Method and apparatus for thermal management of a battery

Abstract

The present disclosure relates to a battery thermal management method and device, relates to the technical field of batteries, and is applied to a power generation system of a solid oxide fuel cell. The power generation system comprises an electric pile, a cathode heater, and a heat exchanger. The gas outlet of the cathode heater is connected with the cathode gas inlet of the electric pile. The gas outlet of the cold side of the heat exchanger is connected with the cathode input end of the electric pile. The cathode gas outlet of the electric pile is connected with the gas inlet of the hot side of the heat exchanger. The method comprises the following steps: in the case that the external load of the electric pile changes, according to the output voltage and output current of the electric pile, the input gas flow of the cathode heater and the heat exchanger is controlled according to a first flow distribution ratio. According to the operating temperature of the electric pile, the input gas flow of the cathode heater and the heat exchanger is controlled according to a second flow distribution ratio. According to the second flow distribution ratio and an initial flow distribution ratio, the output gas temperature of the cathode heater is adjusted. The present disclosure can improve the power generation efficiency and safety performance of the solid oxide fuel cell.

Description

Technical Field

[0001] This disclosure relates to the field of battery technology, and more specifically, to a thermal management method and apparatus for a battery. Background Technology

[0002] Solid oxide fuel cells (SOFCs) are a novel type of power generation device. Due to their high efficiency, pollution-free operation, all-solid-state structure, and wide adaptability to various fuel gases, they are widely used in fuel-powered applications. SOFC modules require a suitable temperature range to generate electricity stably; excessively high or low temperatures will affect power generation efficiency and may even damage the stack. However, after being loaded, changes in external load cause variations in the stack's own heat output, leading to the SOFC module's temperature exceeding its operating temperature range, thus impacting the power generation efficiency and safety performance of the SOFC. Summary of the Invention

[0003] The purpose of this disclosure is to provide a thermal management method and apparatus for batteries to improve the power generation efficiency of solid oxide fuel cells.

[0004] According to a first aspect of the present disclosure, a thermal management method for a battery is provided, applied to a power generation system of a solid oxide fuel cell. The power generation system includes: a fuel cell stack, a cathode heater, and a heat exchanger. The outlet of the cathode heater is connected to the cathode inlet of the fuel cell stack. The cold-side outlet of the heat exchanger is connected to the cathode input terminal of the fuel cell stack. The cathode outlet of the fuel cell stack is connected to the hot-side inlet of the heat exchanger. The method includes:

[0005] When the external load of the fuel cell changes, the input gas flow rate of the cathode heater and the heat exchanger is controlled according to the output voltage and output current of the fuel cell and in accordance with the first flow distribution ratio.

[0006] The input gas flow rates of the cathode heater and heat exchanger are controlled according to the operating temperature of the fuel cell stack and the second flow distribution ratio.

[0007] The output gas temperature of the cathode heater is adjusted according to the second flow distribution ratio and the initial flow distribution ratio.

[0008] Optionally, the method further includes:

[0009] Repeat the steps of controlling the input gas flow rate of the cathode heater and heat exchanger according to the second flow distribution ratio based on the operating temperature of the fuel cell stack, until the output gas temperature of the cathode heater is adjusted according to the second flow distribution ratio and the initial flow distribution ratio, until the operating temperature of the fuel cell stack is within the preset temperature range and the second flow distribution ratio is equal to the initial flow distribution ratio.

[0010] Optionally, the method further includes:

[0011] When the operating temperature of the fuel cell stack is not within the preset temperature range, the input gas flow rate of the cathode heater and the heat exchanger is controlled according to the operating temperature of the fuel cell stack and the third flow distribution ratio. The operating temperature of the fuel cell stack is the time average of the cathode inlet gas temperature and the cathode outlet gas temperature of the fuel cell stack.

[0012] The temperature of the output gas from the cathode heater is adjusted according to the third flow distribution ratio and the initial flow distribution ratio.

[0013] Optionally, controlling the input gas flow rate of the cathode heater and heat exchanger according to the output voltage and output current of the fuel cell stack and in accordance with the first flow rate distribution ratio includes:

[0014] The heat generation of the fuel cell is determined based on the output voltage and output current of the fuel cell.

[0015] The first flow distribution ratio is determined based on the heat generated by the fuel cell stack;

[0016] The input gas flow rates of the cathode heater and the heat exchanger are controlled according to the first flow distribution ratio.

[0017] Optionally, determining the first flow distribution ratio based on the heat generated by the fuel cell stack includes:

[0018] The heat to be adjusted of the fuel cell is determined based on the heat generated by the fuel cell, the first heat carried by the input gas of the fuel cell, the second heat carried by the output gas of the fuel cell, and the third heat radiated by the fuel cell.

[0019] The first flow distribution ratio is determined based on the heat to be adjusted.

[0020] Optionally, controlling the input gas flow rate of the cathode heater and heat exchanger according to the operating temperature of the fuel cell stack and the second flow distribution ratio includes:

[0021] The operating temperature of the fuel cell stack is determined based on the cathode inlet gas temperature and the cathode outlet gas temperature.

[0022] The second flow distribution ratio is determined based on the operating temperature of the fuel cell stack;

[0023] The input gas flow rate of the cathode heater and heat exchanger is controlled according to the second flow distribution ratio.

[0024] Optionally, determining the second flow distribution ratio based on the operating temperature of the fuel cell stack includes:

[0025] The time-averaged average of the first heat carried by the cathode input gas and the second heat carried by the cathode output gas of the fuel cell stack is taken as the operating temperature of the fuel cell stack.

[0026] The second flow distribution ratio is determined based on the operating temperature of the fuel cell stack and the preset target operating temperature.

[0027] Optionally, adjusting the temperature of the output gas of the cathode heater according to the second flow distribution ratio and the initial flow distribution ratio includes:

[0028] When the cathode heater is an electric heater and the second flow distribution ratio is not the initial flow distribution ratio, the heating power of the electric heater is adjusted to adjust the temperature of the output gas of the cathode heater.

[0029] When the cathode heater is a burner and the second flow distribution ratio is not the initial flow distribution ratio, the fuel input of the burner is adjusted to adjust the temperature of the output gas of the cathode heater.

[0030] According to a second aspect of the present disclosure, a thermal management device for a battery is provided, applied to a power generation system of a solid oxide fuel cell. The power generation system includes: a fuel cell stack, a cathode heater, and a heat exchanger. The outlet of the cathode heater is connected to the cathode inlet of the fuel cell stack. The cold-side outlet of the heat exchanger is connected to the cathode input terminal of the fuel cell stack. The cathode outlet of the fuel cell stack is connected to the hot-side inlet of the heat exchanger. The device includes:

[0031] The first control module is used to control the input gas flow rate of the cathode heater and the heat exchanger according to the output voltage and output current of the fuel cell stack and a first flow distribution ratio when the external load of the fuel cell stack changes.

[0032] The second control module is used to control the input gas flow rate of the cathode heater and the heat exchanger according to the operating temperature of the fuel cell stack and the second flow distribution ratio.

[0033] The adjustment module is used to adjust the output gas temperature of the cathode heater according to the second flow distribution ratio and the initial flow distribution ratio.

[0034] Optionally, the device further includes:

[0035] The repetitive execution module is used to repeatedly execute the steps of controlling the input gas flow rate of the cathode heater and the heat exchanger according to the second flow distribution ratio based on the operating temperature of the fuel cell stack, and adjusting the output gas temperature of the cathode heater according to the second flow distribution ratio and the initial flow distribution ratio, until the operating temperature of the fuel cell stack is within a preset temperature range and the second flow distribution ratio is equal to the initial flow distribution ratio.

[0036] Optionally, the second control module is further configured to:

[0037] When the operating temperature of the fuel cell stack is not within the preset temperature range, the input gas flow rate of the cathode heater and the heat exchanger is controlled according to the operating temperature of the fuel cell stack and the third flow distribution ratio. The operating temperature of the fuel cell stack is the time average of the cathode inlet gas temperature and the cathode outlet gas temperature of the fuel cell stack.

[0038] The adjustment module is also used to adjust the temperature of the output gas of the cathode heater according to the third flow distribution ratio and the initial flow distribution ratio.

[0039] Optionally, the first control module is used to:

[0040] The heat generation of the fuel cell is determined based on the output voltage and output current of the fuel cell.

[0041] The first flow distribution ratio is determined based on the heat generated by the fuel cell stack;

[0042] The input gas flow rates of the cathode heater and the heat exchanger are controlled according to the first flow distribution ratio.

[0043] Optionally, the first control module is used to:

[0044] The heat to be adjusted of the fuel cell is determined based on the heat generated by the fuel cell, the first heat carried by the input gas of the fuel cell, the second heat carried by the output gas of the fuel cell, and the third heat radiated by the fuel cell.

[0045] The first flow distribution ratio is determined based on the heat to be adjusted.

[0046] Optionally, the second control module is used for:

[0047] The operating temperature of the fuel cell stack is determined based on the cathode inlet gas temperature and the cathode outlet gas temperature.

[0048] The second flow distribution ratio is determined based on the operating temperature of the fuel cell stack;

[0049] The input gas flow rate of the cathode heater and heat exchanger is controlled according to the second flow distribution ratio.

[0050] Optionally, the second control module is used for:

[0051] The time-averaged average of the first heat carried by the cathode input gas and the second heat carried by the cathode output gas of the fuel cell stack is taken as the operating temperature of the fuel cell stack.

[0052] The second flow distribution ratio is determined based on the operating temperature of the fuel cell stack and the preset target operating temperature.

[0053] Optionally, the adjustment module is used for:

[0054] When the cathode heater is an electric heater and the second flow distribution ratio is not the initial flow distribution ratio, the heating power of the electric heater is adjusted to adjust the temperature of the output gas of the cathode heater.

[0055] When the cathode heater is a burner and the second flow distribution ratio is not the initial flow distribution ratio, the fuel input of the burner is adjusted to adjust the temperature of the output gas of the cathode heater.

[0056] The present invention, through the above technical solution, is applied to a power generation system for a solid oxide fuel cell, comprising a fuel cell stack, a cathode heater, and a heat exchanger. The method first controls the input gas flow rates of the cathode heater and heat exchanger according to a first flow distribution ratio based on the output voltage and current of the fuel cell stack when the external load of the fuel cell stack changes. Then, based on the operating temperature of the fuel cell stack, it controls the input gas flow rates of the cathode heater and heat exchanger according to a second flow distribution ratio. Finally, it adjusts the output gas temperature of the cathode heater based on the second flow distribution ratio and the initial flow distribution ratio. By adjusting the input gas flow rates of the cathode heater and heat exchanger sequentially according to the output power and operating temperature of the fuel cell stack when the external load of the fuel cell stack changes, this invention ensures that the temperature of the fuel cell stack remains within a suitable operating temperature range, thereby improving the power generation efficiency and safety performance of the solid oxide fuel cell.

[0057] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0058] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:

[0059] Figure 1 This is a flowchart illustrating a thermal management method for a battery according to an exemplary embodiment;

[0060] Figure 2 It is based on Figure 1 A schematic diagram of a power generation system using a solid oxide fuel cell is shown in the embodiment.

[0061] Figure 3 It is based on Figure 1 A schematic diagram of another power generation system using a solid oxide fuel cell is shown in the embodiment;

[0062] Figure 4 This is a flowchart illustrating another thermal management method for a battery according to an exemplary embodiment;

[0063] Figure 5 This is a flowchart illustrating another thermal management method for a battery according to an exemplary embodiment;

[0064] Figure 6 This is a flowchart illustrating another thermal management method for a battery according to an exemplary embodiment;

[0065] Figure 7 This is a flowchart illustrating another thermal management method for a battery according to an exemplary embodiment;

[0066] Figure 8 This is a flowchart illustrating another thermal management method for a battery according to an exemplary embodiment;

[0067] Figure 9 This is a block diagram illustrating a thermal management device for a battery according to an exemplary embodiment;

[0068] Figure 10 This is a block diagram illustrating another thermal management device for a battery according to an exemplary embodiment. Detailed Implementation

[0069] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0070] Figure 1 This is a flowchart illustrating a thermal management method for a battery according to an exemplary embodiment, such as... Figure 1 As shown, a power generation system applied to a solid oxide fuel cell includes a fuel cell stack, a cathode heater, and a heat exchanger. The outlet of the cathode heater is connected to the cathode inlet of the fuel cell stack, the cold-side outlet of the heat exchanger is connected to the cathode input terminal of the fuel cell stack, and the cathode outlet of the fuel cell stack is connected to the hot-side inlet of the heat exchanger. The method includes:

[0071] Step 101: When the external load of the fuel cell changes, the input gas flow rate of the cathode heater and the heat exchanger is controlled according to the first flow distribution ratio based on the output voltage and output current of the fuel cell.

[0072] For example, an application scenario of this disclosure could be a power generation system for a solid oxide fuel cell. This system could include a fuel cell stack, a cathode heater, and a heat exchanger. The outlet of the cathode heater is connected to the cathode inlet of the fuel cell stack. The cold-side outlet of the heat exchanger is connected to the cathode input of the fuel cell stack, and the cathode outlet of the fuel cell stack is connected to the hot-side inlet of the heat exchanger. Here, the fuel cell stack refers to a solid oxide fuel cell stack. There can be one or more fuel cell stacks, which can be connected in series or parallel to form a stack tower. For example, four fuel cell stacks can be connected in series, with their respective gas paths connected in parallel to form a stack tower. The feed gas for the fuel cell stack is hydrogen, and the cathode gas is air. The anode and cathode of the fuel cell stack are connected to a DC electronic load as an external load to consume the electrical energy generated by the fuel cell stack. The cathode heater can be a cathode electric heater or a burner. Figure 2 This is a schematic diagram of a power generation system where the cathode heater is an electric cathode heater. Figure 3 This is a schematic diagram of a power generation system with a cathode heater as the burner. The heat exchanger is a device that facilitates heat exchange between the cathode intake and exhaust of the fuel cell stack. In this case, a plate heat exchanger is used, which offers high heat exchange efficiency and a compact structure. The heat exchanger is arranged in a counter-current manner, with the cold side being the cathode intake (lower temperature) and the hot side being the cathode exhaust (higher temperature). This power generation system may also include: an anode heat exchanger, a cathode induced draft fan, an anode induced draft fan, a water cooler, and other equipment.

[0073] The power generation system also includes a PLC (Programmable Logic Controller), a host computer, temperature sensors, flow sensors, current sensors, and pressure sensors. The PLC receives data signals from the temperature, flow, current, and pressure sensors and outputs control signals to the electric heater power controller and the air or gas flow controller. The host computer monitors the operating status of the power generation system and can generate control signals based on the real-time acquired signals by writing control programs. These programs are then transmitted down the data bus to the PLC controller, which in turn outputs control signals to the various devices. The data bus can be MODBUS-TCP or any other type supported by the host computer and PLC controller.

[0074] The fuel cell stack generates electrical and thermal energy through electrochemical reactions. The electrical energy is used to supply the external load, while the thermal energy raises the temperature of the stack itself and the cathode / anode gases. The electrical and thermal energy generated by the stack are positively correlated. With a fixed fuel input, the heat generation of the stack increases or decreases with the increase or decrease of the external load. Therefore, the heat generation of the stack can be obtained by measuring its output current and output voltage. A first flow distribution ratio can then be determined based on the heat generation of the stack, and the input gas flow rates of the cathode heater and heat exchanger can be controlled according to this ratio.

[0075] Step 102: Control the input gas flow rate of the cathode heater and heat exchanger according to the second flow distribution ratio based on the operating temperature of the fuel cell stack.

[0076] Step 103: Adjust the output gas temperature of the cathode heater according to the second flow distribution ratio and the initial flow distribution ratio.

[0077] Reference Figure 2 or Figure 3 The solid oxide fuel cell power generation system shown incorporates closed-loop control based on the stack operating temperature in its control logic loop to further improve control accuracy and robustness. When the stack operating temperature deviates from the set temperature, causing it to fall outside the preset temperature range, the operating temperature can be adjusted using closed-loop control. In some embodiments, a third flow distribution ratio can be determined based on the stack operating temperature, and the input gas flow rates of the cathode heater and heat exchanger can be controlled according to this ratio. In one implementation, the third flow distribution ratio can be calculated based on the stack operating temperature and a preset target operating temperature, ensuring that the input gas temperatures of the cathode heater and heat exchanger, distributed according to this ratio, allow the stack operating temperature to reach the preset target operating temperature.

[0078] After adjusting the input gas flow rates of the cathode heater and heat exchanger according to the second flow distribution ratio, the change in the flow distribution ratio will cause a change in the cold-side outlet temperature of the heat exchanger, resulting in the cathode input gas temperature of the fuel cell stack deviating from the preset temperature. Furthermore, the flow distribution ratio will not be the initial flow distribution ratio, affecting the economic operation of the power generation system. Therefore, adjusting the output gas temperature of the cathode heater can restore the initial flow distribution ratio by changing the flow distribution ratio of the input gas to the cathode heater and the heat exchanger.

[0079] In summary, this disclosure applies to a power generation system for solid oxide fuel cells, which includes a fuel cell stack, a cathode heater, and a heat exchanger. The method first controls the input gas flow rates of the cathode heater and heat exchanger according to a first flow distribution ratio based on the output voltage and current of the fuel cell stack when the external load on the stack changes. Then, based on the operating temperature of the fuel cell stack, it controls the input gas flow rates of the cathode heater and heat exchanger according to a second flow distribution ratio. Finally, it adjusts the output gas temperature of the cathode heater based on the second flow distribution ratio and the initial flow distribution ratio. This disclosure, by adjusting the input gas flow rates of the cathode heater and heat exchanger sequentially based on the output power and operating temperature of the fuel cell stack when the external load on the fuel cell stack changes, ensures that the temperature of the fuel cell stack remains within a suitable operating temperature range, thereby improving the power generation efficiency and safety performance of the solid oxide fuel cell.

[0080] Figure 4 This is a flowchart illustrating another battery thermal management method according to an exemplary embodiment, such as... Figure 4 As shown, the method also includes:

[0081] Step 104: Repeat the steps of controlling the input gas flow rate of the cathode heater and heat exchanger according to the second flow distribution ratio based on the operating temperature of the fuel cell stack, and adjusting the output gas temperature of the cathode heater according to the second flow distribution ratio and the initial flow distribution ratio, until the operating temperature of the fuel cell stack is within the preset temperature range and the second flow distribution ratio is equal to the initial flow distribution ratio.

[0082] For example, during the normal operation of the fuel cell stack, as the load changes, the heat generated by the stack itself changes, causing the stack to deviate from the set temperature. However, due to the large heat capacity of the stack, the delay between adjusting the load and the start of temperature change is significant. This disclosure uses open-loop control logic based on the stack's heat generation to achieve proactive regulation; however, open-loop control suffers from inaccurate adjustments. Therefore, closed-loop control logic is superimposed in the control loop, repeatedly executing steps 102 to 103 until the stack's operating temperature is within the preset temperature range and the second flow distribution ratio equals the initial flow distribution ratio. This dual control approach balances dynamic and static performance, resulting in high control efficiency, good economy, and precise control of the stack's operating temperature.

[0083] like Figure 2As shown, taking the cathode heater as an example, the cathode electric heater can be a 10kW gas electric heater with adjustable heating power. The temperature sensor can be a type K thermocouple, with measurement points including the cathode electric heater outlet gas temperature TE01, the fuel cell cathode inlet gas temperature TE02, and the fuel cell cathode outlet gas temperature TE03. FV01 is a flow meter for monitoring and controlling the inlet gas flow of the cathode electric heater, and FV02 is a flow meter for monitoring and controlling the cold side inlet gas flow of the heat exchanger. The current sensor PA01 and voltage sensor PV01 are integrated into the DC electronic load. The PLC controller receives data signals from the temperature sensor, flow sensor, current sensor, and pressure sensor via a wired connection and can output control signals to the cathode electric heater and the flow controller. The host computer is connected to the PLC controller via a data bus using the MODBUS communication protocol and TCP / IP Ethernet as the data carrier. The PLC controller and the host computer exchange data using the MODBUS-TCP protocol. In the instrument measurement and control device, the K-type thermocouple, flow meter, current sensor and voltage sensor in the DC electronic load can transmit analog signals to the PLC controller through signal lines. The PLC controller can then transmit analog control signals to the flow meter and cathode electric heater through signal lines.

[0084] In this embodiment, during the normal operation of the fuel cell stack, the DC electronic load increases the electrical load, leading to increased power generation and heat generation, and a rise in the stack's operating temperature. Current sensor PA01 and voltage sensor PV01 transmit signals to the PLC and host computer. The host computer detects the increased electrical load and calculates the stack's heat generation based on PA01 and PV01. The host computer compares the heat generation before and after the electrical load adjustment to calculate the heat generation increment. This increment is sent to the flow controller 2, which then calculates a new distribution ratio between the cathode heater flow rate FV01 and the cathode heat exchanger flow rate FV02 based on the current cathode heater outlet temperature TE01, stack inlet temperature TE02, cathode heater flow rate FV01, and cathode heat exchanger cold side flow rate FV02. If the cathode heater outlet temperature is higher than the cathode heat exchanger cold side outlet temperature, the cathode heat exchanger flow rate FV02 is increased while the cathode heater flow rate FV01 is correspondingly decreased, thus lowering the stack cathode inlet temperature TE02 and preventing a rapid increase in stack temperature; conversely, the opposite is true. The host computer transmits the flow control signal to the PLC, and the PLC sends instructions to the flow meter to control the flow rate change.

[0085] In this embodiment, the closed-loop control logic for the thermal management of the power generation module is as follows: the host computer calculates and monitors the hourly average temperature of the gas at the cathode inlet and outlet of the fuel cell stack (i.e., the fuel cell stack operating temperature) in real time. If the fuel cell stack operating temperature exceeds 750±5℃, the host computer starts to adjust the distribution ratio of the cathode electric heater flow rate FV01 and the cathode heat exchanger flow rate FV02, as well as the cathode electric heater outlet temperature TE01. If the fuel cell stack operating temperature is 760℃, the host computer will calculate that the difference between the set temperature of 750℃ and the actual temperature of 760℃ is 10℃. The flow controller in the host computer calculates a new flow distribution ratio based on the 10℃ temperature difference, the cathode electric heater outlet temperature TE01, the fuel cell stack inlet temperature TE02, the cathode electric heater flow rate FV01, and the cathode heat exchanger cold side flow rate FV02. If the cathode electric heater outlet temperature is higher than the cathode heat exchanger cold side outlet temperature, the cathode heat exchanger flow rate FV02 is increased and the cathode electric heater flow rate FV01 is correspondingly decreased, thereby reducing the fuel cell stack cathode inlet temperature TE02, and vice versa. The host computer transmits the flow control signal to the PLC, and the PLC sends instructions to the flow meter to control the flow rate. By mixing two gases at different temperatures, the temperature of the fuel cell stack is kept within the initially set temperature range.

[0086] Meanwhile, in the host computer, the output of flow controller 1 serves as the input of the temperature controller, whose output deviates from the initial flow distribution setting. The temperature controller calculates the adjustment amount for the cathode electric heater outlet temperature TE01 based on the degree of deviation. The host computer transmits the control signal to the PLC, which adjusts the cathode electric heater power, causing a corresponding change in the cathode electric heater outlet temperature TE01. This finely adjusts the temperature TE02 of the mixed gas at the heater outlet and the cold side outlet of the heat exchanger, restoring the flow distribution to the set value. In the closed-loop control, the PLC uses a proportional-integral (PI) combined regulation method when controlling the cathode electric heater power.

[0087] In this embodiment, the system sampling average period T can be set first. The value of T can be obtained through system debugging, for example, it can be 10s. The steady-state operating temperature of the fuel cell stack can be 750℃, and the heat dissipation of the fuel cell stack can be 1kW, where the heat dissipation of the fuel cell stack is a constant value and is only related to the set value of the fuel cell stack operating temperature. To prevent the electric heater from dry burning, the air flow rate of the electric heater is not less than 5m³ / h. 3 / h.

[0088] In this embodiment, the flow controller acts as the main controller, and a controller with proportional-integral (PI) control is selected. Then, the temperature controller is set to automatic mode as the secondary controller, also using PI control. Specific PID control parameters are determined through system debugging. During the operation of the thermal management control system, in each sampling cycle, the host computer calculates the time-averaged values ​​of the fuel cell cathode inlet temperature TE02 and the fuel cell cathode outlet temperature TE03. When these values ​​are within the set value of 750±5℃, monitoring for the next cycle begins. If the condition is not met, the flow controller in the host computer calculates the adjustment amount based on the deviation between the measured time-averaged temperature of the fuel cell cathode inlet and outlet gases and the set temperature of 750℃. This changes the gas flow distribution ratio between the cathode electric heater and the heat exchanger, adjusting the amount of gas mixed at different temperatures to regulate the fuel cell cathode inlet temperature, thereby restoring the time-averaged temperature of the fuel cell cathode inlet and outlet gases to the normal range.

[0089] Adjusting the gas flow distribution ratio between the cathode electric heater and the heat exchanger reduces the overall thermal efficiency of the system. A deviation exists between the time-averaged temperatures of the gas at the cathode inlet and outlet of the fuel cell stack and the set temperature of 750℃, indicating a deviation in the cathode electric heater outlet temperature. Therefore, the output value of the flow controller is input to the temperature controller, and the difference between the flow controller's output value and the set flow distribution ratio is used to calculate the adjustment value for the cathode electric heater outlet temperature. By changing the power of the cathode electric heater, the fuel cell stack cathode inlet temperature is adjusted—a slow process. Simultaneously, the host computer monitors the fuel cell stack's power generation load changes in real time. Based on signals from the current and voltage sensors, the host computer calculates the fuel cell stack's heat generation, and then uses the heat dissipation of the fuel cell stack and the heat generation from the previous stage to calculate the heat that the system needs to replenish or dissipate. The control signal is transmitted to the flow controller to adjust the gas flow distribution ratio between the electric heater and the heat exchanger, thereby adjusting the fuel cell stack operating temperature.

[0090] like Figure 3As shown, taking the cathode heater as an example, the burner is a gas burner using natural gas as fuel, and the heating power can be adjusted by regulating the gas flow rate. In this case, the instrumentation and control device includes temperature sensors, flow measurement / control devices, current sensors, voltage sensors, a PLC controller, and a host computer. The temperature sensors are K-type thermocouples, measuring the burner outlet gas temperature TE01, the fuel cell cathode inlet gas temperature TE02, and the fuel cell cathode outlet gas temperature TE03. FV01 is a flow meter for monitoring and controlling the burner inlet gas flow rate, FV02 is a flow meter for monitoring and controlling the heat exchanger cold side inlet gas flow rate, and FV03 is a flow meter for monitoring and controlling the natural gas flow rate entering the burner. The current sensor PA01 and the voltage sensor PV01 are integrated into a DC electronic load. The PLC controller receives data signals from the temperature, flow, current, and pressure sensors via a wired connection and can output control signals to the flow controllers of the burner and heat exchanger. The host computer is connected to the Siemens PLC control system via a data bus. The communication protocol of the data bus is MODBUS, and the data carrier is TCP / IP Ethernet.

[0091] The connections between the components are as follows: cathode gas enters the power generation module via two paths: one path enters the cold side of the heat exchanger; the other path enters the burner. These two gas paths mix and then enter the fuel cell stack. The high-temperature exhaust from the stack enters the hot side of the heat exchanger to heat the gas on the cold side. In the instrumentation and control device, the K-type thermocouple, flow meter, and current and voltage sensors in the DC electronic load transmit analog signals to the PLC controller via signal lines. The PLC controller then transmits analog control signals to the flow meter via signal lines. Data exchange between the PLC controller and the host computer is achieved using the MODBUS-TCP protocol.

[0092] In this embodiment, during the normal operation of the fuel cell stack, the DC electronic load increases the electrical load, leading to increased power generation and heat generation, and a rise in the stack's operating temperature. Current sensor PA01 and voltage sensor PV01 transmit signals to the PLC and host computer. The host computer detects the increased electrical load and calculates the stack's heat generation based on PA01 and PV01. The host computer compares the heat generation before and after the electrical load adjustment to calculate the heat generation increment. This increment is sent to the flow controller 2, which then calculates a new distribution ratio between the burner air flow rate FV01 and the cathode heat exchanger flow rate FV02 based on the current burner outlet temperature TE01, stack inlet temperature TE02, burner air flow rate FV01, and cathode heat exchanger cold side flow rate FV02. If the burner outlet temperature is higher than the cathode heat exchanger cold side outlet temperature, the cathode heat exchanger flow rate FV02 is increased while the burner flow rate FV01 is correspondingly decreased, thus lowering the stack cathode inlet temperature TE02 and preventing a rapid increase in stack temperature; conversely, the opposite is true. The host computer transmits the flow control signal to the PLC, and the PLC sends instructions to the flow meter to control the flow rate change.

[0093] In this embodiment, the closed-loop control logic for the thermal management of the power generation module is as follows: the host computer calculates and monitors the hourly average temperature of the gas at the cathode inlet and outlet of the fuel cell stack (i.e., the fuel cell stack operating temperature) in real time. If the fuel cell stack operating temperature exceeds 750±5℃, the host computer starts to adjust the distribution ratio of the burner air flow rate FV01 and the cathode heat exchanger flow rate FV02, as well as the burner outlet temperature TE01. If the actual operating temperature of the fuel cell stack is 760℃, the host computer will calculate that the difference between the set temperature of 750℃ and the actual temperature of 760℃ is 10℃. The flow controller in the host computer calculates a new flow distribution ratio based on the 10℃ temperature difference, the burner outlet temperature TE01, the fuel cell stack inlet temperature TE02, the burner air flow rate FV01, and the cathode heat exchanger cold side flow rate FV02. If the burner outlet temperature is higher than the cathode heat exchanger cold side outlet temperature, the cathode heat exchanger flow rate FV02 is increased and the burner flow rate FV01 is correspondingly decreased, thereby reducing the fuel cell stack cathode inlet temperature TE02, and vice versa. The host computer transmits the flow control signal to the PLC, and the PLC sends instructions to the flow meter to control the flow rate. By mixing two gases at different temperatures, the temperature of the fuel cell stack is kept within the initially set temperature range.

[0094] Meanwhile, in the host computer, the output of flow controller 1 serves as the input of the temperature controller, whose output deviates from the initial flow distribution setting. The temperature controller calculates the adjustment amount for the burner outlet temperature TE01 based on the degree of deviation. The host computer transmits the control signal to the PLC, which adjusts the flow rate of the gas supplied to the burner, causing a corresponding change in the burner outlet temperature TE01. This finely adjusts the temperature TE02 of the mixed gas at the burner outlet and the cold side outlet of the heat exchanger, restoring the flow distribution to the set value. In this closed-loop control, the PLC employs a proportional-integral (PI) regulation method when controlling the burner gas flow rate.

[0095] In this embodiment, the temperature of the gas mixture is the cathode inlet temperature TE02 of the fuel cell stack. The gas is heated by the fuel cell stack and the temperature at which it exits the fuel cell stack is the cathode outlet temperature TE03. The time-averaged values ​​of the cathode inlet and outlet temperatures are negatively fed back to the flow controller of the host computer. This process is repeated to achieve closed-loop precise regulation.

[0096] In this embodiment, the system sampling average period T is first set. The value of T is obtained based on system debugging, and in this case, it is set to 10s. The steady-state operating temperature of the fuel cell stack can be 750℃, and the heat dissipation of the fuel cell stack is 1kW. To prevent the burner from dry burning, the air flow rate of the burner is not less than 5m3 / h.

[0097] In this embodiment, the flow controller acts as the main controller, and a controller with proportional-integral (PI) control is selected. Then, the temperature controller is set to automatic mode as the secondary controller, also using PI control. The specific PID control parameters are determined through system debugging. During the operation of the thermal management control system, within each 10-second sampling cycle, the host computer calculates the time-averaged values ​​of the fuel cell cathode inlet temperature TE02 and the fuel cell cathode outlet temperature TE03. If these values ​​are within the set value of 750±5℃, the next monitoring cycle begins. If the condition is not met, the flow controller in the host computer calculates the adjustment amount based on the deviation between the measured time-averaged temperature of the fuel cell cathode inlet and outlet gases and the set temperature of 750℃. This changes the gas flow distribution ratio between the burner and the heat exchanger, adjusting the amount of gas mixed at different temperatures to regulate the fuel cell cathode inlet temperature, thereby restoring the time-averaged temperature of the fuel cell cathode inlet and outlet gases to the normal range.

[0098] Adjusting the gas flow distribution ratio between the burner and heat exchanger reduces the overall thermal efficiency of the system. A deviation exists between the time-averaged temperatures of the gas at the cathode inlet and outlet of the fuel cell stack and the set temperature of 750℃, indicating a deviation in the burner outlet temperature. Therefore, the output value of the flow controller is input to the temperature controller, and the burner outlet temperature adjustment value is calculated based on the difference between the flow controller's output value and the set flow distribution ratio. By changing the burner power, the cathode inlet temperature of the fuel cell stack is adjusted—a slow process. Simultaneously, the host computer monitors changes in the fuel cell stack's power generation load in real time. Based on signals from current and voltage sensors, the host computer calculates the heat generated by the fuel cell stack, and then calculates the heat that the system needs to replenish or remove based on the heat dissipation of the fuel cell stack and the heat generated in the previous stage. The control signal is transmitted to the flow controller to adjust the gas flow distribution ratio between the burner and heat exchanger, thereby adjusting the fuel cell stack operating temperature.

[0099] Figure 5 This is a flowchart illustrating another battery thermal management method according to an exemplary embodiment, such as... Figure 5 As shown, the method also includes:

[0100] Step 105: When the operating temperature of the fuel cell stack is not within the preset temperature range, the input gas flow rate of the cathode heater and the heat exchanger is controlled according to the third flow distribution ratio based on the operating temperature of the fuel cell stack. The operating temperature of the fuel cell stack is the time average of the cathode inlet gas temperature and the cathode outlet gas temperature.

[0101] Step 106: Adjust the temperature of the output gas of the cathode heater according to the third flow distribution ratio and the initial flow distribution ratio.

[0102] For example, if the external load on the fuel cell stack remains unchanged, but the stack's operating temperature is outside the preset temperature range, the operating temperature can be adjusted using closed-loop control. The preset temperature range is the suitable operating temperature range for fuel cell power generation. In some embodiments, a third flow distribution ratio can be determined based on the stack's operating temperature, and the input gas flow rates of the cathode heater and heat exchanger can be controlled according to this ratio. In one implementation, the third flow distribution ratio can be calculated based on the stack's operating temperature and a preset target operating temperature, such that the temperature of the input gas to the cathode heater and heat exchanger, distributed according to the third flow distribution ratio, ensures that the stack's operating temperature reaches the preset target operating temperature.

[0103] After adjusting the input gas flow rates of the cathode heater and heat exchanger according to the third flow distribution ratio, the change in the flow distribution ratio will cause a change in the cold-side outlet temperature of the heat exchanger, resulting in the cathode input gas temperature of the fuel cell stack deviating from the preset temperature. Furthermore, the flow distribution ratio will not be the initial flow distribution ratio, affecting the economic operation of the power generation system. Therefore, adjusting the output gas temperature of the cathode heater can restore the initial flow distribution ratio by changing the flow distribution ratio of the input gas to the cathode heater and the heat exchanger.

[0104] Figure 6 This is a flowchart illustrating another battery thermal management method according to an exemplary embodiment, such as... Figure 6 As shown, step 101 can be achieved through the following steps:

[0105] Step 1011: Determine the heat generation of the fuel cell stack based on its output voltage and output current.

[0106] Step 1012: Determine the first flow distribution ratio based on the heat generated by the fuel cell stack.

[0107] Step 1013: Control the input gas flow rate of the cathode heater and the heat exchanger according to the first flow distribution ratio.

[0108] In one application scenario, step 1012 can be implemented as follows:

[0109] The heat to be adjusted in the fuel cell is determined based on the heat generated by the fuel cell, the first heat carried by the input gas of the fuel cell, the second heat carried by the output gas of the fuel cell, and the third heat radiated by the fuel cell.

[0110] Determine the first flow rate allocation ratio based on the heat to be adjusted.

[0111] For example, a fuel cell stack generates electrical and thermal energy through electrochemical reactions. The electrical energy is used to supply an external load, while the thermal energy raises the temperature of the stack itself and the cathode / anode gases. The electrical and thermal energy generated by the stack are positively correlated. With a fixed fuel input, the heat generation of the stack increases or decreases with the increase or decrease of the external load. Therefore, the heat generation of the stack can be obtained by measuring its output current and output voltage. The heat generation of the stack can be calculated using Equation 1.

[0112]

[0113] Where E is the heat generated by the fuel cell stack; N is the total number of solar cells in the fuel cell stack; q r I is the calorific value of the fuel; U is the output current of the fuel cell stack; e is the output voltage of the fuel cell stack; e = 1.602 * 10 -19 N A N is Avogadro's constant.A =6.02*10 23 .

[0114] Maintaining a stable fuel cell stack operating temperature hinges on maintaining the thermal balance of the power generation module. The heat sources of the fuel cell stack are its own heat generation and the heat carried by the gas entering the stack's cathode. Heat loss occurs through the heat carried away by the exhaust gas from the stack's cathode and the heat dissipated to the surrounding environment through radiation or convection. A stable operating temperature can only be maintained when the heat generated by the fuel cell stack and the first heat carried by the input gas equal the second heat carried by the output gas and the third heat radiated by the stack. Changes in the external load of the fuel cell stack will alter its heat generation, necessitating adjustments to the heat carried by the input gas to ensure a stable operating temperature. In some embodiments, the heat to be adjusted can be determined based on the heat generated by the fuel cell stack, the first heat carried by the input gas, the second heat carried by the output gas, and the third heat radiated by the stack. This adjusted heat indicates the amount of adjustment required for the first heat carried by the input gas. After obtaining the temperature of the input gas and the output gas of the fuel cell from the temperature sensor, and the flow rate of the input gas and the output gas of the fuel cell from the flow sensor, the first heat carried by the input gas and the second heat carried by the output gas of the fuel cell can be obtained according to Formula 2. The third heat radiated by the fuel cell is a constant and can be obtained by process simulation calculation or early debugging.

[0115] Q g =qh(T)(Formula 2)

[0116] Among them, Q g q represents the heat carried by the gas, q represents the gas flow rate (kg / h), and h(T) represents the enthalpy of the gas (air) at temperature T (kJ / kg).

[0117] If the heat generation of the fuel cell stack increases, the heat to be adjusted indicator decreases the initial heat carried by the input gas to maintain the operating temperature of the fuel cell stack. Conversely, if the heat generation of the fuel cell stack decreases, the heat to be adjusted indicator increases the initial heat carried by the input gas to maintain the operating temperature of the fuel cell stack. In one implementation, since the input gas to the cathode heater and the input gas to the heat exchanger have different temperatures, i.e., equal amounts of gas carry different amounts of heat, the initial flow distribution ratio can be determined based on the heat to be adjusted. This means that the initial heat carried by the input gas to the fuel cell stack is adjusted by changing the ratio of the input gas flow rates to the cathode heater and the heat exchanger, thus keeping the operating temperature of the fuel cell stack constant. By adjusting the mixing ratio of two gases at different temperatures, the heat carried by the input gas to the fuel cell cathode can be adjusted, allowing the operating temperature of the fuel cell stack to be corrected before the stack temperature changes.

[0118] Figure 7 This is a flowchart illustrating another battery thermal management method according to an exemplary embodiment, such as... Figure 7 As shown, step 102 can be achieved through the following steps:

[0119] Step 1021: Determine the operating temperature of the fuel cell stack based on the cathode inlet gas temperature and cathode outlet gas temperature.

[0120] Step 1022: Determine the second flow distribution ratio based on the operating temperature of the fuel cell stack.

[0121] Step 1023: Control the input gas flow rate of the cathode heater and heat exchanger according to the second flow distribution ratio.

[0122] In another application scenario, one implementation of step 1022 can be:

[0123] The time-averaged values ​​of the temperature of the gas input to the cathode and the temperature of the gas output to the cathode of the fuel cell stack are taken as the operating temperature of the fuel cell stack.

[0124] The second flow distribution ratio is determined based on the operating temperature of the fuel cell stack and the preset target operating temperature.

[0125] For example, the temperature of the cathode output gas of the fuel cell stack can be acquired in real time using temperature sensor TE01, and the temperature of the cathode input gas of the fuel cell stack can be acquired in real time using temperature sensor TE02. The time-averaged values ​​of the cathode input gas temperature and the cathode output gas temperature of the fuel cell stack are used as the operating temperature of the fuel cell stack. When the fuel cell stack temperature deviates from the preset temperature range, a second flow distribution ratio can be determined based on the fuel cell stack operating temperature, and the input gas flow rates of the cathode heater and heat exchanger can be controlled according to the second flow distribution ratio. In one implementation, the second flow distribution ratio can be calculated based on the fuel cell stack operating temperature and the preset target operating temperature, so that the input gas temperatures of the cathode heater and heat exchanger distributed according to the second flow distribution ratio can ensure that the fuel cell stack operating temperature reaches the preset target operating temperature. In this way, by changing the distribution ratio of the input gas flow rates of the cathode heater and heat exchanger, the cathode input gas temperature of the fuel cell stack can be changed, thereby changing the fuel cell stack operating temperature and keeping it within the preset temperature range.

[0126] Figure 8 This is a flowchart illustrating another battery thermal management method according to an exemplary embodiment, such as... Figure 8 As shown, step 103 can be achieved through the following steps:

[0127] Step 1031: When the cathode heater is an electric heater and the second flow distribution ratio is not the initial flow distribution ratio, adjust the heating power of the electric heater to adjust the temperature of the output gas of the cathode heater.

[0128] Step 1032: When the cathode heater is a burner and the second flow distribution ratio is not the initial flow distribution ratio, adjust the fuel input of the burner to adjust the temperature of the output gas of the cathode heater.

[0129] For example, after adjusting the input gas flow rates of the cathode heater and heat exchanger according to the second flow distribution ratio, the change in the flow distribution ratio will cause a change in the cold-side outlet temperature of the heat exchanger, resulting in the cathode input gas temperature of the fuel cell stack deviating from the preset temperature. Furthermore, the flow distribution ratio will not be the initial flow distribution ratio, affecting the economic operation of the power generation system. Therefore, the output gas temperature of the cathode heater can be adjusted to restore the initial flow distribution ratio by changing the flow distribution ratio of the input gas to the cathode heater and the heat exchanger. If the cathode heater is an electric heater and the second flow distribution ratio is not the initial flow distribution ratio, the output gas temperature of the cathode heater can be adjusted by adjusting the heating power of the electric heater. If the cathode heater is a burner and the second flow distribution ratio is not the initial flow distribution ratio, the output gas temperature of the cathode heater can be adjusted by adjusting the fuel input of the burner.

[0130] In summary, this disclosure applies to a power generation system for solid oxide fuel cells, which includes a fuel cell stack, a cathode heater, and a heat exchanger. The method first controls the input gas flow rates of the cathode heater and heat exchanger according to a first flow distribution ratio based on the output voltage and current of the fuel cell stack when the external load on the stack changes. Then, based on the operating temperature of the fuel cell stack, it controls the input gas flow rates of the cathode heater and heat exchanger according to a second flow distribution ratio. Finally, it adjusts the output gas temperature of the cathode heater based on the second flow distribution ratio and the initial flow distribution ratio. This disclosure, by adjusting the input gas flow rates of the cathode heater and heat exchanger sequentially based on the output power and operating temperature of the fuel cell stack when the external load on the fuel cell stack changes, ensures that the temperature of the fuel cell stack remains within a suitable operating temperature range, thereby improving the power generation efficiency and safety performance of the solid oxide fuel cell.

[0131] Figure 9 This is a block diagram illustrating a thermal management device for a battery according to an exemplary embodiment, such as... Figure 9As shown, a power generation system for a solid oxide fuel cell is described. The system includes a fuel cell stack, a cathode heater, and a heat exchanger. The outlet of the cathode heater is connected to the cathode inlet of the fuel cell stack. The cold-side outlet of the heat exchanger is connected to the cathode input of the fuel cell stack, and the cathode outlet of the fuel cell stack is connected to the hot-side inlet of the heat exchanger. The device 200 includes:

[0132] The first control module 201 is used to control the input gas flow of the cathode heater and the heat exchanger according to the output voltage and output current of the fuel cell stack and a first flow distribution ratio when the external load of the fuel cell stack changes.

[0133] The second control module 202 is used to control the input gas flow rate of the cathode heater and the heat exchanger according to the operating temperature of the fuel cell stack and the second flow distribution ratio.

[0134] The adjustment module 203 is used to adjust the output gas temperature of the cathode heater according to the second flow distribution ratio and the initial flow distribution ratio.

[0135] Figure 10 This is a block diagram illustrating a thermal management device for a battery according to an exemplary embodiment, such as... Figure 10 As shown, the device 200 also includes:

[0136] The repeat execution module 204 is used to repeatedly execute the steps of controlling the input gas flow rate of the cathode heater and the heat exchanger according to the second flow distribution ratio based on the operating temperature of the fuel cell stack, and adjusting the output gas temperature of the cathode heater according to the second flow distribution ratio and the initial flow distribution ratio, until the operating temperature of the fuel cell stack is within the preset temperature range and the second flow distribution ratio is equal to the initial flow distribution ratio.

[0137] In one application scenario, the second control module 202 is also used for:

[0138] When the operating temperature of the fuel cell stack is not within the preset temperature range, the input gas flow rate of the cathode heater and heat exchanger is controlled according to the third flow distribution ratio based on the operating temperature of the fuel cell stack. The operating temperature of the fuel cell stack is the time average of the cathode inlet gas temperature and the cathode outlet gas temperature.

[0139] The adjustment module 203 is also used to adjust the temperature of the output gas of the cathode heater according to the third flow distribution ratio and the initial flow distribution ratio.

[0140] In another application scenario, the first control module 201 is used for:

[0141] The heat generation of the fuel cell is determined based on its output voltage and output current.

[0142] The first flow rate allocation ratio is determined based on the heat generated by the fuel cell stack.

[0143] The input gas flow rate of the cathode heater and heat exchanger is controlled according to the first flow distribution ratio.

[0144] In another application scenario, the first control module 201 is used for:

[0145] The heat to be adjusted in the fuel cell is determined based on the heat generated by the fuel cell, the first heat carried by the input gas of the fuel cell, the second heat carried by the output gas of the fuel cell, and the third heat radiated by the fuel cell.

[0146] Determine the first flow rate allocation ratio based on the heat to be adjusted.

[0147] In another application scenario, the second control module 202 is used for:

[0148] The operating temperature of the fuel cell stack is determined based on the cathode inlet gas temperature and the cathode outlet gas temperature.

[0149] The second flow distribution ratio is determined based on the operating temperature of the fuel cell stack.

[0150] The input gas flow rate of the cathode heater and heat exchanger is controlled according to the second flow distribution ratio.

[0151] In another application scenario, the second control module 202 is used for:

[0152] The time-averaged average of the first heat carried by the cathode input gas and the second heat carried by the cathode output gas of the fuel cell stack is used as the operating temperature of the fuel cell stack.

[0153] The second flow distribution ratio is determined based on the operating temperature of the fuel cell stack and the preset target operating temperature.

[0154] In another application scenario, adjustment module 203 is used for:

[0155] When the cathode heater is an electric heater and the second flow distribution ratio is not the initial flow distribution ratio, the heating power of the electric heater is adjusted to adjust the temperature of the output gas of the cathode heater.

[0156] When the cathode heater is a burner and the second flow distribution ratio is not the initial flow distribution ratio, the fuel input of the burner is adjusted to adjust the temperature of the output gas of the cathode heater.

[0157] In summary, this disclosure applies to a power generation system for solid oxide fuel cells, which includes a fuel cell stack, a cathode heater, and a heat exchanger. The method first controls the input gas flow rates of the cathode heater and heat exchanger according to a first flow distribution ratio based on the output voltage and current of the fuel cell stack when the external load on the stack changes. Then, based on the operating temperature of the fuel cell stack, it controls the input gas flow rates of the cathode heater and heat exchanger according to a second flow distribution ratio. Finally, it adjusts the output gas temperature of the cathode heater based on the second flow distribution ratio and the initial flow distribution ratio. This disclosure, by adjusting the input gas flow rates of the cathode heater and heat exchanger sequentially based on the output power and operating temperature of the fuel cell stack when the external load on the fuel cell stack changes, ensures that the temperature of the fuel cell stack remains within a suitable operating temperature range, thereby improving the power generation efficiency and safety performance of the solid oxide fuel cell.

[0158] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0159] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0160] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A thermal management method for a battery, characterized in that, A power generation system for a solid oxide fuel cell, the power generation system comprising: a fuel cell stack, a cathode heater, and a heat exchanger, wherein the outlet of the cathode heater is connected to the cathode inlet of the fuel cell stack, the cold-side outlet of the heat exchanger is connected to the cathode input terminal of the fuel cell stack, and the cathode outlet of the fuel cell stack is connected to the hot-side inlet of the heat exchanger; the method comprising: When the external load of the fuel cell changes, the input gas flow rate of the cathode heater and the heat exchanger is controlled according to the output voltage and output current of the fuel cell and in accordance with the first flow distribution ratio. The input gas flow rates of the cathode heater and heat exchanger are controlled according to the operating temperature of the fuel cell stack and the second flow distribution ratio. The output gas temperature of the cathode heater is adjusted according to the second flow distribution ratio and the initial flow distribution ratio; The step of controlling the input gas flow rate of the cathode heater and heat exchanger according to the output voltage and output current of the fuel cell stack and in accordance with the first flow distribution ratio includes: The heat generation of the fuel cell is determined based on the output voltage and output current of the fuel cell. The first flow distribution ratio is determined based on the heat generated by the fuel cell stack; The input gas flow rates of the cathode heater and the heat exchanger are controlled according to the first flow distribution ratio; The step of controlling the input gas flow rate of the cathode heater and heat exchanger according to the operating temperature of the fuel cell stack and the second flow distribution ratio includes: The operating temperature of the fuel cell stack is determined based on the cathode inlet gas temperature and the cathode outlet gas temperature. The second flow distribution ratio is determined based on the operating temperature of the fuel cell stack; The input gas flow rate of the cathode heater and heat exchanger is controlled according to the second flow distribution ratio.

2. The method according to claim 1, characterized in that, The method further includes: Repeat the steps of controlling the input gas flow rate of the cathode heater and heat exchanger according to the second flow distribution ratio based on the operating temperature of the fuel cell stack, until the output gas temperature of the cathode heater is adjusted according to the second flow distribution ratio and the initial flow distribution ratio, until the operating temperature of the fuel cell stack is within the preset temperature range and the second flow distribution ratio is equal to the initial flow distribution ratio.

3. The method according to claim 1, characterized in that, The method further includes: When the operating temperature of the fuel cell stack is not within the preset temperature range, the input gas flow rate of the cathode heater and the heat exchanger is controlled according to the operating temperature of the fuel cell stack and the third flow distribution ratio. The operating temperature of the fuel cell stack is the time average of the cathode inlet gas temperature and the cathode outlet gas temperature of the fuel cell stack. The temperature of the output gas from the cathode heater is adjusted according to the third flow distribution ratio and the initial flow distribution ratio.

4. The method according to claim 1, characterized in that, Determining the first flow rate allocation ratio based on the heat generated by the fuel cell stack includes: The heat to be adjusted of the fuel cell is determined based on the heat generated by the fuel cell, the first heat carried by the input gas of the fuel cell, the second heat carried by the output gas of the fuel cell, and the third heat radiated by the fuel cell. The first flow distribution ratio is determined based on the heat to be adjusted.

5. The method according to claim 1, characterized in that, Determining the second flow distribution ratio based on the operating temperature of the fuel cell stack includes: The time-averaged average of the first heat carried by the cathode input gas and the second heat carried by the cathode output gas of the fuel cell stack is taken as the operating temperature of the fuel cell stack. The second flow distribution ratio is determined based on the operating temperature of the fuel cell stack and the preset target operating temperature.

6. The method according to claim 3, characterized in that, The step of adjusting the temperature of the output gas of the cathode heater according to the second flow distribution ratio and the initial flow distribution ratio includes: When the cathode heater is an electric heater and the second flow distribution ratio is not the initial flow distribution ratio, the heating power of the electric heater is adjusted to adjust the temperature of the output gas of the cathode heater. When the cathode heater is a burner and the second flow distribution ratio is not the initial flow distribution ratio, the fuel input of the burner is adjusted to adjust the temperature of the output gas of the cathode heater.

7. A thermal management device for a battery, characterized in that, A power generation system for a solid oxide fuel cell, the power generation system comprising: a fuel cell stack, a cathode heater, and a heat exchanger, wherein the outlet of the cathode heater is connected to the cathode inlet of the fuel cell stack, the cold-side outlet of the heat exchanger is connected to the cathode input terminal of the fuel cell stack, and the cathode outlet of the fuel cell stack is connected to the hot-side inlet of the heat exchanger; the device includes: The first control module is used to control the input gas flow rate of the cathode heater and the heat exchanger according to the output voltage and output current of the fuel cell stack and a first flow distribution ratio when the external load of the fuel cell stack changes. The second control module is used to control the input gas flow rate of the cathode heater and the heat exchanger according to the operating temperature of the fuel cell stack and the second flow distribution ratio. An adjustment module is used to adjust the output gas temperature of the cathode heater according to the second flow distribution ratio and the initial flow distribution ratio; The first control module is used for: The heat generation of the fuel cell is determined based on the output voltage and output current of the fuel cell. The first flow distribution ratio is determined based on the heat generated by the fuel cell stack; The input gas flow rates of the cathode heater and the heat exchanger are controlled according to the first flow distribution ratio; The second control module is used for: The operating temperature of the fuel cell stack is determined based on the cathode inlet gas temperature and the cathode outlet gas temperature. The second flow distribution ratio is determined based on the operating temperature of the fuel cell stack; The input gas flow rate of the cathode heater and heat exchanger is controlled according to the second flow distribution ratio.

8. The apparatus according to claim 7, characterized in that, The device further includes: The repetitive execution module is used to repeatedly execute the steps of controlling the input gas flow rate of the cathode heater and the heat exchanger according to the second flow distribution ratio based on the operating temperature of the fuel cell stack, and adjusting the output gas temperature of the cathode heater according to the second flow distribution ratio and the initial flow distribution ratio, until the operating temperature of the fuel cell stack is within a preset temperature range and the second flow distribution ratio is equal to the initial flow distribution ratio.

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