Hydrogen fuel cell start-stop control method and device of hydrogen fuel cell vehicle

Abstract

The invention relates to a hydrogen fuel cell start-stop control method and device of a hydrogen fuel cell vehicle, and belongs to the technical field of hydrogen fuel cell vehicle control. The method comprises the following steps: acquiring a starting duration estimated value and a shutdown duration estimated value of the hydrogen fuel cell; determining a power limited SOC threshold value SOCend of the power battery according to the temperature of the power battery; determining an SOC threshold value SOCFCon for starting the hydrogen fuel cell; and an SOC threshold value SOCFCoff; and when the SOC of the power battery is between the SOCFCon and the SOCFCoff, starting the hydrogen fuel battery in response to the condition that the SOC of the power battery is reduced to the SOCFCon, and closing the hydrogen fuel battery in response to the condition that the SOC of the power battery is increased to the SOCFCoff. According to the starting and stopping method, the starting and stopping time of the hydrogen fuel cell can be reasonably determined, it can be guaranteed that the hydrogen fuel cell has enough time to be started before the SOC is reduced to the SOC end by setting the threshold SOCon and the threshold SOCoff, the power requirement of the whole vehicle is met, and frequent starting and stopping caused by large SOC fluctuation are avoided.

Description

Technical Field

[0001] The present invention relates to a hydrogen fuel cell start-stop control method and device for a hydrogen fuel cell vehicle, belonging to the technical field of hydrogen fuel cell vehicle control. Background Art

[0002] Since hydrogen fuel cell hybrid vehicles have two power sources, power batteries and hydrogen fuel cells, the vehicle's driving power is provided by both, which needs to meet the real-time needs of the operating conditions. The main feature of the operating conditions of hydrogen fuel cell hybrid vehicles is that the real-time dynamic changes in the power demand of the entire vehicle are relatively rapid, especially in urban operating conditions where starting, stopping, deceleration, and braking are more frequent. Variable loads, starting and stopping, idling, and high loads all have a great impact on the life of hydrogen fuel cells. Frequent load changes have the largest impact on the life of hydrogen fuel cells in the operating conditions, followed by starting and stopping. If the strategy of hydrogen fuel cell power following the power demand of the entire vehicle is adopted, the hydrogen fuel cell will inevitably work in a dynamic variable load state all the time.

[0003] Therefore, for the purpose of protecting hydrogen fuel cells, the control strategy will limit the power change rate and power usage range to reduce the life decay rate, and the faster power request changes will be responded to by the power battery. However, this may lead to a larger fluctuation range of the battery SOC ("State of Charge", which represents the percentage of electricity stored in the power battery) under different working conditions, and it is more likely to cause the problem of frequent triggering of hydrogen fuel cell start and stop. Frequent start and stop also have a significant impact on the reduction of hydrogen fuel cell life.

[0004] When a hydrogen fuel cell hybrid vehicle adopts an auxiliary range-extending energy management strategy, it runs in pure electric mode during the charging of depleting (CD) phase; when the power drops to the target limit, it switches to the charging of sustaining (CS) phase and runs in hydrogen hybrid mode, and the hydrogen fuel cell keeps the power battery SOC relatively stable. When the hybrid mode (Blended) range-extending control strategy is adopted, there is no independent pure electric driving mode CD phase, and the hydrogen fuel cell always runs intermittently.

[0005] When the vehicle controller VCU issues a start-stop request, the start-up and shutdown process of the hydrogen fuel cell is completely controlled by the FCU independently. The completion time is not determined by the VCU. The VCU can only decide to issue a start-stop request at the right time. What is more serious is that the start-stop of the hydrogen fuel cell is greatly affected by temperature. The time for hot engine start-up, cold engine start-up and low-temperature cold start, normal temperature shutdown and low temperature shutdown are generally much higher than the internal combustion engine range extension system. The start-stop of the internal combustion engine is generally around 1 second. The shortest start-up of the hydrogen fuel cell - hot engine start-up to rated power is more than 10 seconds, and the shortest shutdown of the hydrogen fuel cell - normal temperature shutdown is about 180 seconds. Therefore, frequent starts and stops may be impossible for the hydrogen fuel cell to respond in time.

[0006] At present, fuel hybrid vehicles often adopt the Equivalent Consumption Minimum Strategy (ECMS) based on fuel economy, which is an instantaneous optimization method that can be applied to hydrogen fuel cell hybrid electric vehicles. However, the general ECMS mainly affects the economy by calculating the equivalent hydrogen consumption of the power of the power battery, and does not take into account how to solve the problem of extending the service life of the hydrogen fuel cell. The control process is prone to cause the hydrogen fuel cell to start and stop frequently, idle or run at high power, which is not good for the life of the hydrogen fuel cell. The ECMS strategy limits the power usage range and the power change rate, and also needs to reasonably control the start and stop of the hydrogen fuel cell. Type the instruction manual title here Summary of the invention

[0007] The purpose of the present invention is to achieve the technical effect of reducing the number of starts and stops of hydrogen fuel cells by optimizing the control strategy for starting and stopping hydrogen fuel cells.

[0008] 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 start-stop control method for a hydrogen fuel cell vehicle, wherein the hydrogen fuel cell vehicle comprises a hydrogen fuel cell and a power battery; the method comprises: Determining an estimated startup duration and an estimated shutdown duration of the hydrogen fuel cell according to the ambient temperature of the hydrogen fuel cell vehicle and the temperature of the hydrogen fuel cell; According to the rated power consumption of the hydrogen fuel cell vehicle and the estimated startup time, the power consumption of the power battery is calculated to be reduced to the power limit threshold SOC end The SOC threshold SOC that can complete the start-up of the hydrogen fuel cell FCon ; According to the rated power consumption of the hydrogen fuel cell vehicle, the estimated startup time and the estimated shutdown time of the hydrogen fuel cell, the power consumption of the power battery is calculated to be reduced to the power limiting threshold SOC end The SOC threshold SOC at which a hydrogen fuel cell shutdown can be completed once and a hydrogen fuel cell startup can be completed again FCoff ; When the power battery is in working state and the SOC of the power battery is at SOC FCon and SOC FCoff In between, In response to the SOC of the power battery decreasing to the SOC FCon , starting the hydrogen fuel cell, and In response to the SOC of the power battery rising to the SOC FCoff , shut down the hydrogen fuel cell.

[0009] Optionally, obtaining the estimated value of the start-up time of the hydrogen fuel cell according to the ambient temperature of the hydrogen fuel cell vehicle and the temperature of the hydrogen fuel cell includes: Determining the startup type of the hydrogen fuel cell according to the ambient temperature of the hydrogen fuel vehicle and the temperature of the hydrogen fuel cell; Obtaining an estimated startup duration of the hydrogen fuel cell according to a startup type of the hydrogen fuel cell; The startup types include hot engine startup, cold engine startup and low temperature cold startup: The calculation formula for the estimated value of the startup time when the hot engine is started is: ; In the formula, △T on1 Indicates the estimated startup time when the hot engine is started; T on1 Indicates the preset hot engine startup time; k on1 Indicates the preset heat engine startup time adjustment proportional factor; The calculation formula for the estimated startup time when starting a cold machine is: ; In the formula, △T on2 Indicates the estimated startup time when the cold machine is started; T on2 Indicates the preset cold machine startup time; k on2 Indicates the preset cold machine startup time adjustment proportional factor; The calculation formula for the estimated startup time during low temperature cold start is: ; In the formula, △T on3 Indicates the estimated time of low temperature cold start; T on3 Indicates the preset low temperature cooling machine startup time; k on3 Indicates the preset low-temperature refrigerator startup time adjustment proportional factor; The estimated startup duration value corresponds to the ΔT according to the determined startup type. on1 , △T on2 , △T on3 One of them.

[0010] Optionally, obtaining the shutdown duration estimate of the hydrogen fuel cell according to the ambient temperature of the hydrogen fuel cell vehicle and the temperature of the hydrogen fuel cell includes: Determining a shutdown type of the hydrogen fuel cell according to the ambient temperature of the hydrogen fuel cell vehicle and the temperature of the hydrogen fuel cell; Obtaining an estimated shutdown duration of the hydrogen fuel cell according to a shutdown type of the hydrogen fuel cell; Wherein, the shutdown types include normal temperature shutdown and low temperature shutdown; The calculation formula for the estimated shutdown time when shutting down at normal temperature is: ; In the formula, △T off1 Indicates the estimated shutdown time when shutting down at normal temperature; T off1 Indicates the preset normal temperature shutdown time; k off1 Indicates the preset normal temperature shutdown time adjustment proportional factor; The calculation formula for the estimated shutdown time during low temperature shutdown is: ; In the formula, △T off2 Indicates the estimated shutdown time when the low temperature is turned off; T off2 Indicates the preset low temperature shutdown time; k off2 Indicates the preset low temperature shutdown time adjustment proportional factor; The shutdown duration estimation value corresponds to the ΔT according to the shutdown type determined. off1 , △T off2 One of them.

[0011] Optionally, in response to the SOC of the power battery decreasing to the SOC FCon Before starting the hydrogen fuel cell, determine the shutdown time △T of the hydrogen fuel cell when the power battery is working alone. FCoff Is it greater than or equal to the limit value T FCoff , ; If the judgment is yes, the hydrogen energy battery is started; if the judgment is no, the hydrogen energy battery is not started; Where T FCoff The calculation formula is: ; In the formula, k T1 Indicates the preset minimum downtime adjustment factor of the hydrogen fuel cell, 1.0≤ k T1 ≤2, T off1 Indicates the pre-acquired normal temperature shutdown time.

[0012] Optionally, in response to the SOC of the power battery rising to the SOC FCoff Before shutting down the hydrogen fuel cell, it is determined that when the power battery and the hydrogen fuel cell work together, the working time △T of the hydrogen fuel cell FCon Is it greater than or equal to T? FCon , ; If the judgment is yes, the hydrogen energy battery is turned off; if the judgment is no, the hydrogen energy battery is not turned off; Where T FCon The calculation formula used is: ;k T2Indicates the preset minimum operating time adjustment scale factor of the hydrogen fuel cell, 0.9≤k T2 ≤2; Indicates the sum of the pre-acquired hot machine startup time and normal temperature shutdown time.

[0013] Optionally, the hydrogen fuel cell vehicle has a battery maintenance mode, in which the SOC of the power battery is controlled to fluctuate within a control range, and in which: The SOC FCon The calculation formula is: ; In the formula, SOC end Indicates the power-limited SOC threshold of the power battery; Q b Indicates the power battery capacity; V oc Indicates the power battery voltage; P d Indicates the rated power of the drive system. P ac Indicates the rated power of the accessory system. The rated power consumption of the hydrogen fuel cell vehicle is the sum of the rated power of the drive system and the rated power of the accessory system; T on Indicates the estimated startup time; The SOC FCoff The calculation formula is: ; In the formula, SOC end Indicates the power-limited SOC threshold of the power battery; Q b Indicates the power battery capacity; V oc Indicates the power battery voltage; P d Indicates the rated power of the drive system; P ac Indicates the rated power of the accessory system. The rated power consumption of the hydrogen fuel cell vehicle is the sum of the rated power of the drive system and the rated power of the accessory system; T on Indicates the estimated startup time, △T off Indicates the estimated shutdown duration.

[0014] Optionally, in the battery maintenance mode, the power limited SOC threshold SOC end According to the pre-acquired temperature of the power battery and the power limited SOC threshold SOC end The relationship curve is obtained.

[0015] Optionally, the hydrogen fuel cell vehicle has a hydrogen hybrid mode, and in the hydrogen hybrid mode, the SOC of the power battery varies with the mileage of the hydrogen fuel cell vehicle; In the hydrogen mixing mode: The SOC FCon The calculation formula is: ; In the formula, SOC end Indicates the power-limited SOC threshold of the power battery; Q b Indicates the power battery capacity; V oc Indicates the power battery voltage; P d Indicates the rated power of the drive system. P ac represents the rated power of the accessory system. The rated power consumption of the hydrogen fuel cell vehicle is the sum of the rated power of the drive system and the rated power of the accessory system; P s Indicates that when the power battery is working alone, the vehicle is moving at an average speed Driving can make SOC along SOC ref Changing power; SOC ref represents the reference value of SOC, the SOC ref Changes with the cumulative mileage of hydrogen fuel cell vehicles; △T on Indicates the estimated startup time; Among them, the SOC end The calculation method is: Calculate the estimated startup time △T on After that, the cumulative mileage of hydrogen fuel cell vehicles , The calculation formula is: ; Where: Indicates the average vehicle speed; represents the cumulative mileage of the vehicle at time t; Leveraging SOC ref Calculate the estimated startup time △T on The following power battery SOC lower limit SOC end : SOC ref The calculation formula is: ; In the formula, SOC ref (t) represents the reference value of SOC at time t; SOC st Indicates the initial SOC of the working condition; SOC f Indicates the minimum reference limit of SOC; D veh(t) represents the cumulative mileage of the vehicle at time t; D total Indicates the expected value of vehicle driving range; SOC end The calculation formula is: ; In the formula, express t+△T on Reference value of SOC at the moment; express t+△T on The accumulated mileage of the vehicle at the time; And, in the hydrogen mixing mode: The SOC FCoff The calculation formula is: ; In the formula, SOC end Indicates the power-limited SOC threshold of the power battery; Q b Indicates the power battery capacity; V oc Indicates the power battery voltage; P d Indicates the rated power of the drive system; P ac represents the rated power of the accessory system; the rated power consumption of the hydrogen fuel cell vehicle is the sum of the rated power of the drive system and the rated power of the accessory system; P s Indicates that when the power battery works alone, the vehicle speed Can make SOC along SOC ref Changing power; SOC ref represents the reference value of SOC, the SOC ref Variation with mileage; △T on Indicates the estimated startup time; △T off Indicates the estimated shutdown duration; Among them, the SOC end The calculation method is: Calculate the estimated value of the startup time △T on And the estimated shutdown time △T off Driving range of hydrogen fuel cell vehicles , The calculation formula is: ; Where: Indicates the average vehicle speed; represents the cumulative mileage of the vehicle at time t; Leveraging SOC ref Calculate the estimated startup time △T on And the estimated shutdown time △T offThe following power battery SOC lower limit SOC end : ; In the formula, SOC ref (t) represents the SOC reference value at time t; SOC st Indicates the initial SOC of the working condition; SOC f Indicates the minimum reference limit of SOC; D veh (t) represents the cumulative mileage of the vehicle at time t; D total Indicates the expected driving range of the vehicle; ; In the formula, Represents t+△T on +△T off The accumulated mileage of the vehicle at the moment; Represents t+△T on +△T off SOC reference value at the moment.

[0016] In a second aspect, the present invention provides a hydrogen fuel cell start-stop control device for a hydrogen fuel cell vehicle, comprising: An estimation module, used to determine an estimated startup duration and an estimated shutdown duration of the hydrogen fuel cell according to an ambient temperature of the hydrogen fuel cell vehicle and a temperature of the hydrogen fuel cell; A calculation module is used to calculate the power consumption of the hydrogen fuel cell vehicle and the estimated startup time when the SOC of the power battery drops to the power limit threshold SOC end The SOC threshold SOC that can complete the start-up of the hydrogen fuel cell FCon ; And according to the rated power consumption of the hydrogen fuel cell vehicle, the estimated startup time and the estimated shutdown time of the hydrogen fuel cell, calculate the power consumption when the SOC of the power battery drops to the power limit threshold SOC end The SOC threshold SOC at which a hydrogen fuel cell shutdown can be completed once and a hydrogen fuel cell startup can be completed again FCoff ; The response module is used for when the power battery is in the working state and the SOC of the power battery is in the SOC FCon and SOC FCoff In response to the SOC of the power battery dropping to the SOC FCon , starting the hydrogen fuel cell, and in response to the SOC of the power battery rising to the SOC FCoff , shut down the hydrogen fuel cell.

[0017] In a third aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements a hydrogen fuel cell start-stop control method for a hydrogen fuel cell vehicle as described in any one of claims 1-8.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. When the start-stop method provided by the present invention is applied to the existing energy management method of hydrogen fuel cell vehicles, it can reasonably determine the start-stop timing of the hydrogen fuel cell and on and threshold SOC off The setting can ensure that the hydrogen fuel cell has enough time to start before the SOC drops to the point where the power battery discharge power is limited, which can not only meet the power demand of the whole vehicle but also prevent the SOC from fluctuating greatly and causing frequent starts and stops, thereby delaying the life attenuation rate of the hydrogen fuel cell.

[0019] 2. The hydrogen fuel cell start-stop control method provided by the present invention can be directly applied to the existing energy management method of hydrogen fuel cell vehicles (such as the equivalent minimum hydrogen consumption control strategy ECMS), so that the energy management method takes the minimum total hydrogen consumption of economic factors as the control target, and at the same time, there is a limit standard for the start-stop control of the hydrogen fuel cell, thereby extending the life of the hydrogen fuel cell.

[0020] 3. When the hydrogen fuel cell start-stop control method provided by the present invention is applied to the existing energy management method of hydrogen fuel cell vehicles, it can also make the operation of hydrogen fuel cell vehicles under the entire energy management strategy more stable. Because the startup and shutdown time of hydrogen fuel cells are much longer than those of internal combustion engines, the existing energy management strategy lacks control standards for the start and stop of hydrogen fuel cells, resulting in the power battery working alone during the shutdown period of the hydrogen fuel cell. When the driver requests a large amount of power, the SOC of the power battery may quickly drop to the power limit threshold SOC end During this process, the hydrogen fuel cell cannot start quickly, causing the SOC of the power battery to drop to the power limiting threshold SOC. end After that, the driver's requested power is difficult to be met, which may directly affect the normal driving of the hydrogen fuel cell vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic flow chart of a method for starting and stopping a hydrogen fuel cell for a new energy vehicle provided in Example 1; Figure 2 A schematic diagram of the start-stop control of a hydrogen fuel cell when a start-stop control method for a hydrogen fuel cell for a new energy vehicle in Example 1 is applied to a power maintenance (CS) mode of a hydrogen fuel cell vehicle; Figure 3This is a schematic diagram of the start-stop control of a hydrogen fuel cell when a start-stop control method for a new energy vehicle hydrogen fuel cell in Example 1 is applied to a hydrogen blended mode (Blended) of a hydrogen fuel cell vehicle. DETAILED DESCRIPTION

[0022] 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.

[0023] 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

[0024] Combination Figure 1 This embodiment provides a method for starting and stopping a hydrogen fuel cell of a new energy vehicle. The driving system of the hydrogen fuel cell vehicle includes a hydrogen fuel cell and a power battery. The method includes: Step S1, obtaining an estimated startup duration and an estimated shutdown duration of the hydrogen fuel cell according to the ambient temperature of the hydrogen fuel cell vehicle and the temperature of the hydrogen fuel cell; Step S1 specifically includes: Determining a startup type and a shutdown type of the hydrogen fuel cell according to the ambient temperature of the hydrogen fuel vehicle and the temperature of the hydrogen fuel cell; Obtaining a startup duration estimation value and a shutdown duration estimation value according to a startup type and a shutdown type of the hydrogen fuel cell; The startup types include hot engine startup, cold engine startup and low temperature cold startup: When the hydrogen fuel cell system is already operating and in a high temperature state, the start type is determined to be a hot engine start.

[0025] The hydrogen fuel cell is started when it is not in operation. When the temperature of the hydrogen fuel cell is low, the start type is determined to be a cold start.

[0026] When the ambient temperature is lower than a preset threshold (eg, zero degrees Celsius), the start type is determined to be a low-temperature cold start.

[0027] When the hot engine is started, the calculation formula for the estimated startup time is: ; In the formula, △T on1 Indicates the estimated startup time when the hot engine is started; Ton1 Indicates the preset hot engine startup time; k on1 Indicates the preset heat engine startup time adjustment proportional factor; When starting a cold machine, the calculation formula for the estimated startup time is: ; In the formula, △T on2 Indicates the estimated startup time when the cold machine is started; T on2 Indicates the preset cold machine startup time; k on2 Indicates the preset cold machine startup time adjustment proportional factor; When starting at low temperature, the estimated start-up time is calculated as follows: ; In the formula, △T on3 Indicates the estimated time of low temperature cold start; T on3 Indicates the preset low temperature cooling machine startup time; k on3 Indicates the preset low-temperature refrigerator startup time adjustment proportional factor; The estimated startup time △T on The startup type determined corresponds to the ΔT on1 , △T on2 , △T on3 One of them; In this embodiment, the thermal engine startup time T on1 is 10 seconds, cold start time T on2 The low temperature cold start time is 15 seconds. on3 It is 480 seconds. For different application vehicles, the above specific data can be adjusted according to the actual situation. The proportional factor for adjusting the start-up time of the hot engine, the proportional factor for adjusting the start-up time of the cold engine, and the proportional factor for adjusting the start-up time of the low-temperature cold engine are all calibrated quantities, and are generally taken as a number greater than 1. Because the start-up time at different temperatures provided by hydrogen fuel cell manufacturers is generally inconsistent with the actual test results of the vehicle, and there may be interference from factors that have not been considered, it is necessary to calibrate each proportional factor to ensure that the estimated value of the start-up time is accurate.

[0028] Different start-up types correspond to different estimated start-up time values, which will directly affect the subsequent start-stop control. Therefore, the start-up type of the hydrogen fuel cell needs to be determined in advance.

[0029] The shutdown types include normal temperature shutdown and low temperature shutdown: When shutting down at normal temperature, the calculation formula for the estimated shutdown time is: ; In the formula, △T off1 Indicates the estimated shutdown time when shutting down at normal temperature; T off1 Indicates the preset normal temperature shutdown time; k off1 Indicates the preset normal temperature shutdown time adjustment proportional factor.

[0030] The calculation formula for the estimated shutdown time during low temperature shutdown is: ; In the formula, △T off2 Indicates the estimated shutdown time when the low temperature is turned off; T off2 Indicates the preset low temperature shutdown time; k off2 Indicates the preset low temperature shutdown time adjustment proportional factor; The shutdown time estimation value △T off The shutdown type determined corresponds to the ΔT on1 , △T on2 , △T on3 One of them.

[0031] In this embodiment, the normal temperature shutdown time is 180 seconds, and the low temperature shutdown time is 400 seconds. When applied to different vehicles, the data can be flexibly adjusted according to the application vehicle. The normal temperature shutdown time adjustment proportional factor and the low temperature shutdown time adjustment proportional factor are also calibrated quantities, generally taking a number greater than 1. Because the startup time at different temperatures provided by hydrogen fuel cell manufacturers is generally inconsistent with the actual vehicle test results, there may be interference from factors that have not been considered. Therefore, it is necessary to calibrate the normal temperature shutdown time adjustment proportional factor and the low temperature shutdown time adjustment proportional factor to ensure that the startup time estimate is accurate. Similarly, different shutdown types correspond to different shutdown time estimates, which will directly affect the subsequent start-stop control. Therefore, it is necessary to predetermine the shutdown type of the hydrogen fuel cell.

[0032] Step S2: Calculate the power consumption of the hydrogen fuel cell vehicle and the estimated startup time when the power battery SOC drops to the power limit threshold SOC end The SOC threshold SOC that can complete the start-up of the hydrogen fuel cell FCon ; And according to the rated power consumption of the hydrogen fuel cell vehicle, the estimated startup time and the estimated shutdown time of the hydrogen fuel cell, the power consumption of the hydrogen fuel cell vehicle is calculated when the SOC drops to the power limiting threshold SOC end The SOC threshold SOC at which a hydrogen fuel cell shutdown can be completed once and a hydrogen fuel cell startup can be completed again FCoff ; Among them, the power limit threshold SOC end It can be set according to the data provided by the manufacturer, or determined according to the actual calibration results.

[0033] Specifically, the start-stop strategy in this embodiment is to ensure that the power battery SOC does not drop to the power limit threshold SOC due to the start-stop of the hydrogen fuel cell. end Under the premise of reducing the start and stop frequency of hydrogen fuel cells, in order to extend the life of hydrogen fuel cells.

[0034] In step S2, the actual start-stop control method is different for different modes of the hydrogen fuel cell vehicle. The hydrogen fuel cell vehicle in this embodiment has a CS power maintenance mode and a hydrogen hybrid mode after the CD mode (pure electric mode) when the hydrogen fuel cell and the power battery work together.

[0035] In this embodiment, the hydrogen fuel cell vehicle is normally driven in the hydrogen hybrid mode. If the SOC decreases too fast and approaches the SOC end , the CS mode will be activated to maintain SOC stability.

[0036] Combination Figure 2 , the hydrogen fuel cell vehicle is in the power maintenance mode (power maintenance (Charging of Sustaing, CS) phase): The SOC of the power battery is controlled to fluctuate within the control range; the SOC of the power battery decreases with the power output of the power battery, and at the same time, the power battery will be charged by using the power generated by the hydrogen fuel cell that exceeds the preset power when it is actually working, as well as the energy such as braking recovery energy, so that the SOC of the power battery can be stabilized to fluctuate within the control range. In the battery maintenance mode, the power limited SOC threshold SOC end According to the pre-acquired temperature of the power battery and the power limited SOC threshold SOC end The relationship curve can be obtained directly by looking up the table.

[0037] To ensure SOC FCon is the actual threshold value under extreme conditions (power battery pure power consumption), SOC FCon In the calculation process, it is assumed that the hydrogen fuel cell does not charge the power battery during the startup process. At the same time, it is assumed that the power consumption of the hydrogen fuel cell vehicle reaches the rated power consumption, that is, the power of the drive system and the power of the accessory system both reach the rated power, and it is assumed that there is no braking energy recovery during the startup process of the current hydrogen fuel cell.

[0038] In this embodiment, the change of SOC is calculated by the ampere-hour integration method formula:

[0039] Where, I represents the power battery current; Q b Indicates the power of the power battery; V oc Indicates the power battery voltage; P d Indicates the rated power of the drive system; P ac Indicates the rated power of the accessory system; When the vehicle controller VCU is actually running, the integral part of formula (6) is converted into a discrete sum to obtain formula (8), and then the numerator and denominator of the summation term are both constants, which can be further converted into formula (9).

[0040] ; In the formula, SOC end Indicates the power-limited SOC threshold of the power battery; Q b Indicates the power battery capacity; V oc Indicates the power battery voltage; P d Indicates the rated power of the drive system; P ac Indicates the rated power of the accessory system; the rated power consumption of the hydrogen fuel cell vehicle is the sum of the rated power of the drive system and the rated power of the accessory system; △ T on Indicates the estimated startup time; Formula (9) is the final SOC FCon The calculation formula for .

[0041] Because the shutdown and startup of hydrogen fuel cells cannot be completed instantly, SOC FCoff It is necessary to ensure that when the hydrogen fuel cell is shut down and restarted, the SOC of the power battery is still greater than the SOC end , thereby ensuring the power of the entire vehicle.

[0042] Based on such requirements, this embodiment uses SOC FCoff In the calculation, it is assumed that the hydrogen fuel cell does not charge the power battery during the process from when the energy management strategy starts to request the hydrogen fuel cell to shut down to when the shutdown is completed. It is also assumed that the power battery power consumption in the pure electric mode is in the fastest rate of decline. The minimum limit SOC of the hydrogen fuel cell in the extreme case (the hydrogen fuel cell consumes power alone) is calculated. FCoff .SOC FCOff It can be calculated by the following formula (10).

[0043] The SOC FCoff The formula is: ; In the formula, SOC end Indicates the power-limited SOC threshold of the power battery; Q b Indicates the power battery capacity; Voc Indicates the power battery voltage; P d Indicates the rated power of the drive system; P acIndicates the rated power of the accessory system; the rated power consumption of the hydrogen fuel cell vehicle is the sum of the rated power of the drive system and the rated power of the accessory system; △ T on Indicates the estimated startup time, △T off Indicates the estimated shutdown duration.

[0044] Combination Figure 3 , the hydrogen fuel cell vehicle in the battery hydrogen hybrid mode (blended range-extended control mode): In hydrogen hybrid mode, affected by the control strategy, the SOC of the power battery is difficult to maintain within a control range, and the corresponding power battery SOC reference value SOC ref It is a straight line that decreases with the mileage. SOC in power maintenance mode ref In fact, it is a fixed value, and SOC fluctuates around this fixed value.

[0045] In hydrogen hybrid mode, the power battery SOC will be around SOC ref Floating and gradually reaching SOC FCoff To meet the shutdown conditions of hydrogen fuel cells or reach SOC FCon The hydrogen fuel cell startup conditions are met. Therefore, the hydrogen fuel cell will be started and shut down at certain time intervals during the driving of the hydrogen fuel cell vehicle.

[0046] In the hydrogen hybrid mode, the SOC of the power battery varies with the mileage of the hydrogen fuel cell vehicle.

[0047] The SOC FCon The calculation formula is: ; In the formula, SOC end Indicates the power-limited SOC threshold of the power battery; Q b Indicates the power battery capacity; Voc Indicates the power battery voltage; P d Indicates the rated power of the drive system; P ac represents the rated power of the accessory system; the rated power consumption of the hydrogen fuel cell vehicle is the sum of the rated power of the drive system and the rated power of the accessory system; P s Indicates that the vehicle is moving at an average speed when the power battery is working alone. Driving can make SOC along SOC ref Changing power; SOC ref represents the reference value of SOC, the SOC ref Varies with mileage; △T onIndicates the estimated startup time. end The calculation method is: Calculate the estimated startup time △T on Cumulative mileage of post-hydrogen fuel cell vehicles ,△ T on Average speed for mileage The estimated formula is: ; Where: Indicates the average vehicle speed; represents the cumulative mileage of the vehicle at time t; This embodiment uses SOC ref Calculate the estimated startup time △T on The following power battery SOC lower limit SOC end , Among them, the SOC reference value SOC varies with mileage ref The calculation formula is: ; In the formula, SOC ref (t) represents the SOC reference value at time t; SOC st Indicates the initial SOC of the working condition; SOC f Indicates the minimum reference limit of SOC; D veh (t) represents the cumulative mileage of the vehicle at time t; D total Indicates the expected value of vehicle driving range; ; In the formula, = t+△T on The vehicle's cumulative mileage at each moment.

[0048] And, in the hydrogen mixing mode: The SOC FCoff The calculation formula is: ; In the formula, SOC end Indicates the power-limited SOC threshold of the power battery; Q b Indicates the power battery capacity; V oc Indicates the power battery voltage; P d Indicates the rated power of the drive system. P ac represents the rated power of the accessory system. The rated power consumption of the hydrogen fuel cell vehicle is the sum of the rated power of the drive system and the rated power of the accessory system; P s Indicates that when the power battery works alone, the vehicle speed Can make SOC along SOC ref Changing power; SOC ref Indicates the reference value of SOC changing with mileage; △T on Indicates the estimated startup time; △T off Indicates the estimated shutdown duration; Among them, the SOC end The calculation method is: Calculate the estimated startup time △T on And the estimated shutdown time △T off Driving range of hydrogen fuel cell vehicles , △T on +△T off Average speed for mileage Make an estimate, The calculation formula is: ; Where: Indicates the average vehicle speed; represents the cumulative mileage of the vehicle at time t; Leveraging SOC ref Calculate the estimated startup time △T on And the estimated shutdown time △T off The following power battery SOC lower limit SOC end : ; In the formula, SOC ref (t) represents the SOC reference value at time t; SOC st Indicates the initial SOC of the working condition; SOC f Indicates the minimum reference limit of SOC; D veh (t) represents the cumulative mileage of the vehicle at time t; D total Indicates the expected driving range of the vehicle; ; In the formula, Represents t+△T on +△T off The cumulative mileage of the vehicle at the time.

[0049] In a specific embodiment, in formula (12) and formula (17), the weighted average driving power P of the mileage is used. ds Alternative driving power P d To calculate, the P ds The calculation formula is: ; In the formula, E1 represents the power consumption of the driving system corresponding to the time t1 of the driving distance S; E2 represents the power consumption of the driving system corresponding to the time t2 of the driving distance S; E3 represents the power consumption of the driving system corresponding to the time t3 of the driving distance S; E4 represents the power consumption of the driving system corresponding to the time t4 of the driving distance S; k1~k4 represent the mileage power weight coefficient, satisfying k1+k2+k3+k4 =1, here k1=0.1, k2=0.2, k3=0.4, k4=0.3. Driving distance S=5~10km.

[0050] Step S3: When the power battery is in working state and the SOC of the power battery is at SOC FCon and SOC FCoff In response to the SOC of the power battery dropping to the SOC FCon , starting the hydrogen fuel cell, and in response to the SOC of the power battery rising to the SOC FCoff , shut down the hydrogen fuel cell.

[0051] That is, only when the SOC of the power battery meets the threshold SOC FCon or threshold SOC FCoff When the conditions are met, the hydrogen fuel cell is started or shut down. When the SOC of the power battery is between two thresholds, the hydrogen fuel cell remains started, thereby effectively limiting the start and stop of the hydrogen fuel cell based on the reference value of SOC to extend the service life of the hydrogen fuel cell.

[0052] At the same time, this embodiment adjusts the threshold SOC FCon and threshold SOC FCoff The calculation ensures that even if the hydrogen fuel cell is shut down, the power battery SOC drops to the power limiting threshold SOC end Before the hydrogen fuel cell is started, the hydrogen fuel cell can also complete the startup in time to avoid the power limitation when the power battery works alone, thereby meeting the driver's power demand. During the startup and shutdown process of the hydrogen fuel cell, the driver's requested power is fully provided by the power battery.

[0053] In the power maintenance mode or in the hydrogen mixing mode, the threshold SOC in step S3 FCon and threshold SOC FCoff The calculation can be performed according to the corresponding calculation method in step S2.

[0054] In a preferred embodiment, in order to avoid frequent startup of the hydrogen fuel cell, before starting the hydrogen fuel cell, it is determined that when the power battery is working alone, the shutdown time ΔT of the hydrogen energy battery is FCoff Is it greater than or equal to the limit value T FCoff , If the judgment is yes, the hydrogen fuel cell is started; if the judgment is no, the hydrogen fuel cell is not started; Where T FCoff The calculation formula is: ; In the formula, k T1 Indicates the minimum downtime adjustment factor of the hydrogen fuel cell, 1.0≤k T1 ≤2, T off1 Indicates the pre-acquired normal temperature shutdown time.

[0055] If the SOC is reached when the vehicle is started end That is, it determines whether the power battery has the ability to start the hydrogen fuel cell. If it meets the requirements, the vehicle control uses the CAN network to request the hydrogen fuel cell controller FCU to start the hydrogen fuel cell.

[0056] At the same time, in order to avoid frequent shutdown of the hydrogen fuel cell; before shutting down the hydrogen fuel cell, it is determined that when the power battery and the hydrogen fuel cell work together, the working time of the hydrogen fuel cell △T FCon Is it greater than or equal to T? FCon , ; If the judgment is yes, the hydrogen energy battery is turned off; if the judgment is no, the hydrogen energy battery is not turned off; Where T FCon The calculation formula used is: ;k T2 Indicates the minimum operating time adjustment scale factor of the hydrogen fuel cell, 0.9≤k T2 ≤2; Indicates the sum of the pre-acquired hot machine startup time and normal temperature shutdown time.

[0057] Example 2 This embodiment provides an application example of the start-stop control method of a hydrogen fuel cell vehicle in Embodiment 1, which is specifically applied to an energy management method of a hydrogen fuel cell electric vehicle. The management method includes: Step Q1, calculating the driver's requested power according to the driver's control signal collected in real time by the vehicle controller VCU; The vehicle control system VCU collects 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 demand power (its value is unique at any time).

[0058] Step Q2: using the start-stop control method for a hydrogen fuel cell vehicle described in Example 1 to determine whether the hydrogen fuel cell needs to be started or shut down in the next control cycle. Step Q3: If it is determined that in the next control cycle, the hydrogen fuel cell is turned off or not started, and the driver's requested power of the hydrogen fuel cell vehicle is entirely provided by the power battery, the ECMS optimization algorithm controls with the power battery power equal to the driver's requested power as the control amount; or: The management method comprises: Step Q1, calculating the driver's requested power according to the driver's control signal collected in real time by the vehicle controller VCU; The vehicle control system VCU collects 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 demand power (its value is unique at any time).

[0059] Step Q2: using the start-stop control method for a hydrogen fuel cell vehicle described in Example 1 to determine whether the hydrogen fuel cell needs to be started or shut down in the next control cycle. Step Q3: If it is determined that in the next control cycle, the hydrogen fuel cell is started or not shut down, the driver's requested power of the hydrogen fuel cell vehicle is allocated to the power battery power and the hydrogen fuel cell power; Step Q4, selecting the lowest and highest limiting thresholds of the hydrogen fuel cell power and the highest limiting threshold of the hydrogen fuel cell power change rate according to the working state of the hydrogen fuel cell; Step Q5, estimating a feasible hydrogen fuel cell power sequence for the hydrogen fuel cell in the next control cycle according to the lowest and highest limit thresholds of the hydrogen fuel cell power and the highest limit threshold of the hydrogen fuel cell power change rate; Step Q6: subtract the hydrogen fuel cell power sequence from the driver's requested power to obtain a preliminary power battery power sequence for the next control cycle; and remove sequence points in the preliminary power battery power sequence that are outside the power range according to a predetermined feasible power range of the power battery power, so as to obtain a final power battery power sequence and a corresponding final hydrogen fuel cell power sequence; The method for determining the feasible power range of the power battery 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 by the power battery management system BMS in real time through the CAN network, thereby calculating the allowable real-time pulse discharge power limit, the allowable real-time pulse charging current power value, the allowable real-time continuous discharge power limit and the allowable real-time continuous charging power limit. The above-mentioned calculated limits are used as the feasible power range of the power battery in the hybrid state.

[0060] Step Q7, respectively calculating the equivalent hydrogen consumption at each power battery power in the power battery power sequence, and obtaining the equivalent hydrogen consumption sequence, respectively looking up the table to obtain the actual hydrogen consumption at each hydrogen fuel cell power in the hydrogen fuel cell power sequence, and obtaining the actual hydrogen consumption sequence; Step Q8: The equivalent hydrogen consumption sequence and the real hydrogen consumption sequence are added to form a total hydrogen consumption sequence. The ECMS optimization algorithm selects the hydrogen fuel cell power and the power battery power corresponding to the minimum hydrogen consumption in the total hydrogen consumption sequence as the control quantity for control.

[0061] The control strategy of minimum hydrogen consumption (ECMS) is the most commonly used strategy for power distribution of hydrogen fuel cell vehicles. Based on the above application examples, it can be determined that the start-stop control method in Example 1 can be directly applied to energy management methods and has broad practical application prospects.

[0062] Example 3 This embodiment provides a hydrogen fuel cell start-stop control device for a hydrogen fuel cell vehicle, comprising: An estimation module, used to determine an estimated startup duration and an estimated shutdown duration of the hydrogen fuel cell according to an ambient temperature of the hydrogen fuel cell vehicle and a temperature of the hydrogen fuel cell; The calculation module is used to calculate the power consumption of the hydrogen fuel cell vehicle and the estimated startup time when the power battery SOC drops to the power limit threshold SOC end The SOC threshold SOC that can complete the start-up of the hydrogen fuel cell FCon ; And according to the rated power consumption of the hydrogen fuel cell vehicle, the estimated startup time and the estimated shutdown time of the hydrogen fuel cell, the power consumption of the hydrogen fuel cell vehicle is calculated when the SOC drops to the power limiting threshold SOC end The SOC threshold SOC at which a hydrogen fuel cell shutdown can be completed once and a hydrogen fuel cell startup can be completed again FCoff ; The response module is used for when the power battery is in the working state and the SOC of the power battery is in the SOC FCon and SOC FCoff When: in response to the SOC of the power battery dropping to the SOC FCon , starting the hydrogen fuel cell, and in response to the SOC of the power battery rising to the SOC FCoff , shut down the hydrogen fuel cell.

[0063] Example 4 This embodiment provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the hydrogen fuel cell start-stop control method for a hydrogen fuel cell vehicle described in Embodiment 1 is implemented.

[0064] 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.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] 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 method for starting and stopping a hydrogen fuel cell of a hydrogen fuel cell vehicle, wherein the hydrogen fuel cell vehicle comprises a hydrogen fuel cell and a power battery; characterized in that: The method comprises: Determining an estimated startup duration and an estimated shutdown duration of the hydrogen fuel cell according to the ambient temperature of the hydrogen fuel cell vehicle and the temperature of the hydrogen fuel cell; According to the rated power consumption of the hydrogen fuel cell vehicle and the estimated startup time, the power consumption of the power battery is calculated to be reduced to the power limit threshold SOC end The SOC threshold SOC that can complete the start-up of the hydrogen fuel cell FCon ; According to the rated power consumption of the hydrogen fuel cell vehicle, the estimated startup time and the estimated shutdown time of the hydrogen fuel cell, the power consumption of the power battery is calculated to be reduced to the power limit threshold SOC end The SOC threshold SOC at which a hydrogen fuel cell shutdown can be completed once and a hydrogen fuel cell startup can be completed again FCoff ; When the power battery is in working state and the SOC of the power battery is at SOC FCon and SOC FCoff In between, In response to the SOC of the power battery decreasing to the SOC FCon , starting the hydrogen fuel cell, and In response to the SOC of the power battery rising to the SOC FCoff , shut down the hydrogen fuel cell.

2. The hydrogen fuel cell start-stop control method for a hydrogen fuel cell vehicle according to claim 1, characterized in that: The step of obtaining an estimated start-up time of the hydrogen fuel cell according to the ambient temperature of the hydrogen fuel cell vehicle and the temperature of the hydrogen fuel cell comprises: Determining the startup type of the hydrogen fuel cell according to the ambient temperature of the hydrogen fuel vehicle and the temperature of the hydrogen fuel cell; Obtaining an estimated startup duration of the hydrogen fuel cell according to a startup type of the hydrogen fuel cell; The startup types include hot engine startup, cold engine startup and low temperature cold startup: The calculation formula for the estimated startup time when the hot engine is started is: ; In the formula, △T on1 Indicates the estimated startup time when the hot engine is started; T on1 Indicates the preset hot engine startup time; k on1 Indicates the preset heat engine startup time adjustment proportional factor; The calculation formula for the estimated startup time when starting a cold machine is: ; In the formula, △T on2 Indicates the estimated startup time when the cold machine is started; T on2 Indicates the preset cold machine startup time; k on2 Indicates the preset cold machine startup time adjustment proportional factor; The calculation formula for the estimated startup time during low temperature cold start is: ; In the formula, △T on3 Indicates the estimated time of low temperature cold start; T on3 Indicates the preset low temperature cooling machine startup time; k on3 Indicates the preset low-temperature refrigerator startup time adjustment proportional factor; The estimated startup duration value corresponds to the ΔT according to the determined startup type. on1 , △T on2 , △T on3 One of them.

3. The hydrogen fuel cell start-stop control method for a hydrogen fuel cell vehicle according to claim 2, characterized in that: Obtaining an estimated shutdown duration of the hydrogen fuel cell according to the ambient temperature of the hydrogen fuel cell vehicle and the temperature of the hydrogen fuel cell includes: Determining a shutdown type of the hydrogen fuel cell according to the ambient temperature of the hydrogen fuel cell vehicle and the temperature of the hydrogen fuel cell; Obtaining an estimated shutdown duration of the hydrogen fuel cell according to a shutdown type of the hydrogen fuel cell; Wherein, the shutdown types include normal temperature shutdown and low temperature shutdown; The calculation formula for the estimated shutdown time when shutting down at normal temperature is: ; In the formula, △T off1 Indicates the estimated shutdown time when shutting down at normal temperature; T off1 Indicates the preset normal temperature shutdown time; k off1 Indicates the preset normal temperature shutdown time adjustment proportional factor; The calculation formula for the estimated shutdown time during low temperature shutdown is: ; In the formula, △T off2 Indicates the estimated shutdown time when the low temperature is turned off; T off2 Indicates the preset low temperature shutdown time; k off2 Indicates the preset low temperature shutdown time adjustment proportional factor; The shutdown duration estimation value corresponds to the ΔT according to the shutdown type determined. off1 , △T off2 One of them.

4. The hydrogen fuel cell start-stop control method for a hydrogen fuel cell vehicle according to claim 1, characterized in that: In response to the SOC of the power battery decreasing to the SOC FCon Before starting the hydrogen fuel cell, determine the shutdown time △T of the hydrogen fuel cell when the power battery is working alone. FCoff Is it greater than or equal to the limit value T FCoff , ; If the judgment is yes, the hydrogen energy battery is started; if the judgment is no, the hydrogen energy battery is not started; Where T FCoff The calculation formula is: ; In the formula, k T1 Indicates the preset minimum downtime adjustment factor of the hydrogen fuel cell, 1.0≤ k T1 ≤2, T off1 Indicates the pre-acquired normal temperature shutdown time.

5. The hydrogen fuel cell start-stop control method for a hydrogen fuel cell vehicle according to claim 1, characterized in that: In response to the SOC of the power battery rising to the SOC FCoff Before shutting down the hydrogen fuel cell, it is determined that when the power battery and the hydrogen fuel cell work together, the working time △T of the hydrogen fuel cell FCon Is it greater than or equal to T? FCon , ; If the judgment is yes, the hydrogen energy battery is turned off; if the judgment is no, the hydrogen energy battery is not turned off; Where T FCon The calculation formula used is: ;k T2 Indicates the preset minimum operating time adjustment scale factor of the hydrogen fuel cell, 0.9≤k T2 ≤2; Indicates the sum of the pre-acquired hot machine startup time and normal temperature shutdown time.

6. The hydrogen fuel cell start-stop control method for a hydrogen fuel cell vehicle according to claim 1, characterized in that: The hydrogen fuel cell vehicle has a battery maintenance mode, in which the SOC of the power battery is controlled to fluctuate within a control range. In the battery maintenance mode: The SOC FCon The calculation formula is: ; In the formula, SOC end Indicates the power-limited SOC threshold of the power battery; Q b Indicates the power battery capacity; V oc Indicates the power battery voltage; P d Indicates the rated power of the drive system. P ac Indicates the rated power of the accessory system. The rated power consumption of the hydrogen fuel cell vehicle is the sum of the rated power of the drive system and the rated power of the accessory system; T on Indicates the estimated startup time; The SOC FCoff The calculation formula is: ; In the formula, SOC end Indicates the power-limited SOC threshold of the power battery; Q b Indicates the power battery capacity; V oc Indicates the power battery voltage; P d Indicates the rated power of the drive system; P ac Indicates the rated power of the accessory system. The rated power consumption of the hydrogen fuel cell vehicle is the sum of the rated power of the drive system and the rated power of the accessory system; T on Indicates the estimated startup time, △T off Indicates the estimated shutdown duration.

7. The hydrogen fuel cell start-stop control method for a hydrogen fuel cell vehicle according to claim 6, characterized in that: In the battery maintenance mode, the power limited SOC threshold SOC end According to the pre-acquired temperature of the power battery and the power limited SOC threshold SOC end The relationship curve is obtained.

8. The hydrogen fuel cell start-stop control method for a hydrogen fuel cell vehicle according to claim 1, characterized in that: The hydrogen fuel cell vehicle has a hydrogen hybrid mode, and in the hydrogen hybrid mode, the SOC of the power battery varies with the mileage of the hydrogen fuel cell vehicle; In the hydrogen mixing mode: The SOC FCon The calculation formula is: ; In the formula, SOC end Indicates the power-limited SOC threshold of the power battery; Q b Indicates the power battery capacity; V oc Indicates the power battery voltage; P d Indicates the rated power of the drive system. P ac represents the rated power of the accessory system. The rated power consumption of the hydrogen fuel cell vehicle is the sum of the rated power of the drive system and the rated power of the accessory system; P s Indicates that when the power battery is working alone, the vehicle is moving at an average speed Driving can make SOC along SOC ref Changing power; SOC ref represents the reference value of SOC, the SOC ref Changes with the cumulative mileage of hydrogen fuel cell vehicles; △T on Indicates the estimated startup time; Among them, the SOC end The calculation method is: Calculate the estimated startup time △T on After that, the cumulative mileage of hydrogen fuel cell vehicles , The calculation formula is: ; Where: Indicates the average vehicle speed; represents the cumulative mileage of the vehicle at time t; Leveraging SOC ref Calculate the estimated startup time △T on The following power battery SOC lower limit SOC end : SOC ref The calculation formula is: ； In the formula, SOC ref (t) represents the reference value of SOC at time t; SOC st Indicates the initial SOC of the working condition; SOC f Indicates the minimum reference limit of SOC; D veh (t) represents the cumulative mileage of the vehicle at time t; D total Indicates the expected value of vehicle driving range; SOC end The calculation formula is: ; In the formula, express t+△T on Reference value of SOC at the moment; express t+△T on The accumulated mileage of the vehicle at the time; And, in the hydrogen mixing mode: The SOC FCoff The calculation formula is: ; In the formula, SOC end Indicates the power-limited SOC threshold of the power battery; Q b Indicates the power battery capacity; V oc Indicates the power battery voltage; P d Indicates the rated power of the drive system; P ac represents the rated power of the accessory system; the rated power consumption of the hydrogen fuel cell vehicle is the sum of the rated power of the drive system and the rated power of the accessory system; P s Indicates that when the power battery works alone, the vehicle speed Can make SOC along SOC ref Changing power; SOC ref represents the reference value of SOC, the SOC ref Variation with mileage; △T on Indicates the estimated startup time; △T off Indicates the estimated shutdown duration; Among them, the SOC end The calculation method is: Calculate the estimated value of the startup time △T on And the estimated shutdown time △T off Driving range of hydrogen fuel cell vehicles , The calculation formula is: ; Where: Indicates the average vehicle speed; represents the cumulative mileage of the vehicle at time t; Leveraging SOC ref Calculate the estimated startup time △T on And the estimated shutdown time △T off The following power battery SOC lower limit SOC end : ; In the formula, SOC ref (t) represents the SOC reference value at time t; SOC st Indicates the initial SOC of the working condition; SOC f Indicates the minimum reference limit of SOC; D veh (t) represents the cumulative mileage of the vehicle at time t; D total Indicates the expected driving range of the vehicle; ; In the formula, Represents t+△T on +△T off The accumulated mileage of the vehicle at the moment; Represents t+△T on +△T off SOC reference value at the moment.

9. A hydrogen fuel cell start-stop control device for a hydrogen fuel cell vehicle, characterized in that: include: An estimation module, used to determine an estimated startup duration and an estimated shutdown duration of the hydrogen fuel cell according to an ambient temperature of the hydrogen fuel cell vehicle and a temperature of the hydrogen fuel cell; A calculation module is used to calculate the power consumption of the hydrogen fuel cell vehicle and the estimated startup time when the SOC of the power battery drops to the power limit threshold SOC end The SOC threshold SOC that can complete the start-up of the hydrogen fuel cell FCon ; And according to the rated power consumption of the hydrogen fuel cell vehicle, the estimated startup time and the estimated shutdown time of the hydrogen fuel cell, calculate the power consumption when the SOC of the power battery drops to the power limit threshold SOC end The SOC threshold SOC at which a hydrogen fuel cell shutdown can be completed once and a hydrogen fuel cell startup can be completed again FCoff ; The response module is used for when the power battery is in the working state and the SOC of the power battery is in the SOC FCon and SOC FCoff In response to the SOC of the power battery dropping to the SOC FCon , starting the hydrogen fuel cell, and in response to the SOC of the power battery rising to the SOC FCoff , shut down the hydrogen fuel cell.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, a hydrogen fuel cell start-stop control method for a hydrogen fuel cell vehicle as described in any one of claims 1-8 is implemented.

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