Thermal management system and thermal management method of fuel cell vehicle

Abstract

The invention relates to a thermal management system and a thermal management method of a fuel cell vehicle, the system comprises a fuel cell system and a cabin warm air loop, and the fuel cell system comprises a fuel cell loop and an anode heating pipeline; the fuel cell loop is used for heating or cooling an electric pile of the fuel cell system and comprises a first heater; the cabin warm air loop is used for heating the cabin and comprises a second heater; the anode heating pipeline passes through an anode gas transmission structure of the fuel cell system and is communicated with the fuel cell loop and the cabin warm air loop, so that heat exchange media in the two loops can exchange and circulate with each other, and the two loops can heat the heat exchange media at the same time when the vehicle is started; and heat is jointly supplied to the electric pile, the cabin and / or the anode gas transmission structure through a heat exchange medium. The anode heating pipeline is arranged to pass through the anode gas transmission structure, heat can be supplied to the electric pile, the cabin and / or the anode gas transmission structure by means of heat exchange media of two loops, and the problems that the system is frozen and the cold start speed is low are solved.

Description

Technical Field

[0001] The present application relates to the technical field of thermal management of fuel cell system vehicles, and more specifically, to a thermal management system and a thermal management method for fuel cell vehicles. Background Art

[0002] A fuel cell vehicle is a means of transportation equipped with a fuel cell system with the fuel cell system as the core. Generally, it is divided into pure electric mode and hybrid mode depending on whether the fuel cell system is started. The pure electric mode relies on the on-board power battery to provide electricity, while the hybrid mode is the working mode of turning on the fuel cell system, with the fuel cell system as the main source of electricity.

[0003] The fuel cell system consists of a hydrogen supply system, an air supply system and a thermal management system. The hydrogen supplied by the hydrogen supply system and the air supplied by the air supply system generate electricity and release a large amount of heat under the action of the catalyst inside the fuel cell system. When the system is running, the thermal management system needs to discharge this part of the heat out of the system to ensure that the fuel cell system operates within a suitable temperature range.

[0004] Hydrogen, as a raw material consumed during the operation of the fuel cell system, needs to be transported from an external hydrogen storage device to the fuel cell stack through a hydrogen supply pipeline for consumption in the fuel cell stack reaction. After the hydrogen fuel cell system reacts, the components of the hydrogen discharged from the fuel cell stack include: water produced by the reaction, incompletely reacted hydrogen, nitrogen permeated from the air side, and a small amount of air. From an economic point of view, it is necessary to separate the incompletely reacted hydrogen from the product exhaust gas and then participate in subsequent reactions for consumption.

[0005] Among them, the water produced by the reaction will cause the hydrogen supply system to freeze under low temperature conditions such as winter, affecting the normal start of the vehicle. Although there is an air purge mechanism in the prior art that can partially remove water, icing is still inevitable in the face of harsh environments. In addition, in a low temperature environment, the start-up of the fuel cell system of a fuel cell vehicle will also be affected by the low temperature. Although the existing thermal management system has a stack preheating function, the heating effect is slow, which makes it impossible to quickly start the fuel cell system, affecting the driving experience. Summary of the invention

[0006] The present application provides a thermal management system and a thermal management method for a fuel cell vehicle to solve the problems of icing and slow cold start when the fuel cell vehicle is started at low temperatures in the prior art.

[0007] According to one aspect of the present application, a thermal management system of a fuel cell vehicle is provided, the thermal management system comprising: a fuel cell system and a cabin heating circuit, the fuel cell system comprising a fuel cell circuit and an anode heating pipe;

[0008] The fuel cell circuit is used to heat or cool the fuel cell stack of the fuel cell system, and includes a first heater;

[0009] The cabin heating circuit is used to heat the cabin and includes a second heater;

[0010] The anode heating pipeline passes through the anode gas supply structure of the fuel cell system and connects the fuel cell circuit and the cabin heating circuit, so that the heat exchange medium in the two circuits can be exchanged and circulated with each other, so that the two circuits can heat the heat exchange medium at the same time when the vehicle is started, and jointly provide heat for the fuel cell stack, cabin and / or anode gas supply structure through the heat exchange medium.

[0011] In some embodiments, the anode gas delivery structure includes: a hydrogen circulation pump and an anode gas-liquid separator, the hydrogen circulation pump is connected to the anode hydrogen inlet of the fuel cell stack, the anode gas-liquid separator is connected to the anode hydrogen outlet of the fuel cell stack, the anode gas-liquid separator includes a nitrogen exhaust valve and a water exhaust valve, a heat exchange water jacket is provided on the outside of the anode gas-liquid separator, the anode heating pipeline passes through the heat exchange medium channel and the heat exchange water jacket of the hydrogen circulation pump, the inlet of the anode heating pipeline is connected to the fuel cell circuit, and the outlet of the anode heating pipeline is connected to the cabin heating circuit;

[0012] A pressure sensor is provided on the outlet side of the hydrogen circulation pump, and an air intake valve is provided on the inlet side of the hydrogen circulation pump.

[0013] In some embodiments, the fuel cell circuit includes: a first water pump, a bypass valve, a deionizer, a first heater, a radiator, a cooling fan, and an overflow kettle;

[0014] The outlet of the first water pump is respectively connected to the medium inlet of the fuel cell stack and the inlet of the anode heating pipe, the medium outlet of the fuel cell stack is connected to the first end of the bypass valve, the second end of the bypass valve is connected to the inlet of the first water pump via the radiator, the third end of the bypass valve is connected to the inlet of the first water pump via the deionizer and the first heater, the cooling fan is arranged at the radiator, the inlet of the overflow pot is connected to the outlet of the radiator, and the outlet of the overflow pot is connected to the inlet of the first water pump; a first temperature sensor is arranged on the medium outlet side of the fuel cell stack.

[0015] In some embodiments, the cabin heating circuit includes: a three-way proportional valve, a second heater, a second water pump, a heating core, and a heating fan;

[0016] The first end of the three-way proportional valve is connected to the outlet of the anode heating pipe, the second end of the three-way proportional valve is connected to the outlet of the heater core, the third end of the three-way proportional valve is connected to the inlet of the heater core via the second heater and the second water pump, and the outlet of the heater core is connected to the inlet of the deionizer of the fuel cell circuit through the return pipe;

[0017] A second temperature sensor is arranged on the inlet side of the warm air core.

[0018] According to another aspect of the present application, a thermal management method for a fuel cell vehicle is provided, which is applied to the thermal management system of the fuel cell vehicle as described above, and the method comprises:

[0019] When the vehicle is started, the enabling state of the fuel cell system and the stack temperature T1 are detected to control the fuel cell circuit and the cabin heating circuit according to the detection results;

[0020] If the fuel cell system is in the enabled state and the stack temperature T1 is lower than the minimum temperature T0, it is judged that this is a cold start, and the first heater of the fuel cell circuit and the second heater of the cabin heating circuit are started, and the heat exchange medium is controlled to circulate between the two circuits through the anode heating pipeline and does not flow through the stack of the fuel cell system, so as to heat the cabin and the anode gas transmission structure;

[0021] Monitor the cabin temperature T3. When the cabin temperature T3 rises to the preset cabin temperature TS, perform a leak detection on the anode gas supply structure to determine whether the anode gas supply structure is normal.

[0022] If the anode gas supply structure is normal, the heat exchange medium is controlled to flow through the fuel cell system stack to heat the stack. When the stack temperature T1 rises to the first threshold value T11, the fuel cell system is started.

[0023] In some embodiments, the anode gas transmission structure includes a hydrogen circulation pump and an anode gas-liquid separator, and performing a leak detection on the anode gas transmission structure to determine whether the anode gas transmission structure is normal includes:

[0024] Open the air intake valve on the air intake side of the hydrogen circulation pump of the anode gas transmission structure, and close the air intake valve after the anode gas pressure of the fuel cell system reaches the preset air pressure value; then open the nitrogen exhaust valve and the water drain valve of the anode gas-liquid separator respectively to obtain the corresponding air pressure drop rate. If the air pressure drop rate is lower than the calibration value, it is judged that the nitrogen exhaust valve or the water drain valve has ice abnormality, otherwise it is judged to be normal;

[0025] A test run command is issued to the hydrogen circulation pump to obtain the speed feedback value of the hydrogen circulation pump. If the speed feedback value is zero, it is determined that the hydrogen circulation pump has icing abnormality, otherwise it is determined to be normal.

[0026] In some embodiments, after performing a leak detection on the anode gas delivery structure, if it is determined that an abnormality exists, emergency heating is initiated;

[0027] Control the first heater and the second heater to operate at full power, and at the same time increase the circulation flow of the heat exchange medium. After a preset time, perform a leak detection on the anode gas transmission structure again;

[0028] If the result of the re-test is normal, the heat exchange medium is controlled to flow through the fuel cell stack to heat the fuel cell stack. When the fuel cell stack temperature T1 rises to the first threshold value T11, the fuel cell system is started;

[0029] If the abnormality is still found after the re-detection, an alarm message will be issued to indicate vehicle failure.

[0030] In some embodiments, when the vehicle is started,

[0031] If it is detected that the fuel cell system is in the enabled state, but the stack temperature T1 is not lower than the minimum preset temperature T0, it is determined that this is a hot engine start and the fuel cell system is started normally;

[0032] If it is detected that the fuel cell system is in a disabled state and the cabin temperature T3 is lower than the preset cabin temperature TS, the second heater of the cabin heating circuit is started separately to heat the cabin independently through the cabin heating circuit.

[0033] In some embodiments, after the vehicle is started, when the cabin temperature T3 is less than the preset cabin temperature TS, the stack temperature T1 is detected. If it is detected that the stack temperature T1 meets the waste heat utilization condition, the heat exchange medium is controlled to circulate between the fuel cell circuit and the cabin heating circuit through the anode heating pipe, and the waste heat of the stack is used to heat the cabin. Otherwise, the second heater of the cabin heating circuit is turned on, and the second heater is used to heat the cabin alone, and the stack temperature T1 is monitored in real time;

[0034] If it is monitored that the temperature T1 of the stack rises to meet the waste heat utilization conditions, the heat exchange medium is controlled to circulate between the fuel cell circuit and the cabin heating circuit through the anode heating pipe, and the second heater is turned off to use the waste heat of the stack to heat the cabin;

[0035] The waste heat utilization conditions include: the stack temperature T1 reaches the second threshold value T12, or, although the stack temperature T1 does not reach the second threshold value T12, the difference between the stack temperature T1 and the cabin temperature T3 is less than a preset value.

[0036] In some embodiments, when the stack temperature T1 rises to a third threshold value T13, the cooling function of the fuel cell circuit is activated to cool the stack and control the stack temperature T1 to remain within a preset temperature range.

[0037] The technical solution of the present application is to set an anode heating pipeline passing through the anode gas supply structure of the fuel cell system. The anode heating pipeline is connected to the medium channel of the fuel cell circuit and the cabin heating circuit, and can heat the anode gas supply structure with the help of the heat exchange medium in the two circuits, thereby overcoming the abnormal hydrogen pumping problem of the fuel cell system caused by system icing during startup. In addition, since the anode heating pipeline is connected to the fuel cell circuit and the cabin heating circuit, the two heaters of the fuel cell circuit and the cabin heating circuit can work together to heat different heating areas at the same time, and a smaller amount of heat exchange medium is involved in the temperature control process, and the cabin heating and low-temperature cold start speed of the fuel cell system are greatly improved, thereby improving the driving experience of fuel cell vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0039] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0040] Figure 1 A schematic diagram showing the structure of a thermal management system for a fuel cell vehicle according to an embodiment of the present application is shown;

[0041] Figure 2 A schematic diagram showing a flow chart of a thermal management method for a fuel cell vehicle according to an embodiment of the present application;

[0042] Figure 3 An overall schematic diagram showing the execution process of a thermal management method for a fuel cell vehicle according to an embodiment of the present application is shown;

[0043] Figure 4 A schematic diagram of the execution process of a thermal management process in a fault-free state based on a fuel-electric cold start branch in an embodiment of the present application is shown;

[0044] Figure 5 A schematic diagram of the leak detection and emergency heating execution process of the anode gas transmission structure in the thermal management process of one embodiment of the present application is shown;

[0045] Figure 6 A schematic diagram of the execution process of the cabin heating flow based on a non-fuel and electric starting branch in the thermal management process of an embodiment of the present application is shown.

[0046] The above drawings include the following reference numerals:

[0047] 1. Hydrogen storage mechanism; 2. Pressure reducing valve; 3. Proportional regulating valve; 4. Hydrogen circulation pump; 5. Pressure sensor; 6. Anode gas-liquid separator; 7. Nitrogen exhaust valve; 8. Drain valve; 9. Tail exhaust; 10. Third temperature sensor; 11. Three-way proportional valve; 12. Second heater; 13. Second water pump; 14. Second temperature sensor; 15. Warm air fan; 16. Warm air core; 17. Reflux pipe; 18. First water pump; 19. First temperature sensor; 20. Bypass valve; 21. Deionizer; 22. First heater; 23. Cooling fan; 24. Radiator; 25. Overflow kettle; 26. Anode heating pipe; 27. Fuel stack; 28. Electronic control device. DETAILED DESCRIPTION

[0048] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0049] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0050] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used herein to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" may include both "above" and "below". The device may also be positioned in other different ways, rotated 90 degrees or in other orientations, and the spatially relative descriptions used herein are interpreted accordingly.

[0051] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0052] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0053] In the prior art, fuel cell vehicles produce water during the reaction, so there is a problem of freezing at low temperatures, which affects the start-up of the fuel cell system. In addition, when fuel cell vehicles encounter low temperatures, there is a need to heat the fuel cell system stack and the cabin, but the existing fuel cell vehicle thermal management system cannot make good use of limited heat sources for heating, which leads to the problem of slow cold start speed of fuel cell vehicles. This application solves the icing problem of fuel cell vehicles by designing a fuel cell vehicle thermal management system, while improving the cold start speed of fuel cell vehicles.

[0054] refer to Figure 1 As shown, Figure 1 A schematic structural diagram of a thermal management system of a fuel cell vehicle according to an embodiment of the present application is shown. The thermal management system includes: a fuel cell system and a cabin heating circuit. The fuel cell system includes a fuel cell circuit and an anode heating pipe 26 .

[0055] The fuel cell circuit is used to heat or cool the fuel cell stack 27 of the fuel cell system, and includes a first heater 22 .

[0056] The cabin heating circuit is used for heating the cabin and includes a second heater 12 .

[0057] The anode heating pipe 26 passes through the anode gas supply structure of the fuel cell system and connects the fuel cell circuit and the cabin heating circuit, so that the heat exchange medium in the two circuits can be exchanged and circulated with each other, so that the two circuits can heat the heat exchange medium at the same time when the vehicle is started, and jointly provide heat for the battery stack 27, the cabin and / or the anode gas supply structure through the heat exchange medium, thereby overcoming the icing problem at startup and accelerating the cold start speed of the fuel cell vehicle.

[0058] Based on the above technical solution of the present application, the thermal management system of the present application is provided with an anode heating pipe 26, which passes through the anode gas supply structure and connects the medium channels of the fuel cell circuit and the cabin heating circuit. Thus, the anode heating pipe 26 can heat the anode gas supply structure with the help of the heat exchange medium in the two circuits to overcome the abnormal problem of hydrogen pumping into the fuel cell system caused by system icing at startup.

[0059] In addition, since the anode heating pipe 26 connects the fuel cell circuit and the cabin heating circuit, the two heaters of the fuel cell circuit and the cabin heating circuit can work together at the same time to heat different heating areas (such as the fuel cell stack 27, the cabin or the anode gas supply structure), and a smaller amount of heat exchange medium is involved in the temperature control process. The dual-circuit heaters work together, which greatly improves the cabin heating and the low-temperature cold start speed of the fuel cell system, thereby improving the driving experience of the fuel cell vehicle.

[0060] At the same time, the embodiment of the present application uses the anode heating pipe 26 to achieve the connected circulation of the heat exchange medium, which is also beneficial to reduce the amount of heat exchange medium used, simplify the vehicle's medium circulation pipeline design, and achieve structural optimization of the fuel cell vehicle.

[0061] In some embodiments of the present application, reference Figure 1 As shown, the anode gas transmission structure includes: a hydrogen circulation pump 4 and an anode gas-liquid separator 6. The hydrogen circulation pump 4 is connected to the anode hydrogen inlet of the stack 27 for pumping in hydrogen. The anode gas-liquid separator 6 is connected to the anode hydrogen outlet of the stack 27 for gas-water separation of the discharged hydrogen, recycling hydrogen and discharging wastewater and other products. The anode gas-liquid separator 6 includes a nitrogen discharge valve 7 and a drain valve 8. The nitrogen discharge valve 7 and the drain valve 8 are connected to the tail drain 9 for exhaust gas and wastewater discharge. A heat exchange water jacket (not shown) is provided on the outside of the anode gas-liquid separator 6. The anode heating pipeline 26 passes through the heat exchange medium channel and the heat exchange water jacket of the hydrogen circulation pump 4, thereby delivering heat to the hydrogen circulation pump 4, the nitrogen discharge valve 7 and the drain valve 8 to solve the icing problem of these structures.

[0062] The inlet of the anode heating pipe 26 is connected to the fuel cell circuit, so that the heat exchange medium flows in from the fuel cell circuit, and the outlet of the anode heating pipe 26 is connected to the cabin heating circuit, so that the heat exchange medium flows out to the cabin heating circuit. It can be understood that the cabin heating circuit has a return pipe 17 for the heat exchange medium to flow back to the fuel cell circuit. The return pipe 17 is not responsible for the heating function, so this embodiment does not limit the arrangement position of the return pipe 17 in the vehicle.

[0063] refer to Figure 1 As shown, a pressure sensor 5 is provided at the outlet side of the hydrogen circulation pump 4 for measuring the anode gas pressure P1, and an intake valve is provided at the inlet side of the hydrogen circulation pump 4, which is connected to the hydrogen storage mechanism 1 for controlling the hydrogen flow. Figure 1 In the illustrated embodiment, the air intake valve includes a pressure reducing valve 2 and a proportional regulating valve 3 .

[0064] In some embodiments of the present application, Figure 1 As shown, the fuel cell circuit includes: a first water pump 18 , a bypass valve 20 , a deionizer 21 , a first heater 22 , a radiator 24 , a cooling fan 23 and an overflow kettle 25 .

[0065] The outlet of the first water pump 18 is connected to the medium inlet of the stack 27 and the inlet of the anode heating pipe 26 respectively. The medium outlet of the stack 27 is connected to the first end of the bypass valve 20. The second end of the bypass valve 20 is connected to the inlet of the first water pump 18 via the radiator 24. The third end of the bypass valve 20 is connected to the inlet of the first water pump 18 via the deionizer 21 and the first heater 22. The deionizer 21 is used to remove conductive ions in the heat exchange medium. The cooling fan 23 is arranged at the radiator 24, the inlet of the overflow pot 25 is connected to the outlet of the radiator 24, and the outlet of the overflow pot 25 is connected to the inlet of the first water pump 18; the first temperature sensor 19 is arranged on the medium outlet side of the stack 27, and the temperature sensed by the first temperature sensor 19 is the stack temperature T1.

[0066] In some embodiments of the present application, Figure 1 As shown, the cabin heating circuit includes: a three-way proportional valve 11 , a second heater 12 , a second water pump 13 , a heating core 16 and a heating fan 15 .

[0067] The first end of the three-way proportional valve 11 is connected to the outlet of the anode heating pipe 26, the second end of the three-way proportional valve 11 is connected to the outlet of the heater core 16, the third end of the three-way proportional valve 11 is connected to the inlet of the heater core 16 via the second heater 12 and the second water pump 13, and the outlet of the heater core 16 is connected to the inlet of the deionizer 21 of the fuel cell circuit through the reflux pipe 17.

[0068] A second temperature sensor 14 is provided at the inlet side of the heater core 16 , and the temperature sensed by the second temperature sensor 14 is the actual temperature T2 of the cabin heater circuit.

[0069] In addition, if Figure 1 As shown, in the embodiment of the present application, a third temperature sensor 10 is further provided in the cabin. The third temperature sensor 10 is used to sense the cabin temperature T3 so as to perform real-time temperature monitoring of the cabin.

[0070] In some embodiments of the present application, reference Figure 1As shown, the thermal management system of the embodiment of the present application also includes an electronic control device 28, which is used to electrically connect the fuel cell circuit, the cabin heating circuit and various temperature and pressure sensors to receive the detection data of each sensor, perform logical operations to generate control instructions, and control the actions of various valves, heaters, fans and other actuators in each circuit.

[0071] According to another aspect of the present application, the present application also discloses a thermal management method for a fuel cell vehicle, which is applied to the thermal management system of the fuel cell vehicle in the above embodiments. Figure 2 The schematic diagram of the process of the thermal management method of the present application is shown as follows: Figure 2 As shown, the thermal management method includes:

[0072] Step S210 , when the vehicle is started, the enabling state of the fuel cell system and the stack temperature T1 are detected to control the fuel cell circuit and the cabin heating circuit according to the detection results.

[0073] By detecting the enabled state of the fuel cell system, it can be determined whether the vehicle is started in pure electric mode or hybrid mode; by detecting the stack temperature T1, it can be determined whether the vehicle is in a low-temperature environment, so as to decide whether heating and defrosting measures are needed.

[0074] Step S220, if the fuel cell system is in an enabled state and the stack temperature T1 is lower than the minimum temperature T0, it is determined that this is a cold start, and the first heater 22 of the fuel cell circuit and the second heater 12 of the cabin warm air circuit are started, and the heat exchange medium is controlled to circulate between the two circuits through the anode heating pipe 26 and does not flow through the stack 27 of the fuel cell system, so as to heat the cabin and the anode gas supply structure.

[0075] When the stack temperature T1 is lower than the minimum temperature T0 (T0 can be set to 0°C), there will be a risk of icing. At this time, the vehicle is judged to be cold-started. While giving priority to protecting the temperature safety of passengers, de-icing is performed for the start-up of the fuel cell system. The first heater 22 and the second heater 12 are started, and the heat exchange medium is controlled to circulate between the two circuits through the anode heating pipe 26, and does not flow through the stack 27, so as to maximize the use of the two circuits The heaters work together to achieve a rapid increase in the cabin temperature and simultaneously solve the icing problem of the anode gas transmission structure such as the hydrogen circulation pump 4, the nitrogen exhaust valve 7 and the drain valve 8.

[0076] Step S230, monitoring the cabin temperature T3, when the cabin temperature T3 rises to the preset cabin temperature TS, performing a leak detection on the anode gas supply structure to determine whether the anode gas supply structure is normal.

[0077] The preset cabin temperature TS is the minimum temperature to protect passengers from frostbite or to avoid frost on the cabin glass, and its specific value can be set according to demand. When the cabin temperature T3 rises to the preset cabin temperature TS, it can be considered that the cabin temperature requirement has been met. At the same time, since step S220 simultaneously performs heating and de-icing treatment of the anode gas supply structure during the cabin heating stage, the anode heating pipe 26 has also continuously heated the anode gas supply structure for a certain period of time at this moment, and the state detection of the anode gas supply structure can be started to determine whether the fuel cell system can start. In addition, regardless of whether the anode gas supply structure such as the hydrogen circulation pump 4 has an icing problem, the heat transported by the anode heating pipe 26 to the anode gas supply structure will eventually be brought into the fuel cell stack 27 through the intake air, so this process actually realizes the preheating of the fuel cell stack 27, which is beneficial to the heating of the fuel cell stack 27 without causing heat waste.

[0078] Step S240, if the anode gas supply structure is normal, the heat exchange medium is controlled to flow through the fuel cell stack 27 of the fuel cell system to heat the fuel cell stack 27, and when the stack temperature T1 rises to the first threshold value T11, the fuel cell system is started.

[0079] When the anode gas delivery structure is detected to be in a normal state, the stack 27 can be heated to start the fuel cell system. Moreover, since the first heater 22 and the second heater 12 are still working together at this stage, compared with the prior art, the thermal management method of the embodiment of the present application can make fuller use of the vehicle heating structure to heat the stack 27, so that the stack 27 heats up faster, and thus the cold start speed of the vehicle is ultimately improved.

[0080] It can be seen that the thermal management method of the embodiment of the present application, during a low-temperature cold start, simultaneously starts the fuel cell circuit and the cabin heating circuit, and through the coordinated work of the heaters of the two circuits, the cabin temperature, the anode gas structured ice and the stack 27 temperature are heated, so that the heating capacity of the vehicle can be fully utilized, and the heating cycle circuits in the startup phase are clearly distinguished, without heat loss, and a sophisticated temperature control strategy is achieved with less heat exchange medium, which effectively solves the cold start icing problem, and the cabin temperature and the stack 27 temperature rise rapidly, greatly improving the cold start speed of the vehicle.

[0081] In some embodiments of the present application, when the vehicle is started, if it is detected that the fuel cell system is in a disabled state, the above cold start step does not need to be performed, and the fuel cell circuit does not work at this time, and only the cabin heating circuit controls the cabin temperature. When the cabin temperature T3 is less than the preset cabin temperature TS, the second heater 12 of the cabin heating circuit is started separately, and the cabin is heated independently through the cabin heating circuit.

[0082] In some embodiments of the present application, when the vehicle is started, if it is detected that the fuel cell system is in an enabled state, but the stack temperature T1 is not lower than the minimum preset temperature T0, it is determined that this is a hot engine start, and there is no influence of low temperature icing, etc., and the fuel cell system is started normally. This process is no different from the conventional start process of existing fuel cell vehicles, and will not be described in detail here.

[0083] In some embodiments of the present application, the anode gas transmission structure includes a hydrogen circulation pump 4 and an anode gas-liquid separator 6. In step S230, a leak detection of the anode gas transmission structure is performed to determine whether the anode gas transmission structure is normal, including:

[0084] Open the air intake valve on the air intake side of the hydrogen circulation pump 4, and after the anode gas pressure of the fuel cell system reaches the preset air pressure value, close the air intake valve; then open the nitrogen exhaust valve 7 and the water drain valve 8 of the anode gas-liquid separator 6 respectively, and obtain the corresponding air pressure drop rate. If the air pressure drop rate is lower than the calibration value, it is judged that the nitrogen exhaust valve 7 or the water drain valve 8 has an abnormal icing, otherwise it is judged to be normal;

[0085] A test operation instruction is issued to the hydrogen circulation pump 4 to obtain a rotation speed feedback value of the hydrogen circulation pump 4. If the rotation speed feedback value is zero, it is determined that the hydrogen circulation pump 4 has an icing abnormality, otherwise it is determined to be normal.

[0086] When the nitrogen exhaust valve 7 or the water drain valve 8 is frozen, it will cause the airway to be blocked and affect the gas circulation, which is ultimately reflected in the gas pressure drop rate. The embodiment of the present application determines whether the valve is frozen by the gas pressure drop rate. The speed feedback of the hydrogen circulation pump 4 directly indicates whether the hydrogen circulation pump 4 is frozen and cannot rotate.

[0087] In some embodiments of the present application, after performing a leak detection on the anode gas supply structure, if it is determined that an abnormality exists, emergency heating is started to try to solve the abnormal problem. Specifically, emergency heating includes: controlling the first heater 22 and the second heater 12 to operate at full power, while increasing the circulation flow of the heat exchange medium, and after a preset time (for example, 60s), the anode gas supply structure is tested for leaks again. If the result of the re-detection is normal, the cold start process step S240 is performed normally, and the heat exchange medium is controlled to flow through the stack 27 to heat the stack 27. When the stack temperature T1 rises to the first threshold value T11, the fuel cell system is started; if there is still an abnormality after the re-detection, an alarm message is issued to indicate a vehicle failure. At this time, the vehicle can be controlled to operate in pure electric mode, and a nearby maintenance point can be found for repair as soon as possible, or the vehicle can be rescued on the spot.

[0088] Some embodiments of the present application also set up a waste heat recovery link of the stack 27. Based on the different operating states of the fuel cell system, according to the temperature of the heat exchange medium of the fuel cell circuit and the temperature of the heat exchange medium of the vehicle heating circuit, the working states of the cabin heating circuit and the fuel cell circuit are reasonably allocated to use the waste heat of the stack 27 to heat the cabin, so that the waste heat utilization of the whole vehicle is balanced, the energy consumption is lower, and the effect is better. The waste heat utilization link exists in the hybrid mode when the fuel cell system is turned on. Regardless of whether the startup method is cold start or hot engine start, as long as there is usable waste heat in the fuel cell system, it can be used, such as Figure 3 and Figure 4 shown.

[0089] In some embodiments of the present application, after the vehicle is started, when the cabin temperature T3 is less than the preset cabin temperature TS, the stack temperature T1 is detected. If it is detected that the stack temperature T1 meets the waste heat utilization condition, the heat exchange medium is controlled to circulate between the fuel cell circuit and the cabin heating circuit through the anode heating pipe 26, and the waste heat of the stack 27 is directly used to heat the cabin. Otherwise, the second heater 12 of the cabin heating circuit is turned on, and the second heater 12 is used to heat the cabin alone, and the stack temperature T1 is monitored in real time, and then the fuel cell circuit and the cabin heating circuit are controlled according to the stack temperature T1.

[0090] If it is monitored that the stack temperature T1 rises to meet the waste heat utilization conditions, the heat exchange medium is controlled to circulate between the fuel cell circuit and the cabin heating circuit through the anode heating pipe 26, and the second heater 12 is turned off to use the waste heat of the stack 27 to heat the cabin.

[0091] Specifically, the waste heat utilization conditions include: when the stack temperature T1 reaches the second threshold value T12 (the second threshold value T12 is the temperature at which the stack 27 can work stably), or when the stack temperature T1 does not reach the second threshold value T12, but the difference between the stack temperature T1 and the cabin temperature T3 is less than a preset value. In the latter case, since the temperature difference between the stack 27 and the cabin is less than a specific preset value, heating the cabin with the stack 27 will not cause excessive cooling shock to the stack 27, and will not affect the normal operation of the stack 27. Therefore, at this time, the waste heat of the stack 27 can be used to heat the cabin. In this way, the waste heat of the stack 27 can be utilized earlier, which can further save energy.

[0092] In some other embodiments of the present application, when the waste heat of the battery stack 27 is used to heat the cabin, on the basis of ensuring that the battery stack 27 can operate normally, the first heater 22 and the second heater 12 can be turned off at the same time, and the waste heat of the battery stack 27 is used entirely to heat the cabin.

[0093] Some embodiments of the present application are also provided with a high-temperature cooling link to protect the normal operation of the battery stack 27.

[0094] Specifically, in some embodiments of the present application, when the stack temperature T1 rises to a third threshold value T13 (the third threshold value T13 is a high temperature warning line of the operating temperature of the fuel cell system, set to 60-65° C.), the cooling function of the fuel cell circuit is started. Figure 1 In the embodiment shown, the openings of ports ① and ② of the bypass valve 20 are dynamically adjusted to complete the diversion of the heat exchange medium of the stack 27, so that the heat exchange medium flows through the radiator 24, and at the same time, the speed of the first water pump 18 and the speed of the cooling fan 23 are dynamically adjusted based on the temperature T1 to cool the stack 27 and control the stack temperature T1 to remain within a preset temperature range. In a preferred embodiment, the stack temperature T1 is controlled to be: 65℃<T1≤80℃.

[0095] Figure 3 An overall schematic diagram of the execution process of a thermal management method for a fuel cell vehicle according to an embodiment of the present application is shown.

[0096] like Figure 3 As shown, when the vehicle is started, it can be determined whether the current start is in pure electric mode or hybrid mode based on whether the fuel cell system is enabled. When the fuel cell system is not enabled, it defaults to pure electric mode, and there is no need to start the fuel cell system. At this time, the non-fuel-electric start branch is executed. When the fuel cell system is enabled, the default is hybrid mode, and the fuel cell system needs to be started. At this time, if the stack temperature T1 < T0, it is determined to be a low-temperature cold start, and the fuel-electric cold start branch is executed, and the thermal management method steps of steps S210 to S240 in the above embodiment are performed to achieve a rapid cold start of the fuel cell system; if the stack temperature T1 ≥ T0, it is determined that this is a heat engine start without the influence of low temperature, and there is no need to perform stack heating and ice defrosting and leak detection of the anode gas supply structure, etc., and the fuel cell system can be started normally.

[0097] based on Figure 1 The thermal management system embodiment shown, Figure 4 A schematic diagram of the execution process based on the fuel-electric cold start branch in a fault-free state in one embodiment of the present application is shown.

[0098] like Figure 4As shown, first, the fuel cell circuit and the cabin heating circuit are controlled to heat synchronously, so as to quickly heat up the cabin and simultaneously solve the problem of structural ice on the anode gas transmission. In this stage, the heat exchange medium is controlled not to flow through the fuel cell stack 27 after passing through the first water pump 18, but only flows along the anode heating pipe 26. The specific execution is as follows: the bypass valve 20 executes: the openings of ports ② and ③ are 0, that is, no liquid can flow at the bypass valve 20, thereby preventing the heat exchange medium from flowing through the fuel cell stack 27. At this time, the heat exchange medium flows into the anode heating pipe 26 after flowing out of the first water pump 18; the three-way proportional valve 11 executes: the opening of port ② is 0, and ports ③ and ① are fully open; the first heater 22 runs at full power; the second heater 12 runs at full power; the second water pump 13 runs; at the same time, based on the cabin temperature T3 and the actual temperature T2 of the cabin heating circuit, the speed of the heating fan 15 is dynamically adjusted. The greater the difference between the two, the faster the speed of the heating fan 15.

[0099] Afterwards, as the cabin heating starts, the cabin temperature T3 is monitored. When T3 ≥ TS, it can be seen that the cabin heating demand has been met, and at this time, the ice at the hydrogen circulation pump 4, the nitrogen exhaust valve 7 and the drain valve 8 has also been heated and removed (if not, emergency heating is performed, for specific execution, see Figure 5 As shown), heating of the battery stack 27 can thus continue.

[0100] The specific implementation of the heating of the stack 27 is as follows: the bypass valve 20 executes: ports ① and ③ are fully open, and the opening of port ② is 0; the three-way proportional valve 11 executes: the opening of port ② is 0, and ports ③ and ① are fully open; the first heater 22 operates at full power, the second heater 12 operates at full power, the second water pump 13 operates, and the first water pump 18 operates at 30% power to increase the circulation flow of the heat exchange medium. Among them, the second water pump 13 is a relatively low-pressure water pump, and the first water pump 18 is a relatively high-pressure water pump. At this stage, the heat exchange medium flows through the stack 27 by split flow, and at this time, the heaters of the fuel cell circuit and the cabin warm air circuit are still being heated synchronously, so the stack 27 can also achieve rapid heating, thereby improving the cold start speed of the vehicle. In addition, at this stage, since the cabin temperature T3 has just risen to TS, the cabin temperature has basically met the needs of passengers, so the power of the warm air fan 15 can be appropriately reduced or the warm air fan can be temporarily stopped to allow more heat to flow into the stack 27 and heat the stack 27 quickly.

[0101] When the stack temperature T1 reaches the first threshold value T11 (e.g. 10°C), the startup condition is met. At this time, the fuel cell system can be controlled to start, and air and hydrogen can be introduced into the stack 27 to establish the cathode and anode pressures of the system. After the fuel cell system is started, the stack 27 itself begins to generate heat. This stage is an unstable startup stage, so the fuel cell system usually does not output power and heat to the outside.

[0102] During the heating start-up phase of the fuel cell stack 27, the pressure reducing valve 2 and the proportional control valve 3 are dynamically adjusted to ensure that the indication P1 of the pressure sensor 5 remains stable, the operation of the hydrogen circulation pump 4 is maintained, and the pulse opening frequency of the drain valve 8 and the nitrogen exhaust valve 7 are dynamically adjusted synchronously, so that the working state of the fuel cell system gradually stabilizes, and after stabilization, the vehicle's power drive can be intervened.

[0103] In the embodiment of the present application, a waste heat utilization link is also designed, and reference is made to Figure 4 When the stack temperature T1 ≥ T12 (the second threshold value T12 is the stack temperature when the fuel cell system can work stably, usually about 40°C), it means that the stack 27 can work stably, and the fuel cell system can output power to the whole vehicle based on the demand of FCU (Fuel Cell Control Unit, fuel cell system controller), and can output waste heat. At this time, the first heater 22 and the second heater 12 can be turned off, and the second water pump 13 can be turned off at the same time, and only the first water pump 18 is kept working to maintain the medium circulation, and the cabin is heated by the waste heat of the stack 27; or, when T1 < T12, but T1-T3 ≤ the preset value, at this time, since the temperature difference between the stack temperature T1 and the cabin temperature T3 does not exceed the preset value, the low temperature of the cabin will not affect the normal operation of the fuel cell system. Therefore, the first heater 22 and the second heater 12 can also be turned off, and the second water pump 13 can be turned off, and the cabin temperature can be controlled by the waste heat of the stack 27 to reduce energy consumption.

[0104] During the stage of utilizing the waste heat from the fuel cell stack 27 to heat the cabin, the heater fan 15 dynamically adjusts its speed based on the difference between the cabin temperature T3 and the preset cabin temperature TS. During this stage, the heat required for the cabin is provided by the waste heat from the fuel cell stack 27 and transported using a heat exchange medium, with a medium flowing through the anode heating pipe 26 and the return pipe 17.

[0105] Again, in this embodiment, a high-temperature cooling link is also provided to protect the operation of the battery stack 27. When the battery stack temperature T1 ≥ T13 (T13 is the high temperature warning line of the operating temperature of the fuel cell system, and T13 is set to 65°C in this embodiment), it is considered that the heat generation of the battery stack 27 is too high, and the heat dissipation branch needs to intervene for cooling. Specific implementation: The bypass valve 20 dynamically adjusts the opening of ports ① and ② to complete the diversion of the heat exchange medium of the battery stack 27 so that it flows through the radiator 24; the speed of the first water pump 18, the speed of the cooling fan 23, and the opening of the bypass valve 20 are all dynamically adjusted based on T1, and finally the battery stack is maintained in the preset temperature range, that is: 65°C<T1≤80°C.

[0106] based on Figure 1 The thermal management system embodiment shown, Figure 5 A schematic diagram of the leak detection and emergency heating execution process of the anode gas transmission structure in the thermal management process of one embodiment of the present application is shown.

[0107] See also Figure 5 As shown, first, open the pressure reducing valve 2 and the proportional regulating valve 3 to establish the system anode pressure, and the FCU monitors the indication P1 of the pressure sensor 5. When P1 reaches the preset pressure value of the hydrogen pressure required by the anode, the pressure reducing valve 2 and the proportional regulating valve 3 are closed.

[0108] Then, the nitrogen exhaust valve 7 and the water drain valve 8 are opened respectively, and the FCU monitors the decreasing rate of the P1 indication. If the decreasing rate is lower than the calibration value, it is determined that the nitrogen exhaust valve 7 or the water drain valve 8 is frozen.

[0109] In addition, the FCU sends a test operation instruction to the hydrogen circulation pump 4 and receives a speed feedback value of the hydrogen circulation pump 4. If the feedback speed of the hydrogen circulation pump 4 is zero, it is determined that the hydrogen circulation pump 4 is frozen.

[0110] According to whether there is ice, determine whether the anode gas transmission structure is normal. If it is normal, the battery stack 27 can be heated and the fuel cell system can be started. If it is not normal, emergency heating is required. Figure 5 As shown, if there is an icing anomaly, the emergency heating mode is entered, the first heater 22 runs at full power, the second heater 12 runs at full power, and the first water pump runs at 30% power to increase the circulation flow of the heat exchange medium. This process lasts for 60 seconds and then is tested again.

[0111] If the retest result is normal, the stack 27 can be heated and the fuel cell system can be started. If the retest result is still abnormal, the vehicle is judged to be faulty, and it is operated in pure electric mode to find the nearest repair point or wait for repair on the spot. Of course, it is understandable that the emergency heating process can be cyclically performed several times in the above process to determine whether the anode gas transmission structure is really faulty, so as to eliminate the icing problem that can be solved as much as possible.

[0112] based on Figure 1 The thermal management system embodiment shown, Figure 6 A schematic diagram of the execution process of the cabin heating flow based on a non-fuel and electric starting branch in the thermal management process of an embodiment of the present application is shown.

[0113] See also Figure 6 As shown, after determining that the vehicle does not start the fuel-electric system in this stage and only relies on pure electric driving, if the cabin temperature T3 is detected to be less than TS, the cabin is heated by the cabin heating circuit alone. Otherwise, it is determined that there is no need for heating the cabin and the cabin heating circuit is not started.

[0114] When the cabin is heated solely by the cabin heating circuit, the three-way proportional valve 11 is executed: the opening of port ① is 0, and ports ② and ③ are fully open; the second heater 12 is started, the second water pump 13 is running, and the heat exchange medium circulates only in the cabin heating circuit.

[0115] In this stage, the speed of the warm air fan 15 is dynamically adjusted based on the cabin temperature T3 and the actual temperature T2 of the cabin warm air circuit. The greater the difference between the two, the faster the speed of the warm air fan 15.

[0116] After heating to T3 ≥ TS, the cabin heating demand has been met. According to the actual situation, the second heater 12, the second water pump 13 and the warm air fan 15 are dynamically adjusted based on the difference between T3 and TS to perform power reduction or shutdown operations.

[0117] In summary, in the technical solution of the present application, the thermal management system is provided with an anode heating pipeline, which passes through the anode gas delivery structure and connects the heat exchange medium channels of the fuel cell circuit and the cabin heating circuit, so that the anode gas delivery structure can be heated by means of the heat exchange medium in the two circuits to overcome the abnormal hydrogen pumping problem of the fuel cell system caused by system icing during startup. At the same time, since the two heaters of the fuel cell circuit and the cabin heating circuit can work together at the same time, heating is performed for different heating areas (such as the stack, the cabin or the anode gas delivery structure), and a smaller amount of heat exchange medium is used to intervene in the temperature control process, the vehicle's heaters are fully utilized to work together, which greatly improves the cabin heating and the low-temperature cold start speed of the fuel cell system, and improves the driving experience of the fuel cell vehicle.

[0118] At the same time, the embodiment of the present application uses the anode heating pipeline to achieve the connected circulation of the heat exchange medium, which is also beneficial to reduce the amount of heat exchange medium used, simplify the vehicle's heat exchange medium circulation pipeline design, and is beneficial to achieve structural optimization of fuel cell vehicles.

[0119] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A thermal management system for a fuel cell vehicle, characterized in that: The thermal management system comprises: a fuel cell system and a cabin heating circuit, wherein the fuel cell system comprises a fuel cell circuit and an anode heating pipe (26); The fuel cell circuit is used to heat or cool a fuel cell stack (27) of a fuel cell system, and comprises a first heater (22); The cabin heating circuit is used to heat the cabin and comprises a second heater (12); The anode heating pipe (26) passes through the anode gas supply structure of the fuel cell system and connects the fuel cell circuit and the cabin heating circuit, so that the heat exchange medium in the two circuits can be exchanged and circulated with each other, so that the two circuits can heat the heat exchange medium at the same time when the vehicle is started, and jointly provide heat for the fuel cell stack (27), the cabin and / or the anode gas supply structure through the heat exchange medium.

2. The thermal management system of a fuel cell vehicle according to claim 1, characterized in that: The anode gas transmission structure comprises: a hydrogen circulation pump (4) and an anode gas-liquid separator (6), the hydrogen circulation pump (4) is connected to the anode hydrogen inlet of the fuel cell stack (27), the anode gas-liquid separator (6) is connected to the anode hydrogen outlet of the fuel cell stack (27), the anode gas-liquid separator (6) comprises a nitrogen exhaust valve (7) and a water exhaust valve (8), a water exchange water jacket is arranged on the outer side of the anode gas-liquid separator (6), the anode heating pipe (26) passes through the heat exchange medium channel of the hydrogen circulation pump (4) and the water exchange water jacket, the inlet of the anode heating pipe (26) is connected to the fuel cell circuit, and the outlet of the anode heating pipe (26) is connected to the cabin heating circuit; A pressure sensor (5) is provided on the outlet side of the hydrogen circulation pump (4), and an air intake valve is provided on the inlet side of the hydrogen circulation pump (4).

3. The thermal management system of a fuel cell vehicle according to claim 2, characterized in that: The fuel cell circuit comprises: a first water pump (18), a bypass valve (20), a deionizer (21), the first heater (22), a radiator (24), a cooling fan (23) and an overflow kettle (25); The outlet of the first water pump (18) is respectively connected to the medium inlet of the battery stack (27) and the inlet of the anode heating pipe (26); the medium outlet of the battery stack (27) is connected to the first end of the bypass valve (20); the second end of the bypass valve (20) is connected to the inlet of the first water pump (18) via the radiator (24); the third end of the bypass valve (20) is connected to the inlet of the first water pump (18) via the deionizer (21) and the first heater (22); the cooling fan (23) is arranged at the radiator (24); the inlet of the overflow pot (25) is connected to the outlet of the radiator (24); and the outlet of the overflow pot (25) is connected to the inlet of the first water pump (18); a first temperature sensor (19) is arranged on the medium outlet side of the battery stack (27).

4. The thermal management system of a fuel cell vehicle according to claim 3, characterized in that: The cabin heating circuit comprises: a three-way proportional valve (11), the second heater (12), a second water pump (13), a heating core (16) and a heating fan (15); The first end of the three-way proportional valve (11) is connected to the outlet of the anode heating pipe (26), the second end of the three-way proportional valve (11) is connected to the outlet of the heater core (16), the third end of the three-way proportional valve (11) is connected to the inlet of the heater core (16) via the second heater (12) and the second water pump (13), and the outlet of the heater core (16) is connected to the inlet of the deionizer (21) of the fuel cell circuit via a return pipe (17); A second temperature sensor (14) is provided on the inlet side of the warm air core (16).

5. A thermal management method for a fuel cell vehicle, applied to the thermal management system of a fuel cell vehicle according to any one of claims 1 to 4, characterized in that: The method comprises: When the vehicle is started, the enabling state of the fuel cell system and the stack temperature T1 are detected to control the fuel cell circuit and the cabin heating circuit according to the detection results; If the fuel cell system is in an enabled state and the stack temperature T1 is lower than the lowest temperature T0, it is determined that this is a cold start, and the first heater (22) of the fuel cell circuit and the second heater (12) of the cabin heating circuit are started, and the heat exchange medium is controlled to circulate between the two circuits through the anode heating pipeline (26) and does not flow through the stack (27) of the fuel cell system, so as to heat the cabin and the anode gas transmission structure; Monitoring the cabin temperature T3, when the cabin temperature T3 rises to a preset cabin temperature TS, performing a leak detection on the anode gas supply structure to determine whether the anode gas supply structure is normal; If the anode gas supply structure is normal, the heat exchange medium is controlled to flow through the fuel cell stack (27) of the fuel cell system to heat the fuel cell stack (27), and when the stack temperature T1 rises to a first threshold value T11, the fuel cell system is started.

6. The thermal management method for a fuel cell vehicle according to claim 5, characterized in that: The anode gas transmission structure comprises a hydrogen circulation pump (4) and an anode gas-liquid separator (6), and the performing of leak detection on the anode gas transmission structure to determine whether the anode gas transmission structure is normal comprises: Opening the air intake valve on the air intake side of the hydrogen circulation pump (4) to make the anode gas pressure of the fuel cell system reach a preset air pressure value, and then closing the air intake valve; then opening the nitrogen exhaust valve (7) and the water drain valve (8) of the anode gas-liquid separator (6) respectively, and obtaining the corresponding air pressure drop rate; if the air pressure drop rate is lower than the calibration value, it is judged that the nitrogen exhaust valve (7) or the water drain valve (8) has an abnormal icing; otherwise, it is judged to be normal; A test run instruction is issued to the hydrogen circulation pump (4), and a speed feedback value of the hydrogen circulation pump (4) is obtained. If the speed feedback value is zero, it is determined that the hydrogen circulation pump (4) has an icing abnormality; otherwise, it is determined to be normal.

7. The thermal management method for a fuel cell vehicle according to claim 6, characterized in that: After performing a leak detection on the anode gas transmission structure, if it is determined that there is an abnormality, emergency heating is started; Controlling the first heater (22) and the second heater (12) to operate at full power, while increasing the circulation flow of the heat exchange medium, and after a preset time, performing leak detection on the anode gas transmission structure again; If the result of the re-detection is normal, the heat exchange medium is controlled to flow through the fuel cell stack (27) to heat the fuel cell stack (27), and when the fuel cell stack temperature T1 rises to a first threshold value T11, the fuel cell system is started; If the abnormality is still found after the re-detection, an alarm message will be issued to indicate vehicle failure.

8. The thermal management method for a fuel cell vehicle according to claim 5, characterized in that: When the vehicle is started, If it is detected that the fuel cell system is in an enabled state, but the stack temperature T1 is not lower than the minimum preset temperature T0, it is determined that this is a thermal engine start, and the fuel cell system is started normally; If it is detected that the fuel cell system is in a disabled state and the cabin temperature T3 is lower than a preset cabin temperature TS, the second heater (12) of the cabin heating circuit is started separately to heat the cabin independently through the cabin heating circuit.

9. The thermal management method for a fuel cell vehicle according to claim 5, characterized in that: After the vehicle is started, when the cabin temperature T3 is less than the preset cabin temperature TS, the stack temperature T1 is detected; if it is detected that the stack temperature T1 satisfies the waste heat utilization condition, the heat exchange medium is controlled to circulate between the fuel cell circuit and the cabin heating circuit through the anode heating pipe (26), and the cabin is heated by the waste heat of the stack (27); otherwise, the second heater (12) of the cabin heating circuit is turned on, and the cabin is heated by the second heater (12) alone, and the stack temperature T1 is monitored in real time; If it is monitored that the temperature T1 of the fuel cell stack rises to meet the waste heat utilization condition, the heat exchange medium is controlled to circulate between the fuel cell circuit and the cabin heating circuit through the anode heating pipe (26), and the second heater (12) is turned off, so that the waste heat of the fuel cell stack (27) is used to heat the cabin; The waste heat utilization condition includes: the stack temperature T1 reaches the second threshold value T12, or, although the stack temperature T1 does not reach the second threshold value T12, the difference between the stack temperature T1 and the cabin temperature T3 is less than a preset value.

10. The thermal management method for a fuel cell vehicle according to any one of claims 5 to 9, characterized in that: When the stack temperature T1 rises to a third threshold value T13, the cooling function of the fuel cell circuit is activated to cool the stack (27) and control the stack temperature T1 to remain within a preset temperature range.

Images