阅读说明：本技术 一种燃料电池发动机能量管理系统的控制方法 (Control method of fuel cell engine energy management system ) 是由 胡钱坤 周鸿波 郭志阳 陆建山 于 2020-06-28 设计创作，主要内容包括：本发明涉及一种燃料电池发动机能量管理系统的控制方法,该系统包括燃料电池发动机、燃料电池发动机控制器、电压转换模块、电动机、动力电池、动力电池控制单元、能量管理单元和整车控制器,能量管理单元获取车辆实际需求功率,能量管理单元获取发动机输出功率,能量管理单元如下策略调整燃料电池发动机的工作档位：将能量管理单元控制逻辑中所允许的动力电池最大输出功率设为耗电功率；能量管理单元控制逻辑中所允许的动力电池充电功率设为充电功率；能量管理单元分析是否处于的区间内,根据所处的区间值,控制动力电池与燃料电池发动机配合,本发明的方法使得动力系统既能满足变化频繁的动态工况,又能满足长时间的稳定工况。(The invention relates to a control method of a fuel cell engine energy management system, which comprises a fuel cell engine, a fuel cell engine controller, a voltage conversion module, a motor, a power battery control unit, an energy management unit and a vehicle control unit, wherein the energy management unit acquires the actual required power of a vehicle The energy management unit obtains the output power of the engine The energy management unit adjusts the working gear of the fuel cell engine according to the following strategies: setting the maximum output power of the power battery allowed in the control logic of the energy management unit as power consumption power; the charging power of the power battery allowed in the energy management unit control logic is set as charging power; energy management unit analysis Whether or not to be in In the interval according to The interval value controls the power battery to be matched with the fuel cell engine, and the method of the invention ensures that the power system can not only meet the dynamic working condition with frequent change, but also meet the stable working condition for a long time.)

1. The control method of the fuel cell engine energy management system is characterized in that the system comprises a fuel cell engine, a fuel cell engine controller, a voltage conversion module, a motor, a power battery control unit and energy managementThe unit and the vehicle control unit are used for acquiring the actual required power of the vehicle through the vehicle control unitThe energy management unit obtains the output power of the engine through a fuel cell engine controllerThe energy management unit adjusts the working gear of the fuel cell engine by the following energy management stage control strategy:

firstly, setting the maximum output power of a power battery allowed in the control logic of an energy management unit as power consumption power; the charging power of the power battery allowed in the energy management unit control logic is set as charging power;

second, the energy management unit analyzesWhether or not to be inIn the interval of (a) to (b),

if it isAt the position ofIn the interval, the current working gear of the fuel cell engine is kept;

if it isLowering the working gear of the fuel cell engine; and inDuring the reduction stage, the energy management unit controls the unit through the power batteryThe power battery is switched to a charging state to receive rich power；

If it isThe working gear of the fuel cell engine is lifted; and is inIn the rising stage, the energy management unit enables the power battery to be switched into a power consumption state through the power battery control unit, and the power battery control unit provides power for the motorMagnitude of power.

2. The control method of a fuel cell engine energy management system according to claim 1, characterized in that the time interval for switching the fuel cell engine between the gear stages is set to beThe running time interval of the energy management stage control strategy is。

3. The control method of the fuel cell engine energy management system according to claim 1, wherein the energy management unit further comprises a power battery energy control strategy, and the specific process is as follows:

setting an upper limit value of the SOC value of the power battery as the SOC_upThe lower limit value is recorded as SOC_lowWhen the energy management unit is initialized, the power consumption power of the power battery is 0, the charging power is positive, and the energy management stage control strategy is carried outThe energy management unit enables the fuel cell engine to output powerIs limited toThe power battery is in a charging state;

raising the SOC value of the power battery to SOC_upAfter the above, the energy management unit makes the charging power of the power battery be 0 and the power consumption be positive, thereby limiting the output power of the fuel cell engine to be limitedThe power battery is in a discharging state;

the SOC value of the power battery is reduced to SOC_lowAfter that, the energy management unit makes the power consumption power of the power battery be 0 again, the charging power be a positive number, and the power battery is in a charging state again; the energy management unit manages the SOC value of the power battery to the reciprocating mode until the SOC value is always in [ SOC ]_low , SOC_up]Within the interval.

4. The method of claim 1, wherein the energy management unit further comprises a fuel cell engine activation phase control strategy, which comprises the following steps:

before the control strategy is operated in the energy management stage, the energy management unit preferentially enables the fuel cell engine to enter the maximum power gear for operating for a period of time, and the period of time is called as the activation stage of the fuel cell engine;

the energy management unit receives the SOC value of the power battery, sets the maximum allowable power content SOCmax of the power battery under the strategy, compares the minimum allowable power content SOCmin of the power battery with the current SOC value of the power battery, and if the current SOC value exceeds the SOCmin, the energy management unit improves a fuel cell engine controller to enable a fuel cell engine to be in a non-working state, and only the power battery works to reduce the SOC value of the power battery;

when the SOC value of the power battery is lower than the SOCmin, the energy management unit enables the fuel battery engine to work at the maximum power gear through the fuel battery engine controller;

when the fuel cell engine is in the maximum power gear and outputs the maximum power, the power cell is in a charging state, and when the real-time SOC value of the power cell reaches SOCmax, or the running time exceeds X minutes, the energy management unit ends the activation stage of the fuel cell engine and enters an energy management stage control strategy, wherein the value of X is 5-20.

5. The control method of the fuel cell engine energy management system according to claim 4, wherein in the control strategy of the fuel cell engine activation stage, the energy management unit records the maximum value of the power generated by the fuel cell engine in the maximum power gear, compares the maximum value with the ideal output power Pmax under the maximum power gear calibrated in advance, determines that the performance of the fuel cell engine is seriously attenuated if the maximum value of the power of the fuel cell engine in the maximum power gear is less than ɧ% of the Pmax, reports the data to the vehicle controller ɧ, and the value of the data is 80-93.

Technical Field

The invention relates to the field of fuel cell engines, in particular to a control method of an energy management system of a fuel cell engine.

Background

Most hydrogen fuel cell vehicles employ a fuel cell engine in electrical hybrid mode with a power cell, as shown in fig. 1. A power system for driving an electric motor by simultaneously operating a fuel cell engine and a power cell. The fuel cell engine is used as a main power output component, and due to the working principle that the fuel cell engine generates voltage and current by using an electrochemical reaction, the overall power response rate of the fuel cell engine is influenced by the dynamic response characteristic of self-establishing an equilibrium state and the response characteristic of an auxiliary system, so that the fuel cell engine cannot respond to the power demand which changes rapidly. The power battery is used as an auxiliary power output part, has good power response characteristics, can just make up for the defects of a fuel cell engine, and is used for responding to rapid power change.

In the system, because stepless response power change cannot be well realized due to the working principle of the fuel cell engine, the output power of the fuel cell engine is artificially divided into a plurality of gears, the power difference of each gear is kept within 5kw (after the technology is improved, the power difference of each gear can be controlled to be smaller), each gear corresponds to the working parameters of the fuel cell engine, the different working parameters of the different gears are stable working states obtained in advance in the engine calibration stage, and how to enable the power cell and the fuel cell engine to work better in a matched mode is a technical problem which needs to be solved urgently by a person skilled in the art.

Disclosure of Invention

In order to solve the above technical problems, an object of the present invention is to provide a control method for an energy management system of a fuel cell engine, which enables a power system to satisfy both a dynamic condition with frequent changes and a stable condition for a long time.

In order to achieve the first object, the invention adopts the following technical scheme:

a control method of a fuel cell engine energy management system comprises a fuel cell engine, a fuel cell engine controller, a voltage conversion module, a motor, a power battery control unit, an energy management unit and a vehicle control unit, wherein the energy management unit acquires the actual required power of a vehicle through the vehicle control unitThe energy management unit obtains the output power of the engine through a fuel cell engine controllerThe energy management unit adjusts the working gear of the fuel cell engine by the following energy management stage control strategy:

firstly, setting the maximum output power of a power battery allowed in the control logic of an energy management unit as power consumption power; the charging power of the power battery allowed in the energy management unit control logic is set as charging power;

second, energy managementUnit analysisWhether or not to be inIn the interval of (a) to (b),

if it isAt the position ofIn the interval, the current working gear of the fuel cell engine is kept;

if it isLowering the working gear of the fuel cell engine; and inIn the lowering stage, the energy management unit switches the power battery into a charging state through the power battery control unit and receives abundant power；

If it isThe working gear of the fuel cell engine is lifted; and is inIn the rising stage, the energy management unit enables the power battery to be switched into a power consumption state through the power battery control unit, and the power battery control unit provides power for the motorMagnitude of power.

Preferably, the fuel cell engine is arranged at each gearThe time interval of inter-switching is set asThe running time interval of the energy management stage control strategy is。

As a preferred scheme, the energy management unit further comprises a power battery energy control strategy, and the specific process is as follows:

setting an upper limit value of the SOC value of the power battery as the SOC_upThe lower limit value is recorded as SOC_lowWhen the energy management unit is initialized, the power consumption power of the power battery is 0, the charging power is positive, and when the energy management stage control strategy is carried out, the energy management unit enables the fuel cell engine to output powerIs limited toThe power battery is in a charging state;

raising the SOC value of the power battery to SOC_upAfter the above, the energy management unit makes the charging power of the power battery be 0 and the power consumption be positive, thereby limiting the output power of the fuel cell engine to be limitedThe power battery is in a discharging state;

the SOC value of the power battery is reduced to SOC_lowAfter that, the energy management unit makes the power consumption power of the power battery be 0 again, the charging power be a positive number, and the power battery is in a charging state again; the energy management unit manages the SOC value of the power battery to the reciprocating mode until the SOC value is always in [ SOC ]_low , SOC_up]Within the interval.

Preferably, the energy management unit further comprises a fuel cell engine activation phase control strategy, and the specific process is as follows:

before the control strategy is operated in the energy management stage, the energy management unit preferentially enables the fuel cell engine to enter the maximum power gear for operating for a period of time, and the period of time is called as the activation stage of the fuel cell engine;

the energy management unit receives the SOC value of the power battery, sets the maximum allowable power content SOCmax of the power battery under the strategy, compares the minimum allowable power content SOCmin of the power battery with the current SOC value of the power battery, and if the current SOC value exceeds the SOCmin, the energy management unit improves a fuel cell engine controller to enable a fuel cell engine to be in a non-working state, and only the power battery works to reduce the SOC value of the power battery;

when the SOC value of the power battery is lower than the SOCmin, the energy management unit enables the fuel battery engine to work at the maximum power gear through the fuel battery engine controller;

when the fuel cell engine is in the maximum power gear and outputs the maximum power, the power cell is in a charging state, and when the real-time SOC value of the power cell reaches SOCmax, or the running time exceeds X minutes, the energy management unit ends the activation stage of the fuel cell engine and enters an energy management stage control strategy, wherein the value of X is 5-20.

Preferably, in a control strategy of a fuel cell engine activation stage, an energy management unit records a maximum value of power generated by the fuel cell engine at a maximum power gear, compares the maximum value with an ideal output power Pmax at the maximum power gear of the fuel cell engine calibrated in advance, judges that the performance of the fuel cell engine is seriously attenuated if the maximum value of the power of the fuel cell engine at the maximum power gear is smaller than ɧ% of the Pmax, reports the data to a vehicle control unit, and the value ɧ is 80-93.

Compared with the prior art, the invention has the beneficial effects that: in the method, the real-time power requirement, the fuel cell engine state and the power battery state of the vehicle are acquired by the energy management unit during the running of the vehicle, and the power output of the fuel cell engine and the power battery is distributed, so that the power system can meet the dynamic working condition with frequent change and the stable working condition for a long time. Meanwhile, the power battery is regulated to be in the optimal working state by limiting the power output interval of the fuel battery engine. The working efficiency of the fuel cell engine during the running period of the subsequent vehicle is improved by controlling the fuel cell engine to work at high power in advance.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the application and, together with the description, serve to explain the application and are not intended to limit the application.

FIG. 1 is a schematic diagram of the system architecture of the present invention;

FIG. 2 is a schematic diagram of the control principle of the present invention;

FIG. 3 is a flow diagram of an energy management phase control strategy of the present invention;

FIG. 4 is a schematic flow chart of the fuel cell engine activation phase control strategy of the present invention;

FIG. 5 is a schematic diagram showing the variation of the vehicle power demand, the fuel cell engine power and the power cell SOC at each stage of the energy management unit operation of the present invention.

Detailed Description

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, elements, and/or combinations thereof, unless the context clearly indicates otherwise.

Further, in the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, unless otherwise specified, "a plurality" means two or more unless explicitly defined otherwise.

In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

The invention will be further illustrated with reference to the following examples and drawings:

the present embodiment provides a control method of an energy management system of a fuel cell engine, as shown in fig. 1 and fig. 2, the system includes a fuel cell engine, a fuel cell engine controller, a voltage conversion module, an electric motor, a power battery control unit, an energy management unit and a vehicle control unit, where the energy management unit obtains an actual required power of a vehicle through the vehicle control unitThe energy management unit obtains the output power of the engine through a fuel cell engine controllerThe energy management unit adjusts the operating range of the fuel cell engine by the following energy management phase control strategy, as shown in fig. 3:

firstly, setting the maximum output power of a power battery allowed in the control logic of an energy management unit as power consumption power; the charging power of the power battery allowed in the energy management unit control logic is set as charging power;

second, the energy management unit analyzesWhether or not to be inWithin the interval of (A), ifAt the position ofIn the interval of (2), the fuel cell is kept startedThe current working gear of the machine; if it isLowering the working gear of the fuel cell engine; in thatAt the stage of lowering, becauseThe response lag of the energy management unit leads to the existence of power surplus phenomenon of the whole vehicle, and the energy management unit controls the power battery to be switched into a charging state to receive surplus energy(ii) a If it isThe working gear of the fuel cell engine is lifted; at the same time, inAt the rising stage, due toThe response of the energy management unit is delayed, so that the power shortage phenomenon exists in the whole vehicle, and the energy management unit controls the power battery to supply power to the power batteryMagnitude of power output.

When the energy management unit compares, analyzes and adjusts the working gear of the fuel cell engine and the working state of the power cell in real time, because the switching time of the fuel cell engine between different gears is certainly longer than the real-time judgment period of the energy management unit, which causes the gear analyzed by the energy management unit to be changed less than expected, the energy management unit should perform the next comparison analysis and adjustment work after the gear of the fuel cell engine is switched, and the energy management unit can calibrate the working gear of the fuel cell engine in advance according to the preset valueObtaining the time interval for the fuel cell engine to switch between gearsSetting a delay time after switching gears for the energy management unitSo as to eliminate the problem of continuous change of gears. I.e. the run-time interval of the energy management phase control strategy is。

The energy management unit further comprises a power battery energy control strategy, and the specific process is as follows: setting an upper limit value of the SOC value of the power battery as the SOC_upThe lower limit value is recorded as SOC_lowWhen the energy management unit is initialized, the power consumption power of the power battery is 0, the charging power is positive, and when the energy management stage control strategy is carried out, the energy management unit enables the fuel cell engine to output powerIs limited toThe power battery is in a charging state; raising the SOC value of the power battery to SOC_upAfter the above, the energy management unit makes the charging power of the power battery be 0 and the power consumption be positive, thereby limiting the output power of the fuel cell engine to be limitedThe power battery is in a discharging state; the SOC value of the power battery is reduced to SOC_lowAfter that, the energy management unit makes the power consumption power of the power battery be 0 again, the charging power be a positive number, and the power battery is in a charging state again; the energy management unit manages the SOC value of the power battery to the reciprocating mode until the SOC value is always in [ SOC ]_low , SOC_up]Within the interval. By the method, the power battery is stabilized in a certain interval, the working efficiency of the power battery is improved, and the service life of the power battery is prolonged.

As shown in fig. 4, in order to quickly bring the fuel cell engine into the optimal working state, the energy management unit further includes a fuel cell engine activation phase control strategy, and specifically, before the energy management phase control strategy is operated, the energy management unit preferentially brings the fuel cell engine into the maximum power gear for a period of time, which is called the fuel cell engine activation phase;

the energy management unit receives the SOC value of the power battery, sets the maximum allowable power content SOCmax of the power battery under the strategy, compares the minimum allowable power content SOCmin of the power battery with the current SOC value of the power battery, and if the current SOC value exceeds the SOCmin, the energy management unit improves a fuel cell engine controller to enable a fuel cell engine to be in a non-working state, and only the power battery works to reduce the SOC value of the power battery;

when the SOC value of the power battery is lower than the SOCmin, the energy management unit enables the fuel battery engine to work at the maximum power gear through the fuel battery engine controller;

when the fuel cell engine is in the maximum power gear and outputs the maximum power, the power battery is in a charging state, and when the real-time SOC value of the power battery reaches SOCmax, or the running time exceeds X minutes (the value of X is 5-20), the energy management unit ends the activation stage of the fuel cell engine and enters an energy management stage control strategy.

The dynamic response rate of the fuel cell engine can be improved through the control strategy of the activation stage of the fuel cell engine, the working efficiency of the fuel cell engine at each gear can also be improved, and the endurance mileage of the vehicle is increased.

In a control strategy of a fuel cell engine in an activation stage, an energy management unit records the maximum value of power generated by the fuel cell engine in a maximum power gear, compares the maximum value with ideal output power Pmax under the maximum power gear of the fuel cell engine calibrated in advance, judges that the performance of the fuel cell engine is seriously attenuated if the maximum value of the power of the fuel cell engine in the maximum power gear is smaller than ɧ% of the Pmax (the value of ɧ is 80-93), and reports the condition to a vehicle control unit to inform a driver of the service life of the fuel cell engine.

Referring to fig. 5, a specific operation process of the energy management unit is illustrated:

and in the stage 0-t1, the vehicle is not operated.

And (4) at stage t1-t2, the vehicle runs, the energy management unit starts to work, the route a in the figure 4 is entered, the fuel cell engine activation stage is checked to be not run, the route c in the figure 4 is entered, the power battery SOC is checked to be larger than SOCmin, the route e-j-a in the figure 4 is entered, and then the cycle judgment is carried out. In the stage, the power battery continuously responds to the power required by the whole vehicle, and the SOC of the power battery continuously decreases.

And in the period from t2 to t4, the energy management unit checks that the SOC of the power battery is less than or equal to SOCmin through a path c in the graph in FIG. 4, and enters a path d-f-h in the graph in FIG. 4, and the energy management unit enters the activation stage of the fuel cell engine and controls the fuel cell engine to work to the maximum power gear (wherein the period from t2 to t3 represents the process that the fuel cell engine directly works to the maximum working gear). Then, it is determined that the power cell SOC is less than SOCmax and that the fuel cell engine is operating in the maximum power gear for no more than 5 to 20 minutes. And the energy management unit enters an i-f-h loop for judgment. In the stage, the power battery is in a charging state because the power of the engine of the fuel battery is larger than the power required by the whole vehicle, and the SOC of the power battery is continuously increased.

At stage t4-t5, the energy management unit checks that the SOC of the power battery is greater than or equal to the SOCmax, enters a path g-a in fig. 4, and determines that the fuel cell engine has already been operated in the activation stage, thereby entering a path b in fig. 4, determines that the maximum power value of the fuel cell engine at the maximum power level (corresponding to the time period t3-t 4) is less than ɧ% of Pmax, and the energy management unit reports that the performance of the fuel cell engine is seriously degraded, and finally enters the energy management stage.

Thereby to obtainThe energy management unit enters the path a-b-c-d of fig. 3 due to fuel cell engine powerIs more than the power demand of the whole vehicle+ charging power (note that at this time, since the SOC of the power battery is greater than SOCup, the charging power is 0), the energy management unit enters a path h-j of fig. 3, starts to lower the operating range of the fuel cell engine, and due to the delay timeThe fuel cell engine has a smooth and tiny time period after the first gear is reduced.

During the t5-t6 phases, the energy management units all operate under the paths a-b-c-d-e-g-a of FIG. 3. At the moment, because the power of the fuel cell engine is smaller than the power required by the whole vehicle, the power cell is in a discharging state, and the SOC value of the power cell is continuously reduced.

In the stage of t6-t7, the power required by the whole vehicle is changed, and the power management unit checks the power of the fuel cell engineIs less than the power demand of the whole vehicle-power consumption, entering path k-a-b-c-d-f-i-k in fig. 3, continuously raising the operating range of the fuel cell engine due to the delay timeThe fuel cell engine has a stable micro time period after the first gear is lifted.

At the stage t7-t8, the SOC of the power battery is detected to be reduced to the SOC by the energy management unit_lowHereinafter, the charging power is adjusted to a positive number (originally 0), and the power consumption is adjusted to 0 (originally positive). Energy managementAfter the unit has entered path d of FIG. 3, the fuel cell engine power is checkedIs less than the power required by the whole vehicleConsuming power and thus going into path f-h-j of fig. 3, raising the fuel cell engine gear by 1.

After t8, if the required power of the whole vehicle is not changed any more, the energy management unit is operated in a-b-c-d-e-g-a of fig. 3.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and not to be construed as limiting the present invention, and those skilled in the art can make changes, modifications, substitutions and alterations to the above embodiments without departing from the principle and spirit of the present invention, and any simple modification, equivalent change and modification made to the above embodiments according to the technical spirit of the present invention still fall within the technical scope of the present invention.