A method and system for determining fuel cell power request based on vehicle operating speed

Abstract

This invention proposes a method and system for determining fuel cell power requests based on vehicle operating speed. By determining the current operating mode of the vehicle, when the vehicle is in hydrogen-electric operating mode and the power battery SOC is within a set threshold range, the method applies the current driving conditions of the vehicle, along with the average power demand of the fuel cell vehicle corresponding to the operating speed range of the previous cycle, to determine the fuel cell power request for the current cycle. This method determines the power request value based on the operating conditions, exhibiting high adaptability. Furthermore, it maximizes the direct utilization of the electricity generated by the fuel cell by the entire vehicle, avoiding energy conversion losses and improving the overall vehicle economy.

Description

Technical Field

[0001] This invention belongs to the field of hybrid vehicle technology, and particularly relates to a method and system for determining fuel cell power request based on vehicle operating speed. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] Currently, most fuel cell buses use electric-electric hybrid systems, where the power battery and fuel cell work together to power the electric motor and drive the vehicle. The power response of the fuel cell system to the vehicle's power demand is crucial, and the fuel cell system's economy and lifespan are closely related to the vehicle's power demand strategy. However, current vehicle hydrogen-electric hybrid energy management strategies struggle to simultaneously optimize both vehicle economy and fuel cell system lifespan. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, the present invention provides a method and system for determining fuel cell power request based on vehicle operating speed, so that the electricity generated by the fuel cell can be directly utilized by the whole vehicle to the maximum extent, avoiding energy conversion loss and improving the economy of the whole vehicle.

[0005] To achieve the above objectives, a first aspect of the present invention provides a method for determining fuel cell power request based on vehicle operating speed, comprising:

[0006] Determine whether the vehicle is currently in hydrogen-electric mode;

[0007] If the vehicle is currently in hydrogen-electric mode and the SOC of the power battery is within the set threshold range, then the current driving condition of the vehicle is determined.

[0008] Based on the vehicle's operating conditions, the current requested power of the fuel cell is determined by the effective value of the average power demand of the fuel cell in the speed range corresponding to the vehicle's previous power-on cycle.

[0009] A second aspect of the present invention provides a fuel cell power request determination system based on vehicle operating speed, comprising:

[0010] The first judgment module is configured to: determine whether the current vehicle is in hydrogen-electric working mode;

[0011] The second judgment module is configured to: if the current vehicle is in hydrogen-electric working mode and the power battery SOC is within a set threshold range, then determine the current driving condition of the vehicle.

[0012] The determination module is configured to: determine the current requested power of the fuel cell based on the effective value of the average power demand of the fuel cell in the speed range corresponding to the vehicle's previous power-on cycle, according to the vehicle's current driving conditions.

[0013] A third aspect of the present invention provides an electronic device, characterized in that it comprises:

[0014] One or more processors;

[0015] Storage device, on which one or more programs are stored,

[0016] When the one or more programs are executed by the one or more processors, the one or more processors implement the steps of the fuel cell power request determination method based on vehicle operating speed as described above.

[0017] A fourth aspect of the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, performs the steps of a method for determining a fuel cell power request based on vehicle operating speed.

[0018] The above one or more technical solutions have the following beneficial effects:

[0019] In this invention, by determining the current operating mode of the vehicle, when the vehicle is in hydrogen-electric operating mode and the SOC of the power battery is within a set threshold range, the current driving conditions of the vehicle, combined with the average power demand of the fuel cell vehicle corresponding to the operating speed range of the previous cycle, are applied to determine the fuel cell power request of the vehicle in the current cycle. The method of this invention determines the power request value based on the operating conditions, and has high adaptability to the operating conditions; moreover, it can maximize the direct utilization of the electricity generated by the fuel cell by the whole vehicle, avoid energy conversion loss, and improve the economy of the whole vehicle.

[0020] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0021] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0022] Figure 1 This is an overall flowchart of the fuel cell power request determination method based on vehicle operating speed in Embodiment 1 of the present invention. Detailed Implementation

[0023] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, 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 invention pertains.

[0024] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations of the present invention.

[0025] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0026] Example 1

[0027] This embodiment discloses a method for determining fuel cell power request based on vehicle operating speed, including:

[0028] Determine whether the vehicle is currently in hydrogen-electric mode;

[0029] If the vehicle is currently in hydrogen-electric mode and the SOC of the power battery is within the set threshold range, then the current driving condition of the vehicle is determined.

[0030] Based on the vehicle's operating conditions, the current requested power of the fuel cell is determined by the effective value of the average power demand of the fuel cell in the speed range corresponding to the vehicle's previous power-on cycle.

[0031] This embodiment determines the current operating mode of the vehicle. When the vehicle is in hydrogen-electric operating mode and the power battery SOC is within a set threshold range, it applies the current driving conditions of the vehicle, along with the average power demand of the fuel cell vehicle corresponding to the operating speed range of the previous cycle, to determine the fuel cell power request for the current cycle. This invention's method determines the power request value based on the operating conditions, exhibiting high adaptability. Furthermore, it maximizes the direct utilization of the electricity generated by the fuel cell by the entire vehicle, avoiding energy conversion losses and improving the overall vehicle economy.

[0032] This embodiment identifies the operating speed of the fuel cell vehicle and times the speed range it is in, calculates the average power demand of the fuel cell vehicle in different speed ranges during a single power cycle, and uses the average power demand as a reference value for the power request of the fuel cell system in the next power cycle.

[0033] The following is combined Figure 1 The fuel cell power request determination method based on vehicle operating speed in this embodiment will be described in detail below:

[0034] (1) Calculate the average power demand of fuel cell vehicles for the whole vehicle;

[0035] Let the first speed range, i.e. the low speed range, be 0-v1, the second speed range, i.e. the medium speed range, be v1-v2, and the third speed range, i.e. the high speed range, be v2-vmax, where vmax is the maximum vehicle speed.

[0036] Let t0 be the time threshold for calculating the average power demand of fuel cell vehicles in different speed ranges. Let t1 be the timing variable for the low-speed range, t2 for the medium-speed range, and t3 for the high-speed range.

[0037] Let the initial power-on cycle be T1, the second power-on cycle be T2, ..., and the nth power-on cycle be Tn.

[0038] Let P1L be the average power demand of fuel cell vehicles in the low-speed range during the initial power-on cycle T1, P1M be the average power demand of fuel cell vehicles in the medium-speed range during the initial power-on cycle T1, and P1H be the average power demand of fuel cell vehicles in the high-speed range during the initial power-on cycle T1; let P2L be the average power demand of fuel cell vehicles in the low-speed range during the second power-on cycle T2, P2M be the average power demand of fuel cell vehicles in the medium-speed range during the second power-on cycle T2, P2H be the average power demand of fuel cell vehicles in the high-speed range during the second power-on cycle T2, ..., let PnL be the average power demand of fuel cell vehicles in the low-speed range during the nth power-on cycle Tn, PnM be the average power demand of fuel cell vehicles in the medium-speed range during the nth power-on cycle Tn, and PnH be the average power demand of fuel cell vehicles in the high-speed range during the nth power-on cycle Tn.

[0039] For any period, the average power demand of a fuel cell vehicle at any speed range is calculated as follows: The average power demand of a fuel cell vehicle is the sum of the average output power of the power battery and the average output power of the boost DC-DC converter.

[0040] When the initial power-on signal of the vehicle is detected, the system is in cycle T1. When the vehicle speed is detected to be between 0 and v1, the time variable t1 starts timing. When the power-off signal is detected and t1 is greater than or equal to t0, P1L within T1 is calculated and saved, and t1 is cleared. When the vehicle speed is detected to be between v1 and v2, the time variable t2 starts timing. When the power-off signal is detected and t2 is greater than or equal to t0, P1M within T1 is calculated and saved, and t2 is cleared. When the vehicle speed is detected to be between v2 and vmax, the time variable t3 starts timing. When the power-off signal is detected and t3 is greater than or equal to t0, P1H within T1 is calculated and saved, and t3 is cleared. If t1 is less than t0, t2 is less than t0, and t3 is less than t0 during the power-on cycle, then P1L, P1M, and P1H in the corresponding speed range are invalid. If P1L is less than the average power demand threshold Py for fuel cell vehicles, then P1L is invalid. The reason for this restriction on P1L is to avoid false values ​​calculated when the vehicle is parked for a long time.

[0041] Similarly, when a power-on signal is detected for the vehicle, the system is in cycle T2. When the vehicle speed is detected to be between 0 and v1, the time variable t1 starts timing. When a power-off signal is detected and t1 is greater than or equal to t0, P2L within T2 is calculated and saved, overriding P1L, and t1 is cleared. When the vehicle speed is detected to be between v1 and v2, the time variable t2 starts timing. When a power-off signal is detected and t2 is greater than or equal to t0, P2M within T2 is calculated and saved, overriding P1M, and t2 is cleared. When the vehicle speed is detected to be between v2 and vmax, the time variable t3 starts timing. When a power-off signal is detected and t3 is greater than or equal to t0, P2H within T2 is calculated and saved, overriding P1H, and t3 is cleared. If t1 is less than t0, t2 is less than t0, and t3 is less than t0 during the power-on cycle, then P2L, P2M, and P2H in the corresponding speed range are invalid. If P2L is less than the average power demand threshold Py for fuel cell vehicles, then P2L is invalid. The reason for this restriction on P2L is to avoid false values ​​calculated when the vehicle is parked for a long time.

[0042] Similarly, the same calculation method applies to any power-on cycle.

[0043] It should be noted that the average power demand in the low-speed, medium-speed, and high-speed ranges during the power-on cycle is stored separately.

[0044] (2) Vehicle operating condition assessment;

[0045] The vehicle identifies characteristic parameters such as speed, acceleration, distance traveled, stopping time, and number of stops. By analyzing these characteristic parameters, the actual driving conditions of the vehicle are identified, categorized into bus driving conditions, highway driving conditions, and expressway driving conditions.

[0046] Since operating condition recognition requires a certain amount of time to accumulate, the initial operating condition is defined as the bus operating condition and saved. Once a change in operating condition is detected, the detected operating condition will be saved and overwrite the previously saved operating condition.

[0047] (3) The vehicle requests power from the fuel cell system;

[0048] When the SOC of the power battery is within the threshold range set by the vehicle and the vehicle is in hydrogen-electric operation mode: when the vehicle determines that the current operating condition is a bus operating condition, if no effective value of the average power demand of the fuel cell vehicle in the low-speed range is detected, the power requested by the vehicle from the fuel cell system is the first set power value PsL set by the vehicle; if an effective value of the average power demand of the fuel cell vehicle in the low-speed range is detected, the power requested by the vehicle from the fuel cell system is the effective value of the average power demand in the low-speed range.

[0049] It should be noted that after determining the bus operating condition, the system checks whether the effective value of the average demand power saved by the vehicle in the previous power cycle is the effective value of the average demand power of fuel cell vehicles in the low-speed range. If it is not detected, the requested power of the fuel cell system is the first set power value PsL set by the vehicle. If it is detected, the effective value of the saved average demand power of fuel cell vehicles in the low-speed range is used as the requested power of the current fuel cell system.

[0050] When the SOC of the power battery is within the threshold range set by the vehicle and the vehicle is in hydrogen-electric mode: When the vehicle determines that the current operating condition is a highway operating condition, if the effective value of the average power demand of the fuel cell vehicle in the low-speed and medium-speed ranges of the previous power cycle is not detected, the power requested by the vehicle from the fuel cell system is the second set power value PsM set by the vehicle; if the effective value in the low-speed range is detected but the effective value in the medium-speed range is not detected, the power requested by the vehicle from the fuel cell system is calculated as: 0.5 × the effective value of the average power demand of the fuel cell vehicle in the low-speed range. +0.5×PsM; If no effective value is detected in the low-speed range but an effective value is detected in the medium-speed range, the power requested by the vehicle from the fuel cell system is calculated as: 0.5×PsL + 0.5×effective value of the average power demand of the fuel cell vehicle in the medium-speed range; If effective values ​​of the average power demand of the fuel cell vehicle in both the low-speed and medium-speed ranges are detected, the power requested by the vehicle from the fuel cell system is calculated as: 0.5×effective value of the average power demand of the fuel cell vehicle in the low-speed range + 0.5×effective value of the average power demand of the fuel cell vehicle in the medium-speed range.

[0051] When the SOC of the power battery is within the threshold range set by the vehicle and the vehicle is in hydrogen-electric mode: when the vehicle determines that the current operating condition is a high-speed operating condition, if the effective value of the average power demand of the fuel cell vehicle in the high-speed range was not detected in the previous power cycle, the power requested by the vehicle from the fuel cell system is the third set power set value PsH set by the vehicle; if the effective value of the average power demand of the fuel cell vehicle in the high-speed range was detected, the power requested by the vehicle from the fuel cell system is the effective value of the average power demand in the high-speed range.

[0052] Wherein, the first set power value PsL < the second set power value PsM < the third set power value PsH.

[0053] When the SOC of the power battery is less than the lower limit of the SOC threshold range and the vehicle is in hydrogen-electric mode, the power requested by the vehicle from the fuel cell system is the rated power of the fuel cell.

[0054] When the SOC of the power battery is greater than the upper limit of the SOC threshold range and the vehicle is in hydrogen-electric mode, the power requested by the vehicle from the fuel cell system is the power corresponding to the maximum efficiency point of the fuel cell.

[0055] Example 2

[0056] The purpose of this embodiment is to provide a fuel cell power request determination system based on vehicle operating speed, including:

[0057] The first judgment module is configured to: determine whether the current vehicle is in hydrogen-electric working mode;

[0058] The second judgment module is configured to: if the current vehicle is in hydrogen-electric working mode and the power battery SOC is within a set threshold range, then determine the current driving condition of the vehicle.

[0059] The determination module is configured to: determine the current requested power of the fuel cell based on the effective value of the average power demand of the fuel cell in the speed range corresponding to the vehicle's previous power-on cycle, according to the vehicle's current driving conditions.

[0060] Example 3

[0061] The purpose of this embodiment is to provide an electronic device, characterized in that it includes:

[0062] One or more processors;

[0063] Storage device, on which one or more programs are stored,

[0064] When the one or more programs are executed by the one or more processors, the one or more processors implement the steps of the fuel cell power request determination method based on vehicle operating speed as described above.

[0065] Example 4

[0066] The purpose of this embodiment is to provide a computer-readable storage medium.

[0067] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, performs the steps of the above-described method for determining fuel cell power requests based on vehicle operating speed.

[0068] The steps and methods involved in the apparatuses of Embodiments 2, 3, and 4 above correspond to those in Embodiment 1. For specific implementation details, please refer to the relevant description section of Embodiment 1. The term "computer-readable storage medium" should be understood as a single medium or multiple media including one or more instruction sets; it should also be understood as including any medium capable of storing, encoding, or carrying an instruction set for execution by a processor and enabling the processor to perform any of the methods in this invention.

[0069] Those skilled in the art will understand that the modules or steps of the present invention described above can be implemented using general-purpose computer devices. Optionally, they can be implemented using computer-executable program code, thereby allowing them to be stored in a storage device for execution by a computer device, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. The present invention is not limited to any particular combination of hardware and software.

[0070] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A method of determining a fuel cell power request based on a vehicle operating speed, characterized by, include: Determine whether the vehicle is currently in hydrogen-electric mode; If the vehicle is currently in hydrogen-electric mode and the SOC of the power battery is within the set threshold range, then the current driving condition of the vehicle is determined. Based on the vehicle's operating conditions, the current requested power of the fuel cell is determined by the effective value of the average power demand of the fuel cell in the speed range corresponding to the vehicle's previous power cycle. Specifically: if the vehicle is currently in bus operation mode, determine whether the vehicle's previous power-on cycle met the effective value calculation of the average power demand of the fuel cell in the first speed range. If satisfied, the requested power of the vehicle's fuel cell is the effective value of the average power demand of the fuel cell in the first speed range. If not satisfied, the requested power of the vehicle's fuel cell is the first set power value; If the vehicle is currently in highway driving condition, determine whether the previous power-on cycle of the vehicle meets the effective value calculation of the average power demand of the fuel cell in the first speed range, or the effective value calculation of the average power demand of the fuel cell in the second speed range. If the previous power-on cycle met the effective value of the average power demand of the fuel cell in the first speed range, then the requested power of the vehicle's fuel cell is determined by the effective value of the average power demand of the fuel cell in the first speed range and the second set power value. If the previous power-on cycle met the effective value of the average power demand of the fuel cell in the second speed range, then the requested power of the vehicle's fuel cell is determined by the effective value of the average power demand of the fuel cell in the second speed range and the first set power value. If none of these conditions are met, the requested power of the vehicle's fuel cell will be the second set power value. The speed in the first speed range is less than the speed in the second speed range.

2. A method of determining a fuel cell power request based on vehicle operating speed as recited in claim 1, wherein, Based on the vehicle's current driving conditions, the current requested power of the fuel cell is determined by the average power demand of the fuel cell within the speed range corresponding to the vehicle's current driving conditions, including: If the vehicle is currently in a high-speed driving condition, determine whether the vehicle's previous power-on cycle met the effective value calculation of the average power demand of the fuel cell in the third speed range. If satisfied, the requested power of the vehicle's fuel cell is the effective value of the average power demand of the fuel cell in the third speed range. If not satisfied, the requested power of the vehicle's fuel cell will be the third set power value.

3. A method of determining a fuel cell power request based on vehicle operating speed according to any one of claims 1-2, wherein, The effective value of the average power demand of the fuel cell in the first, second, or third speed range is calculated under the following conditions: in the previous power-on cycle, the vehicle operating speed meets the first, second, or third speed range, and the corresponding power-on time is not less than the set time threshold.

4. A method for determining fuel cell power request based on vehicle operating speed as described in any one of claims 1-2, characterized in that, The effective value of the average power demand of the fuel cell in the first, second, or third speed range is calculated as the sum of the average output power of the power battery and the average output power of the boost DC-DC converter.

5. A fuel cell power request determination system based on vehicle operating speed, characterized in that, include: The first judgment module is configured to: determine whether the current vehicle is in hydrogen-electric working mode; The second judgment module is configured to: if the current vehicle is in hydrogen-electric working mode and the power battery SOC is within a set threshold range, then determine the current driving condition of the vehicle. The determination module is configured to: determine the current requested power of the fuel cell based on the effective value of the average demand power of the fuel cell in the speed range corresponding to the previous power cycle of the vehicle, according to the current driving condition of the vehicle; specifically: if the current vehicle is in bus driving condition, determine whether the current vehicle meets the effective value of the average demand power of the fuel cell in the first speed range in the previous power cycle. If satisfied, the requested power of the vehicle's fuel cell is the effective value of the average power demand of the fuel cell in the first speed range. If not satisfied, the requested power of the vehicle's fuel cell is the first set power value; If the vehicle is currently in highway driving condition, determine whether the previous power-on cycle of the vehicle meets the effective value calculation of the average power demand of the fuel cell in the first speed range, or the effective value calculation of the average power demand of the fuel cell in the second speed range. If the previous power-on cycle met the effective value of the average power demand of the fuel cell in the first speed range, then the requested power of the vehicle's fuel cell is determined by the effective value of the average power demand of the fuel cell in the first speed range and the second set power value. If the previous power-on cycle met the effective value of the average power demand of the fuel cell in the second speed range, then the requested power of the vehicle's fuel cell is determined by the effective value of the average power demand of the fuel cell in the second speed range and the first set power value. If none of these conditions are met, the requested power of the vehicle's fuel cell will be the second set power value. The speed in the first speed range is less than the speed in the second speed range.

6. An electronic device, characterized in that, include: One or more processors; Storage device, on which one or more programs are stored, When the one or more programs are executed by the one or more processors, the one or more processors implement the steps of a fuel cell power request determination method based on vehicle operating speed as described in any one of claims 1-4.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, performs the steps of a fuel cell power request determination method based on vehicle operating speed as described in any one of claims 1 to 4.

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