Energy management method for fuel cell vehicle and fuel cell vehicle

Abstract

The invention relates to the technical field of vehicles, and discloses an energy management method of a fuel cell vehicle and the fuel cell vehicle, the energy management method of the fuel cell vehicle needs to judge whether an initial SOC value is smaller than an initial preset SOC value or not, if yes, a fuel cell engine is started, and if not, the fuel cell engine is not started. Secondly, in the heavy load state, when the real-time SOC value is increased to the first preset SOC value and kept for the first preset time, the fuel cell engine is turned off, and when the real-time SOC value is reduced to the second preset SOC value and kept for the second preset time, the fuel cell engine is started. And in the light load state, when the real-time SOC value is increased to a third preset SOC value, the fuel cell engine is shut down, and when the real-time SOC value is reduced to a fourth preset SOC value, the fuel cell engine is started. The light load and the heavy load are distinguished, and the SOC preset value and the preset time are combined, so that the start-stop times and the high-power working probability of the fuel cell can be reduced, and the service life is prolonged.

Description

Technical Field

[0001] The present invention relates to the field of vehicle technology, and in particular to an energy management method for a fuel cell vehicle and a fuel cell vehicle. Background Art

[0002] In the energy management method of fuel cell vehicles, the size of the power request is greatly affected by the vehicle load. At present, power allocation is mainly dynamically controlled according to the SOC (State of Charge) of the power battery. This method can ensure that the power battery will not be overcharged or over-discharged to a certain extent, and can also meet the power demand to a certain extent. However, if the SOC of the power battery changes greatly, the fuel cell may operate at a higher power, and may frequently change load, or even start and stop frequently, which not only reduces the economy of the fuel cell, but also affects its service life.

[0003] Therefore, there is an urgent need for an energy management method for a fuel cell vehicle and a fuel cell vehicle to solve the above problems. Summary of the invention

[0004] One object of the present invention is to provide an energy management method for a fuel cell vehicle, which can solve the problem of accelerated system attenuation caused by the fuel cell working under high power or variable load conditions for a long time and increase the service life of the fuel cell.

[0005] As conceived above, the technical solution adopted by the present invention is:

[0006] An energy management method for a fuel cell vehicle controls the operation of a power battery and a fuel cell engine connected to each other in the fuel cell vehicle according to the total power demand of the fuel cell vehicle, and the energy management method for the fuel cell vehicle comprises:

[0007] S0: In the power battery driving state, the initial SOC value Mc of the power battery is obtained, and it is determined whether the initial SOC value Mc is less than the initial preset SOC value M. If so, the fuel cell engine is started, and if not, the fuel cell engine is not started;

[0008] When a fuel cell vehicle is running under heavy load, the following steps are performed:

[0009] S11: If the fuel cell engine is started, the real-time SOC value Ms of the power battery is continuously obtained, and when the real-time SOC value Ms increases to a first preset SOC value M1 and is maintained for a first preset time t1, the fuel cell engine is turned off, M1 ≥ M;

[0010] S12: If the fuel cell engine is not started, continue to obtain the real-time SOC value Ms of the power battery, and when the real-time SOC value Ms decreases to a second preset SOC value M2 and is maintained for a second preset time t2, start the fuel cell engine, M2<M;

[0011] When the fuel cell vehicle is running under light load, perform the following steps:

[0012] S21: if the fuel cell engine is started, continue to obtain the real-time SOC value Ms of the power battery, and when the real-time SOC value Ms increases to a third preset SOC value M3, shut down the fuel cell engine, M3 ≥ M;

[0013] S22: If the fuel cell engine is not started, continue to obtain the real-time SOC value Ms of the power battery, and when the real-time SOC value Ms decreases to a fourth preset SOC value M4, start the fuel cell engine, M4<M.

[0014] Optionally, when the fuel cell vehicle is in a heavy load state, the operating power of the fuel cell engine is set to Pz, and when the fuel cell vehicle is in a light load state, the operating power of the fuel cell engine is set to Pq, where Pz>Pq.

[0015] Optionally, M1>M>M2, M3>M>M4.

[0016] Optionally, M1=M3, M2=M4.

[0017] Optionally, t1≥3min, t2≥3min.

[0018] Optionally, t1=t2.

[0019] Another object of the present invention is to provide a fuel cell vehicle that can solve the problem of accelerated system attenuation caused by the fuel cell operating under high power or variable load conditions for a long time, thereby increasing the service life of the fuel cell.

[0020] As conceived above, the technical solution adopted by the present invention is:

[0021] A fuel cell vehicle applies the above-mentioned energy management method for a fuel cell vehicle.

[0022] Optionally, the fuel cell vehicle includes a vehicle controller, a fuel cell controller, a fuel cell engine, a power battery manager, a power battery, a drive motor controller and a drive motor;

[0023] The vehicle controller is communicatively connected with the fuel cell controller, the power battery manager and the drive motor controller respectively, so that the drive motor controller can manage the drive motor according to the vehicle requirements of the fuel cell vehicle, the power battery manager can manage the power battery according to the vehicle requirements of the fuel cell vehicle, and the fuel cell controller can manage the fuel cell engine according to the vehicle requirements of the fuel cell vehicle.

[0024] Optionally, the fuel cell vehicle further includes an instrument, which is electrically connected to the vehicle controller, and is used to receive a load signal of the fuel cell vehicle, wherein the load signal is used to indicate whether the fuel cell vehicle is in a heavy load state or a light load state.

[0025] Optionally, the vehicle controller is used to obtain the total required power of the fuel cell vehicle according to the accelerator pedal opening and climbing grade of the fuel cell vehicle.

[0026] The beneficial effects of the present invention are:

[0027] The energy management method of the fuel cell vehicle proposed in the present invention first obtains the initial SOC value Mc of the power battery in the power battery driving state, determines whether the initial SOC value Mc is less than the initial preset SOC value M, and if so, starts the fuel cell engine, otherwise, does not start the fuel cell engine. Then the fuel cell vehicle runs in a heavy load state, and performs the following steps: S11: If the fuel cell engine is started, continue to obtain the real-time SOC value Ms of the power battery, and when the real-time SOC value Ms increases to the first preset SOC value M1 and maintains the first preset time t1, turn off the fuel cell engine, M1≥M; S12: If the fuel cell engine is not started, continue to obtain the real-time SOC value Ms of the power battery, and when the real-time SOC value Ms decreases to the second preset SOC value M2 and maintains the second preset time t2, start the fuel cell engine, M2≤M. When the vehicle is running under light load, the following steps are performed: S21: if the fuel cell engine is started, the real-time SOC value Mc of the power battery is continuously obtained, and when the real-time SOC value Mc increases to the third preset SOC value M3, the fuel cell engine is turned off, M3≥M; S22: if the fuel cell engine is not started, the real-time SOC value Mc of the power battery is continuously obtained, and when the real-time SOC value Mc decreases to the fourth preset SOC value M4, the fuel cell engine is started, M4≤M. The energy management method of the fuel cell vehicle can minimize the number of starts and stops of the fuel cell and the probability of working at high power, on the premise of distinguishing the light load and heavy load states of the fuel cell vehicle, combined with the setting of the SOC preset value and the preset time, thereby increasing the service life of the fuel cell.

[0028] The fuel cell vehicle proposed in the present invention applies the above-mentioned energy management method for fuel cell vehicles, which can solve the problem of accelerated system attenuation caused by the fuel cell working under high power or variable load conditions for a long time, thereby increasing the service life of the fuel cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a flow chart of an energy management method for a fuel cell vehicle provided by an embodiment of the present invention;

[0030] Figure 2 A schematic diagram of the control system architecture of a fuel cell vehicle provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0031] In order to make the technical problems solved by the present invention, the technical solutions adopted and the technical effects achieved clearer, the technical solutions of the present invention are further described below in conjunction with the accompanying drawings and through specific implementation methods. It is understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for the convenience of description, only the parts related to the present invention are shown in the accompanying drawings, not all.

[0032] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0034] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0035] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0036] Fuel cell vehicles have two power sources, fuel cells and power batteries. During the driving process of the fuel cell vehicle, the vehicle controller can allocate the work of the fuel cell and the power battery according to the vehicle load signal and the power battery SOC value provided by the power battery manager. And because different loads have different changes in the power battery SOC value and the requirements for the fuel cell, the energy management method for the fuel cell vehicle provided in this embodiment controls the work of the interconnected power battery and the fuel cell engine in the fuel cell vehicle according to the total power demand of the fuel cell vehicle under the premise of distinguishing between light load and heavy load, so as to minimize the number of starts and stops of the fuel cell and the probability of working at high power, thereby increasing the service life of the fuel cell.

[0037] Specifically, S0: in the power battery driving state, obtaining the initial SOC value Mc of the power battery, judging whether the initial SOC value Mc is less than the initial preset SOC value M, if so, starting the fuel cell engine, if not, not starting the fuel cell engine;

[0038] When a fuel cell vehicle is running under heavy load, the following steps are performed:

[0039] S11: If the fuel cell engine is started, the real-time SOC value Ms of the power battery is continuously obtained, and when the real-time SOC value Ms increases to a first preset SOC value M1 and is maintained for a first preset time t1, the fuel cell engine is turned off, M1 ≥ M;

[0040] S12: If the fuel cell engine is not started, continue to obtain the real-time SOC value Ms of the power battery, and when the real-time SOC value Ms decreases to a second preset SOC value M2 and is maintained for a second preset time t2, start the fuel cell engine, M2<M;

[0041] When the fuel cell vehicle is running under light load, perform the following steps:

[0042] S21: if the fuel cell engine is started, continue to obtain the real-time SOC value Ms of the power battery, and when the real-time SOC value Ms increases to a third preset SOC value M3, shut down the fuel cell engine, M3 ≥ M;

[0043] S22: If the fuel cell engine is not started, continue to obtain the real-time SOC value Ms of the power battery, and when the real-time SOC value Ms decreases to a fourth preset SOC value M4, start the fuel cell engine, M4<M.

[0044] Preferably, t1≥3min, t2≥3min. Setting a suitable preset time can not only ensure the power demand of the whole vehicle, but also avoid frequent switching of the fuel cell, thereby ensuring the economy and service life of the fuel cell.

[0045] Preferably, t1=t2.

[0046] Furthermore, in order to meet the power requirements of fuel cell vehicles under different loads, that is, when the SOC of the power battery is low, the fuel cell engine can be requested to work at a high power output so as to replenish the SOC while driving the fuel cell vehicle. In the energy management method for fuel cell vehicles provided in this embodiment, the operating power setting values ​​of the fuel cell engine of the fuel cell vehicle under heavy load and light load are also different. When the fuel cell vehicle is under heavy load, the operating power of the fuel cell engine is set to Pz, and when the fuel cell vehicle is under light load, the operating power of the fuel cell engine is set to Pq, and Pz>Pq.

[0047] Preferably, Pz≤100kw, Pq≤80kw. Appropriate operating power can ensure the power demand of the whole vehicle and avoid the fuel cell working under high power conditions for a long time and affecting its life.

[0048] In addition, in order to further avoid frequent start-up and shutdown of the fuel cell engine and ensure the service life of the fuel cell, M1>M>M2, that is, when the fuel cell vehicle is under heavy load, the fuel cell engine can only be restarted when the real-time SOC value Ms of the power battery decreases to a value lower than the initial preset SOC value M and is maintained for the second preset time t2, and the fuel cell engine can only be shut down when the real-time SOC value Ms of the power battery increases to a value higher than the initial preset SOC value and is maintained for the first preset time t1. Among them, setting the first preset SOC value M1 to be greater than the initial preset SOC value M, the second preset SOC value M2 to be less than the preset SOC value M, and limiting it to be maintained for a preset time in the corresponding state are all to avoid frequent start-up and shutdown of the fuel cell engine.

[0049] Similarly, M3>M>M4, that is, when the fuel cell vehicle is in a light load state, the fuel cell engine can be restarted only when the real-time SOC value Ms of the power battery drops to a value lower than the initial preset SOC value M, and the fuel cell engine can be shut down only when the real-time SOC value Ms of the power battery rises to a value higher than the initial preset SOC value.

[0050] Preferably, M1=M3, M2=M4.

[0051] Preferably, the value range of the initial preset value M, the first preset value M1, the second preset value M2, the third preset value M3 and the fourth preset value M4 is 69%<M<71%, and 72%<M1<78%, 37%<M2<43%, 72%<M3<78%, and 37%<M4<43%.

[0052] Energy management method reference for fuel cell vehicles Figure 1 The process shown is executed, and the above specific values ​​are not fixed for different models and need to be fine-tuned according to the battery characteristics of different models. In this embodiment, M1 = 75%, M2 = 40%, M3 = 75%, M4 = 40%, t1 = t2 = 3min, Pz = 100kw, Pq = 80kw.

[0053] If the vehicle is heavily loaded, the SOC change may be more drastic, and the maximum requested power of the fuel cell engine will be higher to meet the needs of the entire vehicle.

[0054] When the initial SOC value Mc>70%, the fuel cell engine is not requested to start, and the power required by the vehicle is provided by the power battery. To avoid frequent power changes under heavy load conditions, the fuel cell engine can be requested to start again only when the real-time SOC value Ms drops to 40% and exceeds 3 minutes, and the maximum value of the fuel cell engine request power is 100kw.

[0055] When the initial SOC value Mc<70%, the fuel cell engine is requested to start, and the maximum power requested by the fuel cell engine is 100kw. To avoid frequent power changes under heavy load conditions, the fuel cell engine can be shut down only when the real-time SOC value Ms rises to 75% and exceeds 3 minutes.

[0056] If the load is light, the SOC change may be relatively smooth, and the maximum requested power of the fuel cell engine can be appropriately reduced to reduce the high-power operating time of the fuel cell engine and enhance durability.

[0057] When the initial SOC value Mc>70%, the fuel cell engine is not requested to start, and the power required by the vehicle is provided by the power battery. When the real-time SOC value Ms decreases to 40%, the fuel cell engine can be requested to start again, and the maximum power requested by the fuel cell engine is 80kw.

[0058] When the initial SOC value Mc<70%, the fuel cell engine is requested to start, and the maximum power requested by the fuel cell engine is 80kw. The fuel cell engine can be shut down only when the real-time SOC value Ms increases to 75%.

[0059] The vehicle energy management method provided in this embodiment can maximize the service life of the fuel cell system by optimizing the software model and control method without adding complex algorithms, without causing major changes to the fuel cell and the vehicle hardware.

[0060] The present embodiment also provides a fuel cell vehicle. By applying the above-mentioned energy management method for the fuel cell vehicle, the problem of accelerated system attenuation caused by the fuel cell working under high power or variable load conditions for a long time can be solved, thereby increasing the service life of the fuel cell.

[0061] like Figure 2 As shown, optionally, the fuel cell vehicle includes a vehicle controller, a fuel cell controller, a power battery manager, a drive motor controller, a fuel cell engine, a power battery and a drive motor. The vehicle controller is respectively connected to the fuel cell controller, the power battery manager and the drive motor controller, wherein the fuel cell controller can manage the fuel cell engine according to the vehicle requirements of the fuel cell vehicle, the power battery manager can manage the power battery according to the vehicle requirements of the fuel cell vehicle, and the drive motor controller can manage the drive motor according to the vehicle requirements of the fuel cell vehicle.

[0062] In specific implementation, the fuel cell controller is used to dynamically monitor the state of the fuel cell stack, and the power battery manager is used to dynamically monitor the state of the power battery. Both are connected to the vehicle controller of the fuel cell vehicle through the CAN bus of the automobile network to receive or feedback the signals sent by the fuel cell controller and the power battery manager. When the fuel cell vehicle is running, the vehicle controller uses the energy management method of the fuel cell vehicle described above to optimally allocate the energy of the fuel cell and the power battery. It should be noted that in this embodiment, the energy management method of the fuel cell vehicle used by the fuel cell vehicle only indicates the "SOC condition", that is, the SOC value of the power battery obtained by the power battery manager is fed back to the vehicle controller, and the vehicle controller uses the "SOC condition" as one of the obtained operation information, and then combines the other operation information such as vehicle speed and environmental information to manage and allocate the energy of the fuel cell and power battery of the fuel cell vehicle.

[0063] The fuel cell vehicle also includes a DC / DC converter electrically connected to the fuel cell engine and the power battery. The DC / DC converter can better control the voltage or current of the fuel cell and the power battery so that their voltage no longer needs to match the bus voltage. The power battery and the fuel cell are also electrically connected to the drive motor controller through the high-voltage bus so that the fuel cell and the power battery can power the drive motor.

[0064] Optionally, the fuel cell vehicle further includes an instrument, which is electrically connected to the vehicle controller, and is used to receive a load signal of the fuel cell vehicle, and the load signal is used to indicate whether the fuel cell vehicle is in a heavy load state or a light load state. In specific implementation, the driver can select a heavy load button or a light load button on the instrument according to the current load, so that the corresponding load signal is sent to the vehicle controller through the instrument, and when no selection is made, the fuel cell vehicle is assumed to be in a light load state.

[0065] Optionally, the vehicle controller is also used to obtain the total required power of the fuel cell vehicle based on the accelerator pedal opening and climbing grade of the fuel cell vehicle, so that the fuel cell vehicle can specifically allocate the power battery and / or fuel cell operation according to the energy management method of the fuel cell vehicle, thereby meeting the total required power of the fuel cell vehicle.

[0066] The above embodiments are only to illustrate the basic principles and characteristics of the present invention. The present invention is not limited by the above embodiments. Without departing from the spirit and scope of the present invention, the present invention may be subject to various changes and modifications, which are within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for energy management of a fuel cell vehicle, characterized in that: The operation of the power battery and the fuel cell engine connected to each other in the fuel cell vehicle is controlled according to the total power demand of the fuel cell vehicle, and the energy management method of the fuel cell vehicle includes: S0: In the power battery driving state, the initial SOC value Mc of the power battery is obtained, and it is determined whether the initial SOC value Mc is less than the initial preset SOC value M. If so, the fuel cell engine is started, and if not, the fuel cell engine is not started; When a fuel cell vehicle is running under heavy load, the following steps are performed: S11: If the fuel cell engine is started, the real-time SOC value Ms of the power battery is continuously obtained, and when the real-time SOC value Ms increases to a first preset SOC value M1 and is maintained for a first preset time t1, the fuel cell engine is turned off, M1 ≥ M; S12: If the fuel cell engine is not started, continue to obtain the real-time SOC value Ms of the power battery, and when the real-time SOC value Ms decreases to a second preset SOC value M2 and is maintained for a second preset time t2, start the fuel cell engine, M2<M; When the fuel cell vehicle is running under light load, perform the following steps: S21: if the fuel cell engine is started, continue to obtain the real-time SOC value Ms of the power battery, and when the real-time SOC value Ms increases to a third preset SOC value M3, shut down the fuel cell engine, M3 ≥ M; S22: If the fuel cell engine is not started, continue to obtain the real-time SOC value Ms of the power battery, and when the real-time SOC value Ms decreases to a fourth preset SOC value M4, start the fuel cell engine, M4<M.

2. The energy management method for a fuel cell vehicle according to claim 1, characterized in that: When the fuel cell vehicle is in a heavy load state, the operating power of the fuel cell engine is set to Pz, and when the fuel cell vehicle is in a light load state, the operating power of the fuel cell engine is set to Pq, where Pz>Pq.

3. The energy management method for a fuel cell vehicle according to claim 1, characterized in that: M1>M>M2, M3>M>M4.

4. The energy management method for a fuel cell vehicle according to claim 3, characterized in that: M1=M3, M2=M4.

5. The energy management method for a fuel cell vehicle according to claim 1, characterized in that: t1≥3min, t2≥3min.

6. The energy management method for a fuel cell vehicle according to claim 5, characterized in that: t1=t2.

7. A fuel cell vehicle, characterized in that: An energy management method for a fuel cell vehicle using any one of claims 1 to 6.

8. The fuel cell vehicle according to claim 7, characterized in that: The fuel cell vehicle comprises a vehicle controller, a fuel cell controller, a fuel cell engine, a power battery manager, a power battery, a drive motor controller and a drive motor; The vehicle controller is communicatively connected with the fuel cell controller, the power battery manager and the drive motor controller respectively, so that the drive motor controller can manage the drive motor according to the vehicle requirements of the fuel cell vehicle, the power battery manager can manage the power battery according to the vehicle requirements of the fuel cell vehicle, and the fuel cell controller can manage the fuel cell engine according to the vehicle requirements of the fuel cell vehicle.

9. The fuel cell vehicle according to claim 8, characterized in that: The fuel cell vehicle also includes an instrument, which is electrically connected to the vehicle controller and is used to receive a load signal of the fuel cell vehicle, wherein the load signal is used to indicate whether the fuel cell vehicle is in a heavy load state or a light load state.

10. The fuel cell vehicle according to claim 8, characterized in that: The vehicle controller is used to obtain the total required power of the fuel cell vehicle according to the accelerator pedal opening and climbing grade of the fuel cell vehicle.

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