Water-free shutdown control method and system for air thermal management fuel cell system

Abstract

The invention provides a water-free shutdown control method and system for an air thermal management fuel cell system, and relates to the technical field of fuel cell systems, and the method comprises the following steps: introducing fuel when the system runs normally, and maintaining the cycle rate to load current; the method comprises the following steps: reducing the quantity of fuel introduced into a system, correspondingly loading current, detecting open-circuit voltage, maintaining a reducing atmosphere on the side wall of the fuel, adjusting the flow of a fan or the opening degree of a valve, reducing the temperature of a galvanic pile entering an air side of the galvanic pile, discontinuously introducing the fuel according to the open-circuit voltage of the galvanic pile in a galvanic pile temperature reducing process, and maintaining the reducing atmosphere on the fuel side, when the temperature value is reduced to an allowable inlet temperature value, entering a fuel consumption purging shutdown stage; the method comprises the following steps: detecting open-circuit voltage, blowing consumed fuel until shutdown, converting a reducing atmosphere at a fuel side into an oxidizing atmosphere, when the open-circuit voltage tends to 0V, enabling a system to enter a rapid cooling shutdown stage, and adjusting inlet temperatures at an air side and a fuel gas side of a stack according to an allowable maximum cooling rate, so as to realize rapid cooling shutdown.

Description

Technical Field

[0001] This disclosure relates to the field of fuel cell system technology, and specifically to a waterless shutdown control method and system for an air thermal management fuel cell system. Background Technology

[0002] The statements in this section are merely background information relating to this disclosure and do not necessarily constitute prior art.

[0003] Air thermal management is a core component for the efficient operation of fuel cell systems. Its performance directly affects the lifespan, efficiency, and applicable scenarios of the battery, and it has broad application prospects, especially in the transportation and energy sectors.

[0004] Existing air-thermal-managed fuel cells have residual fuel gas on the combustion side at medium to high temperatures, which can only be purged using external inert gases such as water vapor or nitrogen, increasing system complexity and equipment cost. Furthermore, the shutdown process of existing air-thermal-managed fuel cells relies on water or inert gas systems. A waterless shutdown of the fuel cell can be achieved by adding operable components to the system. Summary of the Invention

[0005] To address the aforementioned issues, this disclosure proposes a waterless shutdown control method and system for an air thermal management fuel cell system. By converting the reducing atmosphere of the fuel circuit circulation to an oxidizing state without affecting the lifespan of the fuel cell stack, it avoids carbon buildup and deflagration, and enables stable system operation at a lower cost, thus achieving waterless shutdown.

[0006] According to some embodiments, the present disclosure adopts the following technical solutions: A method for controlling the waterless shutdown of an air thermal management fuel cell system includes: During system operation, fuel is supplied normally, and the cycle rate is maintained to apply load current. When the shutdown control is initiated, the amount of fuel supplied to the system is reduced and the load current is applied accordingly. The open-circuit voltage is detected, the reducing atmosphere on the fuel side is maintained, the blower flow rate or valve opening is adjusted, and the fuel stack temperature on the air side of the fuel stack is reduced. During the process of reducing the fuel stack temperature, fuel is supplied intermittently according to the open-circuit voltage of the fuel stack to maintain the reducing atmosphere on the fuel side. When the temperature drops to the allowable inlet temperature value, the fuel consumption purging shutdown stage is entered. The open-circuit voltage is detected, and the system is purged with fuel until shutdown. The reducing atmosphere on the fuel side is converted into an oxidizing atmosphere. When the open-circuit voltage approaches 0V, the system enters the rapid cooling shutdown stage. The inlet temperatures of the fuel cell stack air side and gas side are adjusted according to the maximum allowable cooling rate to achieve rapid cooling shutdown.

[0007] Furthermore, the fuel and air exchange heat within the fuel cell system, and the anode exhaust gas comes into direct contact with the air at the burner. During the cooling process of the fuel-side gas, leakage from components or contraction of the fuel-side gas transports the anode exhaust gas to the burner pipe to replenish oxygen, providing oxidant for the reducing atmosphere to consume the fuel.

[0008] According to some embodiments, the present disclosure adopts the following technical solutions: A waterless shutdown control system for an air thermal management fuel cell system includes an air electrode side and a fuel electrode side. The air electrode side includes a burner, multiple valves, an air preheater, an anode exhaust gas cooler, and a fan. The fuel electrode side includes a fuel tank, a reformer, and a circulation pump. On the air electrode side, air enters from the fan and is divided into multiple paths by valves. One path of air enters the air preheater, another path enters the reformer, and the third path enters the anode tail gas cooler. The air entering the reformer regulates the working temperature of the reformer, and the air entering the anode tail gas cooler regulates the temperature of the anode tail gas circulating at the inlet of the circulating pump. After the temperature is regulated by the air preheater, the air is mixed with the air that has passed through the reformer and then enters the fuel cell stack. On the fuel electrode side, the fuel is depressurized from the fuel tank and split into two paths. One path enters the burner to participate in combustion and release heat, while the other path mixes with the anode exhaust gas output from the circulating pump and enters the reformer. After reforming, the fuel enters the stack sustaining system to generate electricity.

[0009] Furthermore, multiple valves on the air electrode side are connected in parallel to divide the air delivered by the fan into multiple paths, which enter the reformer, air preheater, and anode exhaust gas cooler respectively.

[0010] Furthermore, in the fuel cell stack, the cathode exhaust gas generated on the air side enters the burner on the air electrode side and undergoes an oxidation-reduction reaction with the fuel or anode exhaust gas entering the air electrode side from the fuel side, releasing heat. The flue gas after the reaction transfers the heat to the air side to maintain the normal power generation operation of the air thermal management fuel cell system.

[0011] Furthermore, the air thermal management fuel cell system also includes a fuel valve, an igniter, an electronic load, and a DC power supply.

[0012] Furthermore, during shutdown, the atmosphere on the fuel side and the open-circuit voltage of the fuel cell stack change. At the set circulating pump speed, the reducing atmosphere on the fuel side is disrupted due to leaks in the fuel cell stack, anode exhaust gas cooler, and reformer components that allow cross-heat exchange between air and fuel.

[0013] According to some embodiments, the present disclosure adopts the following technical solutions: A computer program product includes a computer program that, when executed by a processor, implements the waterless shutdown control method for an air thermal management fuel cell system.

[0014] According to some embodiments, the present disclosure adopts the following technical solutions: A non-transitory computer-readable storage medium is provided for storing computer instructions, which, when executed by a processor, implement a method for controlling the waterless shutdown of an air thermal management fuel cell system.

[0015] According to some embodiments, the present disclosure adopts the following technical solutions: An electronic device includes a processor, a memory, and a computer program; wherein the processor is connected to the memory, the computer program is stored in the memory, and when the electronic device is running, the processor executes the computer program stored in the memory to enable the electronic device to perform a method for controlling the waterless shutdown of an air thermal management fuel cell system.

[0016] Compared with the prior art, the beneficial effects of this disclosure are as follows: This disclosure discloses a method for controlling waterless shutdown in an air thermal management fuel cell system. The fuel cell system contains components that allow for cross-heat exchange between fuel and air, and the anode exhaust gas can directly contact the air at the burner. During the cooling process of the fuel-side gas, leakage from components or contraction of the fuel-side gas transports the anode exhaust gas to the burner piping to replenish oxygen, providing an oxidant for the reducing atmosphere that consumes the fuel. The oxidant, present in the reformer, partial oxidation reformer, and catalyst within the fuel stack, provides a site for the fuel-consuming reaction. This disclosure achieves waterless shutdown without the need for purging equipment, avoiding carbon buildup and deflagration, and enabling stable system operation at a lower cost.

[0017] This disclosure discloses a waterless shutdown control method for an air thermal management fuel cell system. It can achieve waterless shutdown of the fuel cell without adding any components, by converting the reducing atmosphere of the fuel circuit circulation to an oxidizing state without affecting the life of the fuel stack. It achieves shutdown purging of the fuel circuit and finally reaches a near-air state stagnation at a low temperature. Attached Figure Description

[0018] The accompanying drawings, which form part of this disclosure, are used to provide a further understanding of this disclosure. The illustrative embodiments of this disclosure and their descriptions are used to explain this disclosure and do not constitute an undue limitation of this disclosure.

[0019] Figure 1 This is a flowchart of a waterless shutdown control method for an air thermal management fuel cell system according to an embodiment of the present disclosure; Figure 2 This is a diagram illustrating the architecture of a waterless shutdown control system for an air thermal management fuel cell system according to an embodiment of this disclosure. Detailed Implementation

[0020] The present disclosure will be further described below with reference to the accompanying drawings and embodiments.

[0021] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this disclosure. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0022] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this disclosure. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0023] Example 1 One embodiment of this disclosure provides a method for controlling the waterless shutdown of an air thermal management fuel cell system, including: Step 1: When the system is running, fuel is supplied normally, and the cycle rate is maintained to apply the load current; Step 2: When the shutdown control is started, reduce the amount of fuel supplied to the system and apply the corresponding load current, detect the open circuit voltage, maintain the reducing atmosphere on the fuel side, adjust the blower flow or valve opening, reduce the fuel stack temperature on the air side of the fuel stack, and during the process of reducing the fuel stack temperature, fuel is supplied intermittently according to the open circuit voltage of the fuel stack to maintain the reducing atmosphere on the fuel side. When the temperature drops to the allowable inlet temperature value, the fuel consumption purging shutdown stage is entered. Step 3: Detect the open circuit voltage, purge with fuel until shutdown, convert the reducing atmosphere on the fuel side to an oxidizing atmosphere, and when the open circuit voltage approaches 0V, the system enters the rapid cooling shutdown stage. Adjust the inlet temperature of the fuel cell stack air side and gas side according to the maximum allowable cooling rate to achieve rapid cooling shutdown.

[0024] As one embodiment, this disclosure provides a method for controlling the waterless shutdown of an air-thermal management fuel cell system. The invention relates to fuel cells using natural gas or other hydrocarbon fuels. It utilizes catalysts such as nickel, nickel oxide, platinum, and rhodium present in the fuel-side reformer and the fuel stack to gradually consume the reducing components in the fuel, converting them into carbon dioxide and water vapor. This achieves fuel-side purging of the fuel path, ultimately reaching a near-air state at low temperatures. Figure 1 As shown, the specific implementation process is as follows: Step 0: When the system is running, fuel is supplied normally, and the load current is maintained at the set circulation rate. Step 1: Reduce the amount of fuel supplied to the system and apply the corresponding load current, gradually reducing it to 0A; Step 2: Detect the open circuit voltage and maintain a reducing atmosphere around the fuel. The open circuit voltage is the Nernst voltage generated by different atmospheres in the fuel stack. The voltage should not be too high to prevent carbon buildup. Step 3: Reduce the temperature of the fuel cell stack entering the air side by adjusting the blower flow rate, valve 3 opening degree, or the amount of fuel entering the fuel tank to reduce the temperature of the fuel cell stack air side inlet. Step 4: During the process of temperature reduction of the fuel cell system and stack, fuel is introduced discontinuously according to the open circuit voltage of the stack to maintain a reducing atmosphere on the fuel side. When the temperature drops to the allowable inlet temperature value (A value) on the gas side of the stack, the fuel consumption purging shutdown stage is entered. Step 5: Detect the open circuit voltage, purge with fuel until shutdown, and convert the reducing atmosphere on the fuel side into an oxidizing atmosphere. The open circuit voltage is the Nernst voltage generated by the difference in oxygen concentration on both sides of the fuel cell stack. This process is achieved by controlling the opening of valve 3 to maintain the reformer with high catalytic performance and realize the rapid consumption of the reducing components on the fuel side. The oxygen element required for the reaction comes from component leakage and cooling from the anode exhaust gas to the burner pipeline.

[0025] Step 6: When the open circuit voltage approaches 0V, the system enters the rapid cooling and shutdown stage. According to the maximum allowable cooling rate, the inlet temperature of the fuel cell stack air side and gas side is adjusted by parameters such as valve 1, valve 2, valve 3, air flow rate and burner fuel supply to achieve rapid cooling and shutdown.

[0026] Example 2 One embodiment of this disclosure provides a waterless shutdown control system for an air thermal management fuel cell system, such as... Figure 2 As shown, it includes an air electrode side and a fuel electrode side. The air electrode side includes a burner, multiple valves, an air preheater, an anode exhaust gas cooler, and a fan. The fuel electrode side includes a fuel tank, a reformer, and a circulation pump. On the air electrode side, air enters from the fan and is divided into multiple paths by valves. One path of air enters the air preheater, another path enters the reformer, and the third path enters the anode tail gas cooler. The air entering the reformer regulates the working temperature of the reformer, and the air entering the anode tail gas cooler regulates the temperature of the anode tail gas circulating at the inlet of the circulating pump. After the temperature is regulated by the air preheater, the air is mixed with the air that has passed through the reformer and then enters the fuel cell stack. On the fuel electrode side, the fuel is depressurized from the fuel tank and split into two paths. One path enters the burner to participate in combustion and release heat, while the other path mixes with the anode exhaust gas output from the circulating pump and enters the reformer. After reforming, the fuel enters the stack sustaining system to generate electricity.

[0027] As one embodiment, multiple valves on the air electrode side are connected in parallel to divide the air delivered by the fan into multiple paths, which enter the reformer, air preheater and anode exhaust gas cooler respectively.

[0028] Furthermore, on the air electrode side, the air delivered by the fan is transmitted through three pipelines, and a valve is installed on each pipeline for control, namely valve 1, valve 2 and valve 3, and the three valves are set in parallel.

[0029] As one example, such as Figure 2 As shown, multiple valves on the air electrode side are connected in parallel, and the opening degree of each valve can be adjusted. The valves divide the air delivered by the fan into multiple paths, which enter the reformer, air preheater and anode exhaust gas cooler respectively.

[0030] Specifically, on the air electrode side, air is transported by a fan and passes through pipelines controlled by three valves. On the pipeline controlled by valve 1, the air passes through valve 1 and is then transported to the anode exhaust gas cooler. On the pipeline controlled by valve 2, the air passes through valve 2 and is then transported to the air preheater. On the pipeline controlled by valve 3, the air passes through valve 3 and enters the reformer. On the fuel electrode side, fuel is depressurized from the fuel tank and split into two paths. One path enters the burner to participate in combustion and release heat, while the other path mixes with the anode exhaust gas output from the circulating pump and enters the reformer.

[0031] The air entering the reformer on the air electrode side is used to regulate the operating temperature of the reformer, while the air entering the anode exhaust gas cooler is used to regulate the temperature of the anode exhaust gas circulating at the inlet of the fuel electrode side circulation pump. The main air, heated by the air preheater, mixes with the air output from the reformer on the fuel cell side before entering the fuel cell stack and then the stack sustaining system for power generation. The fuel cell stack is a gas-based fuel cell device.

[0032] As one embodiment, in the fuel cell stack, the cathode exhaust gas generated on the air side enters the burner on the air electrode side and undergoes an oxidation-reduction reaction with the fuel or anode exhaust gas entering the air electrode side from the fuel side, releasing heat. The flue gas after the reaction transfers the heat to the air side to maintain the normal power generation operation of the air thermal management fuel cell system.

[0033] As one embodiment, catalysts such as nickel, nickel oxide, platinum, and rhodium are present in the reformer on the fuel side. These catalysts are widely distributed in the reformer, partial oxidation reformer, and fuel cell stack. Utilizing the catalysts such as nickel, nickel oxide, platinum, and rhodium present in the reformer on the fuel side, the reducing components in the fuel are gradually consumed and converted into carbon dioxide and water vapor, achieving fuel purging of the fuel path during shutdown, and ultimately reaching a near-air state at low temperature.

[0034] Example 3 One embodiment of this disclosure provides a computer program product, including a computer program that, when executed by a processor, implements the aforementioned method for controlling the waterless shutdown of an air thermal management fuel cell system.

[0035] Example 4 One embodiment of this disclosure provides a non-transitory computer-readable storage medium for storing computer instructions. When these computer instructions are executed by a processor, they implement a method for controlling the waterless shutdown of an air thermal management fuel cell system.

[0036] Example 5 One embodiment of this disclosure provides an electronic device, including a processor, a memory, and a computer program; wherein the processor is connected to the memory, and the computer program is stored in the memory. When the electronic device is running, the processor executes the computer program stored in the memory to enable the electronic device to implement the waterless shutdown control method for an air thermal management fuel cell system.

[0037] This disclosure is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a machine for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0038] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0039] While the specific embodiments of this disclosure have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of this disclosure. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of this disclosure are still within the scope of protection of this disclosure.

Claims

1. A method for controlling the waterless shutdown of an air thermal management fuel cell system, characterized in that, include: During system operation, fuel is supplied normally, and the cycle rate is maintained to apply load current. When the shutdown control is initiated, the amount of fuel supplied to the system is reduced and the load current is applied accordingly. The open-circuit voltage is detected, the reducing atmosphere on the fuel side is maintained, the blower flow rate or valve opening is adjusted, and the fuel stack temperature on the air side of the fuel stack is reduced. During the process of reducing the fuel stack temperature, fuel is supplied intermittently according to the open-circuit voltage of the fuel stack to maintain the reducing atmosphere on the fuel side. When the temperature drops to the allowable inlet temperature value, the fuel consumption purging shutdown stage is entered. The open-circuit voltage is detected, and the system is purged with fuel until shutdown. The reducing atmosphere on the fuel side is converted into an oxidizing atmosphere. When the open-circuit voltage approaches 0V, the system enters the rapid cooling shutdown stage. The inlet temperatures of the fuel cell stack air side and gas side are adjusted according to the maximum allowable cooling rate to achieve rapid cooling shutdown.

2. The method for controlling the waterless shutdown of an air thermal management fuel cell system as described in claim 1, characterized in that, In a fuel cell system, fuel and air exchange heat, and the anode exhaust gas comes into direct contact with air at the burner. During the cooling process of the fuel-side gas, leakage from components or contraction of the fuel-side gas can transport the anode exhaust gas to the burner pipe to replenish oxygen and provide oxidant for the reducing atmosphere to consume fuel.

3. A waterless shutdown control system for an air thermal management fuel cell system, characterized in that, Specifically, the method for controlling the waterless shutdown of an air thermal management fuel cell system as described in any one of claims 1-2 includes an air electrode side and a fuel electrode side. The air electrode side includes a burner, multiple valves, an air preheater, an anode exhaust gas cooler, and a fan. The fuel electrode side includes a fuel tank, a reformer, and a circulation pump. On the air electrode side, air enters from the fan and is divided into multiple paths by valves. One path of air enters the air preheater, another path enters the reformer, and the third path enters the anode tail gas cooler. The air entering the reformer regulates the working temperature of the reformer, and the air entering the anode tail gas cooler regulates the temperature of the anode tail gas circulating at the inlet of the circulating pump. After the temperature is regulated by the air preheater, the air is mixed with the air that has passed through the reformer and then enters the fuel cell stack. On the fuel electrode side, the fuel is depressurized from the fuel tank and split into two paths. One path enters the burner to participate in combustion and release heat, while the other path mixes with the anode exhaust gas output from the circulating pump and enters the reformer. After reforming, the fuel enters the stack sustaining system to generate electricity.

4. The waterless shutdown control system for an air thermal management fuel cell system as described in claim 3, characterized in that, include: Multiple valves on the air electrode side are connected in parallel to divide the air delivered by the fan into multiple paths, which enter the reformer, air preheater and anode exhaust gas cooler respectively.

5. The waterless shutdown control system for an air thermal management fuel cell system as described in claim 3, characterized in that, include: In the fuel cell stack, the cathode exhaust gas generated on the air side enters the burner on the air electrode side and undergoes an oxidation-reduction reaction with the fuel or anode exhaust gas entering the air electrode side from the fuel side, releasing heat. The flue gas after the reaction transfers the heat to the air side to maintain the normal power generation operation of the air thermal management fuel cell system.

6. The waterless shutdown control system for an air thermal management fuel cell system as described in claim 3, characterized in that, include: The air thermal management fuel cell system also includes a fuel valve, an igniter, an electronic load, and a DC power supply.

7. The waterless shutdown control system for an air thermal management fuel cell system as described in claim 3, characterized in that, include: During shutdown, the atmosphere on the fuel side and the open-circuit voltage of the fuel cell stack change. At the set circulation pump speed, the reducing atmosphere on the fuel side is disrupted due to leaks in the fuel cell stack, anode exhaust gas cooler, and reformer components that allow cross-heat exchange between air and fuel.

8. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the waterless shutdown control method for an air thermal management fuel cell system as described in any one of claims 1-2.

9. A non-transitory computer-readable storage medium, characterized in that, The non-transitory computer-readable storage medium is used to store computer instructions, which, when executed by a processor, implement a waterless shutdown control method for an air thermal management fuel cell system as described in any one of claims 1-2.

10. An electronic device, characterized in that, include: The device includes a processor, a memory, and a computer program; wherein the processor is connected to the memory, the computer program is stored in the memory, and when the electronic device is running, the processor executes the computer program stored in the memory to enable the electronic device to perform a method for controlling the waterless shutdown of an air thermal management fuel cell system as described in any one of claims 1-2.

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