Vehicle energy management method for hydrogen fuel cell vehicle

Abstract

The invention discloses a whole vehicle energy management method for a hydrogen fuel cell vehicle. The method comprises the steps that the whole vehicle working condition is determined; according to the whole vehicle working condition, the average power interval section and the idle speed power are calibrated; judging whether the current average power interval section is the first average power interval section after the fuel cell is started or not; calculating the average vehicle demand power in the previous power interval section; and determining the output power of the fuel cell system in the current average power interval according to the comparison result of the average vehicle demand power and the idle speed power in the previous power interval. According to the whole vehicle energy management method of the hydrogen fuel cell vehicle, special working conditions can be recognized, proper fuel cell output is provided, and the dynamic property and economical efficiency are ensured; the power demand of the whole vehicle and the power request of the fuel cell system are accurately analyzed, the power demand of the whole vehicle is ensured to be met under the condition that the variable load rate is not high, and excessive electric quantity is prevented from being charged into the power cell to cause increase of hydrogen consumption and loss of charging and discharging in the process.

Description

Technical Field

[0001] The present invention relates to the technical field of energy management of new energy vehicles, and more specifically, to a whole vehicle energy management method for a hydrogen fuel cell vehicle. Background Art

[0002] Hydrogen fuel cell vehicles are regarded as electric vehicles with their own hydrogen fuel generators. Their driving force comes from the electric motors on the vehicle, which makes hydrogen fuel cell vehicles comparable to traditional vehicles in performance. At the same time, their environmental protection and high efficiency advantages such as zero emissions, fast energy replenishment, and renewable fuels are increasingly valued by vehicle manufacturers. At present, the development of hydrogen fuel cell vehicles has been vigorously promoted by governments, enterprises, universities and scientific research institutions. Although their current market share is relatively low, with the advancement of technology and the improvement of infrastructure, it is expected that hydrogen fuel cell vehicles will be more widely used and promoted worldwide in the future. As a rechargeable hybrid vehicle equipped with fuel cells, the management and distribution of the energy flow of the vehicle is crucial. It is necessary to take into account the power while doing a good job of the economy of hydrogen fuel. At the same time, combined with the inherent characteristics of hydrogen fuel cells (frequent load changes will accelerate the attenuation of fuel cells and affect their lifespan), the service life of hydrogen fuel cells should be extended as much as possible, so as to better promote the installation of hydrogen fuel cell technology in vehicles, increase market share, and further promote the development of the fuel cell industry.

[0003] The current energy management strategies for hydrogen fuel vehicles are mainly divided into thermostat strategies, power following strategies, and composite strategies that combine various strategies. The thermostat strategy is implemented by allowing the fuel cell system to work at a fixed power in a fixed SOC interval of the vehicle (for example: if the SOC of the vehicle is in the range of 50%-60%, the output power of the fuel cell system is 35KW, and if the SOC of the vehicle is in the range of 60%-70%, the output power of the fuel cell system is 32KW). Although the thermostat strategy is simple to control and easy to implement, and has a low load change rate, it can reduce the attenuation rate of the fuel cell system. The first disadvantage is that it has no recognition of the vehicle's operating conditions and cannot adjust the power for complex conditions. For example, when climbing a slope, the power cannot be increased, which easily causes insufficient power for the vehicle and cannot go uphill. The second disadvantage is that when the power request is not high, the fuel cell system continues to output high power, and the advantages of plug-in charging of the vehicle cannot be used, resulting in poor economy of the vehicle. The third disadvantage is that the energy generated by hydrogen is used to charge the battery, and then the battery is discharged for use, which greatly reduces the utilization rate of hydrogen and increases the hydrogen consumption of the vehicle. The power following strategy is implemented by the vehicle VCU providing the real-time power demand of the vehicle, so that the fuel cell works according to the VCU power demand (e.g. if the current vehicle power demand is 35KW, the fuel cell system provides 35KW, and if the demand is 32KW at the next moment, the fuel cell system provides 32KW). Although the power following strategy is also simple to control and easy to implement, with good power performance, it will not be unable to climb hills, and the energy generated by hydrogen is directly used, which improves the utilization rate of hydrogen, but the disadvantage is that frequent load changes will greatly reduce the service life of the fuel cell and increase the full life cost of the fuel cell vehicle.

[0004] Therefore, there is an urgent need for a whole vehicle energy management method for hydrogen fuel cell vehicles. Summary of the invention

[0005] The purpose of the present invention is to provide a whole vehicle energy management method for a hydrogen fuel cell vehicle to solve the above-mentioned problems in the prior art, and to be able to identify special operating conditions (uphill and downhill and horizontal roads, etc.), provide appropriate fuel cell output, and ensure power and economy.

[0006] The present invention provides a whole vehicle energy management method for a hydrogen fuel cell vehicle, which comprises:

[0007] Step S1, determining the vehicle operating condition, wherein the vehicle operating condition includes a horizontal driving condition, a climbing driving condition or a downhill driving condition. If the vehicle operating condition is a horizontal driving condition or a climbing driving condition, then executing steps S2 to S6; if the vehicle operating condition is a downhill driving condition, then executing step S7;

[0008] Step S2: calibrate the average power interval and idle power according to the vehicle working condition;

[0009] Step S3, determining whether the current average power interval is the first average power interval after the fuel cell is started, if not, executing steps S4 and S5, if yes, executing step S6;

[0010] Step S4, calculating the average vehicle power demand in the previous average power interval;

[0011] Step S5, determining the output power of the fuel cell system in the current average power interval according to the comparison result between the average vehicle demand power and the idle power in the previous average power interval;

[0012] Step S6, the output power of the fuel cell system is the idle power;

[0013] Step S7: determining the output power of the fuel cell system according to the vehicle power request.

[0014] In the above-mentioned vehicle energy management method for hydrogen fuel cell vehicles, preferably, the step S1, determining the vehicle operating condition, specifically includes:

[0015] Step S11, using a gyroscope to collect vehicle posture data;

[0016] Step S12: The vehicle FCU or the vehicle VCU collects data collected by the gyroscope to determine the vehicle posture, wherein the vehicle posture includes a horizontal state, an elevation state, or a depression state;

[0017] Step S13, determining the vehicle operating condition according to the vehicle posture, wherein the vehicle operating condition corresponding to the horizontal state is the horizontal driving condition, the vehicle operating condition corresponding to the elevation state is the climbing driving condition, and the vehicle operating condition corresponding to the depression state is the downhill driving condition.

[0018] In the above-mentioned vehicle energy management method for hydrogen fuel cell vehicles, preferably, the step S2, calibrating the average power interval and the idle power according to the vehicle operating conditions, specifically includes:

[0019] Step S21: When the vehicle is in a horizontal driving condition, calibrate the average power interval according to the vehicle condition. and idle power ;

[0020] Step S22: When the vehicle is in a climbing condition, calibrate the average power interval according to the vehicle elevation angle. and idle power , and the average power interval As the slope increases, the idle power decreases. Increases with increasing slope.

[0021] In the above-mentioned vehicle energy management method for hydrogen fuel cell vehicles, preferably, the step S4, calculating the average vehicle power demand in the previous average power interval, specifically includes:

[0022] In the last average power interval In the time period from the beginning to the end of the vehicle, the vehicle demand power is integrated to obtain the previous average power interval The integral required power within ;

[0023] In the average power range After the end, calculate the previous average power interval Average vehicle power requirement within is the integral required power in the corresponding time period .

[0024] The whole vehicle energy management method of the hydrogen fuel cell vehicle as described above, wherein preferably, the step S5, determining the output power of the fuel cell system in the current average power interval according to the comparison result of the average whole vehicle demand power and the idle power in the previous average power interval, specifically includes:

[0025] If the previous average power interval Average vehicle power requirement within Greater than the idle power of the corresponding working conditions , then the output power of the fuel cell system in the current average power interval is for ;

[0026] If the previous average power interval Average vehicle power requirement within Less than the idle power of the corresponding working condition , then the output power of the fuel cell system in the current average power interval is Idle power .

[0027] In the above-mentioned vehicle energy management method for hydrogen fuel cell vehicles, preferably, the step S7, determining the output power of the fuel cell system according to the vehicle power request, specifically includes:

[0028] If there is no vehicle power request, the fuel cell system will shut down.

[0029] The present invention provides a whole vehicle energy management method for a hydrogen fuel cell vehicle, which can accurately analyze the whole vehicle power demand and the fuel cell system power request, ensure that the whole vehicle power demand is met when the fuel cell system load change rate is not high, avoid charging excess electricity into the power battery, cause the increase of hydrogen consumption and the loss of charging and discharging in the process; reduce the load rate of the fuel cell system under normal working conditions, reduce the attenuation rate of the fuel cell, increase the service life of the fuel cell, and reduce the cost of the whole use cycle; identify the attitude angle of the whole vehicle through a gyroscope, facilitate the adjustment of the strategy according to the attitude angle, determine the power demand of the whole vehicle, adjust the power output state of the fuel cell system, achieve special working conditions, and avoid hydrogen from charging the power battery excessively in the comprehensive working condition of the vehicle, reduce hydrogen consumption, and reduce the cost of hydrogen use; under the working condition where the vehicle has high requirements for power output and rapid response, the idle power and the average power time period can be autonomously adjusted according to the power output and response speed of the whole vehicle, increase the power output of the whole vehicle by increasing the idle speed, and reduce the time of the average power time period to increase the response speed, avoid the occurrence of insufficient power, and ensure the power of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described below with reference to the accompanying drawings, in which:

[0031] Figure 1 A flow chart of an embodiment of a whole vehicle energy management method for a hydrogen fuel cell vehicle provided by the present invention;

[0032] Figure 2 This is a logic diagram of an embodiment of the whole vehicle energy management method for a hydrogen fuel cell vehicle provided by the present invention. DETAILED DESCRIPTION

[0033] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The description of the exemplary embodiments is merely illustrative and is in no way intended to limit the present disclosure and its application or use. The present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to make the present disclosure thorough and complete and to fully express the scope of the present disclosure to those skilled in the art. It should be noted that unless otherwise specifically stated, the relative arrangement of the components and steps, the composition of the materials, the numerical expressions and the numerical values ​​set forth in these embodiments should be interpreted as being merely exemplary and not as limiting.

[0034] The words "first", "second" and similar words used in this disclosure do not indicate any order, quantity or importance, but are only used to distinguish different parts. The words "include" or "comprises" and similar words mean that the elements before the word include the elements listed after the word, and do not exclude the possibility of including other elements. "Up", "down" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0035] In the present disclosure, when a specific component is described as being located between a first component and a second component, there may or may not be an intermediate component between the specific component and the first component or the second component. When a specific component is described as being connected to other components, the specific component may be directly connected to the other components without an intermediate component, or may not be directly connected to the other components but have an intermediate component.

[0036] All terms (including technical terms or scientific terms) used in the present disclosure have the same meanings as those understood by ordinary technicians in the field to which the present disclosure belongs, unless otherwise specifically marked. It should also be understood that terms marked in general dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant technology, and should not be interpreted in an idealized or extremely formal sense, unless explicitly marked as such here.

[0037] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered part of the specification.

[0038] like Figure 1 and Figure 2 As shown, the whole vehicle energy management method for hydrogen fuel cell vehicles provided in this embodiment includes the following steps in actual implementation:

[0039] Step S1, determine the vehicle operating condition, the vehicle operating condition includes a horizontal driving condition, a climbing driving condition or a downhill driving condition. If the vehicle operating condition is a horizontal driving condition or a climbing driving condition, execute steps S2 to S6; if the vehicle operating condition is a downhill driving condition, execute step S7.

[0040] In one embodiment of the whole vehicle energy management method of a hydrogen fuel cell vehicle of the present invention, the step S1 may specifically include:

[0041] Step S11: Collect vehicle posture data using a gyroscope.

[0042] Step S12: The vehicle FCU (Fuel cell Control Unit) or the vehicle VCU (Vehicle Control Unit) collects data collected by the gyroscope to determine the vehicle posture.

[0043] The vehicle posture includes a horizontal state, an elevation state or a depression state.

[0044] Step S13: determining the vehicle operating condition according to the vehicle posture.

[0045] Among them, the whole vehicle working condition corresponding to the horizontal state is the horizontal driving condition, the whole vehicle working condition corresponding to the elevation angle state is the climbing driving condition, and the whole vehicle working condition corresponding to the depression angle state is the downhill driving condition.

[0046] By adding a gyroscope to the system, the attitude angle of the entire vehicle can be identified, making it easier to adjust the strategy based on the attitude angle and adjust the power output state of the fuel cell system to achieve special working conditions.

[0047] Step S2: calibrate the average power range and idle power according to the vehicle operating conditions.

[0048] In one embodiment of the whole vehicle energy management method of a hydrogen fuel cell vehicle of the present invention, the step S2 may specifically include:

[0049] Step S21: When the vehicle is in a horizontal driving condition, calibrate the average power interval according to the vehicle condition. and idle power .

[0050] In one embodiment of the present invention, an average power interval is defined. For 5min and an idle power It should be noted that the average power range under horizontal driving conditions is and idle power All need to be calibrated according to the vehicle conditions, and the data here are only for example.

[0051] Step S22: When the vehicle is in a climbing condition, calibrate the average power interval according to the vehicle elevation angle. and idle power , and the average power interval As the slope increases, the idle power decreases. Increases with increasing slope.

[0052] In one embodiment of the present invention, an average power interval is defined. For 1min and an idle power The average power interval is 15KW. According to the definition of vehicle elevation angle, the shorter the average power interval time, the shorter the average power interval time. Decreases as the slope increases; idle power According to the definition of vehicle elevation angle, the greater the elevation angle, the greater the idle power. It should be noted that the average power range under climbing conditions is and idle power All need to be calibrated according to the vehicle conditions, and the data here are only for example.

[0053] Under climbing conditions, by increasing the idle power and reducing the average power time period, the fuel cell system load change rate is accelerated, the system's power output and response are increased, and sufficient power is provided for the vehicle to climb.

[0054] Step S3, determine whether the current average power interval is the first average power interval after the fuel cell is started, if not, execute steps S4 and S5, if yes, execute step S6.

[0055] Step S4: Calculate the average vehicle power requirement in the previous average power interval.

[0056] In one embodiment of the whole vehicle energy management method of a hydrogen fuel cell vehicle of the present invention, the step S4 may specifically include:

[0057] Step S41: In the last average power interval In the time period from the beginning to the end of the vehicle, the vehicle demand power is integrated to obtain the previous average power interval The integral required power within .

[0058] Step S42: In the average power interval After the end, calculate the previous average power interval Average vehicle power requirement within is the integral required power in the corresponding time period .

[0059] The fuel cell starts up and passes the first average power interval After that, the power request of the previous time period is input into the controller, and the fuel cell system is based on the previous average power interval. The average power output within.

[0060] Step S5: Determine the output power of the fuel cell system in the current average power interval according to the comparison result between the average vehicle demand power and the idle power in the previous average power interval.

[0061] Specifically, if the previous average power interval Average vehicle power requirement within Greater than the idle power of the corresponding working conditions , then the output power of the fuel cell system in the current average power interval is for ;

[0062] If the previous average power interval Average vehicle power requirement within Less than the idle power of the corresponding working condition , then the output power of the fuel cell system in the current average power interval is Idle power .

[0063] During the operation of the fuel cell system, if the average power interval If the average vehicle power demand within the range is less than the idle power, the fuel cell system outputs according to the idle power.

[0064] Step S6: The output power of the fuel cell system is the idle power.

[0065] When the fuel cell system is started, the first average power interval In this case, the power request is not input into the controller and is judged as 0. At this time, the fuel cell system outputs according to the idle power.

[0066] Under horizontal driving conditions, the loading rate of the fuel cell system can be greatly reduced, and the service life of the fuel cell can be increased. This strategy can accurately calculate the power demand of the entire vehicle by calculating the power demand of the entire vehicle in the previous time period, and then provide power as required through the fuel cell system, thereby reducing hydrogen consumption while providing power requirements. The SOC consumed in the early stage of the battery can be replenished through the charging pile to avoid energy waste caused by hydrogen charging.

[0067] Under climbing conditions, by increasing the idle power and reducing the average power time period, the fuel cell system's load change rate is accelerated, the system's power output and response are increased, and sufficient power is provided for the vehicle to climb. The SOC consumed in the early stage of the battery can be replenished through the charging pile, avoiding energy waste caused by hydrogen charging.

[0068] Step S7: determining the output power of the fuel cell system according to the vehicle power request.

[0069] Specifically, if there is no vehicle power request, the fuel cell system will be shut down, which can reduce the power consumption of the BOP (auxiliary) system and reduce the energy consumption of the vehicle.

[0070] The whole vehicle energy management method of a hydrogen fuel cell vehicle provided by an embodiment of the present invention can accurately analyze the whole vehicle power demand and the fuel cell system power request, ensure that the whole vehicle power demand is met when the fuel cell system load change rate is not high, avoid charging excess electricity into the power battery, resulting in increased hydrogen consumption and loss during charging and discharging; reduce the load rate of the fuel cell system under normal working conditions, reduce the attenuation rate of the fuel cell, increase the service life of the fuel cell, and reduce the cost of the entire use cycle; identify the attitude angle of the whole vehicle through a gyroscope, facilitate the adjustment of the strategy according to the attitude angle, determine the power demand of the whole vehicle, adjust the power output state of the fuel cell system, achieve special working conditions, and avoid hydrogen from charging the power battery excessively in the comprehensive working condition of the vehicle, reduce hydrogen consumption, and reduce the cost of hydrogen use; under working conditions where the vehicle has high requirements for power output and rapid response, it can autonomously adjust the idle power and average power time period according to the whole vehicle power output and response speed, increase the whole vehicle power output by increasing the idle speed, and reduce the time of the average power time period to increase the response speed, avoid the occurrence of insufficient power, and ensure the power of the vehicle.

[0071] So far, various embodiments of the present disclosure have been described in detail. In order to avoid obscuring the concept of the present disclosure, some details known in the art are not described. Based on the above description, those skilled in the art can fully understand how to implement the technical solution disclosed here.

[0072] Although some specific embodiments of the present disclosure have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present disclosure. It should be understood by those skilled in the art that the above embodiments may be modified or some technical features may be replaced by equivalents without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.

Claims

1. A whole vehicle energy management method for a hydrogen fuel cell vehicle, characterized in that: include: Step S1, determining the vehicle operating condition, wherein the vehicle operating condition includes a horizontal driving condition, a climbing driving condition or a downhill driving condition. If the vehicle operating condition is a horizontal driving condition or a climbing driving condition, then executing steps S2 to S6; if the vehicle operating condition is a downhill driving condition, then executing step S7; Step S2: calibrate the average power interval and idle power according to the vehicle working condition; Step S3, determining whether the current average power interval is the first average power interval after the fuel cell is started, if not, executing steps S4 and S5, if yes, executing step S6; Step S4, calculating the average vehicle power demand in the previous average power interval; Step S5, determining the output power of the fuel cell system in the current average power interval according to the comparison result between the average vehicle demand power and the idle power in the previous average power interval; Step S6, the output power of the fuel cell system is the idle power; Step S7: determining the output power of the fuel cell system according to the vehicle power request.

2. The whole vehicle energy management method of a hydrogen fuel cell vehicle according to claim 1, characterized in that: The step S1, determining the vehicle operating condition, specifically includes: Step S11, using a gyroscope to collect vehicle posture data; Step S12: The vehicle FCU or the vehicle VCU collects data collected by the gyroscope to determine the vehicle posture, wherein the vehicle posture includes a horizontal state, an elevation state, or a depression state; Step S13, determining the vehicle operating condition according to the vehicle posture, wherein the vehicle operating condition corresponding to the horizontal state is the horizontal driving condition, the vehicle operating condition corresponding to the elevation state is the climbing driving condition, and the vehicle operating condition corresponding to the depression state is the downhill driving condition.

3. The whole vehicle energy management method of a hydrogen fuel cell vehicle according to claim 1, characterized in that: The step S2, calibrating the average power interval and the idle power according to the vehicle working condition, specifically includes: Step S21: When the vehicle is in a horizontal driving condition, calibrate the average power interval according to the vehicle condition. and idle power ; Step S22: When the vehicle is in a climbing condition, calibrate the average power interval according to the vehicle elevation angle. and idle power , and the average power interval As the slope increases, the idle power decreases. Increases with increasing slope.

4. The whole vehicle energy management method of a hydrogen fuel cell vehicle according to claim 1, characterized in that: The step S4, calculating the average vehicle required power in the previous average power interval, specifically includes: In the last average power interval In the time period from the beginning to the end of the vehicle, the vehicle demand power is integrated to obtain the previous average power interval The integral required power within ; In the average power range After the end, calculate the previous average power interval Average vehicle power requirement within is the integral required power in the corresponding time period .

5. The whole vehicle energy management method of a hydrogen fuel cell vehicle according to claim 1, characterized in that: The step S5, determining the output power of the fuel cell system in the current average power interval according to the comparison result of the average vehicle demand power and the idle power in the previous average power interval, specifically includes: If the previous average power interval Average vehicle power requirement within Greater than the idle power of the corresponding working conditions , then the output power of the fuel cell system in the current average power range is for ; If the previous average power interval Average vehicle power requirement within Less than the idle power of the corresponding working condition , then the output power of the fuel cell system in the current average power range is Idle power .

6. The whole vehicle energy management method of a hydrogen fuel cell vehicle according to claim 1, characterized in that: The step S7, determining the output power of the fuel cell system according to the vehicle power request, specifically includes: If there is no vehicle power request, the fuel cell system will shut down.

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