Fuel cell automobile energy management method based on fixed time period

Abstract

The invention discloses a fuel cell automobile energy management method based on a fixed time period, which comprises the following steps: after the whole automobile is started, determining whether to start a fuel cell system according to the SOC (State of Charge) of a power battery and the current working condition; after the fuel cell system is started, the output power of the fuel cell system is determined according to the energy consumption of the fixed time period. According to the fuel cell automobile energy management method based on the fixed time period, a simple and efficient energy management strategy is provided, the energy management strategy based on the fixed time period is optimized by adding a fuel cell system start-stop strategy and an output power correction coefficient, and the energy management efficiency of the fuel cell automobile is improved by optimizing an output power calculation method of the fuel cell system. According to the method, the # imgabs0 # of the power battery is maintained at the value during starting, unnecessary charging is avoided, the economical efficiency of the system is improved, meanwhile, the variable load of the fuel battery is reduced, the service life of the fuel battery is prolonged, and more efficient energy management is achieved on the basis that the service life of the fuel battery is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of battery energy management, and more specifically, to a fuel cell vehicle energy management method based on a fixed period. Background Art

[0002] As a new type of clean energy vehicle, fuel cell vehicles have attracted more and more attention due to their high efficiency, environmental protection and long driving range. Fuel cell hybrid vehicles combine fuel cells and power battery systems, and through the coordinated work of the two, they optimize power output and maximize energy utilization efficiency. Therefore, the energy management system plays a vital role: under various driving conditions, reasonably allocate energy output between fuel cells and power batteries to ensure the efficiency and economy of vehicle operation; monitor the status of fuel cells and power batteries in real time, and make timely adjustments to extend the service life of the system; optimize energy utilization strategies to maximize the vehicle's driving range.

[0003] Although fuel cell vehicles have made some progress in energy management, the current energy management strategies still have some shortcomings: traditional energy management strategies are difficult to achieve optimal energy distribution between fuel cells and power batteries under various complex driving conditions; the current energy management system has a slow response speed when dealing with rapidly changing driving needs, affecting the driving experience; some energy management strategies rely on complex optimization algorithms, which have a large amount of calculations and are difficult to apply in real time in actual vehicles.

[0004] Therefore, there is an urgent need for a fuel cell vehicle energy management method based on fixed time periods. Summary of the invention

[0005] The purpose of the present invention is to provide a fuel cell vehicle energy management method based on a fixed period to solve the above-mentioned problems in the prior art and to maintain the stability of the power of the power battery without frequently changing the load power of the battery stack.

[0006] The present invention provides a fuel cell vehicle energy management method based on a fixed period, which includes:

[0007] After the vehicle is started, it determines whether to start the fuel cell system based on the power battery SOC and current operating conditions;

[0008] After the fuel cell system is started, the output power of the fuel cell system is determined based on the energy consumption in a fixed time period.

[0009] As described above, the fuel cell vehicle energy management method based on a fixed period, wherein preferably, after the vehicle is started, determining whether to start the fuel cell system according to the power battery SOC and the current operating conditions specifically includes:

[0010] According to the road condition mode, the opening state of the fuel cell system manual switch and the threshold value corresponding to the current SOC and different road condition modes Determine whether to start the fuel cell system.

[0011] In the above-mentioned fuel cell vehicle energy management method based on fixed time periods, preferably, the thresholds corresponding to the different road condition modes are include: and ,in, represents the upper limit value under the i-th road condition mode, represents the intermediate threshold value under the i-th road condition mode, Indicates the lower limit value under the i-th road condition mode.

[0012] As described above, the fuel cell vehicle energy management method based on a fixed period, wherein preferably, after the vehicle is started, determining whether to start the fuel cell system according to the power battery SOC and the current operating conditions specifically includes:

[0013] Step S11, start: first determine whether the high voltage of the vehicle is turned on, if it is turned on, go to step S12; otherwise, loop detection;

[0014] Step S12, selecting a road condition mode: selecting different road condition modes according to different road conditions;

[0015] Step S13, determining the state of the manual switch of the fuel cell system: if the manual switch is on, proceed to step S14, otherwise proceed to step S15;

[0016] Step S14: Put the power battery Value and current traffic mode Upper limit For comparison: If the power battery The value is less than the current traffic mode Upper limit , the fuel cell system is started, and then the process returns to step S11; otherwise, the fuel cell system is not started, and the process returns to step S11;

[0017] Step S15: Put the power battery The SOC lower limit value corresponding to the current road condition mode For comparison: If the power battery The value is less than the SOC lower limit corresponding to the current road condition mode , the fuel cell system is started, and then the process goes to step S16; otherwise, the fuel cell system is not started, and then the process goes back to step S11;

[0018] Step S16: Put the power battery The middle threshold between the value and the current traffic mode For comparison: If the power battery The value is greater than the middle threshold corresponding to the current traffic mode , then turn off the fuel cell system and then return to step S11; otherwise, directly return to step S11.

[0019] As described above, the fuel cell vehicle energy management method based on a fixed period, wherein preferably, after the fuel cell system is started, the output power of the fuel cell system is determined according to the energy consumption in the fixed period, specifically including:

[0020] Calculate the average power consumption of the whole vehicle in the previous time period, and calculate the initial power demand based on the comparison result of the average power consumption of the whole vehicle in the previous time period with the idle power; optimize the initial power demand based on the fuel cell output power correction coefficient and the power difference correction coefficient to obtain the optimized power demand; determine the output power of the fuel cell system in the current time period based on the comparison result of the optimized power demand and the output power of the fuel cell system in the previous time period.

[0021] As described above, the fuel cell vehicle energy management method based on a fixed period, wherein preferably, after the fuel cell system is started, the output power of the fuel cell system is determined according to the energy consumption in the fixed period, specifically including:

[0022] Step S21, start: record the power battery initial value at the time of fuel cell system start-up. value , then proceed to step S22;

[0023] Step S22: Power calculation: Calculate the average power consumption of the vehicle in the previous time period , then proceed to step S23;

[0024] Step S23: according to the average power consumption of the vehicle in the previous time period and idling power The comparison results of the initial power requirement are calculated. :The average power consumption of the vehicle in the previous period and idling power The initial power requirement is compared with is the larger value of the two, and then goes to step S24;

[0025] Step S24, calculate the power difference: use the initial power Subtract the current power Get the current With initial The difference ,like , the optimized required power is calculated by the following formula : ,in, represents the correction factor, With initial power demand Negative correlation, With the current With initial The difference positive correlation, then enter step S25; otherwise, the fuel cell system output power in the current time period Initial power requirement , return to step S22;

[0026] Step S25, power comparison: according to the optimized required power Compared with the output power of the fuel cell system in the previous period The comparison result is used to determine the output power of the fuel cell system in the current time period: , then the output power of the fuel cell system in the current time period is , then returns to step S22; otherwise, the output power of the fuel cell system in the current time period is , then return to step S22.

[0027] The present invention provides a fuel cell vehicle energy management method based on a fixed period of time, provides a simple and efficient energy management strategy, optimizes the energy management strategy based on a fixed period of time by adding a fuel cell system start-stop strategy and an output power correction coefficient, and optimizes the output power calculation method of the fuel cell system to calculate the power of the power battery. Maintaining the value at startup avoids unnecessary charging, improves the economy of the system, and at the same time reduces the variable load on the fuel cell, prolongs the life of the fuel cell, and achieves more efficient energy management on the basis of ensuring the life of the fuel cell; on the basis of the energy management strategy based on a fixed time period, a road condition selection strategy is added to adapt to complex road conditions, which solves the shortcomings of traditional strategies that cannot adapt to complex and changeable road conditions, and optimizes the output power calculation method to maintain the stability of the power battery without frequently changing the stack load power; by setting the upper limit value for the power battery in the current road condition mode, overcharging of the power battery is avoided, which not only avoids energy waste but also prolongs the life of the power battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] 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:

[0029] Figure 1A flow chart of an embodiment of a fuel cell vehicle energy management method based on a fixed period provided by the present invention;

[0030] Figure 2 A logic diagram for starting a fuel cell system;

[0031] Figure 3 Logic diagram for determining the output power of a fuel cell system. DETAILED DESCRIPTION

[0032] 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.

[0033] 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.

[0034] 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.

[0035] 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 defined. It should also be understood that terms defined in general dictionaries, such as 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 defined herein.

[0036] 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.

[0037] In the current energy management strategy, the output power of the fuel cell each time is based on the average output power of the previous time period, which has obvious lag, which may cause the power battery to be overcharged or over-discharged, and the SOC of the power battery cannot be maintained at a stable level, which will affect the stability, efficiency and life of the system. In addition, in the face of complex road conditions (such as mountain roads, urban traffic, etc.), driving needs change frequently, and fixed time period strategies are difficult to adapt to these changes, resulting in poor energy management effects.

[0038] like Figure 1 As shown, the fuel cell vehicle energy management method based on a fixed period provided in this embodiment includes the following steps in actual execution:

[0039] Step S1: After the vehicle is started, determine whether to start the fuel cell system based on the power battery SOC and current operating conditions.

[0040] In one embodiment of the present invention, according to the road condition mode, the on state of the manual switch of the fuel cell system and the threshold values ​​corresponding to the current SOC and different road condition modes, Determine whether to start the fuel cell system.

[0041] Among them, the thresholds corresponding to the different road condition modes are include: and ,in, represents the upper limit value under the i-th road condition mode, represents the intermediate threshold value under the i-th road condition mode, Indicates the lower limit value under the i-th road condition mode.

[0042] Under different working conditions, different lower limit SOCs are set for the power battery to meet the power requirements of the entire vehicle. At the same time, by setting an upper limit value for the SOC of the power battery, overcharging can be avoided.

[0043] like Figure 2 As shown, in one embodiment of the fuel cell vehicle energy management method based on a fixed period of time of the present invention, the step S1 may specifically include:

[0044] Step S11, start: first determine whether the high voltage of the vehicle is turned on, if it is turned on, go to step S12; otherwise, loop detection.

[0045] Step S12, selecting a road condition mode: selecting different road condition modes according to different road conditions.

[0046] Step S13, determine the state of the manual switch of the fuel cell system: if the manual switch is turned on, proceed to step S14, otherwise proceed to step S15.

[0047] Step S14: Put the power battery Value and current traffic mode Upper limit For comparison: If the power battery The value is less than the current traffic mode Upper limit , the fuel cell system is started, and then the process returns to step S11; otherwise, the fuel cell system is not started, and the process returns to step S11.

[0048] Step S15: Put the power battery The SOC lower limit value corresponding to the current road condition mode For comparison: If the power battery The value is less than the SOC lower limit corresponding to the current road condition mode , the fuel cell system is started, and then the process goes to step S16; otherwise, the fuel cell system is not started, and then the process returns to step S11.

[0049] Step S16: Put the power battery The middle threshold between the value and the current traffic mode For comparison: If the power battery The value is greater than the middle threshold corresponding to the current traffic mode , then turn off the fuel cell system and then return to step S11; otherwise, directly return to step S11.

[0050] Step S2: After the fuel cell system is started, the output power of the fuel cell system is determined according to the energy consumption in a fixed time period.

[0051] In one embodiment of the present invention, the average power consumption of the whole vehicle in the previous time period is calculated, and based on the comparison result of the average power consumption of the whole vehicle in the previous time period with the idle power, the initial required power is calculated; the initial required power is optimized based on the fuel cell output power correction coefficient and the power difference correction coefficient to obtain the optimized required power; based on the comparison result of the optimized required power with the output power of the fuel cell system in the previous time period, the output power of the fuel cell system in the current time period is determined.

[0052] like Figure 3 As shown, in one embodiment of the fuel cell vehicle energy management method based on a fixed period of time of the present invention, the step S2 may specifically include:

[0053] Step S21, start: record the power battery initial value at the time of fuel cell system start-up. value , then proceed to step S22.

[0054] Step S22: Power calculation: Calculate the average power consumption of the vehicle in the previous time period , then go to step S23.

[0055] Step S23: according to the average power consumption of the vehicle in the previous time period and idling power The comparison results of the initial power requirement are calculated. :The average power consumption of the vehicle in the previous period and idling power The initial power requirement is compared with is the larger value between the two, and then enters step S24.

[0056] Step S24, calculate the power difference: use the initial power Subtract the current power Get the current With initial The difference ,like , the optimized required power is calculated by the following formula : ,in, represents the correction factor, With initial power demand Negative correlation, With the current With initial The difference positive correlation, then enter step S25; otherwise, the fuel cell system output power in the current time period Initial power requirement , return to step S22.

[0057] in, , by using the correction factor Optimizing the initial power demand can maintain the stability of the power battery SOC and introduce a correction factor .in, is the fuel cell output power correction coefficient, which is negatively correlated with the required output power of the fuel cell; is the power difference correction coefficient, which is positively correlated with the power difference of the fuel cell system.

[0058] When the power battery SOC is less than the starting value, that is, When the fuel cell maintains the power output of the previous time period , which can avoid frequent changes in the fuel cell load power.

[0059] Step S25, power comparison: according to the optimized required power Compared with the output power of the fuel cell system in the previous period The comparison result is used to determine the output power of the fuel cell system in the current time period: , then the output power of the fuel cell system in the current time period is , then returns to step S22; otherwise, the output power of the fuel cell system in the current time period is , then return to step S22.

[0060] The fuel cell vehicle energy management method based on fixed time periods provided in the embodiment of the present invention provides a simple and efficient energy management strategy, which optimizes the energy management strategy based on fixed time periods by adding a fuel cell system start-stop strategy and an output power correction coefficient, and optimizes the output power calculation method of the fuel cell system to calculate the output power of the power battery. Maintaining the value at startup avoids unnecessary charging, improves the economy of the system, and at the same time reduces the variable load on the fuel cell, prolongs the life of the fuel cell, and achieves more efficient energy management on the basis of ensuring the life of the fuel cell; on the basis of the energy management strategy based on a fixed time period, a road condition selection strategy is added to adapt to complex road conditions, which solves the shortcomings of traditional strategies that cannot adapt to complex and changeable road conditions, and optimizes the output power calculation method to maintain the stability of the power battery without frequently changing the stack load power; by setting the upper limit value for the power battery in the current road condition mode, overcharging of the power battery is avoided, which not only avoids energy waste but also prolongs the life of the power battery.

[0061] 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.

[0062] 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 fuel cell vehicle energy management method based on a fixed period, characterized in that: include: After the vehicle is started, it determines whether to start the fuel cell system based on the power battery SOC and current operating conditions; After the fuel cell system is started, the output power of the fuel cell system is determined based on the energy consumption in a fixed time period.

2. The method for energy management of a fuel cell vehicle based on a fixed period according to claim 1, characterized in that: After the vehicle is started, determining whether to start the fuel cell system is based on the power battery SOC and the current operating conditions, specifically including: According to the road condition mode, the opening state of the fuel cell system manual switch and the threshold value corresponding to the current SOC and different road condition modes Determine whether to start the fuel cell system.

3. The method for energy management of a fuel cell vehicle based on a fixed period according to claim 2, characterized in that: Thresholds corresponding to the different road condition modes include: and ,in, represents the upper limit value under the i-th road condition mode, represents the intermediate threshold value under the i-th road condition mode, Indicates the lower limit value under the i-th road condition mode.

4. The method for energy management of a fuel cell vehicle based on a fixed period of time according to claim 3, characterized in that: After the vehicle is started, determining whether to start the fuel cell system is based on the power battery SOC and the current operating conditions, specifically including: Step S11, start: first determine whether the high voltage of the vehicle is turned on, if it is turned on, go to step S12; otherwise, loop detection; Step S12, selecting a road condition mode: selecting different road condition modes according to different road conditions; Step S13, determining the state of the manual switch of the fuel cell system: if the manual switch is on, proceed to step S14, otherwise proceed to step S15; Step S14: Put the power battery Value and current traffic mode Upper limit For comparison: If the power battery The value is less than the current traffic mode Upper limit , the fuel cell system is started, and then the process returns to step S11; otherwise, the fuel cell system is not started, and the process returns to step S11; Step S15: Put the power battery The SOC lower limit value corresponding to the current road condition mode For comparison: If the power battery The value is less than the SOC lower limit corresponding to the current road condition mode , the fuel cell system is started, and then the process goes to step S16; otherwise, the fuel cell system is not started, and then the process goes back to step S11; Step S16: Put the power battery The middle threshold between the value and the current traffic mode For comparison: If the power battery The value is greater than the middle threshold corresponding to the current traffic mode , then turn off the fuel cell system and then return to step S11; otherwise, directly return to step S11.

5. The method for energy management of a fuel cell vehicle based on a fixed period of time according to claim 1, characterized in that: After the fuel cell system is started, the output power of the fuel cell system is determined according to the energy consumption in a fixed time period, specifically including: Calculate the average power consumption of the whole vehicle in the previous time period, and calculate the initial power demand based on the comparison result of the average power consumption of the whole vehicle in the previous time period with the idle power; optimize the initial power demand based on the fuel cell output power correction coefficient and the power difference correction coefficient to obtain the optimized power demand; determine the output power of the fuel cell system in the current time period based on the comparison result of the optimized power demand and the output power of the fuel cell system in the previous time period.

6. The method for energy management of a fuel cell vehicle based on a fixed period of time according to claim 5, characterized in that: After the fuel cell system is started, the output power of the fuel cell system is determined according to the energy consumption in a fixed time period, specifically including: Step S21, start: record the power battery initial value at the time of fuel cell system start-up. value , then proceed to step S22; Step S22: Power calculation: Calculate the average power consumption of the vehicle in the previous time period , then proceed to step S23; Step S23: according to the average power consumption of the vehicle in the previous time period and idling power The comparison results of the initial power requirement are calculated. :The average power consumption of the vehicle in the previous period and idling power The initial power requirement is compared with is the larger value of the two, and then proceeds to step S24; Step S24, calculate the power difference: use the initial power Subtract the current power Get the current With initial The difference ,like , the optimized required power is calculated by the following formula : ,in, represents the correction factor, With initial power demand Negative correlation, With the current With initial The difference positive correlation, then enter step S25; otherwise, the fuel cell system output power in the current time period Initial power requirement , return to step S22; Step S25, power comparison: according to the optimized required power Compared with the output power of the fuel cell system in the previous period The comparison result is used to determine the output power of the fuel cell system in the current time period: , then the output power of the fuel cell system in the current time period is , then returns to step S22; otherwise, the output power of the fuel cell system in the current time period is , then return to step S22.

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