the EP enhancement process 162, additional process steps may be performed, certain steps may be omitted, and/or the process steps shown may be performed in an alternative order.

The EP enhancement process 162 begins at step 164 in response to the occurrence of a predetermined triggering event (such as the initiation of a work vehicle) or in response to entry of an operator input that activates the EP enhancement process 162. After the start process 162, the controller architecture 24 proceeds to step 166 and collects data parameters for determining whether operation under EP constraints is warranted. For example, and as previously described, the controller architecture 24 may collect data inputs indicative of the atmospheric pressure and ambient temperature of the environment in which the work vehicle (here, the combine 20) is operating. The controller architecture 24 may then utilize these parameters to determine the appropriate vertical (power-wise) position of the EP upper limit 118, as presented on a power/speed chart similar or identical to the charts 126, 142 described above. Using this information, controller architecture 24 then determines whether to place work vehicle engine control system 22 in the enhanced EP mode at step 170. In particular, and as previously described, assuming that the EP upper limit 118 contacts the default power bump curve 98 (or comes within a predetermined relative proximity thereof) (fig. 4-6), the controller architecture 24 may determine that it is warranted to enter or place in the enhanced EP mode. If it is determined that work vehicle engine control system 22 should enter the enhanced EP mode (or continue to operate in the enhanced EP mode), controller architecture 24 proceeds to step 172 and transitions operation in the standard operation (non-EP-restricted) mode to operation in the enhanced EP mode, as described below. If not, if it is determined that work vehicle engine control system 22 is not properly placed in the enhanced EP mode (or assuming a return to the standard operating mode from the enhanced EP mode (if currently operating)), controller architecture 24 returns to step 166 and continues to monitor the relevant data inputs. Additionally, as shown in fig. 7, at an intermediate step 168, a termination check may be performed at some point in the process flow to determine whether the current iteration of the EP enhancement process 162 should be terminated.

Advancing to step 172 of the EP enhancement process 162, the controller architecture 24 operatively enters the enhanced EP mode and determines whether the EP power boost function (if provided) is desired to be activated at the present time. In certain embodiments, the EP power boost function may be activated by operator input; and in other cases, automatically activated by the controller architecture 24 in response to a predetermined triggering event, such as activation of an auxiliary work vehicle function imposing a relatively large secondary or "parasitic" load on the work vehicle engine. As previously mentioned, an example of such an auxiliary work vehicle function in the case of combine harvester 20 (fig. 1) is the activation of unloading auger 44. As a second example, in the case of a tractor having a PTO stub, a trigger event may indicate that the tractor engine is currently driving a relatively high demand load (e.g., a baler or similar implement being pulled by a tractor) through the PTO stub. If the dynamic EP power boost function is desirably activatedIn particular, the controller architecture 24 proceeds to step 174, builds or generates the dynamically adjusted power boost curve 130 using a process similar or identical to the previously described process (by fitting the shape of the default power boost curve 96 below the EP upper limit 118), and then uses the newly generated dynamically adjusted power boost curve 130 to determine an appropriate power output target (PO) as a function of the current engine speed_TAR). Conversely, if it is instead determined at step 172 that the dynamic EP power boost function is not desirably activated, the controller architecture 24 proceeds to step 176 and performs a similar action for the dynamically adjusted power bump curve. In this latter aspect, at step 176, the controller architecture 24 builds the dynamically adjusted power boost curve 130 using a process similar or identical to the previously described process (by fitting the shape of the default power bump curve 98 below the EP upper limit 118), and then uses the dynamically adjusted power bump curve 128 to determine an appropriate power output target (PO) as a function of the current engine speed_TAR)。

After performing either step 174 or step 176 of the EP enhancement process 162, the controller architecture 24 proceeds to step 178 and outputs the target (PO) according to the newly determined power output_TAR) To schedule engine power output. Generally, this can be done by targeting the Power Output (PO)_TAR) Converts into corresponding actuation adjustment commands, and then provides such commands to appropriate actuation devices, such as one or more of the actuated devices 76 described above in connection with the exemplary combine 20 (fig. 1). As previously discussed, such commands may cause various actuators to adjust the rate of metered fuel flow to the combustion chambers of work vehicle engine 34 and/or may affect the air pressure or temperature within the engine combustion chambers (by modulating one or more valves 58, 66 included in EGR system 46). Thereafter, the controller architecture 24 returns to step 166 of the EP enhancement process 162 and repeats the process steps described above. In this manner, controller architecture 24 may execute EP enhancement process 162 to identify an appropriate time to place work vehicle engine control system 22 in the enhanced EP mode; and when it is done so, it is,scheduling engine power output according to the selected one of the dynamically adjusted power curves.

Enumerated examples of work vehicle engine control systems

For ease of reference, the following examples of work vehicle engine control systems are further provided and numbered.

1. In an embodiment, a work vehicle engine control system includes a memory storing a first default power curve having a first curve shape as presented on a power/speed map, the power/speed map including a vertical axis along which a power output of a work vehicle engine increases in an upward direction, and the power/speed map including a horizontal axis along which an engine speed increases in a rightward direction. The controller architecture is connected to the memory and is operable in an enhanced EP mode in which the controller architecture: (i) generating a first dynamically adjusted power curve by repeatedly fitting a first curve shape below an upper EP limit of movement as presented on the power/velocity graph; (ii) determining a power output target (PO) corresponding to a current speed of a work vehicle engine using a first dynamically adjusted power curve_TAR) (ii) a And (iii) output target (PO) according to power_TAR) Power output of the work vehicle engine is scheduled.

2. The work vehicle engine control system of example 1, wherein the work vehicle includes at least a first environmental sensor that provides data indicative of an environmental parameter affecting combustion within the work vehicle engine. The controller architecture is further configured to repeatedly establish a current vertical position of the upper EP limit of movement as presented on the power/velocity map using data provided by the first environmental sensor.

3. The work vehicle engine control system of example 1, wherein the work vehicle includes at least a first engine actuation device controllable to vary the metered amount of fuel or fuel supplied to the work vehicle engine per combustion cycleThe amount of oxygen. The controller architecture is configured to output a target (PO) according to a power output_TAR) When scheduling power output of the work vehicle engine, an actuation command is sent to a first engine actuation device.

4. The work vehicle engine control system of example 1, wherein the first default power curve and the dynamically adjusted power lobe curve comprise a default power lobe curve and a dynamically adjusted power lobe curve, respectively. The controller architecture is configured to determine a power output target (PO) using the dynamically adjusted power bump curve at least in selected cases_TAR)。

5. The work vehicle engine control system of example 4, wherein the controller architecture generally operates in the non-enhanced EP mode, and the controller architecture is configured to transition from the non-enhanced EP mode to the enhanced EP mode when the moving upper EP limit falls within a predetermined proximity of a default power bump curve as presented on the power/speed map.

6. The work vehicle engine control system of example 5, wherein the controller architecture is configured to transition from the non-enhanced EP mode to the enhanced EP mode when the default power bump curve intersects the moving EP upper limit due to a shift in the moving EP upper limit as presented on the power/speed map.

7. The work vehicle engine control system of example 4, wherein the default power bump curve has a curved shape with a negative slope that becomes increasingly greater as engine speed increases.

8. The work vehicle engine control system of example 4, wherein the work vehicle has a power boost function and the memory further stores a default power boost curve having a second curve shape. The controller architecture is further configured to utilize the dynamically adjusted power bump curve to determine a power output target (PO) when the power boost function is turned off_TAR). When the power boost function is engaged, the controller architecture is configured to: (i) by fitting a second curve shape below the upper EP limit for movement at its current vertical position as presented on the power/velocity diagramGenerating a dynamically adjusted power boost curve, and (ii) determining a power output target (PO) for scheduling power output of the work vehicle engine using a second dynamically adjusted power curve_TAR)。

9. The work vehicle engine control system of example 8, wherein the work vehicle is in the form of a combine having an unloading auger. The controller architecture is configured to automatically engage the power boost function when the discharge auger is operating.

10. The work vehicle engine control system of example 8, wherein the controller architecture generates the dynamically adjusted power boost curve to extend between the upper EP limit and the dynamically adjusted power lobe curve, as taken along a vertical axis of the power/speed map.

11. The work vehicle engine control system of example 1, wherein the controller architecture is configured to generate the first dynamically adjusted power curve using a technique that includes shifting the first curve shape to fit below an upper EP limit for the shift as presented on the power/speed map.

12. The work vehicle engine control system of example 1, wherein the controller architecture is configured to generate the first dynamically adjusted power curve using a technique that includes scaling the first curve shape to fit below an upper EP limit for movement as presented on the power/speed map.

13. The work vehicle engine control system of example 1, wherein the controller architecture is configured to generate the first dynamically adjusted power curve using a technique that includes shifting and scaling a first curve shape to fit below an upper EP limit for movement as presented on the power/speed map.

14. In further embodiments, a work vehicle engine control system includes a memory and a controller architecture connected to the memory and operable in an enhanced EP mode. The memory stores a default power bump curve having a first curve shape as presented on a power/speed map comprising a horizontal axis and a vertical axisEngine speed increases in a rightward direction along the horizontal axis, and power output increases in an upward direction along the vertical axis. The memory also stores a default power boost curve having a second curve shape as presented on the power/speed map. When placed in enhanced EP mode and the power boost function of the work vehicle is turned off, the controller architecture (i) generates a dynamically adjusted power bump curve by repeatedly fitting a first curve shape below an upper EP limit of movement as presented on the power/speed map; and (ii) determining a power output target (PO) corresponding to a current speed of the work vehicle engine using the dynamically adjusted power lobe curve_TAR). In contrast, when placed in enhanced EP mode and the power boost function of the work vehicle is turned off, the controller architecture: (i) generating a dynamically adjusted power boost curve by repeatedly fitting a second curve shape below the moving upper EP limit; and (ii) determining a power output target (PO) corresponding to a current speed of the work vehicle engine using the dynamically adjusted power boost curve_TAR). Whether the power boost function is engaged or disengaged, the controller architecture then outputs the target (PO) according to the power_TAR) To schedule the power output of the work vehicle engine.

15. The work vehicle engine control system of example 14, wherein the work vehicle comprises a combine having an unloading auger. The controller architecture is configured to automatically engage the power boost function when the discharge auger is running.

Conclusion

Accordingly, the foregoing has provided embodiments of a work vehicle engine control system operable in an enhanced EP mode. In an embodiment, a work vehicle engine control system utilizes at least one dynamically adjusted power curve when scheduling power output of a work vehicle engine under EP constraints. The dynamically adjusted power curve(s) is generated to have a shape that matches or nearly matches (including a compressed version thereof) the corresponding curve shape of the non-dynamic (static) default power curve(s), which are otherwise used for engine scheduling under normal operating (non-EP-constrained) conditions. By using such dynamically adjusted power curve(s) (iteratively adjusted or modified according to changes in the EP upper limit), the engine control system enhances the consistency in the overall drivability and engine behavior of the work vehicle, thereby increasing the operator satisfaction level. Additionally, in embodiments where the engine control system generates both a dynamically adjusted power bump curve and a power boost curve when operating in the enhanced EP mode, the work vehicle engine control system maintains the availability of the power boost function of the work vehicle under EP constraints to bring about even further improvements in operator satisfaction levels and work vehicle efficiency.

As will be appreciated by one skilled in the art, aspects of the disclosed subject matter may be described in terms of methods, engine control systems, and computer program products. In particular, with respect to computer program products, embodiments of the disclosure may consist of or include a tangible, non-transitory storage medium storing computer-readable instructions or code for performing one or more of the functions described throughout this document. As will be apparent, such computer-readable storage media may be implemented with any currently known or later developed memory type, including various types of Random Access Memory (RAM) and read-only memory (ROM). Further, embodiments of the present disclosure are open or "agnostic" to the particular memory technology employed, noting that magnetic storage solutions (hard disk drives), solid state storage solutions (flash memory), optimal storage solutions, and other storage solutions all potentially contain computer-readable instructions for carrying out the functions described herein. Similarly, the systems or devices described herein may also include memory (e.g., as firmware or any combination of other software executing on an operating system) that stores computer-readable instructions that, when executed by a processor or processing system, direct the system or device to perform one or more of the functions described herein. Such computer readable instructions or code, when executed locally, may be copied or distributed to the memory of a given computing system or device in a variety of different ways, such as by transmission over communication networks including the internet. Thus, embodiments of the disclosure should not be limited, in general, to any particular set of hardware or memory structures, or to the particular manner in which computer-readable instructions are stored, unless otherwise explicitly stated herein.

Finally, as used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

The description of the present disclosure has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the disclosure in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the disclosure. The embodiments expressly referenced herein were chosen and described in order to best explain the principles of the disclosure and its practical application, and to enable others of ordinary skill in the art to understand the disclosure for various alternatives, modifications, and variations of the described example(s). Accordingly, various embodiments and implementations other than those explicitly described are within the scope of the following claims.