Hydrogen fuel electric vehicle energy management method for prolonging service life of hydrogen fuel cell

Abstract

The invention relates to a hydrogen fuel electric vehicle energy management method capable of prolonging the service life of a hydrogen fuel cell, and belongs to the technical field of new energy vehicle control. Determining a hydrogen fuel cell engine power sequence and a power cell power sequence; determining a real hydrogen consumption sequence of the hydrogen fuel cell engine and an equivalent hydrogen consumption sequence of the power cell according to the hydrogen fuel cell engine power sequence and the power cell power sequence; weighting the real hydrogen consumption sequence to obtain a weighted hydrogen consumption sequence; and carrying out demand power distribution according to the weighted hydrogen consumption sequence and the equivalent hydrogen consumption sequence. Through the calculation method of weighting the real hydrogen consumption, the working interval distribution of the hydrogen fuel cell power can be optimized, and the time proportion of operation in the low-life power interval is reduced, so that the service life of the hydrogen fuel cell is prolonged.

Description

Technical Field

[0001] The invention relates to an energy management method for a hydrogen fuel cell electric vehicle for extending the life of a hydrogen fuel cell, and belongs to the technical field of new energy vehicle control. Background Art

[0002] Since hydrogen fuel cell hybrid vehicles have two power sources, power batteries and hydrogen fuel cell engines, the power required by the vehicle when driving is provided by the two, which needs to meet the real-time power demand of the working conditions. The power output characteristics of hydrogen fuel cell engines determine that the hydrogen fuel cell engine can effectively extend its service life by operating in a suitable working power range (such as the middle range of the hydrogen fuel cell engine power range), and a lower power change rate can also effectively extend its service life.

[0003] At present, fuel hybrid vehicles often use the equivalent fuel consumption minimum strategy (ECMS) based on fuel economy to distribute power between the two power sources of power batteries and hydrogen fuel cell engines. However, the existing ECMS strategy usually distributes the required power according to the minimum hydrogen consumption. Such a strategy mainly considers the economy of the vehicle and does not take into account the life of the hydrogen fuel cell. It is easy to cause the hydrogen fuel cell engine to work too long in the low life power range and the life loss is too fast. Summary of the invention

[0004] The purpose of the present invention is to provide a hydrogen fuel cell electric vehicle energy management method for extending the life of hydrogen fuel cells, and to achieve the purpose of increasing the life of hydrogen fuel cells by optimizing the working power range distribution of hydrogen fuel cells.

[0005] To achieve the above object, the present invention is implemented by adopting the following technical solutions: In a first aspect, the present invention provides a hydrogen fuel cell electric vehicle energy management method for extending the life of a hydrogen fuel cell, comprising: Obtain the startup time, running time and current power requirement of the hydrogen fuel cell engine; Determining the power range of the hydrogen fuel cell engine and the maximum power change rate of the hydrogen fuel cell engine according to the startup time and the running time; Determine the hydrogen fuel cell engine power sequence and the power battery power sequence according to the required power, the hydrogen fuel cell engine power range and the maximum power change rate; Determining a true hydrogen consumption sequence of the hydrogen fuel cell engine and an equivalent hydrogen consumption sequence of the power battery according to the hydrogen fuel cell engine power sequence and the power battery power sequence; The weighted hydrogen consumption sequence is weighted to obtain a weighted hydrogen consumption sequence; wherein, if the power of the hydrogen fuel cell engine belongs to the low life power range, it is determined that the weight of the real hydrogen consumption corresponding to the power is greater than the preset threshold value A1; otherwise, it is determined that the weight of the real hydrogen consumption corresponding to the power is equal to or less than the preset threshold value A1; A total hydrogen consumption sequence is determined according to the weighted hydrogen consumption sequence and the equivalent hydrogen consumption sequence, and an allocation amount is determined according to the minimum hydrogen consumption in the total hydrogen consumption sequence, and required power allocation is performed according to the allocation amount.

[0006] Optionally, determining the power range and maximum power change rate of the hydrogen fuel cell engine according to the startup time and the running time includes: Determining a startup type of the hydrogen fuel cell engine according to the startup time; According to the startup type and the operation duration, a power range and a maximum power change rate of the hydrogen fuel cell engine are determined.

[0007] Optionally, determining the startup type of the hydrogen fuel cell engine according to the startup time includes: If the startup time is within the time range of a hot engine startup, the startup type is determined to be a hot engine startup; If the startup time is within the time range of cold machine startup, the startup type is determined to be cold machine startup; If the startup time is within the time range of a low-temperature cold start, the startup type is determined to be a low-temperature cold start.

[0008] Optionally, determining the power range of the hydrogen fuel cell engine according to the startup type and the running time includes: If the start type is thermal engine start, determining the hydrogen fuel cell engine power range to be a first range; If the start type is a cold start: When the running time is less than or equal to the preset threshold value B1, the power range of the hydrogen fuel cell engine is determined to be a second range; When the running time is greater than the preset threshold value B1, the power range of the hydrogen fuel cell engine is determined to be the first range; If the startup type is a low temperature cold start: When the running time is less than or equal to the preset threshold value B1, the power range of the hydrogen fuel cell engine is determined to be a third range; When the preset threshold value B1 is less than the running time and less than the preset threshold value B2, the power range of the hydrogen fuel cell engine is determined to be the second range; When the running time is greater than the preset threshold value B2, the power range of the hydrogen fuel cell engine is determined to be the first range; The first range, the second range and the third range are narrowed successively, and the second range and the third range do not include a low life power interval.

[0009] Optionally, determining the maximum power change rate of the hydrogen fuel cell engine according to the startup type and the running time includes: If the startup type is thermal engine startup, determining the maximum power change rate to be a first change rate; If the start type is a cold start: When the running time is less than or equal to the preset threshold value B4, determining that the maximum power change rate is a second change rate; When the running time is greater than the preset threshold value B4, the maximum power change rate is determined to be the first change rate; If the startup type is a low temperature cold start: When the running time is less than or equal to the preset threshold value B4, the maximum power change rate is determined to be a third change rate; When the preset threshold value B4<operating time≤preset threshold value B4, the maximum power change rate is determined to be a second change rate; When the running time is greater than the preset threshold value B5, the maximum power change rate is determined to be the first change rate; The preset threshold value B4 is smaller than the preset threshold value B1, and the preset threshold value B5 is smaller than the preset threshold value B2; the first change rate, the second change rate and the third change rate decrease in sequence.

[0010] Optionally, determining the hydrogen fuel cell engine power sequence and the power battery power sequence according to the required power, the hydrogen fuel cell engine power range and the maximum power change rate includes: Determining a preliminary power sequence of the hydrogen fuel cell engine according to the power range and maximum power change rate of the hydrogen fuel cell engine; The power sequence of the power battery and the final power sequence of the hydrogen fuel cell engine are determined according to the required power and the preliminary power sequence of the hydrogen fuel cell engine.

[0011] Optionally, determining a preliminary power sequence of the hydrogen fuel cell engine according to the power range and the maximum power change rate of the hydrogen fuel cell engine comprises: Determining upper and lower power thresholds of the preliminary power sequence of the hydrogen fuel cell engine according to the power range of the hydrogen fuel cell engine; Determining the maximum power interval between adjacent sequence points in the hydrogen fuel cell engine power preliminary sequence according to the maximum power change rate; A preliminary power sequence of the hydrogen fuel cell engine is determined according to the upper and lower power thresholds and the maximum power interval.

[0012] Optionally, determining the power battery power sequence and the final hydrogen fuel cell engine power sequence according to the required power and the hydrogen fuel cell engine power preliminary sequence includes: Subtracting the initial power sequence of the hydrogen fuel cell from the required power to obtain the initial power sequence of the power battery; Comparing the preliminary power sequence of the power battery with a predetermined power battery power range, and removing sequence points in the preliminary power sequence that are outside the power battery power range to obtain the power battery power sequence; The final hydrogen fuel cell engine power sequence is determined according to the power battery power sequence.

[0013] Optionally, the method for determining the equivalent hydrogen consumption sequence of the power battery includes: Determining the corresponding relationship between the power of the power battery and the equivalent hydrogen consumption according to the power range of the hydrogen fuel cell; The equivalent hydrogen consumption sequence is determined according to the corresponding relationship and the power sequence of the power battery.

[0014] Optionally, determining the corresponding relationship between the power of the power battery and the equivalent hydrogen consumption according to the power range of the hydrogen fuel cell includes: If the hydrogen fuel cell power is within the first range, determining the corresponding relationship between the power battery power and the equivalent hydrogen consumption as a first corresponding relationship; otherwise, determining the corresponding relationship between the power battery power and the equivalent hydrogen consumption as a second corresponding relationship; Under the same power battery power, the equivalent hydrogen consumption obtained under the first corresponding relationship is greater than the equivalent hydrogen consumption obtained under the second corresponding relationship.

[0015] Optionally, the method further includes: acquiring the SOC of the power battery, and if the SOC is less than a preset threshold C1, determining the weight of the actual hydrogen consumption corresponding to the high power of the hydrogen fuel cell engine to be less than a preset threshold A1.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention performs weighted processing on the real hydrogen consumption sequence of the hydrogen fuel cell engine according to the power of the hydrogen fuel cell engine, and assigns a larger weight to the real hydrogen consumption corresponding to the power point in the low life power range. When the minimum hydrogen consumption strategy is used for power allocation, the proportion of these power points allocated will be significantly reduced, and accordingly, the proportion of the time that the hydrogen fuel cell engine runs in the low life power range will also be significantly reduced, thereby extending the service life of the hydrogen fuel cell engine.

[0017] 2. After the cold start or low-temperature cold start of the hydrogen fuel cell engine is completed, the present invention determines the working state of the hydrogen fuel cell engine by comparing it with a preset threshold value of the set running time, and determines the power range and maximum power change rate of the hydrogen fuel cell engine according to the working state of the hydrogen fuel cell engine, so as to take into account the life of the hydrogen fuel cell engine and the power economy of the whole vehicle.

[0018] 3. In the present invention, when the hydrogen fuel cell engine is in the best working state, the life loss of the hydrogen fuel cell engine is relatively small. At this time, the working restrictions on the hydrogen fuel cell engine are also small. The hydrogen fuel cell engine is used more to bear the required power, thereby saving hydrogen consumption without excessively affecting the life of the hydrogen fuel cell engine, so as to improve the economy of the whole vehicle.

[0019] 4. In the present invention, when the hydrogen fuel cell engine is in a non-optimal working state, the life of the hydrogen fuel cell engine is also depleted relatively quickly. In order to extend the life, the working restrictions on the hydrogen fuel cell engine are relatively large at this time, and the power battery system is used more to bear the required power, so as to extend the life of the hydrogen fuel cell engine while ensuring the power of the whole vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a flow chart of a hydrogen fuel cell electric vehicle energy management method for extending the life of a hydrogen fuel cell in Example 1; Figure 2 This is the relationship curve between the weight coefficient and the hydrogen fuel cell power in Example 1. DETAILED DESCRIPTION

[0021] It should be noted that: The technical solution of the present invention is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical solution of the present invention, rather than limitations on the technical solution of the present invention. The embodiments of the present invention and the technical features in the embodiments may be combined with each other unless there is a conflict.

[0022] The term "and / or" is only a description of the association relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " generally indicates that the related objects are in an "or" relationship. Example 1

[0023] Combination Figure 1 This embodiment introduces a hydrogen fuel cell electric vehicle energy management method for extending the life of a hydrogen fuel cell, the method comprising: Step S1, obtaining the startup time, operation time and current power requirement of the hydrogen fuel cell engine; The timing method of the startup time consumption is as follows: the timing starts from the time when the hydrogen fuel cell vehicle controller VCU sends a signal to start the hydrogen fuel cell, and ends when the startup completion signal is fed back by the hydrogen fuel cell controller FCU, so as to obtain the startup time consumption; The running time starts from the time when the start completion signal feedback from the hydrogen fuel cell controller FCU is received and ends until the current time; As for the required power, the vehicle control system VCU can collect the driver's accelerator pedal opening, brake pedal opening, brake switch, vehicle speed and gear position signals in real time, and the torque management module calculates the appropriate driving or braking torque. It also performs reasonable and necessary low-pass filtering on the torque, and then calculates the smoothed driver's required power (its value is unique at any time).

[0024] return Figure 1 , step S2, determining the power range and maximum power change rate of the hydrogen fuel cell engine according to the startup time and running time; Step S21, determining the startup type of the hydrogen fuel cell engine according to the startup time consumption; If the startup time is within the time range of a hot engine startup, the startup type is determined to be a hot engine startup; If the startup time is within the time range of cold machine startup, the startup type is determined to be cold machine startup; If the startup time is within the time range of a low-temperature cold start, the startup type is determined to be a low-temperature cold start.

[0025] In a specific embodiment, the time range for starting the hot engine is within 12 seconds, the time range for starting the cold engine is 12 seconds to 20 seconds, and the time range for starting at a low temperature is more than 500 seconds according to the third preset threshold; the above specific values ​​are only typical values ​​for each start type, and there may be differences according to the calibration values ​​of different vehicles.

[0026] Step S22, determining the power range and maximum power change rate of the hydrogen fuel cell engine according to the startup type and the running time; Step S221: If the start type is a thermal engine start, the power range of the hydrogen fuel cell engine is determined to be a first range, and the maximum power change rate is a first change rate; in a specific embodiment, the lower limit value of the first range is determined to be zero power, the upper limit value is determined to be the peak power that the hydrogen fuel cell engine can reach, and the first change rate is determined to be the maximum possible load change rate of the hydrogen fuel cell engine.

[0027] Step S222: If the startup type is cold startup: When the running time is less than or equal to the preset threshold value B1, the power range of the hydrogen fuel cell engine is determined to be a second range, and the maximum power change rate is a second change rate; When the running time is greater than the preset threshold value B1, it is determined that the power range of the hydrogen fuel cell engine is a first range, and the maximum power change rate is a first change rate; The second range does not include the low life power interval to optimize the distribution of the operating power interval of the hydrogen fuel cell engine. The low life power interval can be obtained according to the actual vehicle calibration, and generally includes a low power interval and a high power interval within the power range of the hydrogen fuel cell engine; in a specific embodiment, the low life power interval is selected below the idle power and above 85% of the rated power.

[0028] In a specific embodiment, the lower limit of the second range is determined as the idle power, and the upper limit is determined as 85% of the rated power; the second change rate is determined as 75% of the maximum possible load change rate, and the preset threshold B1 can be determined as 150 seconds.

[0029] In a specific embodiment, when the cold engine is started, the power range and the maximum power change rate of the hydrogen fuel cell engine are not adjusted synchronously; the power range of the hydrogen fuel cell engine is still adjusted according to the preset threshold value B1; the maximum power change rate is determined according to the preset threshold value B4, specifically: When the running time is less than or equal to the preset threshold value B4, the maximum power change rate is determined to be a second change rate; When the running time is greater than the preset threshold value B4, the maximum power change rate is determined to be the first change rate; The preset threshold value B4 is less than the preset threshold value B1, so that the maximum power change rate can precede the change of the power range to respond to the load change demand in advance. The period of preset threshold value B4 < operation time < preset threshold value B1 can be understood as a transition period before the power range is fully released. During this period of time, the maximum power change rate is released in advance to enable the hydrogen fuel cell engine to pre-adapt and better recover to the optimal working state. The preset threshold value B4 can be set to a typical value of 120 seconds.

[0030] Specifically, when the power range and the maximum power change rate of the hydrogen fuel cell engine are adjusted synchronously, whether the hydrogen fuel cell engine reaches the optimal working state is judged according to the startup type and the preset threshold value of the power range of the hydrogen fuel cell engine.

[0031] Before the cold engine start-up running time reaches the preset threshold value B1, the hydrogen fuel cell engine is still in a transition stage after starting and has not reached the optimal working state. Therefore, the second range is used to limit the hydrogen fuel cell to operate in a limited power range with a relatively high remaining life, and the limitation of the maximum power change rate can also reduce the situation of rapid load changes, thereby reducing the adverse effects on the life of the hydrogen fuel cell. Accordingly, when the hydrogen fuel cell engine has not reached the optimal working state, the power battery system will bear more of the required power to ensure the power of the entire vehicle. That is, in this embodiment, in order to extend the life of the hydrogen fuel cell engine, it is carried out without affecting the normal driving of the vehicle.

[0032] When the cold engine start-up running time reaches the preset threshold value B1, the hydrogen fuel cell engine reaches the optimal working state, and the life loss of the hydrogen fuel cell engine during operation is relatively reduced, so that the power range and maximum power change rate of the hydrogen fuel cell engine are adjusted to the same as the corresponding values ​​of the hot engine start-up. When the hydrogen fuel cell engine is in the optimal working state, the hydrogen fuel cell engine will bear more of the required power, thereby reducing hydrogen consumption without affecting the life too much, so as to improve the economy of the whole vehicle.

[0033] Step S223: If the startup type is a low temperature cold start: When the running time is less than or equal to the preset threshold value B1, the power range of the hydrogen fuel cell engine is determined to be a third range, and the maximum power change rate is a third change rate; When the preset threshold value B1 is less than the running time and less than the preset threshold value B2, it is determined that the power range of the hydrogen fuel cell engine is the second range, and the maximum power change rate is the second change rate; When the running time is greater than the preset threshold value B2, it is determined that the power range of the hydrogen fuel cell engine is a first range, and the maximum power change rate is a first change rate; The second range and the third range do not include a low life power interval. The low life power interval can be obtained according to actual vehicle calibration, and usually includes a low power interval and a high power interval within the power range of the hydrogen fuel cell engine.

[0034] In a specific embodiment, the lower limit of the third range is 20% of the rated power, and the upper limit is 70% of the rated power. The third change rate is 50% of the maximum possible load change rate. The preset threshold B2 can be set to a typical value of 300 seconds. The preset threshold B3 can be set to a typical value of 450 seconds.

[0035] In a specific embodiment, during low-temperature cold start, the power range and the maximum power change rate of the hydrogen fuel cell engine are not adjusted synchronously; the power range of the hydrogen fuel cell engine is still adjusted according to the preset threshold value B1 and the preset threshold value B2; the maximum power change rate is determined according to the preset threshold value B4 and the preset threshold value B5, specifically: When the running time is less than or equal to the preset threshold value B4, the maximum power change rate is determined to be a third change rate; When the preset threshold value B4 is less than the running time and less than the preset threshold value B5, the maximum power change rate is determined to be the second change rate; When the running time is greater than the preset threshold value B5, the maximum power change rate is determined to be the first change rate; The preset threshold value B4 is less than the preset threshold value B1, and the preset threshold value B5 is less than the preset threshold value B2, so that the maximum power change rate can be adjusted before the power range to respond to a larger load change demand in advance. The early release of the maximum power change rate limit can prompt the hydrogen fuel cell engine to pre-adapt and better restore to the optimal working state. The preset threshold value B4 can be set to a typical value of 240 seconds, and the preset threshold value B5 can be set to a typical value of 400 seconds.

[0036] After a low-temperature cold start, it takes a long time for the hydrogen fuel cell engine to recover to the optimal working state. Therefore, this embodiment divides this transition time into two stages, gradually expanding the power range and maximum power change rate of the hydrogen fuel cell engine to the same level as the hot engine start. The hydrogen fuel cell engine also reaches the optimal working state, thereby ensuring the power requirements of the entire vehicle without causing significant life loss, thereby reducing hydrogen consumption.

[0037] Step S3, determining a hydrogen fuel cell engine power sequence and a power battery power sequence according to the required power, the hydrogen fuel cell engine power range and the maximum power change rate; Step S31, determining a preliminary power sequence of the hydrogen fuel cell engine according to the power range and maximum power change rate of the hydrogen fuel cell engine; Step S311, determining upper and lower power thresholds of the preliminary power sequence of the hydrogen fuel cell engine according to the power range of the hydrogen fuel cell engine; Step S312, determining the maximum power interval between adjacent sequence points in the preliminary power sequence of the hydrogen fuel cell engine according to the maximum power change rate; Step S313: Determine the preliminary power sequence of the hydrogen fuel cell engine according to the upper and lower power thresholds, the maximum power interval and the preset sequence interval. Within the power range of the hydrogen fuel cell engine, determine the power sequence of the hydrogen fuel cell engine with a sequence interval below the maximum power change rate, and the sequence interval is usually between 2kW and 10kW.

[0038] In the previous step, the power range and maximum power change rate of the hydrogen fuel cell engine have been determined. The core strategy of the method described in this embodiment is that when the hydrogen fuel cell engine is in the best working state, the life loss is relatively slow. At this time, there are no major restrictions on the power range and the maximum power change rate. The hydrogen fuel cell engine can sometimes operate within a power range with low life but high power, so that the hydrogen fuel cell engine can bear more of the required power without losing its life too quickly.

[0039] When the hydrogen fuel cell engine has not reached the optimal working state, its life loss is relatively fast. At this time, the power range and maximum power change rate are greatly restricted, limiting the hydrogen fuel cell engine to operate only in a limited power range (excluding the low life power range). The working power range distribution of the hydrogen fuel cell engine is optimized to reduce the adverse effects of the hydrogen fuel cell engine operating in the low life power range or rapid load changes on life loss. The power battery system bears more of the required power to ensure the power of the entire vehicle.

[0040] Step S32, determining a power battery power sequence and a final hydrogen fuel cell engine power sequence according to the required power and the preliminary hydrogen fuel cell engine power sequence; Step S321, subtracting the initial power sequence of the hydrogen fuel cell starting power from the required power to obtain the initial power sequence of the power battery; Step S322: Compare the preliminary power sequence of the power battery with a predetermined power battery power range, and remove sequence points in the preliminary power sequence that are beyond the power battery power range to obtain the power battery power sequence; Step S323: determining, according to the power battery power sequence, a final hydrogen fuel cell engine power sequence corresponding one-to-one to the power battery power sequence.

[0041] The method for obtaining the predetermined power battery power range is as follows: the hydrogen fuel cell vehicle controller VCU receives the total power battery voltage, the allowable real-time pulse discharge current limit, the allowable real-time pulse charging current limit, the allowable real-time continuous discharge current limit and the allowable real-time continuous charging current limit sent in real time by the power battery management system BMS through the CAN network, thereby calculating the allowable discharge power limit value and determining the power battery power range according to the allowable discharge power limit value.

[0042] return Figure 1 , step S4, determining a real hydrogen consumption sequence of the hydrogen fuel cell engine and an equivalent hydrogen consumption sequence of the power battery according to the hydrogen fuel cell engine power sequence and the power battery power sequence; Step S41, determining a real hydrogen consumption sequence of the hydrogen fuel cell engine according to the hydrogen fuel cell engine power sequence; By looking up the hydrogen fuel cell engine powers in the hydrogen fuel cell engine power sequence in a table one by one, the corresponding actual hydrogen consumption can be determined, thereby determining the actual hydrogen consumption sequence; the relationship table between the two is obtained in advance; Step S42: determining an equivalent hydrogen consumption sequence of the power battery according to the power battery power sequence; The corresponding equivalent hydrogen consumption factor can be determined by looking up the power battery power in the power battery power sequence one by one, and the corresponding relationship between the power battery power and the equivalent hydrogen consumption can be determined according to the equivalent hydrogen consumption factor and the power battery power, so as to determine the final equivalent hydrogen consumption sequence. The relationship table between the two is obtained in advance; return Figure 1 , step S5, weighting the actual hydrogen consumption sequence to obtain a weighted hydrogen consumption sequence; wherein, if the hydrogen fuel cell engine power belongs to the low life power range, then determine that the weight of the actual hydrogen consumption corresponding to the power is greater than a preset threshold value A1; otherwise, determine that the weight of the actual hydrogen consumption corresponding to the power is equal to or less than the preset threshold value A1; the preset threshold value A1 here is usually set to 1, and other values ​​can also be selected according to the control strategy.

[0043] Step S6: determine a total hydrogen consumption sequence according to the weighted hydrogen consumption sequence and the equivalent hydrogen consumption sequence, determine an allocation amount according to the minimum hydrogen consumption in the total hydrogen consumption sequence, and perform required power allocation according to the allocation amount.

[0044] In the aforementioned steps, the operation of the hydrogen fuel cell engine has been restricted by adjusting the power range and the maximum power change rate. In this step, the operation of the hydrogen fuel cell engine is further optimized and adjusted in a weighted manner.

[0045] Specifically, in this embodiment, a weight greater than a preset threshold value A1 is assigned to the actual hydrogen consumption corresponding to the power within the low life power range of the hydrogen fuel cell engine. In this way, when determining the allocation amount based on the minimum hydrogen consumption, the allocation strategy will tend to allocate the required power to the hydrogen fuel cell engine power outside the low life power range, thereby reducing the proportion of the working time of the hydrogen fuel cell engine in the low life power range, thereby further improving the working condition of the hydrogen fuel cell engine to delay life attenuation.

[0046] Combination Figure 2 In a specific embodiment, each hydrogen consumption point in the weighted hydrogen consumption sequence is assigned a weight coefficient according to the corresponding hydrogen fuel cell engine power. The relationship curve between the hydrogen fuel cell engine power and the weight coefficient is as follows: Figure 2As shown in Figure 2, different relationship curves can obtain different weighted hydrogen consumption sequences, and the allocation results obtained in the minimum hydrogen consumption strategy are also different accordingly. For example, Figure 2 Curve 2 in the figure represents that when the power battery is working limited, the weight of the actual hydrogen consumption corresponding to the hydrogen fuel cell engine power is all lowered relative to Curve 1 under normal conditions, so that when allocating power, the minimum hydrogen consumption strategy will be more inclined to allocate the required power to the hydrogen fuel cell engine. The hydrogen fuel cell engine can bear more allocation to meet the power demand of the entire vehicle when the power battery is working limited.

[0047] In a specific embodiment, the weighted processing of the actual hydrogen consumption sequence is also related to the SOC of the power battery. If the SOC is less than a preset threshold C1 (which can be set to a typical value of 30%, and the specific value can be flexibly set according to the specific working conditions), the weight distribution of power points in the low-life power range can be further refined, and the weight coefficients of the actual hydrogen consumption corresponding to the high power points in the low-life power range are all determined to be less than the preset threshold A1.

[0048] Therefore, when the minimum hydrogen consumption strategy is used for power allocation, these high power points are allocated with a higher priority due to their low corresponding weighted hydrogen consumption, so as to ensure the power of the whole vehicle when the power of the power battery is limited.

[0049] The allocation amount obtained in step S6 will be sent to the vehicle controller VCU. The vehicle controller VCU will receive the allocation amount in response to the power demand signal before each control cycle, and send the allocation amount to the hydrogen fuel cell engine and the power battery for control. Example 2

[0050] The present embodiment is different from the present embodiment in that: the method for determining the equivalent hydrogen consumption sequence of the power battery in the present embodiment includes: Determining the corresponding relationship between the power of the power battery and the equivalent hydrogen consumption according to the power range of the hydrogen fuel cell; If the hydrogen fuel cell power is within the first range, it is proved that the hydrogen fuel cell engine is in the best working state, and the corresponding relationship between the power battery power and the equivalent hydrogen consumption is determined to be the first corresponding relationship; otherwise, the hydrogen fuel cell engine is in a transition state, and the corresponding relationship between the power battery power and the equivalent hydrogen consumption is determined to be the second corresponding relationship; Under the same power battery power, the equivalent hydrogen consumption obtained under the first corresponding relationship is greater than the equivalent hydrogen consumption obtained under the second corresponding relationship.

[0051] The purpose of such determination is that when the hydrogen fuel cell engine is in the best working state, the power range of the hydrogen fuel cell engine is large, the maximum power change rate is high, and the life loss is relatively slow; at this time, the power response speed of the hydrogen fuel cell engine is fast and it can also properly operate in the low life power range to meet the vehicle power requirements, and the actual hydrogen consumption of the direct output power of the hydrogen fuel cell engine is lower than that of the power battery. At this time, the equivalent hydrogen consumption corresponding to the power battery can be fully adjusted through the first corresponding relationship, so that the hydrogen fuel cell engine will be allocated more allocations under the minimum hydrogen consumption allocation strategy, so as to make more use of the hydrogen fuel cell engine in the best working state to meet the vehicle power requirements and reduce hydrogen consumption.

[0052] When the hydrogen fuel cell engine is in a transitional state before a non-optimal working state, the power range of the hydrogen fuel cell engine is small, the maximum power change rate is low, and the life loss is relatively fast. At this time, the hydrogen fuel cell engine is limited to operate only within a small power range of high life and normal life, and the power response capability is relatively poor. At this time, the equivalent hydrogen consumption corresponding to the power of the power battery can be comprehensively reduced through the second corresponding relationship, so that the power battery bears more allocation under the minimum hydrogen consumption allocation strategy to ensure the vehicle's power when the hydrogen fuel cell engine is limited.

[0053] In general, the methods in this embodiment are all aimed at extending the service life of the hydrogen fuel cell engine and improving the economy of the whole vehicle as much as possible under the premise of ensuring sufficient power of the whole vehicle, and are more feasible.

[0054] In a specific embodiment, the calculation formulas for the equivalent hydrogen consumption under the first corresponding relationship and the second corresponding relationship are both:

[0055] In the formula, s act represents the instantaneous equivalent hydrogen consumption factor of the power battery; SOC(t) represents the actual SOC value of the power battery; t represents the time; s0 represents the constant part of the instantaneous equivalent hydrogen consumption factor; K1 and K2 represent the coefficients of the instantaneous equivalent hydrogen consumption factor; SOC ref Indicates the control reference value of the power battery SOC; Indicates the instantaneous equivalent hydrogen consumption of the power battery; Indicates the lower calorific value of hydrogen; u indicates the control signal; Indicates the efficiency of the power battery charging and discharging path system; Indicates the power of the power battery; Among them, SOC ref Indicates the control reference value of the power battery SOC. Under different control strategies, SOC ref The value of SOC is different. For example, in the power maintenance stage (CS), SOCref The value of is a fixed value, and the SOC of the power battery is controlled to fluctuate within a range around the fixed value. For example, in hybrid mode, the SOC of the power battery cannot be controlled within a range. ref The value of is a variable value that changes with the mileage of the trip.

[0056] Among them, the value of the constant part s0 of the equivalent hydrogen consumption factor and the value of the coefficient K1 of the instantaneous equivalent hydrogen consumption factor under the first corresponding relationship are both greater than the values ​​of the corresponding parameters under the second corresponding relationship.

[0057] As typical values, in the first corresponding relationship, s0 takes a value of 2.1, and K1 takes a value of 4.9. In the second corresponding relationship, s0 takes a value of 1.3, and K1 takes a value of 3.

[0058] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0059] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0060] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0061] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0062] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the enlightenment of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which all fall within the protection of the present invention.

Claims

1. A hydrogen fuel cell electric vehicle energy management method for extending the life of a hydrogen fuel cell, characterized in that: The method comprises: Obtain the startup time, running time and current power requirement of the hydrogen fuel cell engine; Determining the power range of the hydrogen fuel cell engine and the maximum power change rate of the hydrogen fuel cell engine according to the startup time and the running time; Determine the hydrogen fuel cell engine power sequence and the power battery power sequence according to the required power, the hydrogen fuel cell engine power range and the maximum power change rate; Determining a true hydrogen consumption sequence of the hydrogen fuel cell engine and an equivalent hydrogen consumption sequence of the power battery according to the hydrogen fuel cell engine power sequence and the power battery power sequence; The weighted hydrogen consumption sequence is weighted to obtain a weighted hydrogen consumption sequence; wherein, if the power of the hydrogen fuel cell engine belongs to the low life power range, it is determined that the weight of the real hydrogen consumption corresponding to the power is greater than the preset threshold value A1; otherwise, it is determined that the weight of the real hydrogen consumption corresponding to the power is equal to or less than the preset threshold value A1; A total hydrogen consumption sequence is determined according to the weighted hydrogen consumption sequence and the equivalent hydrogen consumption sequence, and an allocation amount is determined according to the minimum hydrogen consumption in the total hydrogen consumption sequence, and required power allocation is performed according to the allocation amount.

2. The hydrogen fuel cell electric vehicle energy management method for extending the life of a hydrogen fuel cell according to claim 1, characterized in that: Determining the power range and maximum power change rate of the hydrogen fuel cell engine according to the startup time and the running time includes: Determining a startup type of the hydrogen fuel cell engine according to the startup time; According to the startup type and the operation duration, a power range and a maximum power change rate of the hydrogen fuel cell engine are determined.

3. The hydrogen fuel cell electric vehicle energy management method for extending the life of a hydrogen fuel cell according to claim 2, characterized in that: Determining the startup type of the hydrogen fuel cell engine according to the startup time includes: If the startup time is within the time range of a hot engine startup, the startup type is determined to be a hot engine startup; If the startup time is within the time range of cold machine startup, the startup type is determined to be cold machine startup; If the startup time is within the time range of a low-temperature cold start, the startup type is determined to be a low-temperature cold start.

4. The hydrogen fuel cell electric vehicle energy management method for extending the life of a hydrogen fuel cell according to claim 3, characterized in that: Determining the power range of the hydrogen fuel cell engine according to the startup type and the running time includes: If the start type is thermal engine start, determining the hydrogen fuel cell engine power range to be a first range; If the start type is a cold start: When the running time is less than or equal to the preset threshold value B1, the power range of the hydrogen fuel cell engine is determined to be a second range; When the running time is greater than the preset threshold value B1, the power range of the hydrogen fuel cell engine is determined to be the first range; If the startup type is a low temperature cold start: When the running time is less than or equal to the preset threshold value B1, the power range of the hydrogen fuel cell engine is determined to be a third range; When the preset threshold value B1 is less than the running time and less than the preset threshold value B2, the power range of the hydrogen fuel cell engine is determined to be the second range; When the running time is greater than the preset threshold value B2, the power range of the hydrogen fuel cell engine is determined to be the first range; The first range, the second range and the third range are narrowed successively, and the second range and the third range do not include a low life power interval.

5. The hydrogen fuel cell electric vehicle energy management method for extending the life of a hydrogen fuel cell according to claim 4, characterized in that: Determining the maximum power change rate of the hydrogen fuel cell engine according to the startup type and the running time includes: If the startup type is thermal engine startup, determining the maximum power change rate to be a first change rate; If the start type is a cold start: When the running time is less than or equal to the preset threshold value B4, determining that the maximum power change rate is a second change rate; When the running time is greater than the preset threshold value B4, the maximum power change rate is determined to be the first change rate; If the startup type is a low temperature cold start: When the running time is less than or equal to the preset threshold value B4, the maximum power change rate is determined to be a third change rate; When the preset threshold value B4<operating time≤preset threshold value B4, the maximum power change rate is determined to be a second change rate; When the running time is greater than the preset threshold value B5, the maximum power change rate is determined to be the first change rate; The preset threshold value B4 is smaller than the preset threshold value B1, and the preset threshold value B5 is smaller than the preset threshold value B2; the first change rate, the second change rate and the third change rate decrease in sequence.

6. The hydrogen fuel cell electric vehicle energy management method for extending the life of a hydrogen fuel cell according to claim 1, characterized in that: Determining the hydrogen fuel cell engine power sequence and the power battery power sequence according to the required power, the hydrogen fuel cell engine power range and the maximum power change rate includes: Determining a preliminary power sequence of the hydrogen fuel cell engine according to the power range and maximum power change rate of the hydrogen fuel cell engine; The power sequence of the power battery and the final power sequence of the hydrogen fuel cell engine are determined according to the required power and the preliminary power sequence of the hydrogen fuel cell engine.

7. The hydrogen fuel cell electric vehicle energy management method for extending the life of a hydrogen fuel cell according to claim 6, characterized in that: Determining the preliminary power sequence of the hydrogen fuel cell engine according to the power range and the maximum power change rate of the hydrogen fuel cell engine comprises: Determining upper and lower power thresholds of the preliminary power sequence of the hydrogen fuel cell engine according to the power range of the hydrogen fuel cell engine; Determining the maximum power interval between adjacent sequence points in the hydrogen fuel cell engine power preliminary sequence according to the maximum power change rate; A preliminary power sequence of the hydrogen fuel cell engine is determined according to the upper and lower power thresholds and the maximum power interval.

8. The hydrogen fuel cell electric vehicle energy management method for extending the life of a hydrogen fuel cell according to claim 7, characterized in that: The step of determining the power sequence of the power battery and the final power sequence of the hydrogen fuel cell engine according to the required power and the preliminary power sequence of the hydrogen fuel cell engine comprises: Subtracting the initial power sequence of the hydrogen fuel cell from the required power to obtain the initial power sequence of the power battery; Comparing the preliminary power sequence of the power battery with a predetermined power battery power range, and removing sequence points in the preliminary power sequence that are outside the power battery power range to obtain the power battery power sequence; The final hydrogen fuel cell engine power sequence is determined according to the power battery power sequence.

9. The hydrogen fuel cell electric vehicle energy management method for extending the life of a hydrogen fuel cell according to claim 4, characterized in that: The method for determining the equivalent hydrogen consumption sequence of the power battery includes: Determining the corresponding relationship between the power of the power battery and the equivalent hydrogen consumption according to the power range of the hydrogen fuel cell; If the hydrogen fuel cell power is within the first range, determining the corresponding relationship between the power battery power and the equivalent hydrogen consumption as a first corresponding relationship; otherwise, determining the corresponding relationship between the power battery power and the equivalent hydrogen consumption as a second corresponding relationship; Under the same power battery power, the equivalent hydrogen consumption obtained under the first corresponding relationship is greater than the equivalent hydrogen consumption obtained under the second corresponding relationship; The equivalent hydrogen consumption sequence is determined according to the corresponding relationship and the power sequence of the power battery.

10. The hydrogen fuel cell electric vehicle energy management method for extending the life of a hydrogen fuel cell according to claim 1, characterized in that: The method further includes: obtaining the SOC of the power battery, and if the SOC is less than a preset threshold value C1, determining the weight of the actual hydrogen consumption corresponding to the high power of the hydrogen fuel cell engine to be less than a preset threshold value A1.

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