Cooling system for fuel cell, control method and vehicle

Abstract

The invention provides a cooling system for a fuel cell, a control method and a vehicle, and the cooling system for the fuel cell comprises a cooling flow channel which is formed on a shell of the fuel cell; the heat dissipation assembly comprises a high-temperature radiator and a heat dissipation fan, the heat dissipation fan is arranged on the air outlet side of the high-temperature radiator, the high-temperature radiator and the cooling flow channel are connected in series to form a heat exchange loop, the heat exchange loop is filled with a cooling medium, and the cooling medium has a first phase change state and a second phase change state; and the water pump is arranged between the high-temperature radiator and the cooling flow channel, and the water pump communicates with the heat exchange loop. According to the cooling system in the scheme, the two-phase-state cooling medium is used for absorbing and releasing latent heat, efficient heat dissipation is achieved, the scheme that the heat dissipation effect is improved by increasing a radiator and a heat dissipation fan in the prior art is replaced, and the technical problems that in the prior art, a cooling system of a fuel cell is large in size, high in cost, poor in reliability and high in energy consumption are solved.

Description

Technical Field

[0001] This invention relates to the technical field of cooling systems, and more specifically, to a cooling system, control method, and vehicle for fuel cells. Background Technology

[0002] The thermal management systems of new energy commercial vehicles generally adopt a pure liquid-phase cooling scheme. Core components such as fuel cells, motors, and electronic controls are cooled through independent water-cooling circuits. The operating temperature range of fuel cells is 80~90℃, which is much lower than the operating temperature range of traditional engines (110~120℃). However, the heat dissipation requirement per unit power of a fuel cell can be twice that of an engine. This forces existing systems to rely on multiple large radiators and multiple sets of high-pressure or low-pressure fans operating in parallel to meet the heat dissipation requirements under high heat flux density. This approach not only results in a large system size and high cost, but also significantly reduces overall reliability due to complex piping and numerous interfaces. At the same time, the continuous high-speed operation of the fans leads to additional energy consumption, which seriously affects the vehicle's driving range and makes it difficult to meet the future development needs of high-power, long-range fuel cell commercial vehicles.

[0003] There is currently no effective solution to the technical problems of large size, high cost, poor reliability and high energy consumption of the cooling system of fuel cells in existing technologies. Summary of the Invention

[0004] The main objective of this invention is to provide a cooling system, control method, and vehicle for fuel cells, in order to solve the technical problems of large size, high cost, poor reliability, and high energy consumption of existing fuel cell cooling systems.

[0005] To achieve the above objectives, according to one aspect of the present invention, a cooling system for a fuel cell is provided, comprising: a cooling channel formed on the housing of the fuel cell; a heat dissipation assembly including a high-temperature radiator and a cooling fan, the cooling fan being disposed on the air outlet side of the high-temperature radiator, the high-temperature radiator and the cooling channel being connected in series to form a heat exchange circuit, the heat exchange circuit being filled with a cooling medium having a first phase change state and a second phase change state; and a water pump disposed between the high-temperature radiator and the cooling channel, the water pump being connected to the heat exchange circuit.

[0006] Furthermore, an expansion tank is provided on the heat exchange circuit. The expansion tank is located between the high-temperature radiator and the water pump. The liquid inlet of the expansion tank is connected to the liquid outlet of the high-temperature radiator, and the liquid outlet of the expansion tank is connected to the liquid inlet of the water pump.

[0007] Furthermore, a gas-liquid separator is provided on the heat exchange circuit. The gas-liquid separator is located between the expansion tank and the water pump. The inlet of the gas-liquid separator is connected to the outlet of the expansion tank, and the outlet of the gas-liquid separator is connected to the inlet of the water pump.

[0008] Furthermore, the gas-liquid separator is located at the exhaust port, which is connected to the expansion tank via a return pipe.

[0009] Furthermore, the cooling system also includes: a heater core, the inlet of which is connected to the outlet of the cooling channel, and the outlet of which is connected to the inlet of the cooling channel.

[0010] According to another aspect of the present invention, a control method for a cooling system for a fuel cell is provided. The cooling system for the fuel cell is the aforementioned cooling system for a fuel cell. The control method includes: acquiring the inlet temperature of a high-temperature radiator and a thermal management mode, wherein the thermal management mode includes a heating mode and a non-heating mode; generating a first control strategy set based on the high-temperature radiator inlet temperature and the thermal management mode, wherein the first control strategy set includes at least one of the following: a strategy for regulating the speed of the cooling fan, and a strategy for regulating the on / off state of the cooling channel and the heating core.

[0011] Furthermore, a first control strategy set is generated based on the high-temperature radiator inlet temperature and thermal management mode, including: when the high-temperature radiator inlet temperature is greater than the preset temperature, a first target strategy is generated in the first control strategy set, wherein the first target strategy is used to control the cooling fan to turn on and adjust the speed of the cooling fan according to the high-temperature radiator inlet temperature.

[0012] Furthermore, a first control strategy set is generated based on the high-temperature radiator inlet temperature and thermal management mode, including: when the thermal management mode is heating mode, a second target strategy is generated in the first control strategy set, wherein the second target strategy is used to control the on / off of the cooling channel and the heating core.

[0013] Furthermore, the control method also includes: acquiring a first operating state of the cooling fan and a second operating state of the water pump; generating a second control strategy set based on the first and second operating states, wherein the second control strategy set includes at least one of the following: a strategy to instruct the fuel cell to stop operating, and a strategy to instruct the fuel cell to continue operating.

[0014] According to another aspect of the present invention, a vehicle is provided, the vehicle including a fuel cell, the fuel cell including the aforementioned cooling system for fuel cells.

[0015] The technical solution of this invention involves a cooling channel formed on the fuel cell casing connected in series with a high-temperature radiator to form a heat exchange circuit. The heat exchange circuit is filled with a two-phase cooling medium. A water pump is installed on the heat exchange circuit to adjust the flow rate of the cooling medium according to heat dissipation requirements. The cooling medium absorbs latent heat at the fuel cell heat source through a phase change and releases latent heat at the high-temperature radiator through a phase change. In other words, the cooling medium carries away a large amount of latent heat through phase change during the heat exchange process, thereby achieving efficient heat dissipation and increasing the heat dissipation capacity per unit flow rate. Only a single radiator is needed to achieve the required heat dissipation effect for the system. The cooling system in the above solution utilizes a two-phase cooling medium for latent heat absorption and release, achieving efficient heat dissipation. This replaces the existing technology's approach of increasing the size of the radiator and the cooling fan to improve heat dissipation, solving the technical problems of large size, high cost, poor reliability, and high energy consumption in existing fuel cell cooling systems. Attached Figure Description

[0016] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0017] Figure 1 A schematic diagram of a cooling system for a fuel cell according to a first embodiment of the present invention is shown;

[0018] Figure 2 A schematic diagram of a cooling system for a fuel cell according to a second embodiment of the present invention is shown;

[0019] Figure 3 A control flowchart of the cooling system in a third embodiment of the present invention is shown;

[0020] Figure 4 A control flowchart of the cooling system in the fourth embodiment of the present invention is shown;

[0021] Figure 5 A control flowchart of the cooling system in a fifth embodiment of the present invention is shown.

[0022] The above figures include the following reference numerals:

[0023] 1. Fuel cells;

[0024] 2. High-temperature radiator;

[0025] 3. Cooling fan;

[0026] 4. Water pump;

[0027] 5. Expansion box;

[0028] 6. Gas-liquid separator;

[0029] 61. Return pipe;

[0030] 7. Warm air core;

[0031] 8. First pipeline;

[0032] 9. Second pipeline. Detailed Implementation

[0033] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0034] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0035] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0036] Exemplary embodiments according to this application will now be described in more detail with reference to the accompanying drawings. However, these exemplary embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein. It should be understood that these embodiments are provided so that the disclosure of this application is thorough and complete, and that the concept of these exemplary embodiments is fully conveyed to those skilled in the art. In the drawings, for clarity, the thickness of layers and regions may be exaggerated, and the same reference numerals are used to denote the same devices, and therefore their description will be omitted.

[0037] Combination Figures 1 to 2 As shown, according to a specific embodiment of this application, a cooling system for a fuel cell is provided.

[0038] Specifically, the cooling system for fuel cell 1 includes: a cooling channel, a heat dissipation assembly, and a water pump 4. The cooling channel is formed on the casing of fuel cell 1. The heat dissipation assembly includes a high-temperature radiator 2 and a cooling fan 3. The cooling fan 3 is located on the air outlet side of the high-temperature radiator 2. The high-temperature radiator 2 and the cooling channel are connected in series to form a heat exchange loop. The heat exchange loop is filled with a cooling medium having a first phase change state and a second phase change state. The water pump 4 is located between the high-temperature radiator 2 and the cooling channel, and the water pump 4 is connected to the heat exchange loop.

[0039] Applying the technical solution of this invention, a cooling channel formed on the housing of fuel cell 1 is connected in series with a high-temperature radiator 2 to form a heat exchange circuit. The heat exchange circuit is filled with a two-phase cooling medium. A water pump 4 is installed on the heat exchange circuit to adjust the flow rate of the cooling medium according to the heat dissipation requirements. The cooling medium absorbs heat and undergoes a phase change at the heat source of fuel cell 1 to absorb latent heat, and releases heat and undergoes a phase change at the high-temperature radiator 2 to release latent heat. That is, the cooling medium carries away a large amount of latent heat through phase change during the heat exchange process, thereby achieving efficient heat dissipation and improving the heat dissipation capacity per unit flow rate. Only a single radiator is needed to achieve the required heat dissipation effect of the system. The cooling system in the above solution utilizes a two-phase cooling medium for latent heat absorption and release to achieve efficient heat dissipation, replacing the solution in the prior art that improves the heat dissipation effect by increasing the size of the radiator and the cooling fan 3. This solves the technical problems of large size, high cost, poor reliability, and high energy consumption of the cooling system of fuel cell 1 in the prior art.

[0040] It should be noted that the cooling medium is a low-boiling-point alcohol coolant, such as ethylene glycol or propylene glycol. The cooling medium's condensation point can be adjusted by adding additives. Since the water temperature of fuel cell 1 is generally below 85°C, the cooling medium used in this application is a coolant with a boiling point of 75°C, which undergoes a phase change between liquid and gaseous states.

[0041] Furthermore, an expansion tank 5 is provided on the heat exchange circuit. The expansion tank 5 is located between the high-temperature radiator 2 and the water pump 4. The liquid inlet of the expansion tank 5 is connected to the liquid outlet of the high-temperature radiator 2, and the liquid outlet of the expansion tank 5 is connected to the liquid inlet of the water pump 4.

[0042] It should be noted that after the cooling medium absorbs heat and vaporizes at the fuel cell 1, it enters the high-temperature radiator 2 in the form of a gas-liquid mixture. Although the high-temperature radiator 2 can achieve the condensation and liquefaction of most of the gaseous medium under the forced cooling of the cooling fan 3, due to factors such as thermal inertia, airflow fluctuations, and uneven local heat exchange, a small amount of incompletely condensed bubbles or vapors will inevitably remain at the outlet of the high-temperature radiator 2. If such a gas-liquid mixture directly enters the impeller area of ​​the water pump 4, it will cause severe cavitation. The bubbles will collapse instantly in the high-pressure area, generating micro-jet and shock waves, leading to pitting corrosion on the impeller surface, material fatigue, and increased vibration. Ultimately, this will cause the water pump 4 to fail to seal, its lifespan to be drastically reduced, and may even cause the cooling system to collapse, threatening the safe operation of the entire vehicle.

[0043] In the embodiments of this application, an expansion tank 5 is provided between the high-temperature radiator 2 and the water pump 4. The expansion tank 5 is filled with a low-temperature cooling medium. The gas-liquid mixture flowing in from the high-temperature radiator 2 is sufficiently delayed and stationary in the relatively static, low-temperature liquid phase environment. The residual bubbles re-condense into liquid under the action of heat conduction and pressure in the liquid phase, improving the phase purity of the cooling medium and thus preventing the gaseous medium from entering the water pump 4. At the same time, the expansion tank 5 can act as a volume compensator for the system, absorbing loop pressure fluctuations caused by temperature fluctuations or power surges, buffering volume changes caused by thermal expansion and contraction, preventing system overpressure or negative pressure, thereby improving control accuracy and dynamic response capability.

[0044] Furthermore, a gas-liquid separator 6 is provided on the heat exchange circuit. The gas-liquid separator 6 is located between the expansion tank 5 and the water pump 4. The inlet of the gas-liquid separator 6 is connected to the outlet of the expansion tank 5, and the outlet of the gas-liquid separator 6 is connected to the inlet of the water pump 4.

[0045] It should be noted that although expansion tank 5 has achieved secondary condensation of most gaseous media under static conditions through heat exchange and pressure control, under actual operating conditions, such as power transient fluctuations, local overheating of radiators, pipeline vibration disturbances, or changes in coolant circulation flow rate, there may still be micron-sized bubbles or trace amounts of vapor that fail to completely liquefy and enter the outlet of expansion tank 5 with the liquid flow. Although the proportion is extremely low, it is enough to cause local vaporization at the low-pressure suction port of the high-speed rotating water pump 4, forming micro-cavitation. Long-term accumulation will cause pitting corrosion on the impeller surface, bearing wear, increased noise, and even seal failure, ultimately leading to the collapse of the cooling system.

[0046] In the embodiments of this application, a gas-liquid separator 6 is provided between the expansion tank 5 and the water pump 4. The gas-liquid separator 6 can be designed with physical structures such as gravity sedimentation, centrifugal cyclone, or baffle filtration, which can efficiently separate trace bubbles remaining in the liquid phase within milliseconds. The gas-liquid separator 6 enables the system to have fault tolerance for extreme operating conditions. For example, during the low-temperature start-up phase, the coolant has not yet fully reached phase change equilibrium, or when the environmental pressure decreases in high-altitude areas, the risk of gas phase precipitation increases. At this time, the static condensation capacity of the expansion tank 5 may be insufficient, but the gas-liquid separator 6 can still actively capture and process the escaping gas, ensuring that the water pump 4 is always within the safe operating boundary, thereby improving the system's adaptability and robustness under complex operating conditions.

[0047] Furthermore, the gas-liquid separator 6 is located at the exhaust port, and the exhaust port is connected to the expansion tank 5 through the return pipe 61.

[0048] In the embodiments of this application, the exhaust port of the gas-liquid separator 6 is connected to the expansion tank 5 through the return pipe 61. The gaseous medium separated by the gas-liquid separator 6 flows into the expansion tank 5 through the return pipe 61. The gaseous medium is re-condensed into liquid in the expansion tank 5 and re-enters the heat exchange circuit, thus realizing the recycling of the cooling medium.

[0049] Furthermore, the cooling system also includes: a heater core 7, the inlet of which is connected to the outlet of the cooling channel, and the outlet of which is connected to the inlet of the cooling channel.

[0050] It should be noted that the temperature of the gas-liquid mixture cooling medium flowing out of the cooling channel outlet is relatively high, and its enthalpy value is much higher than that of the liquid coolant at the outlet of a traditional liquid cooling system.

[0051] In the embodiments of this application, the inlet of the heater core 7 is connected to the outlet of the cooling channel, and the outlet of the heater core 7 is connected to the inlet of the cooling channel. That is, the high-temperature cooling medium flowing out of the cooling channel outlet can be introduced into the heater core 7, where condensation and heat release occur, thereby realizing the recovery and utilization of waste heat from the fuel cell 1.

[0052] Specifically, the inlet of the heater core 7 is connected to the outlet of the cooling channel, and the outlet of the heater core 7 is connected to the inlet of the cooling channel. That is, the heater core 7 and the cooling channel are connected in series to form a waste heat recovery circuit. A second control valve is provided on the waste heat recovery circuit, and the second control valve controls the opening and closing of the waste heat recovery circuit.

[0053] Preferably, the warm air core 7 and the cooling channel are connected in series through the second pipe 9 to form a waste heat recovery circuit. A heater is connected in series in the waste heat recovery circuit to provide additional heat energy to the waste heat recovery circuit to supplement the heat energy of the waste heat recovery circuit.

[0054] In one exemplary embodiment of this application, such as Figure 1 As shown, the cooling system for fuel cell 1 includes: a cooling channel, a heat dissipation assembly, a water pump 4, an expansion tank 5, and a gas-liquid separator 6. The cooling channel is formed on the casing of fuel cell 1. The heat dissipation assembly includes a high-temperature radiator 2 and a cooling fan 3. The cooling fan 3 is located on the air outlet side of the high-temperature radiator 2, and the speed of the cooling fan 3 is adjusted to dissipate heat from the high-temperature radiator 2. The cooling channel, high-temperature radiator 2, expansion tank 5, gas-liquid separator 6, and water pump 4 are connected in series through a first pipeline 8 to form a heat exchange circuit. A first control valve is provided on the heat exchange circuit to control the opening and closing of the heat exchange circuit. The exhaust port of the gas-liquid separator 6 is connected to the expansion tank 5 through a return pipeline 61.

[0055] In another exemplary embodiment of this application, such as Figure 2 As shown, the cooling system for fuel cell 1 includes: a cooling channel, a heat dissipation assembly, a water pump 4, an expansion tank 5, a gas-liquid separator 6, and a heater core 7. The cooling channel is formed on the casing of fuel cell 1. The heat dissipation assembly includes a high-temperature radiator 2 and a cooling fan 3. The cooling fan 3 is located on the air outlet side of the high-temperature radiator 2, and the speed of the cooling fan 3 is adjusted to dissipate heat from the high-temperature radiator 2. The cooling channel, high-temperature radiator 2, expansion tank 5, gas-liquid separator 6, and water pump 4 are connected in series through a first pipeline 8 to form a heat exchange circuit. A first control valve is provided on the heat exchange circuit to control the opening and closing of the heat exchange circuit. The exhaust port of the gas-liquid separator 6 is connected to the expansion tank 5 through a return pipeline 61. The inlet of the heater core 7 is connected to the outlet of the cooling channel through the second pipe 9, and the outlet of the heater core 7 is connected to the inlet of the cooling channel through the second pipe 9. That is, the heater core 7 and the cooling channel are connected in series to form a waste heat recovery circuit. A second control valve is provided on the waste heat recovery circuit, which controls the opening and closing of the waste heat recovery circuit.

[0056] In another specific embodiment of this application, a control method for a cooling system for a fuel cell is provided. The cooling system for the fuel cell is the same as the cooling system for the fuel cell described in the above embodiments, such as... Figure 3 As shown, the control method includes the following steps:

[0057] Step S1: Obtain the inlet temperature of the high-temperature radiator and the thermal management mode, wherein the thermal management mode includes: heating mode and non-heating mode.

[0058] Specifically, a temperature sensor is installed at the inlet of the high-temperature radiator. The temperature sensor is connected to a thermal management controller, which receives the inlet temperature feedback from the temperature sensor. Based on the driver's active input, the control module obtains instructions on the thermal management mode through the vehicle's human-machine interface. For example, when the driver manually turns on the "heating" or "defrosting" setting on the air conditioning panel, or selects options such as "winter mode" or "comfort heating" through voice commands or the central control screen, the vehicle control system sends a clear heating mode signal to the thermal management controller (TMC).

[0059] Step S2: Generate a first control strategy set based on the inlet temperature of the high-temperature radiator and the thermal management mode. The first control strategy set includes at least one of the following: a strategy for regulating the speed of the cooling fan, and a strategy for regulating the on / off state of the cooling channel and the heating core.

[0060] In the embodiments of this application, the speed of the cooling fan is adjusted based on the inlet temperature of the high-temperature radiator and the thermal management mode to fully condense the cooling medium in the heat exchange circuit, avoid the presence of gaseous medium in the cooling medium in front of the water pump, and adjust the connection and disconnection between the orifice cooling channel and the warm air core to realize the waste heat recovery of the fuel cell.

[0061] Furthermore, a first set of control strategies is generated based on the high-temperature radiator inlet temperature and thermal management mode, such as... Figure 4 As shown, it includes the following steps:

[0062] Step S21: When the inlet temperature of the high-temperature radiator is greater than the preset temperature, a first target strategy is generated in the first control strategy set. The first target strategy is used to control the cooling fan to turn on and adjust the speed of the cooling fan according to the inlet temperature of the high-temperature radiator.

[0063] In the embodiments of this application, the speed of the cooling fan is adjusted according to the inlet temperature of the high-temperature radiator to avoid insufficient condensation of the cooling medium at the front end of the water pump and to avoid energy waste caused by excessive cooling of the cooling medium at the rear end of the water pump.

[0064] For example, when the inlet temperature T of the high-temperature radiator is greater than the first preset temperature (e.g., T > 73°C, which is higher than the phase change boiling point of the cooling medium), the system determines that the coolant has vaporized in large quantities and the high-temperature radiator needs to undertake a high-intensity condensation task. The cooling fan is then started and runs at high speed to ensure that the gaseous coolant is rapidly liquefied at the front end of the high-temperature radiator, preventing uncondensed gas from entering the water pump and thus avoiding the risk of water pump cavitation.

[0065] For example, when the inlet temperature of the high-temperature radiator is less than or equal to the first preset temperature and greater than the second preset temperature (e.g., 66℃ < T ≤ 73℃), the system determines that the cooling medium flowing out of the high-temperature radiator outlet is pure liquid, starts the cooling fan and runs it at low speed, and compensates for the insufficiency of ambient air cooling.

[0066] For example, when the inlet temperature of the high-temperature radiator is less than or equal to the second preset temperature (e.g., T≤66℃), the system determines that the system heat load is insufficient, shuts down the cooling fan, and avoids excessive heat dissipation that could lead to a drop in system pressure and a reduction in vaporization efficiency.

[0067] Furthermore, a first set of control strategies is generated based on the high-temperature radiator inlet temperature and thermal management mode, such as... Figure 4 As shown, it includes the following steps:

[0068] Step S22: When the thermal management mode is heating mode, generate a second target strategy in the first control strategy set, wherein the second target strategy is used to control the on / off state of the cooling channel and the heating core.

[0069] Specifically, the thermal management controller controls the opening and closing of the second control valve on the waste heat recovery loop according to the thermal management mode.

[0070] In the embodiments of this application, the on / off state of the cooling channel and the heating core is controlled according to the thermal management mode. After the cooling medium exchanges heat with the fuel cell, it is in a gas-liquid mixed state, and its enthalpy value is much higher than that of the liquid coolant at the outlet of the traditional liquid cooling system. The cooling medium in this gas-liquid mixed state condenses and releases heat in the heating core, realizing the recovery and utilization of fuel cell waste heat.

[0071] Furthermore, when the thermal management mode is heating mode, the second target strategy generated in the first control strategy set also includes: obtaining the outlet temperature of the heating core; and controlling the fan air volume of the heating core and the on / off state of the cooling channel and the heating core based on the outlet temperature of the heating core.

[0072] For example, when the outlet temperature of the heater core is higher than the first temperature (e.g., 70°C), it indicates that the heat energy has not been fully absorbed, and the system automatically increases the air volume of the heater fan to improve the heat exchange efficiency.

[0073] For example, if the outlet temperature of the heater core is lower than (e.g., 55°C), it indicates that the heat source is insufficient or the demand for heating is too high. The connection between the cooling channel and the heater core can be disconnected, and the heater core can use other heat sources for heat exchange or heating.

[0074] Furthermore, such as Figure 5 As shown, the control method also includes the following control steps:

[0075] Step S3: Obtain the first operating state of the cooling fan and the second operating state of the water pump.

[0076] Step S4: Generate a second control strategy set based on the first operating state and the second operating state, wherein the second control strategy set includes at least one of the following: a strategy to instruct the fuel cell to stop working, and a strategy to instruct the fuel cell to continue working.

[0077] In the embodiments of this application, the operating state of the fuel cell is adjusted according to the operating state of the cooling fan and the water pump to avoid continuous heating of the cooling medium liquid, which would lead to high system pressure and thus avoid safety accidents.

[0078] For example, if the cooling fan is "stopped" or "speed is below the threshold (e.g., actual speed is less than 20% of rated speed)" and the water pump current is abnormal (e.g., current fluctuation is greater than 15%) or there is no speed signal, the system determines that there is a double cooling failure, immediately triggers the command to stop the fuel cell, cuts off the hydrogen supply and the stack load, and enters the safe shutdown mode.

[0079] For example, if the cooling fan is running normally but the water pump has no output, the system will determine that the cycle is interrupted. Even if the radiator temperature is still within a controllable range, the system will immediately shut down to prevent air bubbles from accumulating in the system and forming an airlock.

[0080] For example, if the fan fails but the water pump is working normally and the inlet temperature of the high-temperature radiator is stable below the rated temperature (e.g., 70°C), the system can determine that it is a "single point of failure with remaining capacity", allowing the fuel cell to continue operating in reduced power mode. At the same time, it issues a warning to the driver: "Attention: Cooling fan is abnormal, please repair as soon as possible", thus achieving safety priority and flexible degradation.

[0081] Furthermore, the system can incorporate a fault duration threshold and a memory of historical fault modes.

[0082] For example, if the cooling fan briefly jitters (e.g., for 2 seconds) and then resumes, the system does not trigger a shutdown; it is simply recorded as a "transient disturbance".

[0083] For example, if the cooling fan stops spinning for more than 5 seconds, it is considered a "substantial fault" and a shutdown is performed.

[0084] For example, if the same water pump experiences current fluctuations three times within 30 days, the system will automatically mark the "water pump health" as "critical" and suggest maintenance in advance, thus realizing the evolution from "passive protection" to "active prediction".

[0085] Furthermore, the control method for the cooling system of fuel cells can also predict the trend of heat load changes in the fuel cell within a preset time (e.g., within 30 seconds) based on the current vehicle speed, gradient, air conditioning set temperature, and historical operating data. If the predicted load will increase sharply (e.g., accelerating uphill), the fan speed will be increased in advance to reserve sufficient heat dissipation margin for the fuel cell; if the predicted load will decrease (e.g., entering a tunnel), the heater core will be turned on in advance to recover the excess heat energy, achieving preheating and waste heat recovery.

[0086] According to another specific embodiment of this application, a vehicle is provided, the vehicle including a fuel cell, the fuel cell including the fuel cell cooling system of the above embodiments.

[0087] Specifically, the cooling system includes a cooling channel, a heat dissipation assembly, and a water pump 4. The cooling channel is formed on the casing of the fuel cell 1. The heat dissipation assembly includes a high-temperature radiator 2 and a cooling fan 3. The cooling fan 3 is located on the air outlet side of the high-temperature radiator 2. The high-temperature radiator 2 and the cooling channel are connected in series to form a heat exchange loop. The heat exchange loop is filled with a cooling medium having a first phase change state and a second phase change state. The water pump 4 is located between the high-temperature radiator 2 and the cooling channel, and the water pump 4 is connected to the heat exchange loop.

[0088] A cooling channel formed on the casing of fuel cell 1 is connected in series with high-temperature radiator 2 to form a heat exchange circuit. The heat exchange circuit is filled with a two-phase cooling medium. A water pump 4 is installed on the heat exchange circuit to adjust the flow rate of the cooling medium according to the heat dissipation requirements. The cooling medium absorbs heat and undergoes a phase change at the heat source of fuel cell 1 to absorb latent heat, and releases heat and undergoes a phase change at high-temperature radiator 2 to release latent heat. That is, the cooling medium removes a large amount of latent heat through phase change during the heat exchange process, thereby achieving efficient heat dissipation and improving the heat dissipation capacity per unit flow rate. Only a single radiator is needed to achieve the required heat dissipation effect of the system. The cooling system in the above scheme uses a two-phase cooling medium to absorb and release latent heat to achieve efficient heat dissipation, replacing the solution in the prior art that improves the heat dissipation effect by increasing the size of the radiator and the cooling fan 3. This solves the technical problems of large size, high cost, poor reliability and high energy consumption of the cooling system of fuel cell 1 in the prior art.

[0089] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0090] In addition to the above, it should be noted that the terms "one embodiment," "another embodiment," and "embodiment" used in this specification refer to specific features, structures, or characteristics described in connection with that embodiment, which are included in at least one embodiment described in the general description of this application. The appearance of the same expression in multiple places in the specification does not necessarily refer to the same embodiment. Furthermore, when a specific feature, structure, or characteristic is described in connection with any embodiment, the intention is to suggest that implementing such a feature, structure, or characteristic in conjunction with other embodiments also falls within the scope of this invention.

[0091] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0092] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A cooling system for a fuel cell, characterized in that, include: Cooling channels are formed on the housing of the fuel cell (1); The heat dissipation assembly includes a high-temperature radiator (2) and a cooling fan (3). The cooling fan (3) is located on the air outlet side of the high-temperature radiator (2). The high-temperature radiator (2) is connected in series with the cooling channel to form a heat exchange circuit. The heat exchange circuit is filled with a cooling medium, which has a first phase change state and a second phase change state. Water pump (4) is located between the high-temperature radiator (2) and the cooling channel, and the water pump (4) is connected to the heat exchange circuit.

2. The cooling system for fuel cells according to claim 1, characterized in that, An expansion tank (5) is provided on the heat exchange circuit. The expansion tank (5) is located between the high-temperature radiator (2) and the water pump (4). The liquid inlet of the expansion tank (5) is connected to the liquid outlet of the high-temperature radiator (2), and the liquid outlet of the expansion tank (5) is connected to the liquid inlet of the water pump (4).

3. The cooling system for fuel cells according to claim 2, characterized in that, A gas-liquid separator (6) is provided on the heat exchange circuit. The gas-liquid separator (6) is located between the expansion tank (5) and the water pump (4). The inlet of the gas-liquid separator (6) is connected to the outlet of the expansion tank (5), and the outlet of the gas-liquid separator (6) is connected to the inlet of the water pump (4).

4. The cooling system for fuel cells according to claim 3, characterized in that, The gas-liquid separator (6) is located at the exhaust port, which is connected to the expansion tank (5) via a return pipe.

5. The cooling system for a fuel cell according to any one of claims 1-4, characterized in that, The cooling system also includes: The heating core (7) has its inlet connected to the outlet of the cooling channel, and its outlet connected to the inlet of the cooling channel.

6. A control method for a cooling system for a fuel cell, characterized in that, The fuel cell cooling system is the fuel cell cooling system according to any one of claims 1-5, and the control method includes: Obtain the inlet temperature and thermal management mode of the high-temperature radiator (2), wherein the thermal management mode includes: heating mode and non-heating mode; A first control strategy set is generated based on the inlet temperature of the high-temperature radiator (2) and the thermal management mode, wherein the first control strategy set includes at least one of the following: a strategy for regulating the speed of the cooling fan (3), and a strategy for regulating the on / off state of the cooling channel and the warm air core (7).

7. The control method according to claim 6, characterized in that, A first control strategy set is generated based on the inlet temperature of the high-temperature radiator and the thermal management mode, including: When the inlet temperature of the high-temperature radiator (2) is greater than the preset temperature, a first target strategy is generated in the first control strategy set. The first target strategy is used to control the cooling fan (3) to turn on and adjust the speed of the cooling fan (3) according to the inlet temperature of the high-temperature radiator (2).

8. The control method according to claim 6, characterized in that, A first control strategy set is generated based on the inlet temperature of the high-temperature radiator and the thermal management mode, including: When the thermal management mode is the heating mode, a second target strategy is generated in the first control strategy set, wherein the second target strategy is used to control the on / off state of the cooling channel and the warm air core (7).

9. The control method according to claim 6, characterized in that, The control method further includes: Obtain the first working state of the cooling fan (3) and the second working state of the water pump (4); A second control strategy set is generated based on the first operating state and the second operating state, wherein the second control strategy set includes at least one of the following: a strategy to instruct the fuel cell (1) to stop operating, and a strategy to instruct the fuel cell (1) to continue operating.

10. A vehicle comprising a fuel cell, characterized in that, The fuel cell includes a cooling system for a fuel cell according to any one of claims 1-5.

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