A method, apparatus, device and storage medium for thermal control of a fuel cell system

Abstract

The application discloses a kind of heat control method, device, equipment and storage medium of fuel cell system, wherein method includes: according to each operation scheduling instruction of power grid determines the corresponding heat standby demand of power grid;According to each heat standby demand determines corresponding emergency backup temperature, third quantity and fourth quantity;The temperature of emergency backup stack is maintained at emergency backup temperature, the third quantity of heat standby stack is kept as heat standby state, and the fourth quantity of heat standby stack is switched from heat standby state to working state;When the fourth quantity of heat standby stack fails after state switching, determine the fifth quantity of the heat standby stack that fails, cut off the fifth quantity of heat standby stack, switch the fifth quantity of emergency backup stack to working state, and maintain the remaining emergency backup stack at emergency backup temperature.The application can reduce power supply instability, ensure stable power supply of system, and be conducive to smooth operation and sustainable development of power system.

Description

Technical Field

[0001] This invention relates to the field of fuel cell technology, and in particular to a thermal control method, apparatus, device, and storage medium for a fuel cell system. Background Technology

[0002] In recent years, with the large-scale grid connection of renewable energy, the stability and security of the power grid have faced significant challenges. Due to the intermittency and volatility of renewable energy power generation, as well as its increasing penetration rate, there is a certain degree of impact on the normal operation and dispatch of the power grid. In order to utilize more renewable energy as much as possible and improve the reliability and efficiency of power grid operation, various energy storage technologies have been rapidly developed.

[0003] Energy storage technologies mainly include two types: batteries and supercapacitors. Among them, solid oxide fuel cells (SOFCs) are renewable energy conversion devices that can efficiently convert the chemical energy stored in fuel and oxidant into electrical energy directly at medium and high temperatures. SOFCs have an energy utilization rate of up to 80% to 90% and have advantages such as low carbon emissions, environmental friendliness, high efficiency, and easy availability, making them one of the energy device options with great potential.

[0004] SOFC (Solar-Fiber Combined Unit) battery stacks play a crucial role in power system regulation. When the real-time operating power of an SOFC stack needs to be increased according to grid dispatch instructions, the hot-standby stack should immediately commence operation as preset by the system. However, in practical applications, the hot-standby stack may exhibit very low operating efficiency, failing to reach a stable operating state in a timely manner, thus hindering its ability to respond promptly to external demands.

[0005] Therefore, the faulty SOFC stack should be dealt with immediately, and other SOFC stacks in hot standby should be switched to operating status. However, SOFC stacks require heat to maintain temperature during hot standby, thus, an efficient and safe thermal control method for fuel cell systems is urgently needed. Summary of the Invention

[0006] The purpose of this invention is to provide a thermal control method, apparatus, device, and storage medium for a fuel cell system, in order to solve the technical problem of the lack of an efficient and safe thermal control method for fuel cell systems in related technologies.

[0007] The objective of this invention can be achieved through the following technical solutions:

[0008] Option 1: A thermal control method for a fuel cell system, wherein the fuel cell system includes at least: a first number of standby fuel cell stacks and a second number of emergency backup fuel cell stacks, and the thermal control method for the fuel cell system includes:

[0009] The corresponding hot standby demand of the power grid is determined according to the various operation and dispatch instructions of the power grid;

[0010] Determine the corresponding emergency standby temperature, third quantity, and fourth quantity based on the aforementioned hot standby requirements;

[0011] Wherein, the emergency standby temperature is the temperature that the emergency standby fuel cell stack needs to maintain, the third quantity is the number of the hot standby fuel cell stacks that maintain a hot standby state, and the fourth quantity is the number of the hot standby fuel cell stacks that switch from the hot standby state to the working state.

[0012] The temperature of the emergency standby battery stack is maintained at the emergency standby temperature, the third number of hot standby battery stacks are kept in the hot standby state, and the fourth number of hot standby battery stacks are switched from the hot standby state to the working state.

[0013] When the fourth number of hot standby fuel cells fails after the state switch, the fifth number of hot standby fuel cells that failed is determined, the fifth number of hot standby fuel cells is disconnected, the fifth number of emergency backup fuel cells is switched to the working state, and the remaining emergency backup fuel cells are maintained at the emergency backup temperature.

[0014] Optionally, determining the corresponding hot standby demand of the power grid based on various operation and dispatch instructions of the power grid includes:

[0015] Based on the various operation and dispatch instructions of the power grid, the standby demand of the power grid is determined as the first standby demand and the second standby demand.

[0016] Optionally, determining the corresponding emergency standby temperature, third quantity, and fourth quantity based on each of the stated hot standby requirements includes:

[0017] When the hot standby demand of the power grid is the first hot standby demand, the number of hot standby fuel cells that need to be switched to cold shutdown state is determined according to the first hot standby demand as the sixth number;

[0018] The corresponding emergency standby temperature is determined as the first standby temperature based on the first hot standby requirement. The third quantity is the first quantity minus the sixth quantity, and the fourth quantity is zero.

[0019] Optionally, the first backup temperature is 150°C to 250°C.

[0020] Optionally, determining the corresponding emergency standby temperature, third quantity, and fourth quantity based on each of the stated hot standby requirements further includes:

[0021] When the standby demand of the power grid is the second standby demand, the corresponding emergency standby temperature is determined as the second standby temperature based on the second standby demand.

[0022] The third and fourth quantities are determined based on the second hot standby requirement, and the sum of the third and fourth quantities is equal to the first quantity.

[0023] Optionally, the second backup temperature is 450°C to 550°C.

[0024] Optionally, the second backup temperature is 650°C to 800°C.

[0025] Option 2: A thermal control device for a fuel cell system, wherein the fuel cell system includes at least: a first number of standby fuel cell stacks and a second number of emergency backup fuel cell stacks, and the thermal control device for the fuel cell system includes:

[0026] The demand determination module is used to determine the hot standby demand of the power grid based on the various operation and scheduling instructions of the power grid.

[0027] The data determination module is used to determine the corresponding emergency standby temperature, third quantity, and fourth quantity based on each of the stated hot standby requirements;

[0028] Wherein, the emergency standby temperature is the temperature that the emergency standby fuel cell stack needs to maintain, the third quantity is the number of the hot standby fuel cell stacks that maintain a hot standby state, and the fourth quantity is the number of the hot standby fuel cell stacks that switch from the hot standby state to the working state.

[0029] A state switching module is used to maintain the temperature of the emergency standby stack at the emergency standby temperature, keep the third number of hot standby stacks in the hot standby state, and switch the fourth number of hot standby stacks from the hot standby state to the working state.

[0030] The fault handling module is used to determine the fifth number of hot standby fuel cells that have failed when the fourth number of hot standby fuel cells fail after the state switch, disconnect the fifth number of hot standby fuel cells, switch the fifth number of emergency backup fuel cells to the working state, and maintain the remaining emergency backup fuel cells at the emergency backup temperature.

[0031] Option 3, an electronic device, comprising: a processor and a memory;

[0032] The memory stores a computer program, and the processor executes the computer program to implement the steps of the method described in Scheme 1.

[0033] Option 4: A computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the method described in Option 1.

[0034] Based on the above technical solution, the beneficial effects of this invention are:

[0035] This invention determines the corresponding standby demand based on the power grid's operation and dispatch instructions, and determines the standby temperature of the emergency standby stack, a third number of standby stacks to maintain a standby state, and a fourth number to switch to operational status based on the standby demand. The emergency standby stacks are maintained at the standby temperature, and the fourth number of standby stacks are switched from standby to operational status. When a standby stack in operational status malfunctions, the malfunctioning stack is disconnected, and the emergency standby stacks are immediately switched to operational status. This invention can respond to increases in load demand in a short time, cope with peak-valley load fluctuations in the power system and intermittent power supply from renewable energy sources, handle emergencies, power outages, or other unforeseen events, reduce power supply instability, ensure stable power supply, improve the overall efficiency of the power system, and contribute to the stable operation and sustainable development of the power system. Attached Figure Description

[0036] Figure 1 This is a schematic flowchart of an embodiment of the thermal control method for a fuel cell system of the present invention;

[0037] Figure 2 This is a schematic diagram of the structure of an embodiment of the thermal control device of the fuel cell system of the present invention. Detailed Implementation

[0038] This invention provides a thermal control method, apparatus, device, and storage medium for a fuel cell system, addressing the technical problem of a lack of efficient and safe thermal control methods for fuel cell systems in related technologies.

[0039] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0040] Unless otherwise defined, 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 invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0041] Energy storage technology refers to storing excess electrical energy in various ways and releasing the stored energy when needed. Energy storage technology helps smart grids achieve more precise scheduling and control of power loads, improving the stability and security of the power system. In response to short-term power shortages, energy storage can play a role in peak shaving and demand-side response. Energy storage technology largely solves the problems of randomness and volatility in renewable energy generation, enabling smooth output of renewable energy power and effectively regulating changes in grid voltage, frequency, and phase caused by renewable energy generation, thus facilitating the convenient and reliable integration of large-scale wind and solar power into the conventional grid.

[0042] Energy storage technologies mainly include two types: batteries and supercapacitors. Battery technology is a chemical energy storage technology that converts electrical energy into chemical energy for storage and releases it as electrical energy when needed. Battery technology has significant advantages in achieving long-cycle and high-capacity storage and is widely used in energy storage power stations or distributed energy storage systems.

[0043] SOFCs operate at temperatures between 600-800℃, making them more suitable for use in stationary power generation or combined heat and power systems compared to proton exchange membrane fuel cells. Currently, domestically produced SOFC products offer new solutions for distributed power generation and microgrids. Compared to other fuel cell technologies, SOFCs have lower material and operating costs, higher safety, and are also low-carbon and environmentally friendly, making them a valuable supplement to green energy sources such as photovoltaics and wind power.

[0044] SOFC (Solar Fiber Cell) stack systems play a crucial role in power system regulation. These stack systems can be integrated into power grids to address peak-valley load fluctuations and intermittent power supply from renewable energy sources. By providing flexibility, reliability, and efficiency, they contribute to the smooth operation and sustainable development of the power system.

[0045] SOFC (Solar-Fired Fuel Cell) stack systems can respond quickly to increased load demand by increasing the operation of the stacks, providing additional power. This helps balance peak loads on the grid and reduce power supply instability. In the power system, SOFC stack systems can serve as backup power sources to handle emergencies, power outages, or other unforeseen events. SOFC stack systems can be combined with renewable energy sources such as solar and wind power for energy storage and to smooth the volatility of renewable energy, ensuring stable power supply. Through combined heat and power (CHP), SOFC stack systems can also improve the overall efficiency of the power system by utilizing waste heat to heat water or provide heating.

[0046] Solid oxide fuel cells (SOFCs) typically operate in two states: dynamic operation and steady-state operation, encompassing two conventional operating conditions. Dynamic operation involves the stack undergoing rapid changes within its operating temperature range, such as variations in load and fuel flow, requiring a rapid response to maintain performance. Steady-state operation involves the stack operating continuously at stable operating temperatures and conditions, maintaining the stability of the electrochemical reactions. In practical applications, SOFC stacks also require states such as cold start (starting from a low temperature), hot start (restarting from a high temperature), cold shutdown (cooling down to shut down), and hot standby (waiting for restart in a hot state). These states are designed to adapt to changing demands and operating conditions, ensuring the reliability and flexibility of the stack.

[0047] Specifically, dynamic operation refers to the process by which an SOFC stack experiences transient conditions or rapid changes within its operating temperature range, such as load changes or fuel flow rate changes. The stack must respond quickly to these changing operating conditions to maintain stable battery performance. Steady-state operation refers to the continuous operation of an SOFC stack under stable operating temperature and conditions. In steady-state operation, the stack maintains a stable electrochemical reaction state, and the fuel supply and battery temperature remain at a certain level. This is the ideal state for long-term operation of the stack.

[0048] In practical applications, to adapt to flexible and ever-changing scenario requirements, SOFC stack systems need to handle frequent start-up and shutdown operations, dynamic fluctuations, and power adaptation. Therefore, in addition to the normal operating states, SOFC stacks involve different operating states during startup and shutdown, such as cold start, warm start, cold shutdown, and warm standby.

[0049] Cold start refers to the process of starting a fully shut-down or cryogenic SOFC (Solar-Fuel Cell) stack from room temperature or cryogenic conditions and bringing it to operating temperature. During a cold start, the stack must first be heated from room temperature or cryogenic conditions to operating temperature, which typically takes a considerable amount of time. After the stack temperature reaches a certain level, fuel begins to enter the stack, and the electrochemical reaction begins to generate electricity. During a cold start, the heating rate needs to be controlled to avoid thermal stress and thermal expansion problems.

[0050] Hot start refers to the process of restarting an SOFC (Solar Fiber Optic Fuel Cell) stack from a state that has already reached its operating temperature. During a hot start, the stack is already at its operating temperature, so the electrochemical reaction can begin immediately to generate electricity. This is usually faster than a cold start because it does not require heating up the stack.

[0051] Cold shutdown refers to the process of cooling an SOFC stack from its operating temperature to room temperature or a cryogenic state and shutting it down completely. During a cold shutdown, the stack needs to cool down, the electrochemical reaction stops, and the fuel supply stops. This process can be achieved by controlling the gas flow rate, etc.

[0052] Hot standby refers to the state in which an SOFC (Solar Fiber Optic Fuel Cell) stack is kept at its operating temperature but its power output is temporarily stopped, allowing for rapid restart when needed. In hot standby, the stack remains at its operating temperature, but power output is temporarily halted, typically by turning off the power supply switch. In this state, the stack remains warm and can be restarted within a short time. Generally, standby mode for a fuel cell stack refers to hot standby (keeping it at operating temperature).

[0053] The inventors discovered through long-term research that the low efficiency of the SOFC hot standby stack when switching from hot standby to operating state could be due to a system malfunction causing an incorrect operating state, or it could be due to inherent issues with the hot standby stack itself. Regardless of the cause, the failure of the SOFC hot standby stack to enter a stable operating state in a timely manner will adversely affect the operation of the SOFC system.

[0054] When a fault occurs in the SOFC system, the faulty SOFC stack should be dealt with immediately. If there are other SOFC stacks in a hot standby state, that is, if there are other SOFC hot standby stacks, they should be switched to the other SOFC hot standby stacks immediately to switch from the hot standby state to the working state.

[0055] Of course, there may be a shortage of SOFC hot standby stacks. Therefore, setting up an SOFC emergency backup stack can be considered. When an SOFC stack is in hot standby mode, its temperature is near its operating temperature and it has no power output, but it can quickly respond to power output. Therefore, the stack needs to consume heat to maintain its temperature during hot standby. Since SOFC emergency backup stacks are used relatively infrequently, it is uneconomical to keep them at a high temperature indefinitely.

[0056] The main points regarding the insulation requirements for working and hot standby fuel cells are as follows:

[0057] Determine the total amount of combustible gas in the exhaust gas at the anode outlet of the working fuel cell stack and the heat that can be released by complete combustion, while also considering the heat loss of the high-temperature flue gas after combustion through pipeline transmission.

[0058] When the total heat supplied by the combustion of the exhaust gas at the anode outlet of the working fuel cell stack exceeds the demand of the working fuel cell stack, it is determined whether the heat available from the combustion of the exhaust gas at the anode of the hot standby fuel cell stack and the excess heat produced by the working fuel cell stack can meet the heat preservation requirements of the hot standby fuel cell stack. If they can meet the requirements, the hot standby fuel cell stack can be kept warm without increasing the fuel flow rate.

[0059] When the required heat cannot be met, the amount of heat that needs to be supplemented is determined. This is achieved by increasing the amount of fuel in the tail gas, especially for reformed gas, such as methanol or methane. The insufficient heat is directly supplemented by the combustion of methanol or methane, which is a mixed combustion, rather than increasing the reducing gas (reformed hydrogen-rich gas) in the standby fuel cell stack. This method is more efficient.

[0060] When an SOFC stack is in hot standby mode, it needs to be maintained near its operating temperature. To prevent oxidation of the anode (hydrogen electrode), a reducing gas (hydrogen) or a protective gas (nitrogen) needs to be supplied to the hydrogen electrode during hot standby. The protective gas is typically nitrogen, which requires external purchase or the installation of appropriate equipment. Generally, a reducing gas for power generation, such as hydrogen or reformed hydrogen-rich gas, can be directly supplied.

[0061] When the SOFC working stack is in operation, the raw material gas (hydrogen or reformed hydrogen-rich gas) is normally input. The unreacted anode tail gas is fed into the tail burner for combustion, and the high-temperature flue gas after combustion enters the working stack for heat preservation.

[0062] While standby SOFC stacks require a certain amount of reducing gas to prevent anodic oxidation, the flow rate is typically much lower than that of normally operating SOFC stacks. This results in the anode exhaust gas from standby stacks not being able to completely maintain the stack temperature stability after combustion. Although increasing the amount of fuel (reducing gas) can increase heat generation, this increases the consumption of raw materials, especially reformed fuels.

[0063] Please see Figure 1 This invention provides an embodiment of a thermal control method for a fuel cell system, wherein the fuel cell system includes at least: a first number of standby fuel cell stacks and a second number of emergency backup fuel cell stacks, and the thermal control method for the fuel cell system includes:

[0064] S100: Determine the corresponding hot standby demand of the power grid according to the various operation and dispatch instructions of the power grid;

[0065] S200: Determine the corresponding emergency standby temperature, third quantity, and fourth quantity based on the aforementioned hot standby requirements;

[0066] Wherein, the emergency standby temperature is the temperature that the emergency standby fuel cell stack needs to maintain, the third quantity is the number of the hot standby fuel cell stacks that maintain a hot standby state, and the fourth quantity is the number of the hot standby fuel cell stacks that switch from the hot standby state to the working state.

[0067] S300: Maintain the temperature of the emergency standby stack at the emergency standby temperature, keep the third number of hot standby stacks in the hot standby state, and switch the fourth number of hot standby stacks from the hot standby state to the working state;

[0068] S400: When the fourth number of hot standby batteries fails after the state switch, determine the fifth number of hot standby batteries that failed, disconnect the fifth number of hot standby batteries, switch the fifth number of emergency backup batteries to the working state, and maintain the remaining emergency backup batteries at the emergency backup temperature.

[0069] This invention provides a thermal management solution for working fuel cells, hot standby fuel cells, and emergency backup fuel cells. It can meet the insulation requirements of working and hot standby fuel cells while also satisfying the thermal requirements of emergency backup fuel cells. Simultaneously, it can switch a corresponding number of hot standby fuel cells from hot standby to working status according to different grid dispatch requirements. When a hot standby fuel cell in working status fails, a corresponding number of emergency backup fuel cells are immediately switched to working status to meet the power system's hot standby requirements.

[0070] Proper forecasting and dispatching of power load can ensure the stability of the power grid. Based on load variations, a typical 24-hour day can be divided into several load periods, such as peak demand, neutral demand, and off-peak demand. Power dispatching, by rationally scheduling the activation and deactivation of generator units according to load changes in different time periods, can effectively reduce costs, improve power supply efficiency, and enhance grid security.

[0071] In one embodiment, determining the corresponding standby demand of the power grid based on various operation and dispatch instructions of the power grid includes:

[0072] Based on the various operation and dispatch instructions of the power grid, the standby demand of the power grid is determined as the first standby demand and the second standby demand.

[0073] Based on the power grid's operation and dispatch instructions, the corresponding standby demand of the power grid can be determined. When the power load is low, the corresponding standby demand is also low; when the power load is high, the corresponding standby demand is also high. Therefore, the standby demand of the power grid can typically include: periods of low standby demand (for off-peak electricity demand) and periods of high standby demand (for peak electricity demand).

[0074] Specifically, the first hot standby demand can be the stage when hot standby demand is relatively low, close to the trough stage of hot standby demand; the second hot standby demand can be the stage when hot standby demand is relatively high, which is the peak and off-peak stages of hot standby demand.

[0075] In one embodiment, determining the corresponding emergency standby temperature, third quantity, and fourth quantity based on each thermal standby requirement includes:

[0076] When the grid's hot standby demand is the first hot standby demand, the number of hot standby fuel cells that need to be switched to cold shutdown state is determined to be the sixth number based on the first hot standby demand.

[0077] The corresponding emergency standby temperature is determined based on the first hot standby requirement. The third quantity is the first quantity minus the sixth quantity, and the fourth quantity is zero.

[0078] Specifically, the first standby demand can be a period of low standby demand, close to the trough of standby demand. The emergency response level of the emergency backup fuel cell stack (such as an SOFC emergency backup fuel cell stack) can be set to a low level, and the corresponding emergency backup temperature can be determined as the first backup temperature (e.g., 150℃ to 250℃). Maintaining the temperature of the emergency backup fuel cell stack at the first backup temperature means that the emergency backup fuel cell stack does not need to be kept in a standby state; that is, the emergency backup fuel cell stack does not need to be maintained at a high operating temperature (e.g., 650℃ to 800℃).

[0079] At this point, the emergency standby fuel cell stack is essentially a heat exchanger that can reduce the number of hot standby fuel cell stacks (such as SOFC hot standby fuel cell stacks). The number of hot standby fuel cell stacks to be reduced is determined to be the sixth number. That is, the state of the sixth number of hot standby fuel cell stacks can be switched from hot standby state to cold shutdown state. The remaining hot standby fuel cell stacks are still in hot standby state. That is, the number of hot standby fuel cell stacks in hot standby state is the first number minus the sixth number.

[0080] For example, the first quantity is 5, the second quantity is 2, the fourth quantity is 0, and the sixth quantity is 3; that is, the fuel cell system includes at least 5 hot standby stacks and 2 emergency backup stacks. During periods of low hot standby demand, switching 3 hot standby stacks from hot standby to cold shutdown is equivalent to reducing the number of hot standby stacks by 3, leaving 2 hot standby stacks still in hot standby mode. A fourth quantity of 0 indicates that during periods of low hot standby demand, it is not necessary to switch the hot standby stacks to operational mode.

[0081] During periods of low hot standby demand, the existing working fuel cells remain operational, and the number of hot standby fuel cells decreases. These hot standby fuel cells do not switch to operational status; in other words, the number of working fuel cells in the system remains constant. Besides maintaining the temperature of the working and hot standby fuel cells, excess high-temperature combustion gas is introduced into the emergency standby fuel cell. The emergency standby fuel cell is equipped with cooling water heat exchange pipes. By increasing the flow rate of the cooling water, heat exchange occurs between the emergency standby fuel cell and the emergency standby fuel cell, maintaining it at a first standby temperature, such as 150°C to 250°C. In a preferred embodiment, the first standby temperature is 200°C.

[0082] Understandably, when the emergency standby fuel cell stack is at its first standby temperature, it also serves as a tool for temperature regulation of the working and hot standby fuel cells. When the working or hot standby fuel cell stack overheats, a common method is to mix cold air with the high-temperature flue gas entering the stack to lower the temperature of the insulating gas, thereby removing excess heat from the working or hot standby fuel cell stack and stabilizing its temperature.

[0083] When the temperature of the working fuel cell stack is significantly overheated and a relatively large amount of cold air is needed for temperature regulation, the insulation exhaust gas at the first standby temperature of the emergency standby fuel cell stack can also be used. At this time, the insulation exhaust gas is about 200°C. Compared with the room temperature of the cold air, it can avoid the sudden cooling of the high temperature flue gas entering the working fuel cell stack, which would cause local cold spots in the fuel cell stack. This is especially true when the cold air and the high temperature flue gas entering the working fuel cell stack are mixed at the fuel cell stack inlet.

[0084] When the temperature rise of the fuel cell stack is relatively small and the required amount of cold air is relatively small, the extremely small air flow rate often cannot be input due to the valve opening. In this case, the emergency backup fuel cell stack at 450℃ to 550℃ is a good temperature control method. For example, if the second backup temperature is 500℃, which is not much different from the normal operating temperature of the fuel cell stack, such as 700℃, then when fine-tuning the fuel cell stack temperature, the amount of insulation exhaust gas required from the emergency backup fuel cell stack will inevitably be more than that required for cold air, and the flow rate will be easier to control. By mixing an appropriate amount of insulation exhaust gas from the emergency backup fuel cell stack with the high-temperature flue gas entering the working fuel cell stack, the temperature of the working fuel cell stack can be slightly reduced.

[0085] During periods of low hot standby demand, the number of working fuel cells remains unchanged, the number of hot standby fuel cells in hot standby state decreases, the number of emergency standby fuel cells remains unchanged, and the temperature of all emergency standby fuel cells is maintained at the first standby temperature.

[0086] In one embodiment, determining the corresponding emergency standby temperature, third quantity, and fourth quantity based on each thermal standby requirement further includes:

[0087] When the grid's standby demand is the second standby demand, the corresponding emergency standby temperature is determined as the second standby temperature based on the second standby demand.

[0088] The third and fourth quantities are determined based on the second hot standby demand, and the sum of the third and fourth quantities equals the first quantity.

[0089] Specifically, the second standby demand can be a period of high standby demand, such as a period of low standby demand. At this time, the emergency response level of the emergency standby stack is relatively high, and the corresponding emergency standby temperature is determined as the second standby temperature (e.g., 450°C to 550°C). The emergency standby stack needs to be kept close to the standby state. By appropriately reducing the flow rate of cooling water, heat exchange is carried out with the emergency standby stack to maintain the emergency standby stack at the second standby temperature, such as 450°C to 550°C. In a preferred embodiment, the second standby temperature is 500°C.

[0090] Simultaneously, based on the second hot standby requirement, the corresponding third and fourth quantities are determined. The state of the fourth quantity of hot standby battery stacks is switched from hot standby state to working state, that is, the fourth quantity of hot standby battery stacks becomes working battery stacks, and the number of working battery stacks increases by the fourth quantity; the number of hot standby battery stacks that are still in hot standby state is reduced by the fourth quantity, and the number of hot standby battery stacks that are still in hot standby state is the third quantity (the first quantity minus the fourth quantity).

[0091] In another embodiment, the second hot standby demand can be the peak phase of hot standby demand, during which the emergency standby stack needs to be kept in hot standby state. The corresponding emergency standby temperature is determined as the second standby temperature (e.g., 650°C to 800°C). At this time, more hot standby stacks need to be switched to the working state, and the fourth number during the peak phase is larger than that during the off-peak phase.

[0092] During off-peak periods of hot standby demand, the number of hot standby fuel cells deployed decreases, the probability of hot standby fuel cell failure is low, and the probability of emergency backup fuel cells being activated is also low. Therefore, the temperature of emergency backup fuel cells can be maintained between 450°C and 550°C. During peak periods of hot standby demand, the number of hot standby fuel cells deployed is high, the probability of hot standby fuel cell failure is high, and the probability of emergency backup fuel cells being activated is also high. Therefore, the temperature of emergency backup fuel cells needs to be maintained between 650°C and 800°C.

[0093] In step S400, when the fourth number of hot standby batteries fails after the state switch, the fifth number of hot standby batteries that failed is determined, the fifth number of hot standby batteries is disconnected, the fifth number of emergency backup batteries is switched to the working state, and the remaining emergency backup batteries are maintained at the emergency backup temperature.

[0094] A malfunction may occur when or after a SOFC hot standby stack switches from hot standby to operating status. If a malfunction occurs during the switch or if abnormal efficiency is observed (e.g., significantly lower efficiency than a normally operating stack), the low efficiency could be due to a system malfunction causing an incorrect operating state, or it could be due to a problem with the stack itself preventing it from reaching steady-state operation in a timely manner. In such cases, the malfunctioning SOFC stack should be addressed immediately.

[0095] It should be noted that the hot standby battery that malfunctioned may be a newly put into operation hot standby battery, or it may be an existing hot standby battery (which was put into operation before the fourth batch of hot standby batteries).

[0096] In one embodiment, when the fourth number of hot standby battery stacks fails after a state switch, the number of hot standby battery stacks that have failed is determined to be the fifth number. After the failure occurs, the fifth number of hot standby battery stacks is immediately disconnected, and the corresponding number of emergency backup battery stacks are switched from the hot standby state to the working state.

[0097] Specifically, when switching the emergency standby fuel cell stack to the working state, the cooling water heat exchange of the emergency standby fuel cell stack is shut down, and the high-temperature flue gas from the tail gas is introduced into the emergency standby fuel cell stack to the maximum extent, so that the temperature of the emergency standby fuel cell stack is urgently and rapidly raised to the working temperature. Then, the emergency standby fuel cell stack is immediately switched to the working state, and the hot standby fuel cell stack with abnormal working efficiency is immediately disconnected.

[0098] It should be noted that maximizing the flow rate of high-temperature flue gas from the tail gas into the emergency standby fuel cell stack means introducing high-temperature flue gas within the upper limit of the temperature gradient of the emergency standby fuel cell stack. This means heating the emergency standby fuel cell stack to its operating temperature in the shortest possible time to quickly replace the hot standby fuel cell stack that has malfunctioned or whose operating efficiency is abnormal. This allows the emergency standby fuel cell stack to be switched into a working fuel cell stack in an emergency and put into the power system as an emergency power source to meet the hot standby requirements of the power grid.

[0099] It should be noted that in practical applications, the hot standby requirements can be different, and the corresponding emergency backup temperature settings, third quantity, and fourth quantity can also be different.

[0100] For example, peak electricity demand is typically measured in daily increments, but under extreme cold, heat, or other extreme weather conditions, peak electricity demand can be significantly higher than daily peaks. In such cases, to further leverage the important role of the SOFC system in grid regulation, peak electricity demand under extreme weather conditions can be categorized into a new level. In this situation, the probability of a fault occurring during the switching of the hot standby fuel cell stack to operational status or an abnormal efficiency of the hot standby fuel cell stack is higher. The number of emergency backup fuel cell stacks can be set to two or more. Since the grid's hot standby demand is at its highest level, the hot standby fuel cell stacks are immediately disconnected, and the emergency backup fuel cell stacks are immediately switched to operational status.

[0101] Understandably, during periods of high demand for hot standby, the emergency standby fuel cell stack primarily serves as a safety backup; during periods of low demand for hot standby, the emergency standby fuel cell stack mainly functions as a heat exchanger, used to regulate the temperature of the working fuel cell stack and the hot standby fuel cell stack.

[0102] The thermal control method for a fuel cell system provided in this invention determines the corresponding standby demand based on the grid's operation and scheduling instructions. Based on this demand, it determines the standby temperature of the emergency standby stack, a third number of standby stacks to maintain a standby state, and a fourth number to switch to an operating state. The emergency standby stacks are maintained at the standby temperature, and the fourth number of standby stacks are switched from a standby state to an operating state. When a standby stack switched to an operating state malfunctions, the malfunctioning standby stack is disconnected, and the emergency standby stack is immediately switched to an operating state. This invention can respond to increases in load demand in a short time, cope with peak-valley load fluctuations in the power system and intermittent power supply from renewable energy sources, handle emergencies, power outages, or other unforeseen events, reduce power supply instability, ensure stable power supply, improve the overall efficiency of the power system, and contribute to the stable operation and sustainable development of the power system.

[0103] Please see Figure 2 This invention provides an embodiment of a thermal control device for a fuel cell system, the fuel cell system comprising at least: a first number of hot standby fuel cell stacks and a second number of emergency backup fuel cell stacks, the thermal control device for the fuel cell system comprising:

[0104] Demand determination module 11 is used to determine the hot standby demand of the power grid according to the various operation and scheduling instructions of the power grid;

[0105] Data determination module 22 is used to determine the corresponding emergency standby temperature, third quantity, and fourth quantity based on each of the stated hot standby requirements;

[0106] Wherein, the emergency standby temperature is the temperature that the emergency standby fuel cell stack needs to maintain, the third quantity is the number of the hot standby fuel cell stacks that maintain a hot standby state, and the fourth quantity is the number of the hot standby fuel cell stacks that switch from the hot standby state to the working state.

[0107] The state switching module 33 is used to maintain the temperature of the emergency standby stack at the emergency standby temperature, keep the third number of hot standby stacks in the hot standby state, and switch the fourth number of hot standby stacks from the hot standby state to the working state.

[0108] The fault handling module 44 is used to determine the fifth number of hot standby fuel cells that have failed when the fourth number of hot standby fuel cells fail after the state switch, disconnect the fifth number of hot standby fuel cells, switch the fifth number of emergency backup fuel cells to the working state, and maintain the remaining emergency backup fuel cells at the emergency backup temperature.

[0109] The thermal control device for a fuel cell system provided in this invention determines the corresponding standby demand based on the grid's operation and scheduling instructions. Based on this demand, it determines the standby temperature of the emergency standby stack, a third number of standby stacks to maintain a standby state, and a fourth number to switch to an operating state. The emergency standby stacks are maintained at the standby temperature, and the fourth number of standby stacks are switched from a standby state to an operating state. When a standby stack in the operating state malfunctions, the malfunctioning standby stack is disconnected, and the emergency standby stack is immediately switched to an operating state. This invention can respond to increases in load demand in a short time, cope with peak-valley load fluctuations in the power system and intermittent power supply from renewable energy sources, handle emergencies, power outages, or other unforeseen events, reduce power supply instability, ensure stable power supply, improve the overall efficiency of the power system, and contribute to the stable operation and sustainable development of the power system.

[0110] In addition, the present invention also provides an electronic device, including: a processor and a memory;

[0111] The memory stores a computer program, and the processor executes the computer program to implement the steps of the method described above.

[0112] In addition, the present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the method described.

[0113] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0114] In the embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, indirect coupling or communication connection between apparatuses or units, and may be electrical, mechanical, or other forms.

[0115] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0116] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0117] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0118] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A thermal control method for a fuel cell system, characterized in that, The fuel cell system includes at least: a first number of hot standby fuel cell stacks and a second number of emergency backup fuel cell stacks, and the thermal control method of the fuel cell system includes: The corresponding hot standby demand of the power grid is determined according to the various operation and dispatch instructions of the power grid; Determine the corresponding emergency standby temperature, third quantity, and fourth quantity based on the aforementioned hot standby requirements; Wherein, the emergency standby temperature is the temperature that the emergency standby fuel cell stack needs to maintain, the third quantity is the number of the hot standby fuel cell stacks that maintain a hot standby state, and the fourth quantity is the number of the hot standby fuel cell stacks that switch from the hot standby state to the working state. The temperature of the emergency standby battery stack is maintained at the emergency standby temperature, the third number of hot standby battery stacks are kept in the hot standby state, and the fourth number of hot standby battery stacks are switched from the hot standby state to the working state. When the fourth number of hot standby batteries fail after the state switch, the fifth number of hot standby batteries that failed is determined, the fifth number of hot standby batteries is disconnected, the fifth number of emergency backup batteries is switched to the working state, and the remaining emergency backup batteries are maintained at the emergency backup temperature. The step of determining the corresponding hot standby demand of the power grid according to the various operation and dispatch instructions of the power grid includes: According to the various operation and dispatch instructions of the power grid, the hot standby demand of the power grid is determined as the first hot standby demand and the second hot standby demand; The determination of the corresponding emergency standby temperature, third quantity, and fourth quantity based on each of the aforementioned hot standby requirements includes: When the hot standby demand of the power grid is the first hot standby demand, the number of hot standby fuel cells that need to be switched to cold shutdown state is determined according to the first hot standby demand as the sixth number; The corresponding emergency standby temperature is determined as the first standby temperature based on the first hot standby requirement. The third quantity is the first quantity minus the sixth quantity, and the fourth quantity is zero.

2. The thermal control method for a fuel cell system according to claim 1, characterized in that, The first backup temperature is 150°C to 250°C.

3. The thermal control method for a fuel cell system according to claim 1, characterized in that, The determination of the corresponding emergency standby temperature, third quantity, and fourth quantity based on each of the aforementioned hot standby requirements also includes: When the standby demand of the power grid is the second standby demand, the corresponding emergency standby temperature is determined as the second standby temperature based on the second standby demand. The third and fourth quantities are determined based on the second hot standby requirement, and the sum of the third and fourth quantities is equal to the first quantity.

4. The thermal control method for a fuel cell system according to claim 3, characterized in that, The second backup temperature is 450°C to 550°C.

5. The thermal control method for a fuel cell system according to claim 3, characterized in that, The second backup temperature is 650°C to 800°C.

6. A thermal control device for a fuel cell system, characterized in that, The fuel cell system includes at least: a first number of hot standby fuel cell stacks and a second number of emergency backup fuel cell stacks, and the thermal control device of the fuel cell system includes: The demand determination module is used to determine the hot standby demand of the power grid based on the various operation and scheduling instructions of the power grid. The data determination module is used to determine the corresponding emergency standby temperature, third quantity, and fourth quantity based on each of the stated hot standby requirements; Wherein, the emergency standby temperature is the temperature that the emergency standby fuel cell stack needs to maintain, the third quantity is the number of the hot standby fuel cell stacks that maintain a hot standby state, and the fourth quantity is the number of the hot standby fuel cell stacks that switch from the hot standby state to the working state. A state switching module is used to maintain the temperature of the emergency standby stack at the emergency standby temperature, keep the third number of hot standby stacks in the hot standby state, and switch the fourth number of hot standby stacks from the hot standby state to the working state. The fault handling module is used to determine the fifth number of hot standby fuel cells that have failed when the fourth number of hot standby fuel cells fail after the state switch, disconnect the fifth number of hot standby fuel cells, switch the fifth number of emergency backup fuel cells to the working state, and maintain the remaining emergency backup fuel cells at the emergency backup temperature when the fourth number of hot standby fuel cells fail. The step of determining the corresponding hot standby demand of the power grid according to the various operation and dispatch instructions of the power grid includes: According to the various operation and dispatch instructions of the power grid, the hot standby demand of the power grid is determined as the first hot standby demand and the second hot standby demand; The determination of the corresponding emergency standby temperature, third quantity, and fourth quantity based on each of the aforementioned hot standby requirements includes: When the hot standby demand of the power grid is the first hot standby demand, the number of hot standby fuel cells that need to be switched to cold shutdown state is determined according to the first hot standby demand as the sixth number; The corresponding emergency standby temperature is determined as the first standby temperature based on the first hot standby requirement. The third quantity is the first quantity minus the sixth quantity, and the fourth quantity is zero.

7. An electronic device, characterized in that, include: Processor and memory; The memory stores a computer program, and the processor executes the computer program to implement the steps of the method as described in any one of claims 1 to 5.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 5.

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