Control Method and Device for a Fuel Cell System

Abstract

The present invention relates to the technical field of fuel cell vehicles, and particularly to a control method for a fuel cell system. The method includes: after the fuel cell system of the vehicle is started, obtaining the coolant inlet temperature of the fuel cell system; if the coolant inlet temperature is not less than the insulation temperature threshold, controlling the fuel cell system to enter the insulation mode; in the insulation mode, controlling the small circulation loop of the fuel cell system to be in a closed state and the large circulation loop to be in an open state, and in the large circulation loop, determining the actual pump speed of the water pump and the actual fan speed of the fan of the fuel cell system according to the required power of the fuel cell system. The method regulates the fuel cell system according to the power demand and temperature demand of the fuel cell system, ensures the stability of the fuel cell system when the power of the fuel cell system fluctuates, and avoids unnecessary energy waste.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cell vehicles, and particularly to a control method and device for a fuel cell system. Background Art

[0002] With the popularization and promotion of new energy hydrogen, more and more hydrogen fuel cell systems are applied to new energy vehicles, which are called fuel cell vehicles. In a fuel cell vehicle, it is necessary to accurately control the fuel cell vehicle so that the fuel cell vehicle can travel efficiently.

[0003] Currently, the control method of the fuel cell system is regulated based on the inlet temperature and outlet temperature of the fuel cell stack of the fuel cell system. In the existing control method, when the power of the fuel cell system fluctuates, the problem of low stability of the fuel cell system is caused. Summary of the Invention

[0004] By providing a control method and device for a fuel cell system in an embodiment of the present application, the technical problem of low stability of the fuel cell system when the power of the fuel cell system fluctuates in the prior art is solved, and the technical effects of regulating the fuel cell system according to the power demand and temperature demand of the fuel cell system, ensuring the stability of the fuel cell system when the power of the fuel cell system fluctuates, and avoiding unnecessary energy waste are achieved.

[0005] In a first aspect, an embodiment of the present invention provides a control method for a fuel cell system, including:

[0006] After the fuel cell system of the vehicle is started, obtain the coolant inlet temperature of the fuel cell system;

[0007] If the coolant inlet temperature is not less than the heat preservation temperature threshold, control the fuel cell system to enter the heat preservation mode;

[0008] In the heat preservation mode, control the small circulation loop of the fuel cell system to be in a closed state and the large circulation loop to be in an open state, and in the large circulation loop, determine the actual pump speed of the pump and the actual fan speed of the fan of the fuel cell system according to the required power of the fuel cell system.

[0009] Preferably, the determining the actual pump speed of the pump of the fuel cell system according to the required power of the fuel cell system in the large circulation loop includes:

[0010] According to the required power, obtain the set pump speed of the pump and the target temperature difference between the inlet and outlet of the fuel cell system;

[0011] Obtain the correction amount of the water pump speed of the water pump according to the target temperature difference between the inlet and outlet of the stack;

[0012] Obtain the actual water pump speed according to the set water pump speed and the correction amount of the water pump speed.

[0013] Preferably, in the large circulation loop, determining the actual fan speed of the fan of the fuel cell system according to the required power of the fuel cell system includes:

[0014] Obtain the set fan speed of the fan and the target outlet temperature of the fuel cell system according to the required power;

[0015] Obtain the correction amount of the fan speed according to the target outlet temperature;

[0016] Obtain the actual fan speed according to the set fan speed and the correction amount of the fan speed.

[0017] Preferably, in the heat preservation mode, it further includes:

[0018] If it is detected that the coolant inlet temperature of the stack is not greater than the temperature rise threshold, control the fuel cell system to switch from the heat preservation mode to the temperature rise mode, where the temperature rise threshold is less than the heat preservation temperature threshold;

[0019] In the temperature rise mode, control the small circulation loop to be in an open state and the large circulation loop to be in a closed state.

[0020] Preferably, in the process of controlling the small circulation loop to be in an open state, it further includes:

[0021] Determine the actual water pump speed according to the required power.

[0022] Preferably, after determining the actual water pump speed, it further includes:

[0023] Obtain the current water pump speed of the water pump;

[0024] If the current water pump speed is not less than the water pump speed threshold, within the first preset duration, control the fuel cell system to operate at the first actual power;

[0025] After controlling the fuel cell system to operate at the first actual power within the first preset duration, obtain the current temperature difference between the inlet and outlet of the stack of the fuel cell system;

[0026] If the current temperature difference between the inlet and outlet of the stack is not greater than the temperature difference threshold, output the alarm information of the water pump and shut down the fuel cell system.

[0027] Preferably, after determining the actual fan speed, the method further includes:

[0028] Obtaining the current fan speed of the fan;

[0029] If the current fan speed is not less than the fan speed threshold, within a second preset duration, controlling the fuel cell system to operate at a second actual power;

[0030] After controlling the fuel cell system to operate at the second actual power within the second preset duration, obtaining the temperature difference between the inlet and outlet of the radiator of the fuel cell system;

[0031] If the temperature difference between the inlet and outlet of the radiator is not greater than the radiator temperature difference threshold, outputting an alarm message of the fan and controlling the operating power of the fuel cell system to be within a restricted operating power range.

[0032] Preferably, after obtaining the coolant inlet temperature of the fuel cell system, the method further includes:

[0033] If the coolant inlet temperature is less than the heat preservation temperature threshold, controlling the fuel cell system to enter the heating mode;

[0034] In the heating mode, if it is detected that the coolant inlet temperature is not less than the heat preservation temperature threshold, controlling the fuel cell system to switch from the heating mode to the heat preservation mode.

[0035] Based on the same inventive concept, in a second aspect, the present invention further provides a control device for a fuel cell system, including:

[0036] An obtaining module, configured to obtain the coolant inlet temperature of the fuel cell system after the fuel cell system of the vehicle is started;

[0037] A judging module, configured to control the fuel cell system to enter the heat preservation mode if the coolant inlet temperature is not less than the heat preservation temperature threshold;

[0038] A control module, configured to, in the heat preservation mode, control the small circulation loop of the fuel cell system to be in a closed state and the large circulation loop to be in an open state, and in the large circulation loop, determine the actual water pump speed of the water pump of the fuel cell system and the actual fan speed of the fan according to the required power of the fuel cell system.

[0039] Based on the same inventive concept, in a third aspect, the present invention provides a fuel cell vehicle, including a memory, a processor, and a computer program stored on the memory and executable on the processor, and when the processor executes the program, the steps of the control method of the fuel cell system are implemented.

[0040] One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:

[0041] In the embodiments of the present invention, after the fuel cell system of the vehicle is started, first obtain the coolant inlet temperature of the fuel cell system. Then judge the coolant inlet temperature to determine whether the fuel cell system enters the heat preservation mode. If the coolant inlet temperature is not less than the heat preservation temperature threshold, control the fuel cell system to enter the heat preservation mode.

[0042] In the heat preservation mode, control the small circulation loop of the fuel cell system to be in a closed state and the large circulation loop to be in an open state, and in the large circulation loop, determine the actual pump speed of the water pump and the actual fan speed of the fan of the fuel cell system according to the required power of the fuel cell system. Here, according to the power demand of the fuel cell system, adjust the fuel cell system. When the power of the fuel cell system fluctuates, ensure the stability of the fuel cell system, avoid unnecessary energy waste, and achieve precise control of the fuel cell system. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] By reading the following detailed description of the preferred embodiments, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered to be a limitation of the present invention. And throughout the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0044] Figure 1 Shows the schematic flow chart of the steps of the control method of the fuel cell system in the embodiments of the present invention;

[0045] Figure 2 Shows the schematic structural diagram of the fuel cell system in the embodiments of the present invention;

[0046] Figure 3 Shows the schematic flow chart of switching the heating-up mode and the heat preservation mode of the control method of the fuel cell system in the embodiments of the present invention;

[0047] Figure 4 Shows another schematic flow chart of the steps of the control method of the fuel cell system in the embodiments of the present invention;

[0048] Figure 5 Shows the schematic flow chart of detecting the water pump in the embodiments of the present invention;

[0049] Figure 6 Shows the schematic flow chart of detecting the fan in the embodiments of the present invention;

[0050] Figure 7 Shows the schematic module diagram of the control device of the fuel cell system in the embodiments of the present invention. Specific Embodiments

[0051] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be fully conveyed to those skilled in the art.

[0052] Embodiment 1

[0053] The first embodiment of the present invention provides a control method for a fuel cell system, as Figure 1 shown, including:

[0054] S101, after the fuel cell system of the vehicle is started, obtain the coolant inlet temperature of the fuel cell system;

[0055] S102, if the coolant inlet temperature is not less than the heat preservation temperature threshold, control the fuel cell system to enter the heat preservation mode;

[0056] S103, in the heat preservation mode, control the small circulation loop of the fuel cell system to be in a closed state and the large circulation loop to be in an open state, and in the large circulation loop, determine the actual pump speed of the water pump and the actual fan speed of the fan of the fuel cell system according to the required power of the fuel cell system.

[0057] The control method of the fuel cell system in this embodiment is applied to the fuel cell system, specifically applied to the fuel cell controller FCCU (Fuel cell control unit) of the fuel cell system.

[0058] As Figure 2 shown, the fuel cell system includes: a fuel cell controller FCCU, a fuel cell stack (the fuel cell stack is a fuel cell FCS, Fuel Cell Stack, FCS), a temperature control valve, a PTC heater, a water pump, a filter, a radiator, a fan, a boost DCDC (Direct Current, direct current converter), a coolant inlet temperature sensor Tin, a coolant outlet temperature sensor Tout, a radiator outlet temperature sensor Tfan, a radiator inlet temperature sensor Tfou, and a coolant inlet pressure sensor Pin.

[0059] Channel 1 of the temperature control valve is connected to the outlet of the battery stack, channel 2 of the temperature control valve is connected to one end of the PTC heater, and channel 3 of the temperature control valve is connected to the inlet of the radiator. The outlet of the radiator and the other end of the PTC heater are both connected to the inlet of the filter, and the outlet of the filter is connected to the inlet of the battery stack. The fan is arranged near the radiator to dissipate heat for the radiator. The coolant inlet pressure sensor Pin and the coolant inlet temperature sensor Tin are both arranged at the inlet of the battery stack. The coolant outlet temperature sensor Tout is arranged at the outlet of the battery stack. The radiator outlet temperature sensor Tfan is arranged at the outlet of the radiator, and the radiator inlet temperature sensor Tfou is arranged at the inlet of the radiator.

[0060] The coolant inlet pressure sensor Pin, coolant inlet temperature sensor Tin, coolant outlet temperature sensor Tout, radiator outlet temperature sensor Tfan, radiator inlet temperature sensor Tfou, temperature control valve, water pump, PTC heater and fan are all connected to the fuel cell controller FCCU. The positive and negative electrodes of the stack are connected to the boost DCDC, which is also connected to the vehicle load. The boost DCDC is used to transmit the electric energy generated by the stack to the vehicle load.

[0061] The temperature control valve is used to switch the small circulation loop and the large circulation loop of the coolant in the fuel cell system. Specifically, the switching of the small circulation loop and the large circulation loop is realized by the opening of the temperature control valve. When the channels 1 and 2 of the temperature control valve are turned on and the channel 3 is closed, the coolant flows through the outlet of the stack, the channel 1 of the temperature control valve, the channel 2 of the temperature control valve, the PTC heater, the water pump, the filter and the inlet of the stack in turn to form a small circulation loop of the coolant. When the channels 1 and 3 of the temperature control valve are turned on and the channel 2 is closed, the coolant flows through the outlet of the stack, the channel 1 of the temperature control valve, the channel 3 of the temperature control valve, the radiator, the water pump, the filter and the inlet of the stack in turn to form a large circulation loop of the coolant. The PTC heater is used to heat the coolant in the small circulation loop. The radiator is used to dissipate heat from the coolant in the large circulation loop. The water pump is used to control the flow of the coolant.

[0062] Next, combine Figures 1 to 4 The specific implementation steps of the control method of the fuel cell system provided in this embodiment are described in detail:

[0063] It should be noted that Figure 3 It is a schematic diagram of switching the temperature rise mode and the temperature keeping mode of the control method of the fuel cell system of this embodiment. Figure 4 FIG. 4 is another flow chart of the steps of the control method of the fuel cell system of the present embodiment.

[0064] First, step S101 is executed to obtain the coolant inlet temperature of the fuel cell system after the fuel cell system of the vehicle is started.

[0065] Specifically, after the fuel cell system of the vehicle is started, the coolant inlet temperature to the stack is measured by the coolant inlet temperature sensor Tin to the stack. Herein, the coolant inlet temperature to the stack is the temperature when the coolant enters the fuel cell stack.

[0066] After obtaining the coolant inlet temperature to the stack, it is necessary to judge the coolant inlet temperature to the stack to determine whether the fuel cell system enters the heating mode or the heat preservation mode. The heating mode is a mode in which the coolant is heated by the PTC heater during the process of the coolant circulating in the small circulation loop. For example, when the vehicle is cold-started, it is necessary to heat and raise the temperature of the coolant by the PTC heater so that the coolant can circulate normally in the fuel cell system. The heat preservation mode is a mode in which the coolant circulates in the large circulation loop.

[0067] Then, step S102 is executed. If the coolant inlet temperature to the stack is not less than the heat preservation temperature threshold, the fuel cell system is controlled to enter the heat preservation mode.

[0068] Specifically, as Figure 3 shown, if the coolant inlet temperature to the stack is not less than the heat preservation temperature threshold, the fuel cell system is controlled to enter the heat preservation mode. Herein, the heat preservation temperature threshold is the minimum value of the coolant inlet temperature to the stack when the fuel cell system enters the heat preservation mode. The heat preservation temperature threshold is set according to actual requirements. Usually, the heat preservation temperature threshold is set to 50 °C.

[0069] In the heat preservation mode, if it is detected that the coolant inlet temperature to the stack is not greater than the heating temperature threshold, the fuel cell system is controlled to switch from the heat preservation mode to the heating mode, wherein the heating temperature threshold is less than the heat preservation temperature threshold. The heating temperature threshold is set according to actual requirements. Usually, the heating temperature threshold is set to 48 °C. If it is detected that the coolant inlet temperature to the stack is greater than the heating temperature threshold, the fuel cell system is controlled to remain in the heat preservation mode.

[0070] In this embodiment, by setting the heating temperature threshold and the heat preservation temperature threshold, the fuel cell system can quickly perform mode switching and accurately enter the heating mode or the heat preservation mode, avoiding the situation that the fuel cell system repeatedly and frequently switches between the heating mode and the heat preservation mode due to setting only one temperature threshold, and improving the stability and reliability of the fuel cell system.

[0071] If the coolant inlet temperature to the stack is less than the heat preservation temperature threshold, the fuel cell system is controlled to enter the heating mode. In the heating mode, if it is detected that the coolant inlet temperature to the stack is not less than the heat preservation temperature threshold, the fuel cell system is controlled to switch from the heating mode to the heat preservation mode. If it is detected that the coolant inlet temperature to the stack is less than the heat preservation temperature threshold, the fuel cell system is controlled to remain in the heating mode so that the PTC heater heats the coolant and the coolant temperature rises.

[0072] As Figure 4 shown, in the heating mode, the small circulation loop is controlled to be in the open state, and the large circulation loop is controlled to be in the closed state. Among them, the open state is the state in which the device or loop operates, and the closed state is the state in which the operation of the device or loop is prohibited.

[0073] Specifically, in the heating mode, since the small circulation loop is in the open state and the large circulation loop is in the closed state, in the small circulation loop, the water pump is controlled to start running at the lowest speed, and in the large circulation loop, the fan is controlled to be in the closed state.

[0074] During the process of controlling the small circulation loop to be in the open state, according to the required power of the fuel cell system, the actual water pump speed of the water pump is determined. Among them, the required power is the power required to ensure the operation of the fuel cell system. In the specific implementation process, there is a pre-calibrated required power - water pump speed table of the fuel cell system in the fuel cell system. According to the required power of the fuel cell system, query this table to determine the actual water pump speed of the water pump. And control the water pump to run at the actual water pump speed.

[0075] Then, step S103 is executed. In the heat preservation mode, the small circulation loop of the fuel cell system is controlled to be in the closed state and the large circulation loop is in the open state, and in the large circulation loop, according to the required power of the fuel cell system, the actual water pump speed of the water pump of the fuel cell system and the actual fan speed of the fan are determined.

[0076] Specifically, in the heat preservation mode, the small circulation loop is controlled to be in the closed state, and the large circulation loop is also controlled to be in the open state. In the heat preservation mode, since the small circulation loop is in the closed state and the large circulation loop is in the open state, the PTC heater is controlled to be in the closed state and the fan is in the open state.

[0077] In the large circulation loop, according to the required power of the fuel cell system, the actual water pump speed of the water pump of the fuel cell system is determined. Specifically:

[0078] a. According to the required power, the set water pump speed of the water pump and the target temperature difference between the inlet and outlet of the fuel cell system are obtained.

[0079] In the specific implementation process, according to the required power of the fuel cell system, query the required power - water pump speed table of the fuel cell system to obtain the set water pump speed Nwp_ff of the water pump. Among them, the set water pump speed is the water pump speed corresponding to the required power of the fuel cell system in the required power - water pump speed table of the fuel cell system.

[0080] According to the required power of the fuel cell system, query the fuel cell system - in - out stack temperature difference table to obtain the target in - out stack temperature difference T11. The target in - out stack temperature difference is the in - out stack temperature difference corresponding to the required power of the fuel cell system in the fuel cell system - in - out stack temperature difference table. The in - out stack temperature difference represents the difference between the coolant inlet temperature to the stack and the coolant outlet temperature from the stack. The fuel cell system - in - out stack temperature difference table is pre - stored in the fuel cell system.

[0081] b. Obtain the pump speed correction amount of the water pump according to the target in - out stack temperature difference.

[0082] In the specific implementation process, in the process of obtaining the target in - out stack temperature difference, first obtain the current coolant inlet temperature to the stack and the current coolant outlet temperature from the stack, and then subtract the current coolant outlet temperature from the current coolant inlet temperature to the stack to obtain the current in - out stack temperature difference T12.

[0083] In the process of performing PID closed - loop control on the speed of the water pump, according to the difference between the target in - out stack temperature difference T11 and the current in - out stack temperature difference T12, and the preset water pump speed adjustment coefficient Nwp_PI of the water pump, obtain the water pump speed correction amount Nwp_eff. Among them, the preset water pump speed adjustment system Nwp_PI is obtained in the process of actual calibration and debugging of the speed of the water pump and is pre - stored in the fuel cell system.

[0084] c. Obtain the actual water pump speed according to the set water pump speed and the water pump speed correction amount.

[0085] In the specific implementation process, the actual water pump speed Nwp = the set water pump speed Nwp_ff+the water pump speed correction amount Nwp_eff, where the actual water pump speed Nwp≥the minimum speed of the water pump.

[0086] In this embodiment, according to the required power of the fuel cell system and the in - out stack temperature difference of the coolant, the water pump of the fuel cell system is regulated to improve the stability and reliability of the water pump during operation, and then improve the stability and reliability of the fuel cell system during operation, saving energy.

[0087] In the large - circulation loop, according to the required power of the fuel cell system, determine the actual fan speed of the fan of the fuel cell system, specifically:

[0088] a. Obtain the set fan speed of the fan and the target outlet temperature of the fuel cell system according to the required power.

[0089] In the specific implementation process, according to the required power of the fuel cell system, query the required power - fan speed table of the fuel cell system to obtain the set fan speed Nfan_ff of the fan. Among them, the set fan speed is the fan speed corresponding to the required power of the fuel cell system in the required power - fan speed table of the fuel cell system.

[0090] According to the required power of the fuel cell system, query the fuel cell system - outlet temperature table to obtain the target outlet temperature T21. The target outlet temperature is the outlet temperature corresponding to the required power of the fuel cell system in the fuel cell system - outlet temperature table, and the outlet temperature represents the coolant outlet temperature. The fuel cell system - outlet temperature table is pre - stored in the fuel cell system.

[0091] b. Obtain the fan speed correction amount of the fan according to the target outlet temperature.

[0092] In the specific implementation process, during the process of obtaining the target outlet temperature, obtain the current coolant outlet temperature, that is, obtain the current outlet temperature T22. During the process of performing PID closed - loop control on the fan speed, according to the difference between the target outlet temperature T21 and the current outlet temperature T22, and the preset fan speed adjustment coefficient Nfan_PI of the fan, obtain the fan speed correction amount Nfan_eff. Among them, the preset fan speed adjustment system Nfan_PI is obtained during the actual calibration and debugging of the fan speed and is pre - stored in the fuel cell system.

[0093] c. Then, obtain the actual fan speed according to the set fan speed and the fan speed correction amount.

[0094] In the specific implementation process, the actual fan speed Nfan = set fan speed Nfan_ff+fan speed correction amount Nfan_eff, where Nfan≥0.

[0095] In this embodiment, according to the required power of the fuel cell system and the outlet temperature of the coolant, the fan of the fuel cell system is regulated to improve the stability and reliability of the fan during operation, and then improve the stability and reliability of the fuel cell system during operation, saving energy.

[0096] Whether in the small - circulation loop or in the large - circulation loop, after determining the actual pump speed of the water pump, first obtain the current pump speed of the water pump. Then judge the current pump speed, as Figure 5 shown. If the current pump speed is not less than the pump speed threshold, within the first preset time period, control the fuel cell system to operate at the first actual power. If the current pump speed is less than the pump speed threshold, continue to detect the current pump speed of the water pump.

[0097] In this embodiment, the water pump speed threshold is the minimum speed of the water pump, and its specific value is set according to actual requirements. The first actual power is the actual operating power of the fuel cell system within the first preset time period, and the first actual power is not less than the idle power of the fuel cell system. The first preset time period and the first actual power are set according to actual requirements, and the first actual power is usually set to 5KW.

[0098] After controlling the fuel cell system to operate at the first actual power within the first preset time period, obtain the current in-and-out stack temperature difference of the fuel cell system, where the current in-and-out stack temperature difference is the difference between the current coolant inlet stack temperature and the current coolant outlet stack temperature. If the current in-and-out stack temperature difference is not greater than the temperature difference threshold, indicating that the water pump is malfunctioning, then output the alarm information of the water pump and shut down the fuel cell system. If the current in-and-out stack temperature difference is greater than the temperature difference threshold, indicating that the water pump is operating normally, then output the information that the water pump is operating normally.

[0099] It should be noted that the temperature difference threshold is set according to actual requirements, and the temperature difference threshold is usually set to 3°C.

[0100] This embodiment can intelligently detect the working state of the water pump. When there is an abnormality in the water pump, it can timely detect the fault of the water pump, send out the alarm information of the water pump, control the shutdown of the fuel cell system, ensure that the fuel cell system will not be irreversibly damaged due to abnormal temperature, improve the stability and reliability of the fuel cell system, and achieve precise control of the fuel cell system.

[0101] In the large circulation loop, after determining the actual fan speed, first obtain the current fan speed of the fan. Then judge the current fan speed, as Figure 6 shown. If the current fan speed is not less than the fan speed threshold, then within the second preset time period, control the fuel cell system to operate at the second actual power. If the current fan speed is less than the fan speed threshold, then continue to detect the current fan speed of the fan.

[0102] In this embodiment, the fan speed threshold is the minimum speed of the fan, and its specific value is set according to actual requirements. The second actual power is the actual operating power of the fuel cell system within the second preset time period. The second preset time period and the second actual power are set according to actual requirements, and the second actual power is usually set to 20KW.

[0103] After controlling the fuel cell system to operate at a second actual power within a second preset duration, obtain the temperature difference between the inlet and outlet of the radiator of the fuel cell system, where the temperature difference between the inlet and outlet of the radiator is the difference between the radiator inlet temperature and the radiator outlet temperature, the radiator inlet temperature is the temperature when the coolant enters the radiator, and the radiator outlet temperature is the temperature when the coolant exits the radiator. If the temperature difference between the inlet and outlet of the radiator is not greater than the radiator temperature difference threshold, indicating that the radiator is malfunctioning, then output an alarm message for the fan and control the operating power of the fuel cell system to be within the restricted operating power range, that is, restrict the operating power of the fuel cell system. If the temperature difference between the inlet and outlet of the radiator is greater than the radiator temperature difference threshold, indicating that the radiator is operating normally, then output information indicating that the radiator is operating normally.

[0104] It should be noted that both the radiator temperature difference threshold and the restricted operating power range are set according to actual requirements, and the radiator temperature difference threshold is usually set to 5°C.

[0105] This embodiment can intelligently detect the working state of the fan. When there is an abnormality in the fan, it can promptly detect the fan failure, send out an alarm message for the fan, restrict the power output of the fuel cell system, ensure that the fuel cell system will not be irreversibly damaged due to abnormal temperature, improve the stability and reliability of the fuel cell system, and achieve precise control of the fuel cell system.

[0106] One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:

[0107] In this embodiment, after the fuel cell system of the vehicle is started, first obtain the coolant inlet temperature of the fuel cell system. Then judge the coolant inlet temperature to determine whether the fuel cell system enters the heat preservation mode. If the coolant inlet temperature is not less than the heat preservation temperature threshold, then control the fuel cell system to enter the heat preservation mode.

[0108] In the heat preservation mode, control the small circulation loop of the fuel cell system to be in the closed state and the large circulation loop to be in the open state, and in the large circulation loop, determine the actual pump speed of the water pump and the actual fan speed of the fan of the fuel cell system according to the required power of the fuel cell system. Here, according to the power demand and temperature demand of the fuel cell system, regulate the fuel cell system, and ensure the stability of the fuel cell system when the power of the fuel cell system fluctuates, avoid unnecessary energy waste, and achieve precise control of the fuel cell system.

[0109] Embodiment 2

[0110] Based on the same inventive concept, the second embodiment of the present invention also provides a control device for a fuel cell system, as Figure 7 shown, including:

[0111] An acquisition module 201, configured to acquire the coolant inlet temperature of the fuel cell system after the fuel cell system of the vehicle is started;

[0112] A judgment module 202, configured to control the fuel cell system to enter a heat preservation mode if the coolant inlet temperature is not less than a heat preservation temperature threshold;

[0113] A control module 203, configured to, in the heat preservation mode, control the small circulation loop of the fuel cell system to be in a closed state and the large circulation loop to be in an open state, and in the large circulation loop, determine the actual water pump speed of the water pump and the actual fan speed of the fan of the fuel cell system according to the required power of the fuel cell system.

[0114] As an optional embodiment, the determining the actual water pump speed of the water pump of the fuel cell system according to the required power of the fuel cell system in the large circulation loop includes:

[0115] Obtaining a set water pump speed of the water pump and a target temperature difference between the inlet and outlet of the fuel cell system according to the required power;

[0116] Obtaining a water pump speed correction amount of the water pump according to the target temperature difference between the inlet and outlet;

[0117] Obtaining the actual water pump speed according to the set water pump speed and the water pump speed correction amount.

[0118] As an optional embodiment, the determining the actual fan speed of the fan of the fuel cell system according to the required power of the fuel cell system in the large circulation loop includes:

[0119] Obtaining a set fan speed of the fan and a target outlet temperature of the fuel cell system according to the required power;

[0120] Obtaining a fan speed correction amount of the fan according to the target outlet temperature;

[0121] Obtaining the actual fan speed according to the set fan speed and the fan speed correction amount.

[0122] As an optional embodiment, the judgment module 202 is configured to, in the heat preservation mode, if it is detected that the coolant inlet temperature is not greater than a temperature increase threshold, control the fuel cell system to switch from the heat preservation mode to a temperature increase mode, where the temperature increase threshold is less than the heat preservation temperature threshold;

[0123] The control module 203 is configured to, in the temperature increase mode, control the small circulation loop to be in an open state and the large circulation loop to be in a closed state.

[0124] As an alternative embodiment, during the process of controlling the small circulation loop to be in an open state, the actual pump speed is determined according to the required power.

[0125] As an alternative embodiment, the control module 203 is configured to: after determining the actual pump speed, obtain the current pump speed of the pump;

[0126] If the current pump speed is not less than the pump speed threshold, within a first preset duration, control the fuel cell system to operate at a first actual power;

[0127] After controlling the fuel cell system to operate at the first actual power within the first preset duration, obtain the current temperature difference between the inlet and outlet of the fuel cell stack of the fuel cell system;

[0128] If the current temperature difference between the inlet and outlet of the stack is not greater than the temperature difference threshold, output an alarm message of the pump and turn off the fuel cell system.

[0129] As an alternative embodiment, the control module 203 is configured to: after determining the actual fan speed, obtain the current fan speed of the fan;

[0130] If the current fan speed is not less than the fan speed threshold, within a second preset duration, control the fuel cell system to operate at a second actual power;

[0131] After controlling the fuel cell system to operate at the second actual power within the second preset duration, obtain the temperature difference between the inlet and outlet of the radiator of the fuel cell system;

[0132] If the temperature difference between the inlet and outlet of the radiator is not greater than the radiator temperature difference threshold, output an alarm message of the fan and control the operating power of the fuel cell system to be within the restricted operating power range.

[0133] As an alternative embodiment, the judgment module 202 is configured to: after obtaining the coolant inlet temperature of the fuel cell system, if the coolant inlet temperature is less than the heat preservation temperature threshold, control the fuel cell system to enter the heating mode;

[0134] The judgment module 202 is configured to: in the heating mode, if it is detected that the coolant inlet temperature is not less than the heat preservation temperature threshold, control the fuel cell system to switch from the heating mode to the heat preservation mode.

[0135] Since the control device of the fuel cell system introduced in this embodiment is the device adopted to implement the control method of the fuel cell system in Embodiment 1 of the present application, based on the control method of the fuel cell system introduced in Embodiment 1 of the present application, those skilled in the art can understand the specific implementation manners and various variations of the control device of the fuel cell system in this embodiment. Therefore, the implementation of how the control device of the fuel cell system realizes the method in Embodiment 1 of the present application will not be described in detail here. As long as those skilled in the art implement the device adopted for the control method of the fuel cell system in Embodiment 1 of the present application, it falls within the scope protected by the present application.

[0136] Embodiment 3

[0137] Based on the same inventive concept, the third embodiment of the present invention further provides a fuel cell vehicle, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, it implements the steps of any one of the above control methods of the fuel cell system.

[0138] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can 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.

[0139] The present invention is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram can be implemented by computer program instructions, and the combination of flows and / or blocks in the flowchart and / or block diagram can also be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for implementing the specified functions in Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0140] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory generate a manufactured article including an instruction device, and the instruction device implements the specified functions in Figure 1 one process or multiple processes and / or blocks Figure 1The functions specified in one or more boxes.

[0141] These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process. Thus, the instructions executed on the computer or other programmable device provide for implementing the steps of the functions specified in one or more processes and / or boxes Figure 1 One process or more processes and / or boxes Figure 1 The steps of the functions specified in one box or more boxes.

[0142] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications once they learn the basic creative concepts. Therefore, the appended claims are intended to be construed as including the preferred embodiments as well as all changes and modifications falling within the scope of the present invention.

[0143] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations.

Claims

1. A control method for a fuel cell system, characterized in that, Including: After the fuel cell system of the vehicle is started, obtain the coolant inlet temperature of the fuel cell system; If the coolant inlet temperature is not less than the heat preservation temperature threshold, control the fuel cell system to enter the heat preservation mode; In the heat preservation mode, control the small circulation loop of the fuel cell system to be in a closed state and the large circulation loop to be in an open state, and in the large circulation loop, determine the actual pump speed of the water pump of the fuel cell system and the actual fan speed of the fan according to the required power of the fuel cell system; The determining the actual pump speed of the water pump of the fuel cell system according to the required power of the fuel cell system in the large circulation loop includes: obtaining the set pump speed of the water pump and the target temperature difference between the inlet and outlet of the fuel cell system according to the required power; obtaining the pump speed correction amount of the water pump according to the target temperature difference between the inlet and outlet; and obtaining the actual pump speed according to the set pump speed and the pump speed correction amount; The determining the actual fan speed of the fan of the fuel cell system according to the required power of the fuel cell system in the large circulation loop includes: obtaining the set fan speed of the fan and the target outlet temperature of the fuel cell system according to the required power; obtaining the fan speed correction amount of the fan according to the target outlet temperature; and obtaining the actual fan speed according to the set fan speed and the fan speed correction amount.

2. The method according to claim 1, wherein In the heat preservation mode, it further includes: If it is detected that the coolant inlet temperature is not greater than the temperature rising temperature threshold, control the fuel cell system to switch from the heat preservation mode to the temperature rising mode, where the temperature rising temperature threshold is less than the heat preservation temperature threshold; In the temperature rising mode, control the small circulation loop to be in an open state and the large circulation loop to be in a closed state.

3. The method according to claim 2, wherein In the process of controlling the small circulation loop to be in an open state, it further includes: Determine the actual pump speed according to the required power.

4. The method according to any one of claims 1 or 3, characterized in that, After determining the actual pump speed, it further includes: Obtain the current pump speed of the water pump; If the current pump speed is not less than the pump speed threshold, control the fuel cell system to operate at a first actual power within a first preset time period; After controlling the fuel cell system to operate at the first actual power within the first preset time period, obtain the current temperature difference between the inlet and outlet of the fuel cell system; If the current temperature difference between the inlet and outlet is not greater than the temperature difference threshold, output the alarm information of the water pump and shut down the fuel cell system.

5. The method according to claim 1, characterized in that After determining the actual fan speed, it further includes: Obtain the current fan speed of the fan; If the current fan speed is not less than the fan speed threshold, control the fuel cell system to operate at a second actual power within a second preset time period; After controlling the fuel cell system to operate at the second actual power within the second preset time period, obtain the temperature difference between the inlet and outlet of the radiator of the fuel cell system; If the temperature difference between the inlet and outlet of the radiator is not greater than the radiator temperature difference threshold, output the alarm information of the fan and control the operating power of the fuel cell system to be within the restricted operating power range.

6. The method according to claim 2, wherein After obtaining the coolant inlet temperature of the fuel cell system, it further includes: If the coolant inlet temperature is less than the heat preservation temperature threshold, control the fuel cell system to enter the heating mode; In the heating mode, if it is detected that the coolant inlet temperature is not less than the heat preservation temperature threshold, control the fuel cell system to switch from the heating mode to the heat preservation mode.

7. A control device for a fuel cell system, characterized in that, It includes: An acquisition module for obtaining the coolant inlet temperature of the fuel cell system after the fuel cell system of the vehicle is started; A judgment module for controlling the fuel cell system to enter the heat preservation mode if the coolant inlet temperature is not less than the heat preservation temperature threshold; A control module for, in the heat preservation mode, controlling the small circulation loop of the fuel cell system to be in a closed state and the large circulation loop to be in an open state, and in the large circulation loop, determining the actual pump speed of the water pump of the fuel cell system and the actual fan speed of the fan according to the required power of the fuel cell system; The step of determining the actual pump speed of the water pump of the fuel cell system according to the required power of the fuel cell system in the large circulation loop includes: obtaining the set pump speed of the water pump and the target temperature difference between the inlet and outlet of the fuel cell system according to the required power; obtaining the pump speed correction amount of the water pump according to the target temperature difference between the inlet and outlet; and obtaining the actual pump speed according to the set pump speed and the pump speed correction amount; The step of determining the actual fan speed of the fan of the fuel cell system according to the required power of the fuel cell system in the large circulation loop includes: obtaining the set fan speed of the fan and the target outlet temperature of the fuel cell system according to the required power; obtaining the fan speed correction amount of the fan according to the target outlet temperature; and obtaining the actual fan speed according to the set fan speed and the fan speed correction amount.

8. A fuel cell vehicle, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the method steps described in any one of claims 1-6.

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