阅读说明：本技术 利用补偿学习策略增强发动机部件诊断稳健性的系统和方法 (System and method for enhancing engine component diagnostic robustness using compensation learning strategy ) 是由 A·甘塞利黎 P·L·克劳德 F·思亚诺 P·奥兰多 F·塞萨 于 2019-05-27 设计创作，主要内容包括：本发明公开了一种利用补偿学习策略诊断内燃机部件的方法,该方法包括通过致动器命令操作部件,以建立代表第一部件操作模式的第一操作参数。该方法还包括识别对第一操作模式产生负影响的第一参数的漂移。该方法还包括确定对致动器命令的补偿,以在第一操作模式期间抵消第一参数的漂移。该方法还包括使用所确定的致动器命令补偿来确定对第一参数的补偿。该方法还包括将所确定的参数补偿直接应用于第一参数。该方法还包括利用致动器命令操作部件,从而建立代表第二部件操作模式的第二操作参数。此外,该方法包括识别对第二操作模式产生负影响的第二参数的漂移。(A method for diagnosing a component of an internal combustion engine using a compensation learning strategy includes commanding an operating component via an actuator to establish a first operating parameter representative of an operating mode of a first component. The method also includes identifying a drift of the first parameter that negatively affects the first mode of operation. The method also includes determining compensation for the actuator command to offset drift of the first parameter during the first mode of operation. The method also includes determining a compensation for the first parameter using the determined actuator command compensation. The method also includes applying the determined parameter compensation directly to the first parameter. The method also includes commanding the operational component with the actuator to establish a second operational parameter representative of an operational mode of the second component. Further, the method includes identifying a drift of a second parameter that negatively affects a second mode of operation.)

1. A method for engine component diagnostics using a compensation learning strategy, the method comprising:

operating the engine component with an actuator command issued by an electronic controller to establish a first operating parameter representative of a first component operating mode;

identifying, via the electronic controller, a drift of the first operating parameter that negatively affects the first operating mode;

determining, via the electronic controller, a commanded compensation for the actuator command to offset the drift in the first operating parameter during the first operating mode;

determining, via the electronic controller, a parameter compensation for the first operating parameter utilizing the determined compensation for the actuator command;

applying the determined parameter compensation directly to the first operating parameter;

operating the engine component with the actuator command to establish a second operating parameter representative of a second component operating mode; and

identifying, via the electronic controller, a drift of the second operating parameter that negatively affects the second operating mode while applying the determined parameter compensation directly to the first operating parameter without applying the determined command compensation to the actuator command.

2. The method of claim 1, wherein the step of determining the parameter compensation comprises converting the commanded compensation to an incremental reference compensation value for direct application to the first operating parameter while identifying drift in the second operating parameter.

3. The method of claim 2, wherein said step of converting said determined parameter compensation to said incremental reference compensation value comprises using a mathematical relationship programmed into said controller.

4. The method of claim 2, wherein said step of converting said determined parameter compensation to said incremental reference compensation value comprises accessing a look-up table of said determined parameter compensation value and incremental reference compensation value for said actuator command.

5. The method of claim 1, wherein the engine is a compression ignition engine and the component is an injector configured to inject fuel into the engine.

6. The method of claim 5 wherein the first operating parameter is a relatively small injection amount and the first operating mode is pilot fuel injection.

7. The method of claim 6, wherein the second operating parameter is a relatively large injection amount and the second operating mode is main fuel injection.

8. The method of claim 7, wherein the step of identifying the drift of the second operating parameter while applying the determined parameter compensation directly to the first operating parameter without applying the determined command compensation to the actuator command includes at least one of maintaining a pre-ignition temperature in the combustion chamber and maintaining combustion stability within the engine.

9. The method of claim 6, wherein the second operating parameter is a relatively small injection amount and the second operating mode is a post-combustion fuel injection.

10. The method of claim 9, wherein the engine includes an exhaust After Treatment (AT) device configured to reduce engine exhaust emissions, and wherein the step of identifying the drift of the second operating parameter while applying the determined parameter compensation directly to the first operating parameter without applying the determined command compensation to the actuator command includes maintaining efficient operation of the AT device and thus a reduction in engine exhaust emissions.

Disclosure of Invention

A method of diagnosing an internal combustion engine component with a compensation learning strategy includes operating the engine component with actuator commands issued by an electronic controller. Specifically, the actuator command is used to establish a first operating parameter representative of the first component operating mode. The method also includes identifying, via the electronic controller, a drift of a first operating parameter that negatively affects the first operating mode. The method also includes determining, via the electronic controller, a commanded compensation for the actuator command to offset a drift of the first operating parameter during the first operating mode. The method also includes determining, via the electronic controller, a parameter compensation for the first operating parameter using the determined compensation for the actuator command. The method also includes applying the determined parameter compensation directly to the first operating parameter. The method also includes operating the engine component with the actuator command to establish a second operating parameter representative of an operating mode of the second component. Further, the method includes identifying, via the electronic controller, a drift of a second operating parameter that negatively affects the second operating mode while applying the determined parameter compensation directly to the first operating parameter without applying the determined command compensation to the actuator command.

The step of determining the parameter compensation may include converting the commanded compensation to an incremental reference compensation value for direct application to the first operating parameter while identifying drift in the second operating parameter.

The step of converting the commanded compensation to an incremental reference compensation value may include using a mathematical relationship programmed into the controller.

The step of converting the commanded compensation to an incremental reference compensation value may include accessing an empirically collected look-up table of determined compensation values for the actuator command and the incremental reference compensation value.

The engine may be a compression ignition engine and the component may be an injector configured to inject fuel into the engine.

The first operating parameter may be a relatively small injection quantity and the first operating mode is pilot fuel injection.

The second operating parameter may be a relatively large injection amount and the second operating mode is main fuel injection.

The step of identifying a drift in the second operating parameter while applying the determined parameter compensation directly to the first operating parameter without applying the determined command compensation to the actuator command may include maintaining a pre-ignition temperature in the combustion chamber and maintaining combustion stability in the engine.

Alternatively, the second operating parameter may be a relatively small injection amount and the second operating mode may be a post-combustion fuel injection.

The engine may include an exhaust after-treatment (AT) device configured to reduce exhaust emissions of the engine. In such a case, the step of identifying a drift in the second operating parameter while applying the determined parameter compensation directly to the first operating parameter without applying the determined command compensation to the actuator command may include AT least one of maintaining efficient operation of the AT device and thus maintaining engine exhaust emission reduction.

A system for diagnosing an internal combustion engine component using a compensation learning strategy, such as by an electronic controller implementing the above method, is also disclosed. Vehicles may use such systems.

The above features and advantages and other features and advantages of the present invention are readily apparent from the following detailed description of the embodiments and the best modes for carrying out the disclosure when taken in connection with the accompanying drawings and appended claims.

Drawings

FIG. 1 is a schematic plan view of a vehicle having an internal combustion engine coupled to an exhaust system having an Aftertreatment (AT) system with a plurality of AT devices for reducing exhaust emissions, including a system for implementing a compensation learning strategy for diagnosing engine components using an electronic controller.

FIG. 2 is a close-up schematic view of an engine cylinder having a combustion chamber and representative engine components of the internal combustion engine shown in FIG. 1.

FIG. 3 is a flow chart of a method for diagnosing the engine components shown in FIGS. 1 and 2 using a compensation learning strategy.

Detailed Description

Referring to the drawings, wherein like reference numbers refer to like components throughout the several views, FIG. 1 schematically illustrates a motor vehicle 10. The vehicle 10 includes an internal combustion engine 12 configured to propel the vehicle via drive wheels 14. The internal combustion engine 12 may be a compression ignition engine or a diesel engine. Generally speaking, internal combustion in the diesel engine 12 occurs when a specified amount of ambient intake airflow 16 is mixed with a metered amount of fuel 18 supplied from a fuel tank 20 and the resulting air-fuel mixture is compressed into the combustion chambers 13A of the engine cylinders 13 (shown in FIG. 2).

As shown, the engine 12 may include an exhaust manifold 22 configured to collect exhaust gases from the engine cylinders 13. The engine also includes a turbocharger 24, the turbocharger 24 being in fluid communication with the cylinder 13, such as through the exhaust manifold 22. The turbocharger 24 is driven by the flow of exhaust gas, particularly exhaust gas 26 that is released by the various cylinders 13 of the engine 12 after each combustion event, such as through the exhaust manifold 22. The turbocharger 24 is connected to an exhaust system 28, and the exhaust system 28 receives the exhaust gas 26 and ultimately discharges the exhaust gas to the environment, typically to the side or rear of the vehicle 10. The turbocharger 24 also uses the flow of exhaust gas 26 to pressurize the intake airflow 16.

The vehicle 10 also includes an engine exhaust Aftertreatment (AT) system 30. The AT system 30 includes a plurality of exhaust aftertreatment devices configured to sequentially remove a majority of the carbonaceous particulate by-products and the exhaust constituents of the engine combustion from the exhaust gas 26. As shown in fig. 1 and 2, the AT system 30 operates as part of the exhaust system 28. The AT system 30 includes AT least one AT device, for example, a first AT device 32 disposed downstream of the turbocharger 24 and a second AT device 34 disposed downstream of the first AT device. The first AT device 32 may be closely coupled to the turbocharger 24 and disposed within the engine compartment 11 of the vehicle 10 for close proximity to the engine 12. This close coupling of the first AT device 32 to the engine 12 may provide a compact packaging arrangement such that the time for the AT system 30 to activate (i.e., ignite) during the aftertreatment of the exhaust gas 26 after cold starting the engine 12 is minimized. The AT system 30 may also include other AT devices (not shown) located in the exhaust gas flow downstream of the first and second AT devices 32, 34.

As shown, the first AT device 32 may be a Diesel Oxidation Catalyst (DOC), while the second AT device 34 may be a Selective Catalytic Reduction (SCR) catalyst and filter. The primary function of a DOC is to reduce carbon monoxide (CO) and non-methane hydrocarbons (NMHC). When present, the DOC is additionally configured to generate nitrogen dioxide (NO2), which may be used by an SCR disposed remotely downstream from the DOC. The primary function of the SCR is to reduce the concentration of nitrogen oxides (NOx) in the exhaust gas 26.

The AT system 30 also includes an exhaust passage 22A, which exhaust passage 22A may be part of the exhaust manifold 22, configured to deliver the exhaust gas flow 26 from the engine cylinder 13 to the turbocharger 24, and an exhaust passage 36 configured to deliver the exhaust gas 26 aft of the turbocharger 24 to the first AT device 32. The intake airflow 16 is supplied to the engine 12 via an intake passage 38 for mixing with the fuel 18 to produce combustion to operate the engine and produce an airflow of exhaust gas 26. The engine 12 may include engine components 40, the engine components 40 being used to operate the engine components with actuator commands via control signals issued by an electronic controller, as will be described in detail below.

The engine component 40 may be a component that employs a learning strategy that diagnoses zero and control ranges for calibration that would benefit from self-calibration without shutting down. Specifically, the engine component 40 may be a fuel injector that is supplied with fuel 18 via an injector rail 42 and that is used to inject the fuel 18 into the engine cylinder 13. While the engine 12 may include other examples of engine components 40, such as sensors and actuators, the remainder of the disclosure will focus on the fuel injector embodiments of the subject components. Thus, from this point on, the fuel injector will be labeled with the numeral 40. The internal combustion engine 12 may typically have a multi-cylinder configuration, with at least one such fuel injector 40 employed per cylinder 13.

An airflow sensor 44 may be disposed in intake passage 38 and configured to detect an amount of airflow 16 supplied to engine 12 during operation thereof, and such data may be used to control an amount of fuel 18 injected into cylinders 13. The exhaust passage 46 is configured to receive treated exhaust gas 26A aft of the AT device 34 and to pass the treated exhaust gas through the remainder of the exhaust system 28 to entrain exhaust gas 26A aft of the second treated second AT device 34 and to pass the treated exhaust gas through the remainder of the exhaust system 28 and the remainder of the AT system 30.

The vehicle 12 also includes a system 48, the system 48 configured to perform diagnostics of the component 40 using a compensation learning strategy that will be described in detail below. The system 48 is also configured to reduce the impact of learning compensation of an operating parameter of one assembly 40 on diagnostic observations of an operating parameter of another assembly 40 without adversely affecting the performance of the subject component. The vehicle 10 also includes an electronic controller 50 configured to regulate the AT system 30, and thus, the controller may be part of the AT system. The controller 50 is part of the system 48 and may be a stand-alone unit or part of an Electronic Control Unit (ECU) that regulates operation of the engine 12. The controller 50 is disposed on the vehicle 10 and includes a processor and a non-transitory memory that is readily accessible. Instructions for controlling the operation of the AT system 30 are programmed or recorded in the memory of the controller 50, and the processor is configured to execute the instructions from the memory during operation of the vehicle 10.

The controller 50 is generally programmed to adjust the injector 40 to inject the fuel 18 into the cylinder 13 to enable operation of the engine 12. Specifically, controller 50 is programmed to operate injector 40 with actuator commands 52 (e.g., communicated via control signals) during a particular first event (e.g., during a cold start) to establish first operating parameters 54 representative of a first mode of component 40 (i.e., injector) operation. The first operating parameter is a relatively small injection quantity, e.g. a single injection per engine stroke in 1-3mm per cylinder³In the range of/stroke. The first mode of operation is to activate a pilot fuel injection approximately 10 degrees Before Top Dead Center (BTDC) to heat the combustion chamber 13A. In this embodiment, the first mode of operation of injector 40 may be, for example, 1-3mm from a single injection for each engine stroke³The small injection amount per stroke (injector) is defined, as described above, and is therefore configured to support a cold start of the engine 12.

Controller 50 is also programmed to identify or diagnose a drift in first operating parameter 54 that negatively affects (i.e., causes a fault in) the first mode of operation of injector 40. Controller 50 is also programmed to determine a command offset 56 for actuator command 52 to offset a drift in first operating parameter 54 during the first mode of operation of injector 40. The controller 50 is also programmed to determine a parameter offset 58 for the first operating parameter 54 using the determined offset 56 for the actuator command 52. Such determination of parameter compensation 58 may include converting command compensation 56 to a value of incremental reference compensation 60 for direct application to first operating parameter 54.

Controller 50 is also programmed to apply the determined parameter compensation 58 directly to first operating parameter 54. Specifically, the determined parameter compensation 58 is directly applied to the first operating parameter 54, thereby counteracting drift in the identified first operating parameter during the first mode of operation of the injector 40, without directly applying the determined command compensation 56 to the actuator command 52. In general, drift in an operating parameter indicates a loss of accuracy in achieving the subject parameter, i.e., deviating the parameter from its target value. In the event of a drift in the first operating parameter during the first mode of operation of the injector 40, an incorrect amount of fuel 18 may be indicated to be injected into the cylinder 13. Injecting an incorrect amount of fuel 18 into the cylinder 13 may be detrimental to the combustion efficiency of the engine and to the operation of the AT devices 32, 34 in removing particulate by-products and the exhaust constituents of combustion from the exhaust gas 26.

Controller 50 is also programmed to operate injector 40 using actuator commands 52 to establish second operating parameters 62 representative of the operation of injector 40 in the second mode. The second operating parameter 62 may be a relatively large injection volume (e.g., between 5-150 mm)³In a/stroke range), a cumulative amount of fuel injected per engine cycle, multiple injections per stroke for multiple cylinders. The second operating mode is main combustion fuel injection, which is initiated at around 2-5 degrees BTDC (the main injection typically occurs in the full range of 20 degrees BTDC to 5 degrees ATDC in a typical diesel engine) to initiate complete combustion in the combustion chamber 13A. In this embodiment, the second mode of operation of the injector 40 may be, for example, from 5-150mm³The large injection quantity per stroke range is defined and configured to support operation of the engine 12 in a normal operating temperature range and to generate engine torque in response to operator demand. Other examples of main combustion fuel injection may include particular operating conditions, such as starting and fueling of the engine 12 during a transient maneuver.

Can replaceAlternatively, the second operating parameter 62 may be a relatively small injection quantity, e.g., a single injection at 1-3mm per engine stroke in a single cylinder³In the/stroke range. In this embodiment, the second mode of operation of the injector 40 may be activation of post-combustion fuel injection approximately 100 milliseconds or 10-30 degrees After Top Dead Center (ATDC). The post-combustion fuel injection may be, for example, from 1 to 3mm³A smaller injection quantity in the/stroke range is defined and configured to maintain the effective operating temperature of the AT devices 32, 34 after the main combustion in the cylinder 13. Thus, the step of identifying a drift in the second operating parameter 62 while applying the determined parameter compensation 58 directly to the first operating parameter 54 and not applying the determined command compensation 56 to the actuator command 52 includes at least one of maintaining a pre-ignition temperature in the combustion chamber 13A and maintaining combustion stability of the engine 12.

In addition, controller 50 is programmed to identify or diagnose a drift in second operating parameter 62 that negatively affects the second mode of operation of injector 40. The identification of the drift of the second operating parameter 62 occurs when the determined parameter compensation is applied directly to the first operating parameter 54 without applying the determined command compensation 56 to the actuator command 52. Accordingly, the controller 50 is configured to perform non-intrusive diagnostics of the drift of the second operating parameter 62 during the second operating mode, i.e., during the second operating parameter 62 diagnostics, the compensated first operating parameter 54 and the first operating mode are not affected. Such diagnostics also allow the controller to identify the health and performance of the component (e.g., injector) 40 to support the second injector operating mode without adversely affecting the injector's ability to support the first operating mode.

The controller 50 may also be configured to determine and apply compensation to the second operating parameter 62 to counteract the identified drift during the second mode of operation without affecting the first mode of operation of the injector 40. By identifying a drift in the second operating parameter 62 while applying the determined parameter compensation 58 directly to the first operating parameter 54 and not applying the determined command compensation 56 to the actuator command 52, the controller 50 is configured to maintain efficient operation of the AT devices 32, 34, and thus a reduction in engine exhaust emissions.

The determining step of the parameter compensation 58 may include converting the commanded compensation 56 to an incremental reference compensation value 64 for direct application to the first operating parameter 54. The incremental reference compensation value 64 is intended to provide a specific incremental change directly to the first operating parameter 54, bypassing modification of the actuator command 52 to allow identification of a drift of the second operating parameter 62. Controller 50 may also be configured to convert command compensation 56 to incremental reference compensation value 64 via mathematical relationship 66. The mathematical relationship 66 is intended to be programmed into the controller 50 and used to calculate the incremental reference compensation value 64 in response to the determined commanded compensation value 56. Alternatively, the controller 50 may be programmed to convert the determined commanded compensation value 56 to the incremental reference compensation value 64 by accessing an empirically derived data look-up table 68 of the determined actuator commanded compensation 56 and the incremental reference compensation value 64. In other words, the data lookup table 68 includes the determined actuator command offsets 56 for cross-referencing or correlating the operation of the injector 40 with the empirically derived incremental reference offset value 64.

The controller 50 may also be programmed to determine the pressure in the injector rail 42, as well as the injection timing of the fuel injectors 40 for operating the engine 12. The controller 50 may also be programmed to determine the number of injections or pulses of fuel 18 produced by each fuel injector 40 per engine cycle. In general, system 48 uses a compensation learning strategy to perform non-intrusive diagnostics of engine component 40 performance drift during the second mode of operation such that compensated operating parameters 54, and the accompanying first mode of operation, are not affected.

FIG. 3 illustrates a method 100 of using a compensation learning strategy to diagnose an internal combustion engine component 40 using the compensation learning strategy, as described above in FIGS. 1 and 2. Method 100 may be performed via electronic controller 50 programmed to regulate operation of engine 12. The method 100 is initiated in block 102 by operating the engine 12 with an engine component (e.g., the fuel injector 40). Throughout the method, and beginning with block 102, the method generally includes supplying predetermined amounts of airflow 16 and fuel 18 to the engine 12. After frame 102, the method proceeds to frame 104, wherein the method includes operating the engine component 40 using the actuator command 52 issued by the electronic controller 50 to establish the first operating parameter 54 representative of the first component operating mode.

After block 104, the method proceeds to block 106. In block 106, the method includes identifying, via the electronic controller 50, a drift of the first operating parameter 54 that negatively affects the first operating mode. After frame 106, the method proceeds to frame 108, where the method includes determining, via the electronic controller 50, a command offset 58 to the actuator command 52 to offset the drift of the first operating parameter 54 during the first operating mode. After block 108, the method proceeds to block 110. In block 110, the method includes determining, via the electronic controller, a parameter compensation 58 for the first operating parameter 54 using the determined compensation 58 for the actuator command 52.

The step of determining the parameter compensation 58 in block 110 may include converting the commanded compensation to the incremental reference compensation value 64 for direct application to the first operating parameter 54 while identifying a drift in the second operating parameter 62. The step of converting the determined parameter compensation 58 to the incremental reference compensation value 64 may include utilizing a mathematical relationship 66 programmed into the controller 50, as described above with reference to fig. 1 and 2. Alternatively, the step of converting the determined parameter compensation 58 to the incremental reference compensation value 64 may include accessing a look-up table 68 of the determined parameter compensation value 58 and the incremental reference compensation value for the actuator command 52.

After block 110, the method moves to block 112. In block 112, the method includes applying the determined parameter compensation 58 directly to the first operating parameter 54 to counteract drift of the first operating parameter 54 during the first mode of operation without applying the determined command compensation 58 to the actuator command 52. After block 112, the method may proceed to block 114. In frame 114, the method may include operating the engine component 40 with the actuator command 52 to establish the second operating parameter 62 representing the second mode of component operation.

After block 114, the method moves to block 116. In block 116, the method includes identifying, via the electronic controller, a drift of the second operating parameter 62 that negatively affects the second operating mode. The subject identification of the drift of the second operating parameter 62 occurs where the controller 50 applies the determined parameter compensation 58 directly to the first operating parameter 54 and does not apply the determined command compensation 56 to the actuator command 52. After block 116, the method may proceed to block 118, where the method includes determining and applying, via the electronic controller 50, compensation for the second operating parameter 62 of the component 40 to counteract component drift during the second mode of operation. After either of frames 116 or 118, the method may loop back to frame 104 to continue operating the engine component 40 using the actuator command 52 to establish the first operating parameter 54 representative of the first component operating mode.

Accordingly, the controller 50 may be programmed to continuously monitor the operation of the engine 12, the engine components (e.g., injectors) 40, and the AT system 30, and to perform non-intrusive diagnostics of the performance drift of the subject component 40 during the second mode of operation as part of the method 100. The method 100 is particularly configured to perform diagnostics such that the compensated operating parameters 54 and the accompanying first mode of operation are not affected. In other words, the method 100 is configured to reduce the impact of learning to compensate for the diagnostic observation of the operating parameters of one component 40 on the operating parameters of another component 40 without adversely affecting the performance of the subject component when the first operating mode goal is achieved.