Fuel cell hydrogen circulation control method and system with active control of stack inlet temperature

Abstract

The application provides a fuel cell hydrogen circulation control method and system with active control of inlet stack temperature, relates to the technical field of hydrogen circulation control, and warms the hydrogen after pressure reduction; transmits the cooling liquid after heat exchange to a stack cooling liquid outlet loop, transmits the hydrogen after warming to a nozzle through a flow regulating valve, and sprays into an ejector; controls the cooling liquid on the hot side to enter a heat exchanger under the action of a cooling liquid auxiliary water pump, and actively controls the flow of the cooling liquid according to a temperature target value of the gas medium mixed gas entering the stack; the heat exchange amount is controlled by adjusting the flow of the heat source cooling liquid of the heat exchanger, and then the hydrogen is controlled to be warmed. The application significantly improves the efficiency and stability of the fuel cell system by means of efficient utilization of waste heat, optimization of the hydrogen circulation process, realization of active control of the inlet stack temperature and the like.

Description

Technical Field

[0001] This invention proposes a hydrogen cycle control method and system for fuel cells with active control of stack entry temperature, relating to the field of hydrogen cycle control technology, specifically to the field of active temperature control for fuel cell hydrogen cycle control. Background Technology

[0002] In a hydrogen recirculation system, the hydrogen recirculation pump serves as the hydrogen recirculation device. However, the disadvantages of the hydrogen recirculation pump include its high cost due to its precision rotating components, the need for additional power during operation, reduced fuel cell system efficiency, and significant noise. Furthermore, the bearings and impellers of the hydrogen recirculation pump can be corroded by condensate from the recirculated gas. Additionally, when the rotating parts of the hydrogen recirculation pump freeze due to condensate, external heating is required to melt the frozen parts, or high-torque de-icing is used, significantly increasing system complexity and causing additional wear on the rotating parts, affecting the performance and lifespan of the hydrogen recirculation system. To address these issues, an ejector is used as the driving force for hydrogen recirculation and mixes it with fresh hydrogen from the flow control valve before supplying it to the stack. Simultaneously, to compensate for the hydrogen consumed by the electrochemical reactions within the stack and to maintain stable anode pressure, fresh hydrogen stored in the hydrogen storage system is depressurized and accelerated before being introduced into the stack. The nozzles inside the ejector depressurize and accelerate the hydrogen at approximately 1.6 MPa to match the current hydrogen consumption within the stack. As the ejector nozzle diameter increases, the ejection velocity decreases, and the negative pressure suction performance significantly degrades. Conversely, as the ejector nozzle diameter decreases, the ejection velocity increases, and the negative pressure suction capacity significantly improves, but the temperature near the nozzle outlet drops sharply. Because the ejected hydrogen temperature is much lower than the internal stack temperature, it mixes with the high-temperature circulating hydrogen (nearly saturated with water vapor) inside the ejector, producing condensate. This condensate then clogs the flow channels in the head cells of the stack, hindering hydrogen diffusion and causing a low-temperature phenomenon in the head cells. This negatively impacts the performance and lifespan of the fuel cell system. Furthermore, the temperature of the mixed gas cannot be actively controlled, making it difficult to achieve a good match between the stack hydrogen-side temperature and operating conditions. Increasing the temperature of the fresh hydrogen after depressurization and acceleration using external energy heating can effectively alleviate these issues, but this system is complex, requires additional energy, and reduces the efficiency of the fuel cell system.

[0003] The information disclosed above in this background section is only intended to enhance the understanding of the background technology of this invention, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0004] This invention provides a fuel cell hydrogen cycle control method and system with active stack-in temperature control to solve the above-mentioned problems:

[0005] The present invention proposes a fuel cell hydrogen cycle control method and system with active control of infeed temperature, wherein the control method includes:

[0006] S1. The coolant at the outlet of the high-temperature reactor coolant is transferred to the hot side of the heat exchanger, and the depressurized hydrogen is transferred to the cold side of the heat exchanger. The heat pipe of the coolant is transferred to the depressurized hydrogen through the heat exchanger to heat up the depressurized hydrogen.

[0007] S2. The coolant that has completed heat exchange is transferred to the reactor coolant outlet circuit, and the heated hydrogen is transferred to the nozzle through the flow regulating valve and injected into the ejector.

[0008] S3. Control the coolant on the hot side to enter the heat exchanger under the action of the coolant auxiliary water pump, and actively control the flow rate of the coolant according to the target temperature value of the gas medium mixture entering the reactor.

[0009] On the main circuit of the reactor coolant outlet, there is a throttling valve between the inlet and outlet of the heat exchanger coolant. The coolant in the main circuit of the reactor coolant outlet enters the heat exchanger. The flow resistance of the main circuit and the branch circuit is actively adjusted according to the target temperature value of the gas medium mixture entering the reactor, thereby controlling the flow rate of the coolant.

[0010] The heat exchange capacity is controlled by adjusting the flow rate of the heat source coolant in the heat exchanger, thereby controlling the temperature rise of the hydrogen.

[0011] Further, S1 includes:

[0012] The hydrogen is depressurized by the hydrogen pressure reducing valve 110, and the depressurized hydrogen is transmitted to the shut-off valve 112 through the hydrogen supply pipe 111; the shut-off valve 112 is activated to transmit the depressurized hydrogen to the heat exchanger 115.

[0013] High-temperature coolant is introduced into heat exchanger 115 by heat exchanger auxiliary water pump 214;

[0014] The high-temperature coolant is exchanged with the depressurized hydrogen in the heat exchanger 115 to increase the temperature of the depressurized hydrogen and obtain heated hydrogen.

[0015] Further, S2 includes:

[0016] After the heated hydrogen is regulated by the flow control valve 113, a negative pressure is formed through the nozzle of the ejector. The negative pressure attracts the gas medium mixture and liquid water at the stack outlet 103, and then it is transmitted to the gas-liquid separator 122 along the recirculation pipeline 121.

[0017] Liquid water and gaseous medium are separated in gas-liquid separator 122;

[0018] The system receives control commands and controls the liquid water to be discharged through the drain valve 123 and the nitrogen gas to be discharged through the nitrogen discharge valve 124. The gas medium mixture participating in the recirculation is attracted into the ejector 114 by negative pressure and mixed with the heated hydrogen gas before entering the reactor inlet 102.

[0019] Further, S3 includes:

[0020] After the gas medium mixture is introduced into the stack, the feedback temperature data collected by the gas mixture temperature sensor 133 is obtained.

[0021] When the feedback temperature data is lower than the set value and the coolant outlet temperature is higher than the gas medium mixture inlet temperature, the speed of the heat exchanger auxiliary water pump 214 is increased so that the speed is less than or equal to the maximum operating speed.

[0022] When the feedback temperature data collected by the gas-fuel mixture inlet temperature sensor 133 is higher than the set value and the coolant outlet temperature is higher than the gas-fuel mixture inlet temperature, the speed of the heat exchanger auxiliary water pump 214 is reduced, thereby reducing the flow rate of the high-temperature coolant flowing through the heat exchanger.

[0023] When the feedback temperature data collected by the gas-mixed gas inlet temperature sensor 133 is lower than the set value and the coolant outlet temperature is less than or equal to the gas-mixed gas inlet temperature, the speed of the heat exchanger auxiliary water pump 214 is increased so that its speed is less than or equal to the maximum operating speed.

[0024] The pressure difference between the infeed hydrogen pressure sensor 131 and the outfeed pressure sensor 132 is obtained, and the temperature rise rate of the mixed gas entering the reactor is adjusted according to the pressure difference.

[0025] Further, the step of acquiring the pressure difference between the infeed hydrogen pressure sensor 131 and the recycle outlet pressure sensor 132, and adjusting the temperature rise rate of the mixed gas entering the reactor based on the pressure difference, includes:

[0026] When the pressure difference between the infeed hydrogen pressure sensor 131 and the outfeed pressure sensor 132 is higher than the set value, the speed of the heat exchanger auxiliary water pump 214 is reduced to reduce the rate of temperature rise of the mixed gas entering the pile.

[0027] When the pressure difference between the hydrogen pressure sensor 131 and the circulating outlet pressure sensor 132 is lower than the set value, the speed of the heat exchanger auxiliary water pump 214 is increased to increase the temperature rise rate of the mixed gas entering the pile.

[0028] The rotational speed of the heat exchanger auxiliary water pump 214 is replaced by the opening degree of the water circuit back pressure valve 215, and the hydrogen inlet temperature is controlled in the same way.

[0029] Furthermore, the control system includes:

[0030] The heat exchange module is used to transfer the coolant at the outlet of the high-temperature reactor coolant to the hot side of the heat exchanger, transfer the depressurized hydrogen to the cold side of the heat exchanger, and transfer the heat pipe of the coolant to the depressurized hydrogen through the heat exchanger to heat up the depressurized hydrogen.

[0031] The separation and transfer module is used to transfer the coolant that has completed heat exchange to the reactor coolant outlet circuit, and to transfer the heated hydrogen to the nozzle through the flow regulating valve and inject it into the ejector.

[0032] The flow control module is used to control the flow of coolant from the hot side into the heat exchanger under the action of the coolant auxiliary water pump, and actively control the flow rate of coolant according to the target temperature value of the gas medium mixture entering the reactor.

[0033] On the main circuit of the reactor coolant outlet, there is a throttling valve between the inlet and outlet of the heat exchanger coolant. The coolant in the main circuit of the reactor coolant outlet enters the heat exchanger. The flow resistance of the main circuit and the branch circuit is actively adjusted according to the target temperature value of the gas medium mixture entering the reactor, thereby controlling the flow rate of the coolant.

[0034] The heat exchange capacity is controlled by adjusting the flow rate of the heat source coolant in the heat exchanger, thereby controlling the temperature rise of the hydrogen.

[0035] Furthermore, the heat exchange module includes:

[0036] The hydrogen pressure reducing module is used to reduce the pressure of hydrogen through the hydrogen pressure reducing valve 110, and then transmit the reduced hydrogen to the shut-off valve 112 through the hydrogen supply pipe 111; and to control the shut-off valve 112 to start, so that the reduced hydrogen can be transmitted to the heat exchanger 115.

[0037] Cooling water transfer module, used to introduce high-temperature coolant into heat exchanger 115 via heat exchanger auxiliary water pump 214;

[0038] The heat exchange module is used to exchange heat between the high-temperature coolant and the depressurized hydrogen in the heat exchanger 115, thereby increasing the temperature of the depressurized hydrogen and obtaining heated hydrogen.

[0039] Furthermore, the separate transmission module includes:

[0040] The hydrogen transfer module is used to adjust the heated hydrogen through the flow control valve 113, and then form a negative pressure through the nozzle of the ejector to obtain the gas medium mixture and liquid water attracted by the negative pressure at the stack outlet 103, and transfer it to the gas-liquid separator 122 along the recirculation pipeline 121.

[0041] A gas-water separation module is used to separate liquid water and gaseous medium mixture in a gas-water separator 122;

[0042] The ejector mixing module is used to acquire control commands and control the liquid water to be discharged through the drain valve 123 and the nitrogen to be discharged through the nitrogen discharge valve 124 according to the control commands. The gas medium mixture participating in the recirculation is attracted into the ejector 114 by negative pressure, and after mixing with the heated hydrogen, it enters the reactor inlet 102 together.

[0043] Furthermore, the flow control module includes:

[0044] The feedback acquisition module is used to acquire the feedback temperature data collected by the gas medium mixture temperature sensor 133 after the gas medium mixture enters the stack.

[0045] The first speed increase module is used to increase the speed of the heat exchanger auxiliary water pump 214 when the feedback temperature data is lower than the set value and the coolant outlet temperature is higher than the gas medium mixture inlet temperature, so that the speed is less than or equal to the maximum operating speed.

[0046] The speed reduction module is used to reduce the speed of the heat exchanger auxiliary water pump 214 when the feedback temperature data collected by the gas-mixed gas inlet temperature sensor 133 is higher than the set value and the coolant outlet temperature is higher than the gas-mixed gas inlet temperature, thereby reducing the flow rate of the high-temperature coolant flowing through the heat exchanger.

[0047] The second speed increase module is used to increase the speed of the heat exchanger auxiliary water pump 214 so that its speed is less than or equal to the maximum operating speed when the feedback temperature data collected by the gas-mixed gas inlet temperature sensor 133 is lower than the set value and the coolant outlet temperature is less than or equal to the gas-mixed gas inlet temperature.

[0048] The rate control module is used to acquire the pressure difference between the infeed hydrogen pressure sensor 131 and the circulation outlet pressure sensor 132, and adjust the temperature rise rate of the mixed gas entering the reactor according to the pressure difference.

[0049] Furthermore, the rate control module includes:

[0050] The rate reduction module is used to reduce the speed of the heat exchanger auxiliary water pump 214 when the pressure difference between the inlet hydrogen pressure sensor 131 and the outlet pressure sensor 132 is higher than a set value, so as to reduce the rate of temperature rise of the mixed gas entering the pile.

[0051] The rate boosting module is used to increase the rotation speed of the heat exchanger auxiliary water pump 214 when the pressure difference between the infeed hydrogen pressure sensor 131 and the circulation outlet pressure sensor 132 is lower than a set value, so as to increase the temperature rise rate of the mixed gas entering the pile.

[0052] The water pump replacement module is used to replace the rotational speed of the heat exchanger auxiliary water pump 214 with the opening degree of the water circuit back pressure valve 215, and also to control the hydrogen inlet temperature.

[0053] The beneficial effects of this invention are as follows: The high-temperature coolant at the reactor coolant outlet achieves a temperature increase for fresh hydrogen through heat exchange, avoiding the use of external energy sources. Active control of the coolant flow rate into the heat exchanger enables control of the influent gas temperature. Using the high-temperature coolant at the reactor coolant outlet for heat exchange allows for a greater temperature increase in the fresh hydrogen, further mitigating condensation caused by excessively low fresh hydrogen temperatures after the nozzle. Directly transferring heat to the fresh hydrogen using the high-temperature coolant at the reactor coolant outlet reduces the heat dissipation requirements of the main radiator. Simultaneously, the special coolant-driven flow method through the heat exchanger does not increase the flow rate of the fuel cell system's main water pump. Attached Figure Description

[0054] Figure 1 A schematic diagram of a hydrogen cycle control method for fuel cells with active control of infeed temperature;

[0055] Figure 2 A schematic diagram of the existing technology for hydrogen circulation systems in fuel cell systems;

[0056] Figure 3 A schematic diagram showing the speed regulation of the auxiliary water pump 214 for the heat exchanger;

[0057] Figure 4 This is a schematic diagram of the hydrogen circulation system. Detailed Implementation

[0058] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0059] In one embodiment of the present invention, a fuel cell hydrogen cycle control method and system with active stack-in temperature control is proposed, wherein the control method includes:

[0060] Hydrogen is heated by a hydrogen heating module with a hydrogen supply path. A heat source is provided through a pipeline connected to the reactor cooling water inlet. Hydrogen obtained from the hydrogen pressure relief valve is transferred through the hydrogen supply path. The hydrogen flow rate is controlled by a flow control valve connected to the hydrogen heating module. The flow control valve is connected to the nozzle of the ejector module. Circulating gas and liquid water are obtained from the reactor through a hydrogen recirculation module. After gas-water separation, the gas is transferred to the ejector module. The hydrogen recirculation module includes a gas-water separator and a drain / hydrogen discharge solenoid valve. Temperature and pressure sensors are integrated through the reactor inlet interface module to control the pressure and temperature of the gaseous medium mixture.

[0061] S1. The coolant at the outlet of the high-temperature reactor coolant is transferred to the hot side of the heat exchanger, and the depressurized hydrogen is transferred to the cold side of the heat exchanger. The heat pipe of the coolant is transferred to the depressurized hydrogen through the heat exchanger to heat up the depressurized hydrogen.

[0062] S2. The coolant that has completed heat exchange is transferred to the reactor coolant outlet circuit, and the heated hydrogen is transferred to the nozzle through the flow regulating valve and injected into the ejector.

[0063] S3. Control the coolant on the hot side to enter the heat exchanger under the action of the coolant auxiliary water pump, and actively control the flow rate of the coolant according to the target temperature value of the gas medium mixture entering the reactor.

[0064] On the main circuit of the reactor coolant outlet, there is a throttling valve between the inlet and outlet of the heat exchanger coolant. The coolant in the main circuit of the reactor coolant outlet enters the heat exchanger. The flow resistance of the main circuit and the branch circuit is actively adjusted according to the target temperature value of the gas medium mixture entering the reactor, thereby controlling the flow rate of the coolant.

[0065] The heat exchange capacity is controlled by adjusting the flow rate of the heat source coolant in the heat exchanger, thereby controlling the temperature rise of the hydrogen. The "stack" refers to a fuel cell stack.

[0066] The working principle of the above technical solution is as follows: Typically, a fuel cell system includes a fuel cell stack that generates electricity, a fuel supply system that supplies new fuel (hydrogen) and recycled hydrogen to the fuel cell stack, an air supply system that supplies oxygen from the air as the oxidant required for the electrochemical reaction to the fuel cell stack, and a cooling system that discharges the reaction heat of the fuel cell stack to the outside of the system and controls the operating temperature of the fuel cell stack.

[0067] like Figure 2 As shown in the prior art, the hydrogen recirculation system of a fuel cell system is configured to include a hydrogen supply line 111 connected to a hydrogen pressure reducing valve 110, a pressure sensor 131 installed at the hydrogen inlet 102 of the fuel cell stack 401 (hereinafter referred to as the "stack") to measure the hydrogen inlet pressure, a hydrogen shut-off valve and a flow regulator 113 installed on the hydrogen supply line 111. The stack hydrogen outlet 103, along with the hydrogen recirculation line 121, a gas-liquid separator 122, and a hydrogen discharge / drain valve 123, together constitute a gas-liquid separation assembly. An ejector 114 mixes the hydrogen from the flow regulator 113 with the recirculated mixture from the gas-liquid separator 122 and supplies the mixture into the stack.

[0068] Here, ejector 114 injects compressed hydrogen from hydrogen pressure relief valve 110 into the stack through an internal nozzle, and generates negative pressure suction to draw in the mixed gas separated by liquid water from gas-water separator 122, mixes it with fresh hydrogen inside the ejector, and then recycles it back into the stack.

[0069] This invention provides a hydrogen recirculation system for a fuel cell system, comprising a hydrogen heating module with a hydrogen supply path, a pipe connected to the stack coolant inlet to provide a heat source, and a device for regulating the hot water flow rate, through which hydrogen from a hydrogen pressure reducing valve passes; a flow control valve connected to the rear end of the hydrogen heating module to control the flow rate of fresh hydrogen; an ejector module containing a nozzle directly connected to the flow control valve; a hydrogen recirculation module configured to draw recirculated gas and liquid water from the stack, perform gas-liquid separation, and then send them to the ejector module, including a gas-liquid separator and a drain / hydrogen discharge solenoid valve; and a stack inlet interface module integrating temperature and pressure sensors to control the pressure and temperature of the gas mixture entering the stack. Coolant with a higher temperature at the stack coolant outlet is introduced into the hot side of a heat exchanger, and fresh hydrogen is introduced into the cold side of the heat exchanger. The heat pipes of the coolant are transferred to the fresh hydrogen through the heat exchanger, thereby raising the temperature of the fresh hydrogen. The coolant that has completed heat exchange in the heat exchanger returns to the reactor coolant outlet loop, while the heated fresh hydrogen flows through a flow control valve into a nozzle and is injected into the ejector. In a preferred embodiment, the hot-side coolant enters the heat exchanger under the action of a coolant auxiliary pump, and the coolant flow rate is actively controlled according to the target temperature of the incoming gas mixture. In yet another preferred embodiment, a throttling valve exists between the inlet and outlet of the heat exchanger coolant in the main loop at the reactor coolant outlet, forcing the coolant in the main loop into the heat exchanger due to flow resistance. Furthermore, the flow resistance of the main and branch loops can be actively adjusted according to the target temperature of the incoming gas mixture, thereby controlling the coolant flow rate. By adjusting the flow rate of the heat source coolant in the heat exchanger, the heat exchange is controlled, thus controlling the temperature rise of the fresh hydrogen. The principles of a hydrogen circulation system for fuel cell systems with active infeed temperature control include: a hydrogen circulation system using stack coolant as a heat source and a water pump as the coolant drive; a hydrogen circulation system using stack coolant as a heat source and a water back pressure valve as the coolant drive; and the design of a fuzzy controller. Active closed-loop temperature control methods for the hydrogen circulation system in fuel cell systems include: a closed-loop temperature control method for the mixed gas temperature based on the relationship between different stack coolant outlet temperatures, stack inlet temperatures, and mixed gas temperatures; and a closed-loop temperature adjustment method based on the difference between different stack mixed gas inlet pressures and stack mixed gas outlet pressures.

[0070] The technical effects of the above solution are as follows: This invention utilizes the waste heat generated by the fuel cell stack to heat the hydrogen by transferring the coolant from the high-temperature stack coolant outlet to the hot side of the heat exchanger and exchanging heat with the depressurized hydrogen on the cold side of the heat exchanger. This not only improves energy utilization but also achieves precise control of the hydrogen heating temperature through precise control of the coolant flow rate. The hydrogen recirculation module allows the circulating gas and liquid water obtained from the stack to be separated into gas and water before being transferred to the ejector module for reuse. This not only reduces hydrogen waste but also improves the efficiency of the entire hydrogen circulation system. The stack interface module, which integrates temperature and pressure sensors, can monitor the temperature and pressure of the gas medium mixture in real time. Combined with the adjustment of the coolant auxiliary pump and throttle valve, the coolant flow rate can be actively controlled according to the preset temperature target value, thereby achieving precise control of the temperature of the gas medium mixture entering the stack. This active control strategy helps improve the operating efficiency and stability of the fuel cell stack. Through flexible piping design and the integration of various control components (such as flow control valves, throttle valves, and drain / hydrogen discharge solenoid valves), precise control of the hydrogen heating and circulation process is achieved. This not only improves the system's flexibility but also enhances its reliability and stability under various operating conditions.

[0071] In one embodiment of the present invention, S1 includes:

[0072] The hydrogen is depressurized by the hydrogen pressure reducing valve 110, and the depressurized hydrogen is transmitted to the shut-off valve 112 through the hydrogen supply pipe 111; the shut-off valve 112 is activated to transmit the depressurized hydrogen to the heat exchanger 115.

[0073] High-temperature coolant is introduced into heat exchanger 115 by heat exchanger auxiliary water pump 214;

[0074] The high-temperature coolant is exchanged with the depressurized hydrogen in the heat exchanger 115 to increase the temperature of the depressurized hydrogen and obtain heated hydrogen.

[0075] The working principle of the above technical solution is as follows: Figure 3 As shown, label 110 is a hydrogen pressure reducing valve. Hydrogen in the hydrogen storage system is depressurized by the hydrogen pressure reducing valve 110 and then flows through the hydrogen supply pipe 111 to the shut-off valve 112. When the fuel cell system is operating, the shut-off valve 112 is opened, and the fresh hydrogen, depressurized by the hydrogen pressure reducing valve, enters the heat exchanger 115. The heat exchanger auxiliary water pump 214 introduces high-temperature coolant into the heat exchanger 115, where it exchanges heat with the fresh hydrogen, raising the temperature of the fresh hydrogen. At this time, the head of the heat exchanger water pump is equal to the flow resistance of the heat exchanger and the auxiliary coolant piping at a specific flow rate.

[0076] The technical effects of the above solution are as follows: By heating the hydrogen, it can be made to have a higher temperature when entering the fuel cell system, thereby helping to improve the efficiency and performance of the fuel cell. The use of a hydrogen pressure reducing valve ensures that the hydrogen pressure is within a safe range during transmission, reducing the risk of system failure or accidents caused by high pressure. By using high-temperature coolant to heat the hydrogen, not only is the hydrogen temperature increased, but also the heat energy is effectively transferred and utilized, improving the energy efficiency of the entire system. The use of a shut-off valve allows the system to flexibly open or close the hydrogen supply as needed, thereby meeting the requirements under different operating conditions.

[0077] In one embodiment of the present invention, S2 includes:

[0078] After the heated hydrogen is regulated by the flow control valve 113, a negative pressure is formed through the nozzle of the ejector to obtain the gas medium mixture and liquid water attracted by the negative pressure at the stack outlet 103. The gas medium mixture includes excess hydrogen from the electrochemical reaction, nitrogen diffused across the electrolyte, and water vapor, and is transported to the gas-water separator 122 along the recirculation pipeline 121.

[0079] Liquid water and gaseous medium are separated in the gas-water separator 122; the liquid water is temporarily collected in the gas-water separator.

[0080] The system receives control commands and controls the liquid water to be discharged through the drain valve 123 and the nitrogen gas to be discharged through the nitrogen venting valve 124. The gas medium mixture participating in the recirculation is drawn into the ejector 114 by negative pressure and mixed with the heated hydrogen gas before entering the reactor inlet 102.

[0081] The working principle of the above technical solution is as follows: After heating, fresh hydrogen gas is regulated by flow control valve 113 and passes through the nozzle in ejector 114, forming a negative pressure. This negative pressure draws excess hydrogen gas from the reactor's electrochemical reaction, nitrogen gas diffused across the electrolyte, liquid water, and water vapor from the reactor outlet 103 into the gas-liquid separator 122 along the recirculation pipeline 121. In the gas-liquid separator 122, the liquid water is separated from the above-mentioned gaseous medium mixture, and the liquid water is temporarily collected in the gas-liquid separator. According to the control command, the liquid water is discharged through drain valve 123, and the nitrogen gas is discharged through purging valve 124. The gas mixture participating in the recirculation continues to be drawn into ejector 114 by the negative pressure, mixes with fresh hydrogen gas, and then enters reactor inlet 102 together.

[0082] The technical effects of the above solution are as follows: The negative pressure created by the ejector effectively recovers excess hydrogen from the electrochemical reaction at the fuel cell stack outlet, nitrogen diffused across the electrolyte, and water vapor. These resources, which might otherwise be wasted, are reused, improving the overall energy efficiency of the system. The heated fresh hydrogen mixes with the recovered gas mixture in the ejector and then re-enters the fuel cell stack inlet, forming a highly efficient gas circulation management system. This not only helps maintain the stability of the gas composition within the fuel cell stack but also improves the overall gas utilization efficiency. The gas-water separator separates the liquid water from the gaseous medium mixture, avoiding the adverse effects of liquid water on the fuel cell stack performance, such as clogging gas channels or reducing gas diffusion efficiency. Simultaneously, the precise discharge of liquid water and nitrogen according to control commands ensures the stability and reliability of the system operation. The recovery and reuse of excess hydrogen and nitrogen reduces the direct emission of these gases, helping to reduce environmental pollution. Furthermore, precise control of the drainage and nitrogen removal processes reduces unnecessary resource waste and environmental pollution. The introduction of flow control valves, drainage valves, and nitrogen removal valves allows the system to be flexibly adjusted according to actual needs. For example, by adjusting the opening of the flow control valve, the flow rate of fresh hydrogen entering the ejector can be controlled, thereby achieving precise regulation of system performance. Meanwhile, the opening and closing of the drain valve and nitrogen vent valve are also entirely determined by control commands, enhancing the system's controllability and intelligence.

[0083] In one embodiment of the present invention, S3 includes:

[0084] Specifically, according to Figure 2 The schematic diagram of the hydrogen circulation system is shown below. The method for controlling the hydrogen inlet temperature is as follows.

[0085] After the gas medium mixture is introduced into the stack, the feedback temperature data collected by the gas mixture temperature sensor 133 is obtained.

[0086] When the feedback temperature data is lower than the set value and the coolant outlet temperature is higher than the gas medium mixture inlet temperature, the speed of the heat exchanger auxiliary water pump 214 is increased so that the speed is less than or equal to the maximum operating speed. At this time, the flow rate of the high-temperature coolant flowing through the heat exchanger increases, the heat exchange capacity provided by the heat source of the heat exchanger is increased, and the cold side can obtain more heat exchange, thereby increasing the mixture inlet temperature.

[0087] If a fresh hydrogen temperature sensor 133 is configured in the actual system after heat exchange, the temperature of the fresh hydrogen after heat exchange can be controlled more directly.

[0088] When the feedback temperature data collected by the gas-to-fuel mixture inlet temperature sensor 133 is higher than the set value and the coolant outlet temperature is higher than the gas-to-fuel mixture inlet temperature, the speed of the heat exchanger auxiliary water pump 214 is reduced, thereby reducing the flow rate of the high-temperature coolant through the heat exchanger. The reduced heat exchange provided by the heat source of the heat exchanger results in less heat exchange on the cold side, thus lowering the gas-to-fuel mixture inlet temperature. If a fresh hydrogen temperature sensor 133 is configured after heat exchange in the actual system, the temperature of the fresh hydrogen after heat exchange can be controlled more directly.

[0089] When the feedback temperature data collected by the gas-to-fuel mixture inlet temperature sensor 133 is lower than the set value and the coolant outlet temperature is less than or equal to the gas-to-fuel mixture inlet temperature, the speed of the heat exchanger auxiliary water pump 214 is increased to be less than or equal to the maximum operating speed. At this time, the flow rate of the high-temperature coolant flowing through the heat exchanger increases, enhancing the heat exchange capacity provided by the heat source, so that the cold side can obtain more heat exchange, thereby increasing the gas-to-fuel mixture inlet temperature as quickly as possible. If a fresh hydrogen temperature sensor 133 is configured after heat exchange in the actual system, the temperature of the fresh hydrogen after heat exchange can be controlled more directly.

[0090] The pressure difference between the infeed hydrogen pressure sensor 131 and the outfeed pressure sensor 132 is obtained, and the temperature rise rate of the mixed gas entering the reactor is adjusted according to the pressure difference.

[0091] Acquire temperature control process data, and calculate the temperature heat loss coefficient based on the temperature control process data;

[0092] The formula for calculating the temperature heat loss coefficient is as follows:

[0093]

[0094] Among them, K loss T is the temperature heat loss coefficient, β is an experimentally determined coefficient (unitless), and T is the temperature heat loss coefficient. e To preset the ideal hydrogen temperature, T a Q represents the actual hydrogen temperature. in Δt is the heat ratio of the input system relative to the set value, which can be standardized to 1 or other fixed values ​​and has no unit; β is the adjustment value set according to the experimental conditions.

[0095] The temperature heat loss coefficient is compared with a preset heat loss threshold to obtain a loss comparison result;

[0096] Calculate the temperature compensation adjustment coefficient based on the loss comparison results;

[0097] The formula for calculating the temperature compensation adjustment coefficient is as follows:

[0098]

[0099] Among them, T kb K is the temperature compensation adjustment coefficient, α is the adjustment amplitude factor, and its value ranges from -1 to 1 (excluding 0). yy This is a preset heat loss threshold.

[0100] The temperature loss is compensated and adjusted according to the temperature compensation adjustment coefficient until the temperature heat loss coefficient is less than the preset heat loss threshold.

[0101] The working principle of the above technical solution is as follows: When the temperature sensor 133 of the mixed gas entering the reactor feed is lower than the set value and the temperature of the reactor coolant outlet is higher than the temperature of the mixed gas entering the reactor feed, the speed of the heat exchanger auxiliary water pump 214 is increased, while ensuring that its speed is less than or equal to the maximum operating speed. At this time, the flow rate of the high-temperature coolant flowing through the heat exchanger increases, and the heat exchange capacity provided by the heat source of the heat exchanger is increased, so that the cold side can obtain more heat exchange, thereby increasing the temperature of the mixed gas entering the reactor feed. If a fresh hydrogen temperature sensor 133 is configured after heat exchange in the actual system, the temperature of the fresh hydrogen after heat exchange can be controlled more directly.

[0102] When the gas-to-fuel mixture temperature sensor 133 reports a temperature higher than the set value and the coolant outlet temperature is higher than the gas-to-fuel mixture temperature, the auxiliary water pump 214 of the heat exchanger is reduced. This decreases the flow rate of the high-temperature coolant through the heat exchanger, reducing the amount of heat exchanged and thus decreasing the amount of heat received by the cold side, thereby lowering the gas-to-fuel mixture temperature. If a fresh hydrogen temperature sensor 133 is configured in the actual system, the temperature of the fresh hydrogen after heat exchange can be controlled more directly.

[0103] When the mixed gas inlet temperature sensor 133 reports a temperature below the set value and the reactor coolant outlet temperature is less than or equal to the mixed gas inlet temperature, the speed of the heat exchanger auxiliary water pump 214 is increased, ensuring that its speed is less than or equal to the maximum operating speed. This increases the flow rate of the high-temperature coolant through the heat exchanger, enhancing the heat exchange capacity provided by the heat source, allowing the cold side to acquire more heat and thus raising the mixed gas inlet temperature as quickly as possible. If a fresh hydrogen temperature sensor 133 is configured in the actual system after heat exchange, the temperature of the fresh hydrogen after heat exchange can be controlled more directly.

[0104] The technical effects of the above solution are as follows: When the mixed gas inlet temperature sensor 133 reports a temperature lower than the set value, the rotation speed of the heat exchanger auxiliary water pump 214 is increased, thereby increasing the flow rate of the high-temperature coolant through the heat exchanger and enhancing the heat exchange capacity provided by the heat source, thus raising the mixed gas inlet temperature. This ensures that the fuel cell system can operate within a more efficient temperature range, improving the overall energy efficiency of the system. By monitoring the mixed gas inlet temperature and the stack coolant outlet temperature in real time, and dynamically adjusting the rotation speed of the heat exchanger auxiliary water pump 214 according to the temperature difference, the system can quickly respond to temperature changes and maintain the mixed gas inlet temperature within the set ideal range. This helps maintain the stable operation of the fuel cell system and extends its lifespan. If a fresh hydrogen temperature sensor 133 is configured in the actual system after heat exchange, the temperature of the fresh hydrogen after heat exchange can be controlled more directly. This direct temperature feedback mechanism makes the temperature control strategy more precise and efficient, helping to achieve finer temperature regulation and higher system performance. The dynamic adjustment of the rotation speed of the heat exchanger auxiliary water pump 214 to adapt to different temperature conditions demonstrates the high flexibility of the system. Regardless of whether the gas mixture temperature at the reactor core is below or above the set value, the system can maintain temperature stability through appropriate adjustment measures. Through precise temperature control and optimized heat exchange processes, the system reduces system failures and damage caused by temperature fluctuations, thereby lowering maintenance costs.

[0105] In one embodiment of the present invention, the step of obtaining the pressure difference between the infeed hydrogen pressure sensor 131 and the recycle outlet pressure sensor 132, and adjusting the temperature rise rate of the mixed gas entering the reactor based on the pressure difference, includes:

[0106] When the pressure difference between the infeed hydrogen pressure sensor 131 and the outfeed pressure sensor 132 is higher than the set value, the speed of the heat exchanger auxiliary water pump 214 is reduced to reduce the rate of temperature rise of the mixed gas entering the pile.

[0107] When the pressure difference between the hydrogen pressure sensor 131 and the circulating outlet pressure sensor 132 is lower than the set value, the speed of the heat exchanger auxiliary water pump 214 is increased to increase the temperature rise rate of the mixed gas entering the pile.

[0108] The rotational speed of the heat exchanger auxiliary water pump 214 is replaced by the opening degree of the water circuit back pressure valve 215, and the hydrogen inlet temperature is controlled in the same way.

[0109] The working principle of the above technical solution is as follows: If the pressure difference between the inlet hydrogen pressure sensor 131 and the outlet pressure sensor 132 is higher than the set value, it indicates that the circulation flow rate is higher than the set value / calibrated value. At this time, the speed of the heat exchanger auxiliary water pump 214 can be reduced in advance to reduce the temperature rise rate of the mixed gas entering the stack. If the pressure difference between the inlet hydrogen pressure sensor 131 and the outlet pressure sensor 132 is lower than the set value, it indicates that the circulation flow rate is lower than the set value / calibrated value. At this time, the speed of the heat exchanger auxiliary water pump 214 can be increased in advance, ensuring that its speed is less than or equal to the maximum operating speed, to increase the temperature rise rate of the mixed gas entering the stack. Figure 4 As shown, label 110 is a hydrogen pressure reducing valve. Hydrogen in the hydrogen storage system is depressurized by the hydrogen pressure reducing valve 110 and then flows through the hydrogen supply pipe 111 to the shut-off valve 112. When the fuel cell system is operating, the shut-off valve 112 is opened, allowing fresh hydrogen, depressurized by the hydrogen pressure reducing valve, to enter the heat exchanger 115. The opening of the water back pressure valve 215 is reduced to introduce high-temperature coolant into the heat exchanger 115, where it exchanges heat with the fresh hydrogen, raising the temperature of the fresh hydrogen. At this time, the flow resistance provided by the water back pressure valve is equal to the flow resistance of the heat exchanger and the auxiliary coolant piping at a specific flow rate. The heated fresh hydrogen, after being regulated by the flow control valve 113, passes through the nozzle in the ejector 114, creating a negative pressure. This negative pressure draws excess hydrogen from the electrochemical reaction within the reactor, nitrogen diffused across the electrolyte, liquid water, and water vapor from the reactor outlet 103, which then flows along the recirculation pipe 121 into the gas-liquid separator 122. The liquid water is separated from the gaseous mixture in the gas-liquid separator 122, and the liquid water is temporarily collected in the gas-liquid separator. According to the control command, the liquid water is discharged through the drain valve 123, and the nitrogen is discharged through the purge valve 124. The gas mixture participating in the recirculation continues to be drawn into the ejector 114 by negative pressure, and after mixing with fresh hydrogen, it enters the reactor inlet 102 together.

[0110] according to Figure 4 The schematic diagram of the hydrogen circulation system is shown below. The method for controlling the hydrogen inlet temperature is as follows.

[0111] When the mixed gas inlet temperature sensor 133 reports a temperature lower than the set value and the coolant outlet temperature is higher than the mixed gas inlet temperature, the opening of valve 214 is reduced (the default opening is 90° in the fully open state and 0° in the fully closed state; the opening range of the water back pressure valve is 0~90°), and the pressure reported by the coolant inlet pressure sensor 222 is ensured not to exceed the set threshold. At this time, the flow rate of the high-temperature coolant flowing through the heat exchanger increases, and the heat exchange capacity provided by the heat source of the heat exchanger increases, allowing the cold side to obtain more heat exchange, thereby increasing the mixed gas inlet temperature. If a fresh hydrogen temperature sensor 133 is configured after heat exchange in the actual system, the temperature of the fresh hydrogen after heat exchange can be controlled more directly.

[0112] When the mixed gas inlet temperature sensor 133 reports a value higher than the set value and the coolant outlet temperature is higher than the mixed gas inlet temperature, the opening of the water back pressure valve 215 is increased. This reduces the flow rate of the high-temperature coolant through the heat exchanger, decreasing the heat exchange capacity provided by the heat source and thus reducing the heat exchange capacity acquired by the cold side, thereby lowering the mixed gas inlet temperature. Specifically, if the water back pressure valve 215 is fully open, the coolant in the heat exchanger hardly flows. If a fresh hydrogen temperature sensor 133 is configured in the actual system, the temperature of the fresh hydrogen after heat exchange can be controlled more directly.

[0113] When the mixed gas inlet temperature sensor 133 reports a temperature below the set value and the reactor coolant outlet temperature is less than or equal to the mixed gas inlet temperature, the opening of the water back pressure 214 is reduced, and the pressure reported by the reactor water inlet pressure sensor 222 is ensured not to exceed the set threshold. At this time, the flow rate of the high-temperature coolant flowing through the heat exchanger increases, enhancing the heat exchange capacity provided by the heat source, so that the cold side can obtain more heat exchange, thereby increasing the mixed gas inlet temperature as quickly as possible. If a fresh hydrogen temperature sensor 133 is configured after heat exchange in the actual system, the temperature of the fresh hydrogen after heat exchange can be controlled more directly.

[0114] If the pressure difference between the inlet hydrogen pressure sensor 131 and the outlet pressure sensor 132 is higher than the set value, it indicates that the circulation flow rate is higher than the set value / calibrated value. In this case, the opening of the water circuit back pressure valve 215 can be increased in advance to slow down the temperature rise rate of the mixed gas entering the reactor. If the pressure difference between the inlet hydrogen pressure sensor 131 and the outlet pressure sensor 132 is lower than the set value, it indicates that the circulation flow rate is lower than the set value / calibrated value. In this case, the rotational speed of the water circuit back pressure valve 215 can be reduced in advance, and its rotational speed can be ensured to be less than or equal to the maximum operating speed to increase the temperature rise rate of the mixed gas entering the reactor.

[0115] The technical effects of the above solution are as follows: By monitoring the pressure difference between the hydrogen inlet pressure and the circulating outlet pressure in real time, the system can quickly sense pressure changes inside the fuel cell stack and adjust the speed of the heat exchanger auxiliary water pump 214 or the opening of the water circuit back pressure valve 215 accordingly, thereby achieving rapid adjustment of the temperature rise rate of the mixed gas entering the stack. This improves the system's response speed and helps maintain the fuel cell stack operating under stable conditions. When the pressure difference is higher than the set value, the speed of the heat exchanger auxiliary water pump 214 is reduced, decreasing the flow rate of the high-temperature coolant, thereby reducing the temperature rise rate of the mixed gas entering the stack. This helps prevent excessive energy loss due to hydrogen overheating and improves hydrogen utilization efficiency. By dynamically adjusting the temperature rise rate of the mixed gas entering the stack, the system can maintain pressure balance and temperature stability inside the fuel cell stack, avoiding system fluctuations or malfunctions caused by excessive pressure or temperature changes. This enhances the system's stability and reliability. The temperature rise rate can be controlled not only by adjusting the speed of the heat exchanger auxiliary water pump 214 but also by adjusting the opening of the water circuit back pressure valve 215. The choice of multiple control methods makes the system more flexible, allowing it to adapt to different operating conditions and needs. Through precise temperature and pressure control, the system can reduce unnecessary energy loss and waste, thereby lowering energy consumption. At the same time, stable operating conditions also help extend the service life of system components and reduce maintenance costs.

[0116] In one embodiment of the present invention, the control system includes:

[0117] Hydrogen is heated by a hydrogen heating module with a hydrogen supply path. A heat source is provided through a pipeline connected to the reactor cooling water inlet. Hydrogen obtained from the hydrogen pressure relief valve is transferred through the hydrogen supply path. The hydrogen flow rate is controlled by a flow control valve connected to the hydrogen heating module. The flow control valve is connected to the nozzle of the ejector module. Circulating gas and liquid water are obtained from the reactor through a hydrogen recirculation module. After gas-water separation, the gas is transferred to the ejector module. The hydrogen recirculation module includes a gas-water separator and a drain / hydrogen discharge solenoid valve. Temperature and pressure sensors are integrated through the reactor inlet interface module to control the pressure and temperature of the gaseous medium mixture.

[0118] The heat exchange module is used to transfer the coolant at the outlet of the high-temperature reactor coolant to the hot side of the heat exchanger, transfer the depressurized hydrogen to the cold side of the heat exchanger, and transfer the heat pipe of the coolant to the depressurized hydrogen through the heat exchanger to heat up the depressurized hydrogen.

[0119] The separation and transfer module is used to transfer the coolant that has completed heat exchange to the reactor coolant outlet circuit, and to transfer the heated hydrogen to the nozzle through the flow regulating valve and inject it into the ejector.

[0120] The flow control module is used to control the flow of coolant from the hot side into the heat exchanger under the action of the coolant auxiliary water pump, and actively control the flow rate of coolant according to the target temperature value of the gas medium mixture entering the reactor.

[0121] On the main circuit of the reactor coolant outlet, there is a throttling valve between the inlet and outlet of the heat exchanger coolant. The coolant in the main circuit of the reactor coolant outlet enters the heat exchanger. The flow resistance of the main circuit and the branch circuit is actively adjusted according to the target temperature value of the gas medium mixture entering the reactor, thereby controlling the flow rate of the coolant.

[0122] The heat exchange capacity is controlled by adjusting the flow rate of the heat source coolant in the heat exchanger, thereby controlling the temperature rise of the hydrogen. The "stack" refers to a fuel cell stack.

[0123] The working principle of the above technical solution is as follows: This invention provides a hydrogen circulation system device for a fuel cell system, which includes a hydrogen heating module with a hydrogen supply path, a pipeline connected to the stack cooling water inlet to provide a heat source, and a device to regulate the hot water flow rate. Hydrogen from a hydrogen pressure reducing valve passes through this hydrogen supply path. A flow control valve is connected to the rear end of the hydrogen heating module to control the flow rate of fresh hydrogen. An ejector module has a nozzle and is directly connected to the flow control valve. A hydrogen recirculation module is configured to draw out circulating gas and liquid water from the stack, perform gas-water separation, and send them to the ejector module, including a gas-water separator and a drain / hydrogen discharge solenoid valve. A stack inlet interface module integrates temperature and pressure sensors to control the pressure and temperature of the mixed gas entering the stack. Coolant with a higher temperature at the stack coolant outlet is introduced into the hot side of the heat exchanger, and fresh hydrogen is introduced into the cold side of the heat exchanger. The heat pipe of the coolant is transferred to the fresh hydrogen through the heat exchanger, thereby raising the temperature of the fresh hydrogen. The coolant that has completed heat exchange in the heat exchanger returns to the reactor coolant outlet loop, while the heated fresh hydrogen flows through a flow control valve into a nozzle and is injected into the ejector. In a preferred embodiment, the hot-side coolant enters the heat exchanger under the action of a coolant auxiliary pump, and the coolant flow rate is actively controlled according to the target temperature of the incoming gas mixture. In yet another preferred embodiment, a throttling valve exists between the inlet and outlet of the heat exchanger coolant in the main loop at the reactor coolant outlet, forcing the coolant in the main loop into the heat exchanger due to flow resistance. Furthermore, the flow resistance of the main and branch loops can be actively adjusted according to the target temperature of the incoming gas mixture, thereby controlling the coolant flow rate. By adjusting the flow rate of the heat source coolant in the heat exchanger, the heat exchange is controlled, thus controlling the temperature rise of the fresh hydrogen. The principles of a hydrogen circulation system for fuel cell systems with active infeed temperature control include: a hydrogen circulation system using stack coolant as a heat source and a water pump as the coolant drive; a hydrogen circulation system using stack coolant as a heat source and a water back pressure valve as the coolant drive; and the design of a fuzzy controller. Active closed-loop temperature control methods for the hydrogen circulation system in fuel cell systems include: a closed-loop temperature control method for the mixed gas temperature based on the relationship between different stack coolant outlet temperatures, stack inlet temperatures, and mixed gas temperatures; and a closed-loop temperature adjustment method based on the difference between different stack mixed gas inlet pressures and stack mixed gas outlet pressures.

[0124] The technical effects of the above solution are as follows: This invention utilizes the waste heat generated by the fuel cell stack to heat the hydrogen by transferring the coolant from the high-temperature stack coolant outlet to the hot side of the heat exchanger and exchanging heat with the depressurized hydrogen on the cold side of the heat exchanger. This not only improves energy utilization but also achieves precise control of the hydrogen heating temperature through precise control of the coolant flow rate. The hydrogen recirculation module allows the circulating gas and liquid water obtained from the stack to be separated into gas and water before being transferred to the ejector module for reuse. This not only reduces hydrogen waste but also improves the efficiency of the entire hydrogen circulation system. The stack interface module, which integrates temperature and pressure sensors, can monitor the temperature and pressure of the gas medium mixture in real time. Combined with the adjustment of the coolant auxiliary pump and throttle valve, the coolant flow rate can be actively controlled according to the preset temperature target value, thereby achieving precise control of the temperature of the gas medium mixture entering the stack. This active control strategy helps improve the operating efficiency and stability of the fuel cell stack. Through flexible piping design and the integration of various control components (such as flow control valves, throttle valves, and drain / hydrogen discharge solenoid valves), precise control of the hydrogen heating and circulation process is achieved. This not only improves the system's flexibility but also enhances its reliability and stability under various operating conditions.

[0125] In one embodiment of the present invention, the heat exchange module includes:

[0126] The hydrogen pressure reducing module is used to reduce the pressure of hydrogen through the hydrogen pressure reducing valve 110, and then transmit the reduced hydrogen to the shut-off valve 112 through the hydrogen supply pipe 111; and to control the shut-off valve 112 to start, so that the reduced hydrogen can be transmitted to the heat exchanger 115.

[0127] Cooling water transfer module, used to introduce high-temperature coolant into heat exchanger 115 via heat exchanger auxiliary water pump 214;

[0128] The heat exchange module is used to exchange heat between the high-temperature coolant and the depressurized hydrogen in the heat exchanger 115, thereby increasing the temperature of the depressurized hydrogen and obtaining heated hydrogen.

[0129] The working principle of the above technical solution is as follows: Figure 3 As shown, label 110 is a hydrogen pressure reducing valve. Hydrogen in the hydrogen storage system is depressurized by the hydrogen pressure reducing valve 110 and then flows through the hydrogen supply pipe 111 to the shut-off valve 112. When the fuel cell system is operating, the shut-off valve 112 is opened, and the fresh hydrogen, depressurized by the hydrogen pressure reducing valve, enters the heat exchanger 115. The heat exchanger auxiliary water pump 214 introduces high-temperature coolant into the heat exchanger 115, where it exchanges heat with the fresh hydrogen, raising the temperature of the fresh hydrogen. At this time, the head of the heat exchanger water pump is equal to the flow resistance of the heat exchanger and the auxiliary coolant piping at a specific flow rate.

[0130] The technical effects of the above solution are as follows: By heating the hydrogen, it can be made to have a higher temperature when entering the fuel cell system, thereby helping to improve the efficiency and performance of the fuel cell. The use of a hydrogen pressure reducing valve ensures that the hydrogen pressure is within a safe range during transmission, reducing the risk of system failure or accidents caused by high pressure. By using high-temperature coolant to heat the hydrogen, not only is the hydrogen temperature increased, but also the heat energy is effectively transferred and utilized, improving the energy efficiency of the entire system. The use of a shut-off valve allows the system to flexibly open or close the hydrogen supply as needed, thereby meeting the requirements under different operating conditions.

[0131] In one embodiment of the present invention, the separate transmission module includes:

[0132] The hydrogen transfer module is used to adjust the heated hydrogen through the flow control valve 113, and then form a negative pressure through the nozzle of the ejector to obtain the gas medium mixture and liquid water attracted by the negative pressure at the stack outlet 103. The gas medium mixture includes excess hydrogen from electrochemical reaction, nitrogen diffused across the electrolyte and water vapor, and is transferred to the gas-water separator 122 along the recirculation pipeline 121.

[0133] The gas-water separation module is used to separate liquid water and gaseous medium mixture in the gas-water separator 122; the liquid water is temporarily collected in the gas-water separator.

[0134] The ejector mixing module is used to acquire control commands and control the liquid water to be discharged through the drain valve 123 and the nitrogen to be discharged through the nitrogen venting valve 124 according to the control commands. The gas medium mixture participating in the recirculation is attracted into the ejector 114 by negative pressure, and after mixing with the heated hydrogen, it enters the reactor inlet 102 together.

[0135] The working principle of the above technical solution is as follows: After heating, fresh hydrogen gas is regulated by flow control valve 113 and passes through the nozzle in ejector 114, forming a negative pressure. This negative pressure draws excess hydrogen gas from the reactor's electrochemical reaction, nitrogen gas diffused across the electrolyte, liquid water, and water vapor from the reactor outlet 103 into the gas-liquid separator 122 along the recirculation pipeline 121. In the gas-liquid separator 122, the liquid water is separated from the above-mentioned gaseous medium mixture, and the liquid water is temporarily collected in the gas-liquid separator. According to the control command, the liquid water is discharged through drain valve 123, and the nitrogen gas is discharged through purging valve 124. The gas mixture participating in the recirculation continues to be drawn into ejector 114 by the negative pressure, mixes with fresh hydrogen gas, and then enters reactor inlet 102 together.

[0136] The technical effects of the above solution are as follows: The negative pressure created by the ejector effectively recovers excess hydrogen from the electrochemical reaction at the fuel cell stack outlet, nitrogen diffused across the electrolyte, and water vapor. These resources, which might otherwise be wasted, are reused, improving the overall energy efficiency of the system. The heated fresh hydrogen mixes with the recovered gas mixture in the ejector and then re-enters the fuel cell stack inlet, forming a highly efficient gas circulation management system. This not only helps maintain the stability of the gas composition within the fuel cell stack but also improves the overall gas utilization efficiency. The gas-water separator separates the liquid water from the gaseous medium mixture, avoiding the adverse effects of liquid water on the fuel cell stack performance, such as clogging gas channels or reducing gas diffusion efficiency. Simultaneously, the precise discharge of liquid water and nitrogen according to control commands ensures the stability and reliability of the system operation. The recovery and reuse of excess hydrogen and nitrogen reduces the direct emission of these gases, helping to reduce environmental pollution. Furthermore, precise control of the drainage and nitrogen removal processes reduces unnecessary resource waste and environmental pollution. The introduction of flow control valves, drainage valves, and nitrogen removal valves allows the system to be flexibly adjusted according to actual needs. For example, by adjusting the opening of the flow control valve, the flow rate of fresh hydrogen entering the ejector can be controlled, thereby achieving precise regulation of system performance. Meanwhile, the opening and closing of the drain valve and nitrogen vent valve are also entirely determined by control commands, enhancing the system's controllability and intelligence.

[0137] In one embodiment of the present invention, the flow control module includes:

[0138] Specifically, according to Figure 2 The schematic diagram of the hydrogen circulation system is shown below. The method for controlling the hydrogen inlet temperature is as follows.

[0139] The feedback acquisition module is used to acquire the feedback temperature data collected by the gas medium mixture temperature sensor 133 after the gas medium mixture enters the stack.

[0140] The first speed increase module is used to increase the speed of the heat exchanger auxiliary water pump 214 when the feedback temperature data is lower than the set value and the coolant outlet temperature is higher than the gas medium mixed gas inlet temperature. This increases the speed to be less than or equal to the maximum operating speed. At this time, the flow rate of the high-temperature coolant flowing through the heat exchanger increases, and the heat exchange capacity provided by the heat source of the heat exchanger increases, so that the cold side can obtain more heat exchange, thereby increasing the mixed gas inlet temperature.

[0141] If a fresh hydrogen temperature sensor 133 is configured in the actual system after heat exchange, the temperature of the fresh hydrogen after heat exchange can be controlled more directly.

[0142] The speed reduction module is used to reduce the speed of the heat exchanger auxiliary water pump 214 when the feedback temperature data collected by the gas-to-fuel mixture inlet temperature sensor 133 is higher than the set value and the coolant outlet temperature is higher than the gas-to-fuel mixture inlet temperature. This reduces the flow rate of the high-temperature coolant through the heat exchanger. The reduced heat exchange provided by the heat source of the heat exchanger results in less heat exchange on the cold side, thereby lowering the gas-to-fuel mixture inlet temperature. If a fresh hydrogen temperature sensor 133 is configured after heat exchange in the actual system, the temperature of the fresh hydrogen after heat exchange can be controlled more directly.

[0143] The second speed-increasing module is used to increase the speed of the heat exchanger auxiliary water pump 214 when the feedback temperature data collected by the gas-to-fuel mixture inlet temperature sensor 133 is lower than the set value and the coolant outlet temperature is less than or equal to the gas-to-fuel mixture inlet temperature. This increases the speed to be less than or equal to the maximum operating speed. At this time, the flow rate of the high-temperature coolant through the heat exchanger increases, enhancing the heat exchange capacity provided by the heat source, allowing the cold side to acquire more heat exchange and thus increasing the gas-to-fuel mixture inlet temperature as quickly as possible. If a fresh hydrogen temperature sensor 133 is configured after heat exchange in the actual system, the temperature of the fresh hydrogen after heat exchange can be controlled more directly.

[0144] The rate control module is used to acquire the pressure difference between the infeed hydrogen pressure sensor 131 and the circulation outlet pressure sensor 132, and adjust the temperature rise rate of the mixed gas entering the reactor according to the pressure difference.

[0145] Acquire temperature control process data, and calculate the temperature heat loss coefficient based on the temperature control process data;

[0146] The formula for calculating the temperature heat loss coefficient is as follows:

[0147]

[0148] Among them, K loss T is the temperature heat loss coefficient, β is an experimentally determined coefficient (unitless), and T is the temperature heat loss coefficient. e To preset the ideal hydrogen temperature, T a Q represents the actual hydrogen temperature. in Δt is the heat ratio of the input system relative to the set value, which can be standardized to 1 or other fixed values ​​and has no unit; β is the adjustment value set according to the experimental conditions.

[0149] The temperature heat loss coefficient is compared with a preset heat loss threshold to obtain a loss comparison result;

[0150] Calculate the temperature compensation adjustment coefficient based on the loss comparison results;

[0151] The formula for calculating the temperature compensation adjustment coefficient is as follows:

[0152]

[0153] Among them, T kb K is the temperature compensation adjustment coefficient, α is the adjustment amplitude factor, and its value ranges from -1 to 1 (excluding 0). yy This is a preset heat loss threshold.

[0154] The working principle of the above technical solution is as follows: When the temperature sensor 133 of the mixed gas entering the reactor feed is lower than the set value and the temperature of the reactor coolant outlet is higher than the temperature of the mixed gas entering the reactor feed, the speed of the heat exchanger auxiliary water pump 214 is increased, while ensuring that its speed is less than or equal to the maximum operating speed. At this time, the flow rate of the high-temperature coolant flowing through the heat exchanger increases, and the heat exchange capacity provided by the heat source of the heat exchanger is increased, so that the cold side can obtain more heat exchange, thereby increasing the temperature of the mixed gas entering the reactor feed. If a fresh hydrogen temperature sensor 133 is configured after heat exchange in the actual system, the temperature of the fresh hydrogen after heat exchange can be controlled more directly.

[0155] When the gas-to-fuel mixture temperature sensor 133 reports a temperature higher than the set value and the coolant outlet temperature is higher than the gas-to-fuel mixture temperature, the auxiliary water pump 214 of the heat exchanger is reduced. This decreases the flow rate of the high-temperature coolant through the heat exchanger, reducing the amount of heat exchanged and thus decreasing the amount of heat received by the cold side, thereby lowering the gas-to-fuel mixture temperature. If a fresh hydrogen temperature sensor 133 is configured in the actual system, the temperature of the fresh hydrogen after heat exchange can be controlled more directly.

[0156] When the mixed gas inlet temperature sensor 133 reports a temperature below the set value and the reactor coolant outlet temperature is less than or equal to the mixed gas inlet temperature, the speed of the heat exchanger auxiliary water pump 214 is increased, ensuring that its speed is less than or equal to the maximum operating speed. This increases the flow rate of the high-temperature coolant through the heat exchanger, enhancing the heat exchange capacity provided by the heat source, allowing the cold side to acquire more heat and thus raising the mixed gas inlet temperature as quickly as possible. If a fresh hydrogen temperature sensor 133 is configured in the actual system after heat exchange, the temperature of the fresh hydrogen after heat exchange can be controlled more directly.

[0157] The technical effects of the above solution are as follows: When the mixed gas inlet temperature sensor 133 reports a temperature lower than the set value, the rotation speed of the heat exchanger auxiliary water pump 214 is increased, thereby increasing the flow rate of the high-temperature coolant through the heat exchanger and enhancing the heat exchange capacity provided by the heat source, thus raising the mixed gas inlet temperature. This ensures that the fuel cell system can operate within a more efficient temperature range, improving the overall energy efficiency of the system. By monitoring the mixed gas inlet temperature and the stack coolant outlet temperature in real time, and dynamically adjusting the rotation speed of the heat exchanger auxiliary water pump 214 according to the temperature difference, the system can quickly respond to temperature changes and maintain the mixed gas inlet temperature within the set ideal range. This helps maintain the stable operation of the fuel cell system and extends its lifespan. If a fresh hydrogen temperature sensor 133 is configured in the actual system after heat exchange, the temperature of the fresh hydrogen after heat exchange can be controlled more directly. This direct temperature feedback mechanism makes the temperature control strategy more precise and efficient, helping to achieve finer temperature regulation and higher system performance. The dynamic adjustment of the rotation speed of the heat exchanger auxiliary water pump 214 to adapt to different temperature conditions demonstrates the high flexibility of the system. Regardless of whether the gas mixture temperature at the reactor core is below or above the set value, the system can maintain temperature stability through appropriate adjustment measures. Through precise temperature control and optimized heat exchange processes, the system reduces system failures and damage caused by temperature fluctuations, thereby lowering maintenance costs.

[0158] In one embodiment of the present invention, the rate control module includes:

[0159] The rate reduction module is used to reduce the speed of the heat exchanger auxiliary water pump 214 when the pressure difference between the inlet hydrogen pressure sensor 131 and the outlet pressure sensor 132 is higher than a set value, so as to reduce the rate of temperature rise of the mixed gas entering the pile.

[0160] The rate boosting module is used to increase the rotation speed of the heat exchanger auxiliary water pump 214 when the pressure difference between the infeed hydrogen pressure sensor 131 and the circulation outlet pressure sensor 132 is lower than a set value, so as to increase the temperature rise rate of the mixed gas entering the pile.

[0161] The water pump replacement module is used to replace the rotational speed of the heat exchanger auxiliary water pump 214 with the opening degree of the water circuit back pressure valve 215, and also to control the hydrogen inlet temperature.

[0162] The working principle of the above technical solution is as follows: If the pressure difference between the inlet hydrogen pressure sensor 131 and the outlet pressure sensor 132 is higher than the set value, it indicates that the circulation flow rate is higher than the set value / calibrated value. At this time, the speed of the heat exchanger auxiliary water pump 214 can be reduced in advance to reduce the temperature rise rate of the mixed gas entering the stack. If the pressure difference between the inlet hydrogen pressure sensor 131 and the outlet pressure sensor 132 is lower than the set value, it indicates that the circulation flow rate is lower than the set value / calibrated value. At this time, the speed of the heat exchanger auxiliary water pump 214 can be increased in advance, ensuring that its speed is less than or equal to the maximum operating speed, to increase the temperature rise rate of the mixed gas entering the stack. Figure 4 As shown, label 110 is a hydrogen pressure reducing valve. Hydrogen in the hydrogen storage system is depressurized by the hydrogen pressure reducing valve 110 and then flows through the hydrogen supply pipe 111 to the shut-off valve 112. When the fuel cell system is operating, the shut-off valve 112 is opened, allowing fresh hydrogen, depressurized by the hydrogen pressure reducing valve, to enter the heat exchanger 115. The opening of the water back pressure valve 215 is reduced to introduce high-temperature coolant into the heat exchanger 115, where it exchanges heat with the fresh hydrogen, raising the temperature of the fresh hydrogen. At this time, the flow resistance provided by the water back pressure valve is equal to the flow resistance of the heat exchanger and the auxiliary coolant piping at a specific flow rate. The heated fresh hydrogen, after being regulated by the flow control valve 113, passes through the nozzle in the ejector 114, creating a negative pressure. This negative pressure draws excess hydrogen from the electrochemical reaction within the reactor, nitrogen diffused across the electrolyte, liquid water, and water vapor from the reactor outlet 103, which then flows along the recirculation pipe 121 into the gas-liquid separator 122. The liquid water is separated from the gaseous mixture in the gas-liquid separator 122, and the liquid water is temporarily collected in the gas-liquid separator. According to the control command, the liquid water is discharged through the drain valve 123, and the nitrogen is discharged through the purge valve 124. The gas mixture participating in the recirculation continues to be drawn into the ejector 114 by negative pressure, and after mixing with fresh hydrogen, it enters the reactor inlet 102 together.

[0163] The technical effects of the above solution are as follows: By monitoring the pressure difference between the hydrogen inlet pressure and the circulating outlet pressure in real time, the system can quickly sense pressure changes inside the fuel cell stack and adjust the speed of the heat exchanger auxiliary water pump 214 or the opening of the water circuit back pressure valve 215 accordingly, thereby achieving rapid adjustment of the temperature rise rate of the mixed gas entering the stack. This improves the system's response speed and helps maintain the fuel cell stack operating under stable conditions. When the pressure difference is higher than the set value, the speed of the heat exchanger auxiliary water pump 214 is reduced, decreasing the flow rate of the high-temperature coolant, thereby reducing the temperature rise rate of the mixed gas entering the stack. This helps prevent excessive energy loss due to hydrogen overheating and improves hydrogen utilization efficiency. By dynamically adjusting the temperature rise rate of the mixed gas entering the stack, the system can maintain pressure balance and temperature stability inside the fuel cell stack, avoiding system fluctuations or malfunctions caused by excessive pressure or temperature changes. This enhances the system's stability and reliability. The temperature rise rate can be controlled not only by adjusting the speed of the heat exchanger auxiliary water pump 214 but also by adjusting the opening of the water circuit back pressure valve 215. The choice of multiple control methods makes the system more flexible, allowing it to adapt to different operating conditions and needs. Through precise temperature and pressure control, the system can reduce unnecessary energy loss and waste, thereby lowering energy consumption. At the same time, stable operating conditions also help extend the service life of system components and reduce maintenance costs.

[0164] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A fuel cell hydrogen cycle control method with active control of stack entry temperature, characterized in that, The control method includes: S1. The coolant at the outlet of the high-temperature reactor coolant is transferred to the hot side of the heat exchanger, and the depressurized hydrogen is transferred to the cold side of the heat exchanger. The heat of the coolant is transferred to the depressurized hydrogen through the heat exchanger to raise the temperature of the depressurized hydrogen. S2. The coolant that has completed heat exchange is transferred to the reactor coolant outlet circuit, and the heated hydrogen is transferred to the nozzle through the flow regulating valve and injected into the ejector. S3. Control the coolant on the hot side to enter the heat exchanger under the action of the coolant auxiliary water pump, and actively control the flow rate of the coolant according to the target temperature value of the gas medium mixture entering the reactor. On the main circuit of the reactor coolant outlet, there is a throttling valve between the inlet and outlet of the heat exchanger coolant. The coolant in the main circuit of the reactor coolant outlet enters the heat exchanger. The flow resistance of the main circuit and the branch circuit is actively adjusted according to the target temperature value of the gas medium mixture entering the reactor, thereby controlling the flow rate of the coolant. The heat exchange capacity is controlled by adjusting the flow rate of the heat source coolant in the heat exchanger, thereby controlling the temperature rise of the hydrogen. Acquire temperature control process data, and calculate the temperature heat loss coefficient based on the temperature control process data; The formula for calculating the temperature heat loss coefficient is as follows: Among them, K loss T is the temperature heat loss coefficient, β is the coefficient determined experimentally, and T e To preset the ideal hydrogen temperature, T a Q represents the actual hydrogen temperature. in The input system's heat ratio relative to a set value; Δt is the time interval, standardized to 1 or other fixed value; β is an adjustment value set according to experimental conditions. The temperature heat loss coefficient is compared with a preset heat loss threshold to obtain a loss comparison result; Calculate the temperature compensation adjustment coefficient based on the loss comparison results; The formula for calculating the temperature compensation adjustment coefficient is as follows: Among them, T kb K is the temperature compensation adjustment coefficient, α is the adjustment amplitude factor, and its value ranges from -1 to 1. yy The preset heat loss threshold; The temperature loss is compensated and adjusted according to the temperature compensation adjustment coefficient until the temperature heat loss coefficient is less than the preset heat loss threshold.

2. The fuel cell hydrogen cycle control method with active stack-in temperature control according to claim 1, characterized in that, S1 includes: The hydrogen pressure is reduced by a hydrogen pressure reducing valve, and the reduced hydrogen is then transferred to a shut-off valve through a hydrogen supply pipe; the shut-off valve is then activated to transfer the reduced hydrogen to a heat exchanger. High-temperature coolant is introduced into the heat exchanger via an auxiliary water pump. The high-temperature coolant is exchanged with the depressurized hydrogen in the heat exchanger to raise the temperature of the depressurized hydrogen and obtain heated hydrogen.

3. The fuel cell hydrogen cycle control method with active stack-in temperature control according to claim 1, characterized in that, S2 includes: After the heated hydrogen is regulated by the flow control valve, it forms a negative pressure through the nozzle of the ejector, and the negative pressure attracts the gas medium mixture and liquid water at the stack outlet, which is then transported to the gas-liquid separator along the recirculation pipeline. The gas-liquid separator separates liquid water from a gaseous medium mixture. The system receives control commands and controls the liquid water to be discharged through the drain valve and the nitrogen to be discharged through the nitrogen venting valve. The gas medium mixture participating in the recirculation is drawn into the ejector by negative pressure and mixed with the heated hydrogen before entering the reactor inlet.

4. The fuel cell hydrogen cycle control method with active stack-in temperature control according to claim 1, characterized in that, S3 includes: After the gas medium mixture is introduced into the stack, the feedback temperature data collected by the gas mixture temperature sensor is obtained. When the feedback temperature data is lower than the set value and the coolant outlet temperature is higher than the gas medium mixture inlet temperature, increase the speed of the heat exchanger auxiliary water pump so that the speed is less than or equal to the maximum operating speed. When the feedback temperature data collected by the gas-fuel mixture inlet temperature sensor is higher than the set value and the coolant outlet temperature is higher than the gas-fuel mixture inlet temperature, the speed of the heat exchanger auxiliary water pump is reduced, thereby reducing the flow rate of the high-temperature coolant flowing through the heat exchanger. The pressure difference between the infeed hydrogen pressure sensor and the outfeed pressure sensor is obtained, and the temperature rise rate of the mixed gas entering the reactor is adjusted according to the pressure difference.

5. The fuel cell hydrogen cycle control method with active stack-in temperature control according to claim 4, characterized in that, The step of acquiring the pressure difference between the infeed hydrogen pressure sensor and the recirculation outfeed pressure sensor, and adjusting the temperature rise rate of the mixed gas entering the reactor based on the pressure difference, includes: When the pressure difference between the infeed hydrogen pressure sensor and the outfeed pressure sensor is higher than the set value, reduce the speed of the heat exchanger auxiliary water pump to reduce the rate of temperature rise of the mixed gas entering the pile. When the pressure difference between the infeed hydrogen pressure sensor and the outfeed pressure sensor is lower than the set value, the speed of the heat exchanger auxiliary water pump is increased to increase the rate of temperature rise of the mixed gas entering the pile. The hydrogen inlet temperature is controlled by replacing the rotational speed of the auxiliary water pump of the heat exchanger with the opening degree of the water circuit back pressure valve.

6. A fuel cell hydrogen recirculation control system with active control of the stack feed temperature, characterized in that, The control system includes: The heat exchange module is used to transfer the coolant at the outlet of the high-temperature reactor coolant to the hot side of the heat exchanger, transfer the depressurized hydrogen to the cold side of the heat exchanger, and transfer the heat of the coolant to the depressurized hydrogen through the heat exchanger to raise the temperature of the depressurized hydrogen. The separation and transfer module is used to transfer the coolant that has completed heat exchange to the reactor coolant outlet circuit, and to transfer the heated hydrogen to the nozzle through the flow regulating valve and inject it into the ejector. The flow control module is used to control the flow of coolant from the hot side into the heat exchanger under the action of the coolant auxiliary water pump, and actively control the flow rate of coolant according to the target temperature value of the gas medium mixture entering the reactor. On the main circuit of the reactor coolant outlet, there is a throttling valve between the inlet and outlet of the heat exchanger coolant. The coolant in the main circuit of the reactor coolant outlet enters the heat exchanger. The flow resistance of the main circuit and the branch circuit is actively adjusted according to the target temperature value of the gas medium mixture entering the reactor, thereby controlling the flow rate of the coolant. The heat exchange capacity is controlled by adjusting the flow rate of the heat source coolant in the heat exchanger, thereby controlling the temperature rise of the hydrogen. Acquire temperature control process data, and calculate the temperature heat loss coefficient based on the temperature control process data; The formula for calculating the temperature heat loss coefficient is as follows: Among them, K loss T is the temperature heat loss coefficient, β is the coefficient determined experimentally, and T e To preset the ideal hydrogen temperature, T a Q represents the actual hydrogen temperature. in The input system's heat ratio relative to a set value; Δt is the time interval, standardized to 1 or other fixed value; β is an adjustment value set according to experimental conditions. The temperature heat loss coefficient is compared with a preset heat loss threshold to obtain a loss comparison result; Calculate the temperature compensation adjustment coefficient based on the loss comparison results; The formula for calculating the temperature compensation adjustment coefficient is as follows: Among them, T kb K is the temperature compensation adjustment coefficient, α is the adjustment amplitude factor, and its value ranges from -1 to 1. yy The preset heat loss threshold; The temperature loss is compensated and adjusted according to the temperature compensation adjustment coefficient until the temperature heat loss coefficient is less than the preset heat loss threshold.

7. The fuel cell hydrogen recirculation control system with active stack-in temperature control according to claim 6, characterized in that, The heat exchange module includes: The hydrogen pressure reducing module is used to reduce the pressure of hydrogen through a hydrogen pressure reducing valve, and then transmit the reduced hydrogen to the shut-off valve through a hydrogen supply pipe; it controls the shut-off valve to start, and then transmits the reduced hydrogen to the heat exchanger. Cooling water transfer module, used to introduce high-temperature coolant into the heat exchanger via an auxiliary water pump; The heat exchange module is used to exchange heat between the high-temperature coolant and the depressurized hydrogen in the heat exchanger, thereby increasing the temperature of the depressurized hydrogen to obtain heated hydrogen.

8. The fuel cell hydrogen recirculation control system with active stack-in temperature control according to claim 6, characterized in that, The separation transmission module includes: The hydrogen transfer module is used to adjust the heated hydrogen through the flow control valve, and then create a negative pressure through the nozzle of the ejector to obtain the gas medium mixture and liquid water attracted at the stack outlet under negative pressure, and transfer it to the gas-liquid separator along the recirculation pipeline. The gas-liquid separation module is used to separate liquid water and gaseous media mixtures in a gas-liquid separator; The ejector mixing module is used to acquire control commands and, according to the control commands, control the liquid water to be discharged through the drain valve and the nitrogen to be discharged through the nitrogen venting valve. The gas medium mixture participating in the recirculation is attracted into the ejector by negative pressure, and after mixing with the heated hydrogen, it enters the reactor inlet together.

9. The fuel cell hydrogen recirculation control system with active stack-entry temperature control according to claim 6, characterized in that, The flow control module includes: The feedback acquisition module is used to acquire the feedback temperature data collected by the gas mixture temperature sensor after the gas medium mixture enters the stack. The first speed increase module is used to increase the speed of the heat exchanger auxiliary water pump when the feedback temperature data is lower than the set value and the coolant outlet temperature is higher than the gas medium mixture inlet temperature, so that the speed is less than or equal to the maximum operating speed. The speed reduction module is used to reduce the speed of the heat exchanger auxiliary water pump when the feedback temperature data collected by the gas-fuel mixture inlet temperature sensor is higher than the set value and the coolant outlet temperature is higher than the gas-fuel mixture inlet temperature, thereby reducing the flow rate of the high-temperature coolant flowing through the heat exchanger. The rate control module is used to acquire the pressure difference between the infeed hydrogen pressure sensor and the recycle outlet pressure sensor, and adjust the temperature rise rate of the mixed gas entering the reactor based on the pressure difference.

10. The fuel cell hydrogen recirculation control system with active stack-entry temperature control according to claim 9, characterized in that, The rate control module includes: The rate reduction module is used to reduce the speed of the heat exchanger auxiliary water pump when the pressure difference between the inlet hydrogen pressure sensor and the outlet pressure sensor is higher than a set value, so as to reduce the rate of temperature rise of the mixed gas entering the pile. The rate boosting module is used to increase the speed of the heat exchanger auxiliary water pump when the pressure difference between the infeed hydrogen pressure sensor and the recirculation outlet pressure sensor is lower than a set value, so as to increase the rate of temperature rise of the mixed gas entering the pile. The water pump replacement module is used to replace the rotational speed of the heat exchanger auxiliary water pump with the opening degree of the water circuit back pressure valve, and also to control the hydrogen inlet temperature.

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