Fuel cell system and start-up control method for a fuel cell system

Abstract

The application discloses a fuel cell system and a starting control method applied to the fuel cell system. The first tail gas outlet of the first combustor is communicated with the inside of a high-temperature treatment module. A regenerator, a reformer and an anode input end of an electric pile are sequentially communicated. The gas output by the anode output end of the electric pile can be selectively delivered to a second heat exchange flow channel and / or the regenerator. The second heat exchange flow channel is communicated with a second combustor. A second tail gas outlet and a gas outlet are both communicated with a first heat exchange flow channel. The cathode output end of the electric pile is communicated with the second combustor. An air supply assembly can selectively supply air to an air flow channel and / or the first combustor. The air flow channel is also communicated with the cathode input end of the electric pile. A fuel supply assembly can selectively supply fuel to the first combustor and / or the regenerator. The efficiency of starting the electric pile can be improved, the electric pile can quickly enter a normal operation stage, and the problem that the electric pile still needs to rely on water during the normal operation process can be avoided.

Description

Technical Field

[0001] This invention relates to the field of fuel cell technology, and more particularly to fuel cell systems and start-up control methods applied to fuel cell systems. Background Technology

[0002] Clean energy is gaining increasing popularity. Among them, fuel cells, consisting of an anode, a cathode, and an electrolyte that allows ionic charges to flow between the anode and cathode, are chemical power generation devices that efficiently and environmentally convert the chemical energy stored in fuel into electrical energy directly at high temperatures. Therefore, they are widely believed to be widely used in the future.

[0003] Currently, although existing fuel cell systems have technologies for recycling anode exhaust gas to the reformer, they are inefficient during startup and still rely on water during normal operation of the stack. Summary of the Invention

[0004] The purpose of this invention is to provide a fuel cell system and a start-up control method for the fuel cell system, so as to solve the problems of low efficiency in the start-up process of the fuel cell system in the prior art and the need to rely on water during the normal operation of the fuel cell stack.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] A fuel cell system includes a stack, a gas supply and distribution module, an air heat exchanger, and a high-temperature treatment module. The gas supply and distribution module includes an air supply component, a fuel supply component, and a water supply component.

[0007] The high-temperature processing module includes a high-temperature resistant shell, and a first burner, a second burner, a regenerator, and a reformer disposed within the high-temperature resistant shell. The first exhaust gas outlet of the first burner is connected to the interior of the high-temperature resistant shell. The regenerator, the reformer, and the anode input terminal of the fuel cell stack are sequentially connected. The gas output from the anode output terminal of the fuel cell stack can be selectively delivered to the second heat exchange channel of the reformer and / or the regenerator. The second heat exchange channel is connected to the second burner. The second exhaust gas outlet of the second burner and the gas outlet of the high-temperature resistant shell are both connected to the first heat exchange channel of the air heat exchanger. The cathode output terminal of the fuel cell stack is connected to the second burner.

[0008] The air supply assembly can selectively supply air to the air passage of the air heat exchanger and / or the first burner, and the air passage is also connected to the cathode input terminal of the fuel cell stack.

[0009] The fuel supply assembly can selectively supply fuel to the first burner and / or the regenerator;

[0010] The water supply assembly can supply water to the regenerator.

[0011] As a preferred embodiment of the above-mentioned fuel cell system, the regenerator is further provided with a third heat exchange channel, and the anode output end of the fuel cell stack can be connected to the third heat exchange channel;

[0012] The high-temperature treatment module also includes an ejector disposed within the high-temperature resistant shell. The input port of the ejector is connected to the fuel supply assembly, the output port of the ejector is connected to the fuel input end of the regenerator, and the ejector inlet is connected to the third heat exchange channel.

[0013] As a preferred embodiment of the above-mentioned fuel cell system, along a first direction, the first burner is located at the first end of the high-temperature resistant shell, the second burner and the reformer are located at the second end of the high-temperature resistant shell, the regenerator is located between the reformer and the first burner, and the high-temperature resistant shell forms a gas flow channel with the second burner, the reformer, the first burner and the regenerator;

[0014] The first exhaust gas outlet of the first burner is connected to the gas flow channel;

[0015] The gas outlet is located at the second end of the high-temperature resistant shell and communicates with the gas flow channel. As a preferred embodiment of the above fuel cell system, the high-temperature processing module further includes a superheated steam coil, which is distributed within the high-temperature resistant shell and located at the first end of the high-temperature resistant shell along the first direction.

[0016] The superheated steam coil is connected to the water supply assembly and is also connected to the fuel input terminal of the regenerator.

[0017] As a preferred embodiment of the above-mentioned fuel cell system, a guide plate is provided inside the high-temperature resistant housing, which is used to guide the gas in the gas channel to the gas outlet.

[0018] A start-up control method for a fuel cell system, used to control the aforementioned fuel cell system, the start-up control method for the fuel cell system comprising:

[0019] Perform initial preheating: control the air supply assembly to supply air into the fuel cell stack and the first burner, control the fuel supply assembly to supply fuel into the first burner; ignite the first burner to perform initial preheating of the fuel cell stack and the high-temperature processing module;

[0020] Perform steam purging: Control the water supply component to supply water, heat the water supplied by the water supply component into steam and send it to the fuel cell stack to purge the fuel cell stack with steam; Control all the gas output from the anode output end of the fuel cell stack to be heat exchanged through the second heat exchange channel of the reformer and then delivered to the second burner.

[0021] Perform dual combustion to accelerate preheating: control the fuel supply assembly to also supply fuel to the regenerator; control all the gas output from the anode output terminal of the fuel cell stack to be delivered to the second burner for combustion or oxidation reaction;

[0022] Perform current-assisted preheating: Apply current to the fuel cell stack so that the fuel cell stack operates at minimum operating load;

[0023] Perform preheating switching: control the gas output from the anode output terminal of the fuel cell stack to be delivered to the second burner and the regenerator; gradually stop supplying fuel to the first burner and gradually stop supplying air to the first burner.

[0024] As a preferred embodiment of the above-mentioned start-up control method applied to a fuel cell system, after initial preheating of the fuel cell stack and the high-temperature processing module, the method further includes:

[0025] Determine whether the temperature of the gas output from the cathode output terminal of the fuel cell stack is greater than or equal to the set purging temperature; if the temperature of the gas output from the cathode output terminal of the fuel cell stack is greater than or equal to the set purging temperature, then steam purging can be performed.

[0026] As a preferred embodiment of the above-mentioned start-up control method applied to a fuel cell system, before controlling the water supply component to supply water during steam purging, the method further includes:

[0027] Water is supplied to the water supply assembly based on the expected purging duration and the set water volume required for the reformer to operate at the minimum oxygen-carbon ratio.

[0028] As a preferred embodiment of the above-mentioned start-up control method applied to a fuel cell system, during steam purging, after controlling all the gas output from the anode output terminal of the fuel cell stack to be heat-exchanged by the reformer and then delivered to the second burner, the method further includes:

[0029] Determine whether the temperature of the reformer is greater than or equal to the set minimum reforming reaction temperature; if the temperature of the reformer is greater than or equal to the set minimum reforming reaction temperature, then dual combustion accelerated preheating can be performed.

[0030] As a preferred embodiment of the above-mentioned start-up control method applied to fuel cell systems, when performing dual combustion accelerated preheating, the fuel supply component is controlled to supply fuel to the regenerator based on a water-to-carbon ratio greater than or equal to 2.

[0031] As a preferred embodiment of the above-mentioned start-up control method applied to a fuel cell system, during dual-combustion accelerated preheating, all the gas output from the anode output terminal of the fuel cell stack is controlled to be delivered to the second burner for combustion or oxidation reaction, and then the method further includes:

[0032] Determine whether the temperature at the cathode output terminal of the fuel cell stack is greater than or equal to the set minimum load temperature; if the temperature at the cathode output terminal of the fuel cell stack is greater than or equal to the set minimum load temperature, then current-assisted preheating can be performed.

[0033] As a preferred embodiment of the above-mentioned start-up control method applied to a fuel cell system, after the fuel cell stack operates at minimum working load during current-assisted preheating, the following further steps are included:

[0034] Whether preheating switching can be performed is determined based on the set switching temperature and the temperature of the cathode output terminal of the fuel cell stack; or, whether preheating switching can be performed is determined based on the air flow rate in the second burner.

[0035] As a preferred embodiment of the above-mentioned start-up control method applied to fuel cell systems, when performing current-assisted preheating, it further includes:

[0036] The temperature of the second burner is acquired in real time, and the air flow rate supplied to the fuel cell stack by the air supply component is controlled according to the temperature increase rate of the second burner.

[0037] As a preferred embodiment of the above-mentioned start-up control method applied to a fuel cell system, the specific steps of gradually stopping the supply of fuel to the first burner and gradually stopping the supply of air to the first burner include:

[0038] The amount of water supplied by the water supply component is reduced, thereby reducing the amount of steam supplied to the regenerator; after a first set time, the amount of air supplied by the air supply component to the first burner is halved, and the amount of fuel supplied by the fuel supply component to the first burner is halved; the flow rate of gas output from the anode output terminal of the fuel cell stack to the regenerator is gradually increased until the flow rate required for the fuel cell stack to operate at minimum operating load is reached; the water supply component is stopped supplying water to the regenerator; after a second set time, the air supply component is stopped supplying air to the first burner, and the fuel supply component is stopped supplying fuel to the first burner.

[0039] As a preferred embodiment of the above-mentioned start-up control method applied to fuel cell systems, the amount of water supplied by the water supply component is reduced according to y = [(O2:C)*xr*z] / (r+1);

[0040] Where y is the amount of water supplied by the water supply component; (O2:C) is the minimum oxygen-to-carbon ratio during the operation of the reformer; x is the fuel flow rate entering the regenerator; r is the exhaust gas recirculation rate, which is equal to the amount of fuel in the gas output from the anode output of the fuel cell stack that is ejected back to the fuel in the regenerator by the ejector / the total amount of gas output from the anode output of the fuel cell stack; and z is the oxygen flow rate entering the anode input of the fuel cell stack during load testing.

[0041] The beneficial effects of this invention are:

[0042] This invention provides a fuel cell system comprising a fuel cell stack, a gas supply and distribution module, an air heat exchanger, and a high-temperature treatment module. The gas supply and distribution module includes an air supply assembly, a fuel supply assembly, and a water supply assembly. The high-temperature treatment module includes a high-temperature resistant shell, and a first burner, a second burner, a regenerator, and a reformer disposed within the high-temperature resistant shell. The first exhaust gas outlet of the first burner is connected to the interior of the high-temperature resistant shell. The regenerator, the reformer, and the anode input terminal of the fuel cell stack are sequentially connected. The gas output from the anode output terminal of the fuel cell stack can be selectively delivered to... The reformer has a second heat exchange channel and / or a regenerator, the second heat exchange channel being connected to the second burner, and the second exhaust gas outlet of the second burner and the gas outlet of the high-temperature resistant shell being connected to the first heat exchange channel of the air heat exchanger; the cathode output end of the fuel cell stack is connected to the second burner; the air supply assembly can selectively supply air to the air channel of the air heat exchanger and / or the first burner, and the air channel is also connected to the cathode input end of the fuel cell stack; the fuel supply assembly can selectively supply fuel to the first burner and / or the regenerator; and the water supply assembly can supply water to the regenerator.

[0043] When the fuel cell system starts up, the air supply component supplies air to the stack and to the first burner, while the fuel supply component supplies fuel to the first burner. When the air and fuel flow rates in the first burner are sufficient for ignition, the first burner is ignited. The first exhaust gas outlet of the first burner is distributed within the high-temperature resistant shell, allowing the combustion exhaust gas to be discharged from the first exhaust gas outlet into the high-temperature resistant shell. This high-temperature combustion exhaust gas provides initial preheating to the regenerator, reformer, and second burner located within the high-temperature resistant shell. Simultaneously, the second exhaust gas outlet of the second burner and the gas outlet of the high-temperature resistant shell are both connected to the first heat exchange channel of the air heat exchanger, ensuring that the gas inside the high-temperature resistant shell... The gas ultimately flows through the gas outlet to the air channel of the air heat exchanger, heating the air supplied to the fuel cell stack by the air supply components via the air heat exchanger. Next, the air entering the fuel cell stack flows from the cathode output end to the second burner, and then from the second burner to the first heat exchange channel of the air heat exchanger, further heating the air supplied to the fuel cell stack by the air supply components via the air heat exchanger. Finally, the gas is discharged to the outside through the first heat exchange channel. During this process, the gas output from the anode output end of the fuel cell stack heats the second burner. Therefore, compared to existing technologies, this method can quickly and efficiently preheat the fuel cell stack, regenerator, reformer, and second burner, effectively improving the fuel cell stack startup efficiency and enabling the fuel cell stack to quickly enter the normal operation phase.

[0044] After the initial preheating is completed, the water supply assembly supplies water to the regenerator. Specifically, the water supplied by the water supply assembly is heated into steam by the high-temperature combustion exhaust gas from the first burner before being delivered to the regenerator. The steam then passes through the regenerator and reformer and enters the anode of the fuel cell stack, purging the stack and further preheating the stack, reformer, and regenerator. When the reformer temperature rises to a certain level, the fuel supply assembly supplies fuel to the regenerator, allowing the fuel and steam to undergo a reforming reaction in the reformer before flowing to the fuel cell stack. The gas output from the anode of the fuel cell stack is then entirely delivered to the second burner for combustion or oxidation. The heat generated by the combustion or oxidation reaction in the second burner further increases the temperature of the second burner, reformer, and regenerator, as well as the temperature of the fuel cell stack. When the temperature of the fuel cell stack further rises to a certain level... After setting a certain value, current is applied to the fuel cell stack to operate at minimum operating load, causing the stack temperature to rise further. When the stack temperature rises to a certain value, the gas output from the anode outlet is controlled to be transported to the second heat exchange channel and the regenerator. At this time, a portion of the anode tail gas begins to flow back to the fuel input of the regenerator and, after being reformed by the reformer, participates in the electrochemical reaction of the stack again, causing the stack temperature to rise further. Then, the supply of fuel to the first burner is gradually stopped, the supply of air to the first burner is gradually stopped, and the supply of steam to the regenerator is stopped based on the amount of steam flowing back to the combustion input of the regenerator from the anode tail gas. After the supply of steam to the regenerator is stopped, the raw materials for the electrochemical reaction of the stack are fuel, air, and the gas output from the anode outlet. Compared with the existing technology, this effectively avoids the problem that the stack still needs to rely on water during normal operation.

[0045] The present invention also provides a start-up control method for a fuel cell system. By controlling the fuel cell system using this start-up control method, the efficiency and effect of the fuel cell stack during startup can be effectively improved, enabling the fuel cell stack to quickly enter the normal operation stage. Moreover, compared with the prior art, it can effectively avoid the problem that the fuel cell stack still needs to rely on water during normal operation. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of a fuel cell system provided in a specific embodiment of the present invention;

[0047] Figure 2 This is a partial structural diagram of a fuel cell system provided in a specific embodiment of the present invention. Figure 1 ;

[0048] Figure 3 This is a partial structural diagram of a fuel cell system provided in a specific embodiment of the present invention. Figure 2 ;

[0049] Figure 4 This is a partial structural diagram of a fuel cell system provided in a specific embodiment of the present invention. Figure 3 ;

[0050] Figure 5 This is a partial structural diagram of a fuel cell system provided in a specific embodiment of the present invention. Figure 4 ;

[0051] Figure 6 This is a partial structural diagram of a fuel cell system provided in a specific embodiment of the present invention. Figure 5 ;

[0052] Figure 7 This is a flowchart of a startup control method for a fuel cell system provided in a specific embodiment of the present invention.

[0053] In the picture:

[0054] 1. Fuel cell stack;

[0055] 2. Gas supply and distribution module; 21. Air supply assembly; 22. Fuel supply assembly; 23. Water supply assembly; 24. First control valve; 25. Third control valve; 26. Fourth control valve;

[0056] 3. Air heat exchanger; 31. First heat exchange channel; 32. Air channel;

[0057] 4. High-temperature treatment module; 41. High-temperature resistant shell; 411. Gas flow channel; 412. Gas outlet; 42. First burner; 43. Second burner; 431. Second exhaust gas outlet; 44. Regenerator; 45. Reformer; 46. Ejector; 47. Superheated steam coil; 48. Baffle plate; 49. Second control valve;

[0058] 5. Heating box;

[0059] 6. Electrical modules;

[0060] 7. Basic power generation unit;

[0061] 81. Fuel pretreatment piping unit; 82. Water pretreatment piping unit; 83. Condensation box. Detailed Implementation

[0062] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0063] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0064] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0065] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0066] Currently, although existing fuel cell systems have technologies for recycling anode exhaust gas to the reformer, they are inefficient during startup and still rely on water during normal operation of the stack.

[0067] Therefore, as Figure 1-4As shown, the present invention provides a fuel cell system, which includes a fuel cell stack 1, a gas supply and distribution module 2, an air heat exchanger 3, and a high-temperature treatment module 4. The gas supply and distribution module 2 includes an air supply assembly 21, a fuel supply assembly 22, and a water supply assembly 23. The high-temperature treatment module 4 includes a high-temperature resistant housing 41, and a first burner 42, a second burner 43, a regenerator 44, and a reformer 45 disposed within the high-temperature resistant housing 41. The first exhaust gas outlet of the first burner 42 is connected to the interior of the high-temperature resistant housing 41. The regenerator 44, the reformer 45, and the anode input terminal of the fuel cell stack 1 are sequentially connected. The gas output from the anode output terminal of the fuel cell stack 1 can be selectively delivered to the reformer. The second heat exchange channel and / or regenerator 44 of the heat exchanger 45 are connected to the second burner 43. The second exhaust gas outlet 431 of the second burner 43 and the gas outlet 412 of the high-temperature resistant shell 41 are both connected to the first heat exchange channel 31 of the air heat exchanger 3. The cathode output end of the fuel cell stack 1 is connected to the second burner 43. The air supply assembly 21 can selectively supply air to the air channel 32 of the air heat exchanger 3 and / or the first burner 42. The air channel 32 is also connected to the cathode input end of the fuel cell stack 1. The fuel supply assembly 22 can selectively supply fuel to the first burner 42 and / or the regenerator 44. The water supply assembly 23 can supply water to the regenerator 44.

[0068] When the fuel cell system starts up, the air supply component 21 supplies air to the stack 1 and the first burner 42, while the fuel supply component 22 supplies fuel to the first burner 42. When the air and fuel flow rates in the first burner 42 are sufficient for ignition, the first burner 42 is ignited. By distributing the first exhaust gas outlet of the first burner 42 within the high-temperature resistant housing 41, the combustion exhaust gas of the first burner 42 is discharged into the high-temperature resistant housing 41 through the first exhaust gas outlet of the first burner 42. The high-temperature combustion exhaust gas preheats the regenerator 44, reformer 45, and second burner 43 located within the high-temperature resistant housing 41. Simultaneously, by connecting the second exhaust gas outlet 431 of the second burner 43 and the gas outlet 412 of the high-temperature resistant housing 41 to the first heat exchange channel 31 of the air heat exchanger 3, the high-temperature resistant housing... The gas inside 41 eventually flows through gas outlet 412 to air channel 32 of air heat exchanger 3, heating the air supplied by air supply component 21 to fuel cell stack 1 via air heat exchanger 3. Next, the air entering fuel cell stack 1 flows from cathode output end of fuel cell stack 1 to second burner 43, and then from second burner 43 to first heat exchange channel 31 of air heat exchanger 3, which also heats the air supplied by air supply component 21 to fuel cell stack 1 via air heat exchanger 3. Finally, the gas is discharged to the outside via first heat exchange channel 31. During this process, the gas output from cathode output end of fuel cell stack 1 can heat second burner 43. Therefore, compared with the prior art, it can quickly and efficiently preheat fuel cell stack 1, regenerator 44, reformer 45 and second burner 43, thereby effectively improving the start-up efficiency of fuel cell stack 1 and enabling fuel cell stack 1 to quickly enter the normal operation stage.

[0069] After the initial preheating is completed, the water supply component 23 supplies water to the regenerator 44. Specifically, the water supplied by the water supply component 23 is heated into steam by the high-temperature combustion exhaust gas emitted from the first burner 42 before being delivered to the regenerator 44. The steam passes through the regenerator 44 and the reformer 45 and then enters the fuel cell stack 1 to purge the fuel cell stack 1 with steam, thereby further preheating the fuel cell stack 1, the reformer 45, and the regenerator 44. When the temperature of the reformer 45 rises to a certain temperature... Then, the fuel supply assembly 22 supplies fuel to the regenerator 44, so that the fuel and water vapor undergo a reforming reaction in the reformer 45 and flow to the fuel cell stack 1. All the gas output from the anode of the fuel cell stack 1 is then sent to the second burner 43 for combustion or oxidation. The heat generated by the combustion or oxidation reaction in the second burner 43 further increases the temperature of the second burner 43, the reformer 45, and the regenerator 44, and the temperature of the fuel cell stack 1 also further increases. When the temperature of the fuel cell stack 1 reaches a certain level... After the temperature rises further to a certain value, current is applied to the fuel cell stack 1 to allow it to operate at minimum operating load, causing the temperature of the fuel cell stack 1 to rise further. When the temperature of the fuel cell stack 1 rises further to a certain value, the gas output from the anode output terminal of the fuel cell stack 1 is controlled to be transported to the second heat exchange channel and the regenerator 44. At this time, a portion of the anode tail gas begins to flow back to the fuel input terminal of the regenerator 44, and after being reformed by the reformer 45, it participates in the electrochemical reaction of the fuel cell stack 1 again, causing the temperature of the fuel cell stack 1 to rise further. Then, the supply of fuel to the first burner 42 is gradually stopped, the supply of air to the first burner 42 is gradually stopped, and the supply of water vapor to the regenerator 44 is stopped according to the amount of anode tail gas flowing back to the combustion input terminal of the regenerator 44. After the supply of water vapor to the regenerator 44 is stopped, the raw materials for the electrochemical reaction of the fuel cell stack 1 are fuel, air, and the gas output from the anode output terminal of the fuel cell stack 1. Compared with the prior art, this can effectively avoid the problem that the fuel cell stack 1 still needs to rely on water during normal operation.

[0070] Specifically, the combustion supplied by the fuel supply assembly 22 includes, but is not limited to, compressed natural gas, compressed propane, compressed butane, easily pressurized liquefied natural gas, methanol, ethanol, diesel, and city pipeline natural gas.

[0071] Specifically, such as Figure 1As shown, the gas supply module 2 also includes a first control valve 24. The input end of the first control valve 24 is connected to the output end of the air supply assembly 21. The first control valve 24 has multiple output ends, including at least a first output end connected to the air flow channel 32 of the air heat exchanger 3 and a second output end connected to the first burner 42. This configuration allows the air supply assembly 21 to selectively supply air to the air flow channel 32 of the air heat exchanger 3 and / or the first burner 42. Optionally, in this embodiment, the multiple output ends of the first control valve 24 also include a third output end connected to the high-temperature resistant housing 41. The third output end can purge toxic gases inside the high-temperature resistant housing 41 and can regulate the temperature of various components located inside the high-temperature resistant housing 41.

[0072] Among them, such as Figure 1 As shown, the regenerator 44 is also provided with a third heat exchange channel, which is connected to the anode output end of the fuel cell stack 1. The high-temperature treatment module 4 also includes an ejector 46 disposed in the high-temperature resistant shell 41. The inlet of the ejector 46 is connected to the fuel supply assembly 22, the outlet of the ejector 46 is connected to the fuel input end of the regenerator 44, and the ejection inlet of the ejector 46 is connected to the third heat exchange channel. This arrangement allows the gas output from the anode output end of the fuel cell stack 1 to enter the ejector 46 after heat exchange through the third heat exchange channel, and then be ejected back to the fuel input end of the regenerator 44 by the ejector 46 to participate in the electrochemical reaction of the fuel cell stack 1 again. As an alternative, the high-temperature treatment module 4 also includes a circulation pump and a circulation pipe. The inlet of the circulation pump is connected to the fuel supply assembly 22, the outlet of the circulation pump is connected to the fuel input end of the regenerator 44, and the circulation pipe connects the third heat exchange channel and the inlet of the circulation pump. This allows the gas output from the anode output end of the fuel cell stack 1 to be heat-exchanged through the third heat exchange channel and then flow to the circulation pipe, from the circulation pipe to the circulation pump, and then back to the fuel input end of the regenerator 44 to participate in the electrochemical reaction of the fuel cell stack 1 again.

[0073] Specifically, when the fuel supply assembly 22 supplies compressed natural gas, compressed propane, compressed butane, or easily pressurized liquefied natural gas, methanol, ethanol, diesel, etc., an ejector 46 is used. This allows the gas output from the anode output end of the fuel cell stack 1 to pass through the third heat exchange channel and enter the ejector 46, where it is ejected back to the fuel input end of the regenerator 44 to participate in the electrochemical reaction of the fuel cell stack 1 again. When the fuel supply assembly 22 supplies municipal pipeline natural gas, etc., a circulation pump is used to pressurize the gas. This allows the gas output from the anode output end of the fuel cell stack 1 to pass through the third heat exchange channel and flow to the circulation pipe, then to the circulation pump, and finally back to the fuel input end of the regenerator 44 to participate in the electrochemical reaction of the fuel cell stack 1 again.

[0074] Specifically, such as Figure 1 and Figure 3 As shown, the high-temperature processing module 4 also includes a second control valve 49. The input end of the second control valve 49 is connected to the anode output end of the fuel cell stack 1. The second control valve 49 has two output ends, one of which is connected to the second heat exchange channel and the other is connected to the third heat exchange channel. This allows the gas output from the anode output end of the fuel cell stack 1 to be selectively delivered to the second heat exchange channel of the reformer 45 and / or the third heat exchange channel of the regenerator 44.

[0075] Specifically, such as Figure 1 and Figure 3 As shown, the gas supply module 2 also includes a third control valve 25. The input end of the third control valve 25 is connected to the output end of the fuel supply assembly 22. The third control valve 25 has two output ends, one of which is connected to the first burner 42, and the other is connected to the input port of the ejector 46. This configuration allows the fuel supply assembly 22 to selectively supply fuel to the first burner 42 and / or the regenerator 44.

[0076] Preferably, such as Figure 3 As shown, along the first direction, the first burner 42 is located at the first end of the high-temperature resistant shell 41, the second burner 43 and the reformer 45 are located at the second end of the high-temperature resistant shell 41, and the regenerator 44 is located between the reformer 45 and the first burner 42. The high-temperature resistant shell 41, the second burner 43, the reformer 45, the first burner 42 and the regenerator 44 form a gas flow channel 411. The first exhaust gas outlet of the first burner 42 is connected to the gas flow channel 411. The gas outlet 412 is distributed at the second end of the high-temperature resistant shell 41 and is connected to the gas flow channel 411. The first exhaust gas outlet of the first burner 42 is connected to the gas flow channel 411, so that the high-temperature combustion exhaust gas discharged from the first exhaust gas outlet of the first burner 42 can directly heat the components such as the regenerator 44, reformer 45, and second burner 43 disposed in the high-temperature resistant shell 41 as it flows through the gas flow channel 411. Gas outlets 412 are distributed at the second end of the high-temperature resistant shell 41 and are connected to the gas flow channel 411, so that after heating the regenerator 44, reformer 45, and second burner 43, the combustion exhaust gas flows from the gas outlets 412 of the high-temperature resistant shell 41 to the first heat exchange channel 31 of the air heat exchanger 3, heating the air supplied to the fuel cell stack 1 by the air supply assembly 21 via the air heat exchanger 3. In this embodiment, as shown... Figure 3 As shown, an exemplary example is that two second burners 43 are provided at the second end of the high-temperature resistant housing 41. The second burners 43 include, but are not limited to, a diffusion burner and a catalytic oxidizer.

[0077] More preferably, such as Figure 3As shown, the high-temperature processing module 4 also includes a superheated steam coil 47, which is distributed within the high-temperature resistant shell 41 and located at the first end of the high-temperature resistant shell 41 along a first direction. The superheated steam coil 47 can be connected to the water supply component 23 and is also connected to the fuel input end of the regenerator 44. Specifically, the water supplied by the water supply component 23 first enters the superheated steam coil 47, is heated into steam within the superheated steam coil 47, and then flows from the superheated steam coil 47 to the regenerator 44. By setting the superheated steam coil 47 to be located at the first end of the high-temperature resistant shell 41 along a first direction, the efficiency of the high-temperature combustion exhaust gas discharged through the first burner 42 in heating the water in the superheated steam coil 47 into steam can be effectively improved, thereby further improving the start-up efficiency of the fuel cell stack 1 and the efficiency of the fuel cell stack 1 entering the normal operation stage.

[0078] Preferably, in this embodiment, such as Figure 3 As shown, the superheated steam coil 47 is disposed around the first exhaust gas outlet of the first burner 42. This further improves the efficiency of heating water in the superheated steam coil 47 into steam.

[0079] Specifically, in this embodiment, such as Figure 3 As shown, along the first direction, the ejector 46 is close to the first end of the high-temperature resistant shell 41 relative to the superheated steam coil 47. This arrangement makes the ejector 46 closer to the first burner 42, especially during the start-up phase, so as to heat the anode exhaust gas of the fuel cell stack 1 ejected by the ejector 46 and flowing back to the regenerator 44.

[0080] Specifically, such as Figure 1 and Figure 3 As shown, the gas supply and distribution module 2 also includes a fourth control valve 26. The input end of the fourth control valve 26 is connected to the output end of the water supply component 23, and the output end of the fourth control valve 26 is connected to the superheated steam coil 47.

[0081] Optionally, in this embodiment, as Figure 1 and Figure 3 As shown, the second control valve 49 is also located inside the high-temperature housing 41 and is positioned relative to the reformer 45 at the second end of the high-temperature housing 41 along the first direction.

[0082] Optionally, such as Figure 3As shown, a guide plate 48 is provided inside the high-temperature resistant shell 41. The guide plate 48 is used to guide the gas in the gas flow channel 411 to the gas outlet 412. This allows the gas in the gas flow channel 411 to flow smoothly to the gas outlet 412. Specifically, in this embodiment, four guide plates 48 are provided as an example. The four guide plates 48 are distributed in the gas flow channel 411, with two guide plates 48 distributed near the superheated steam coil 47, and the other two guide plates 48 distributed at intervals between the regenerator 44 and the second burner 43. It can be understood that the number of guide plates 48 can be increased or decreased according to the actual operating conditions, and the shape of the guide plates 48 can also be adjusted.

[0083] The fuel cell system also includes multiple temperature sensors, including at least a first temperature sensor, a second temperature sensor, a third temperature sensor, and a fourth temperature sensor. The first temperature sensor is used to monitor the temperature of the first burner 42, the second temperature sensor is used to monitor the temperature of the gas output from the cathode output terminal of the fuel cell stack 1, the third temperature sensor is used to monitor the temperature of the reformer 45, and the fourth temperature sensor is used to monitor the temperature of the second burner 43.

[0084] Optionally, the fuel cell stack 1, air heat exchanger 3, and high-temperature treatment module 4 are integrated into a single heat box 5; or, the fuel cell stack 1, air heat exchanger 3, and high-temperature treatment module 4 are each housed in a separate heat box 5. In this embodiment, as... Figure 5 As shown, taking the integration of fuel cell stack 1, air heat exchanger 3, and high-temperature processing module 4 into a single heat box 5 as an example, the integration level of the fuel cell system can be improved. It is understood that the arrangement of fuel cell stack 1, air heat exchanger 3, and high-temperature processing module 4 within the heat box 5 can be adapted to meet actual operating conditions.

[0085] Specifically, the gas outlet 412 of the high-temperature resistant shell 41 is connected to the first heat exchange channel 31 through the first tailpipe; the second exhaust gas outlet 431 of the second burner 43 is connected to the first heat exchange channel 31 through the second tailpipe.

[0086] Among them, such as Figure 6 As shown, the fuel cell stack 1, air heat exchanger 3, and high-temperature processing module 4 are all integrated into a heat box 5 to form the basic power generation unit 7. The fuel cell system also includes an electrical module 6, which, in this embodiment, is positioned above the basic power generation unit 7. It is understood that the relative positions of the electrical module 6 and the basic power generation unit 7 can be adaptively adjusted according to actual operating conditions.

[0087] Specifically, such as Figure 6As shown, there are multiple basic power generation units 7. The fuel cell system also includes a pretreatment pipeline unit and an integrated electrical unit. The pretreatment pipeline unit includes a fuel pretreatment pipeline unit 81 and a water pretreatment pipeline unit 82. The fuel pretreatment pipeline unit 81 connects the output of the fuel supply component 22 to the input of the third control valve 25 of each of the multiple basic power generation units 7. The water pretreatment pipeline unit 82 connects the output of the water supply component 23 to the input of the fourth control valve 26 of each of the multiple basic power generation units 7. This arrangement enables the simultaneous supply of fuel and water to multiple basic power generation units 7. Figure 6 As shown, multiple basic power generation units 7 are preferably arranged in a straight line.

[0088] More specifically, the water supply assembly 23 includes a water tank, and the water pretreatment pipeline unit 82 connects the output end of the water tank to the input end of the fourth control valve 26 of each of the multiple basic power generation units 7. This arrangement enables the simultaneous supply of water to the multiple basic power generation units 7 via the water tank.

[0089] Among them, such as Figure 6 As shown, the fuel cell system also includes a condenser 83, which is used to collect moisture from the gas flowing out of the first heat exchange channel 31 of each basic power generation unit 7. The water in the condenser 83 can be used to supply domestic heating, or as hot water for daily use, or as a water source for the water supply component 23, etc.

[0090] This invention also provides a start-up control method for a fuel cell system, used to control the aforementioned fuel cell system, such as... Figure 7 As shown, the start-up control method applied to a fuel cell system includes:

[0091] S100, Perform initial preheating. Specific steps include:

[0092] S110, control the air supply assembly 21 to supply air into the fuel cell stack 1 and the first burner 42, and control the fuel supply assembly 22 to supply fuel into the first burner 42.

[0093] S120, Ignite the first burner 42.

[0094] Specifically, the first burner 42 is ignited according to set fixed fuel flow and set fixed air flow values. More specifically, ignition is initiated when the fuel flow supplied to the first burner 42 is greater than or equal to the set fixed fuel flow and the air flow supplied to the first burner 42 is greater than or equal to the set fixed gas flow. It can be understood that when the fuel flow supplied to the first burner 42 is greater than or equal to the set fixed fuel flow and the air flow supplied to the first burner 42 is greater than or equal to the set fixed gas flow, it indicates that the fuel flow and air flow in the first burner 42 are sufficient for rapid and successful ignition. The set fixed fuel flow and air flow values ​​are empirical values ​​obtained from extensive prior testing.

[0095] Specifically, the ignition success of the first burner 42 is determined based on the set combustion temperature to ensure stable combustion and heat dissipation. More specifically, successful ignition is indicated when the temperature of the first burner 42 is greater than or equal to the set combustion temperature. The set combustion temperature is an empirical value obtained from extensive prior testing.

[0096] S130. Initial preheating of fuel cell stack 1 and high-temperature processing module 4.

[0097] Specifically, the first exhaust gas outlet of the first burner 42 is located within the high-temperature resistant shell 41, allowing the combustion exhaust gas from the first burner 42 to be discharged into the high-temperature resistant shell 41. The high-temperature combustion exhaust gas then preheats the regenerator 44, reformer 45, and second burner 43 located within the high-temperature resistant shell 41. Simultaneously, the second exhaust gas outlet 431 of the second burner 43 and the gas outlet 412 of the high-temperature resistant shell 41 are both connected to the first heat exchange channel 31 of the air heat exchanger 3. This allows the gas within the high-temperature resistant shell 41 to ultimately flow through the gas outlet 412 into the air channel 32 of the air heat exchanger 3, thus supplying the air to the air supply assembly 2. 1. The air supplied to the fuel cell stack 1 through the air heat exchanger 3 is heated. Then, the air entering the fuel cell stack 1 flows from the cathode output end of the fuel cell stack 1 to the second burner 43. After heat exchange in the second burner 43, the air enters the first heat exchange channel 31 of the air heat exchanger 3, which can also heat the air supplied to the fuel cell stack 1 through the air heat exchanger 3. Finally, the air is discharged to the outside through the first heat exchange channel 31. Therefore, compared with the prior art, the fuel cell stack 1, the regenerator 44, the reformer 45 and the second burner 43 can be preheated quickly and efficiently, thereby effectively improving the start-up efficiency of the fuel cell stack 1 and enabling the fuel cell stack 1 to quickly enter the normal operation stage.

[0098] S140. Determine whether to perform steam purging based on the temperature of the gas output from the cathode output terminal of fuel cell stack 1.

[0099] Specifically, the steps for determining whether to perform steam purging based on the temperature of the gas output from the cathode output terminal of fuel cell stack 1 include: determining whether the temperature of the gas output from the cathode output terminal of fuel cell stack 1 is greater than or equal to the set purging temperature; if the temperature of the gas output from the cathode output terminal of fuel cell stack 1 is greater than or equal to the set purging temperature, then steam purging can be performed. This setting ensures that when steam purging is performed, the steam entering the anode of fuel cell stack 1 does not condense inside fuel cell stack 1.

[0100] The purging temperature was set as an empirical value obtained from a large number of previous experiments.

[0101] S200, Perform steam purging. Specific steps include:

[0102] S210, Water is supplied to the water supply assembly 23 according to the expected purging time and the set water volume required for the reformer 45 to operate at the minimum oxygen-carbon ratio.

[0103] Specifically, the expected water volume required for purging can be calculated based on the steam flow rate and the estimated purging duration. Water is supplied to the water supply assembly 23 based on the sum of the expected water volume required for purging and the set water volume required for the reformer 45 to operate at the minimum oxygen-carbon ratio. It is understood that the water volume supplied to the water supply assembly 23 is greater than or equal to the sum of the expected water volume required for purging and the set water volume required for the reformer 45 to operate at the minimum oxygen-carbon ratio. The set water volume required for the reformer 45 to operate at the minimum oxygen-carbon ratio is an empirical value obtained from extensive prior testing.

[0104] Specifically, for a fuel cell system with one basic power generation unit 7, water is supplied to the water supply component 23 based on the sum of the expected water volume required for purging of a single stack 1 and the set water volume required for the reformer 45 to operate at the minimum oxygen-carbon ratio. For a fuel cell system with multiple basic power generation units 7, taking a fuel cell system with M basic power generation units 7 as an example, water is supplied to the water supply component 23 based on M*(the sum of the expected water volume required for purging of a single stack 1 and the set water volume required for the reformer 45 to operate at the minimum oxygen-carbon ratio), where M is a positive integer greater than 1.

[0105] S220, control the water supply component 23 to supply water, heat the water supplied by the water supply component 23 into water vapor and send it to the fuel cell stack 1 to purge the fuel cell stack 1 with water vapor.

[0106] Specifically, water is first supplied to the water tank of the water supply assembly 23 according to the number of basic power generation units 7; then, the fourth control valve 26 is controlled to connect the water tank and the superheated steam coil 47, and the water in the tank flows into the superheated steam coil 47; the superheated steam coil 47 approaches the first end of the high-temperature resistant shell 41 along the first direction, and the high-temperature combustion exhaust gas emitted by the first burner 42 heats the water in the superheated steam coil 47 into steam; the steam flows from the superheated steam coil 47 into the regenerator 44, then flows through the reformer 45 and enters the fuel cell stack 1 to purge the fuel cell stack 1 with steam. In this process, the regenerator 44, the reformer 45 and the fuel cell stack 1 can also be further heated.

[0107] S230, the gas output from the anode output terminal of the control stack 1 is all transported to the second burner 43 after heat exchange in the second heat exchange channel of the reformer 45.

[0108] Understandably, the steam purging of fuel cell stack 1 flows through the second heat exchange channel of reformer 45 into the second burner 43, then from the second burner 43 into the first heat exchange channel 31 of air heat exchanger 3, and finally exits from the first heat exchange channel 31. This arrangement also enables further preheating of fuel cell stack 1, regenerator 44, reformer 45, and second burner 43.

[0109] S240, determine whether to perform dual combustion accelerated preheating based on the temperature of reformer 45.

[0110] Specifically, the steps for determining whether to perform dual-combustion accelerated preheating based on the temperature of the reformer 45 include: determining whether the temperature of the reformer 45 is greater than or equal to the set minimum reforming reaction temperature; if the temperature of the reformer 45 is greater than or equal to the set minimum reforming reaction temperature, then dual-combustion accelerated preheating can be performed. This setting ensures that when dual-combustion accelerated preheating is performed, the water vapor and fuel entering the reformer 45 can effectively undergo a reforming reaction within the reformer 45.

[0111] The minimum reforming reaction temperature was set as an empirical value obtained from a large number of previous experiments.

[0112] Therefore, while achieving further preheating of the fuel cell stack 1, reformer 45, and regenerator 44 using steam, it also ensures that during dual-combustion accelerated preheating, the steam and fuel entering the reformer 45 can effectively undergo reforming reactions within the reformer 45. This further improves the efficiency and effectiveness of the fuel cell stack 1 startup.

[0113] S300, execute dual combustion accelerated preheating. Specific steps include:

[0114] In step S310, the fuel supply control assembly 22 also supplies fuel to the regenerator 44. This ensures that during the subsequent step S320, the combustion or oxidation reaction in the second burner 43 can further heat the second burner 43, the regenerator 44, the reformer 45, and the fuel cell stack 1.

[0115] Understandably, at this time, the control valve 25 connects the output end of the fuel supply assembly 22 with the input port of the first burner 42 and the ejector 46, so that the fuel supply assembly 22 simultaneously supplies fuel to the input port of the first burner 42 and the ejector 46. The fuel supplied to the ejector 46 flows from the output port of the ejector 46 to the regenerator 44, so as to supply fuel to the regenerator 44.

[0116] Preferably, the fuel supply assembly 22 supplies fuel to the regenerator 44 based on a water-to-carbon ratio greater than or equal to 2. Specifically, the amount of water vapor supplied to the regenerator 44 is calculated based on the fuel flow rate required for the fuel cell stack 1 to operate at its minimum operating load, ensuring that the water-to-carbon ratio is greater than or equal to 2. This configuration ensures that the fuel cell stack 1 can effectively carry out electrochemical reactions during subsequent current-assisted preheating, thus guaranteeing that the fuel cell stack 1 can operate at its minimum operating load. The minimum operating load of the fuel cell stack 1 is 5% to 10% of its rated load.

[0117] S320 controls the gas output from the anode output terminal of fuel cell stack 1 to be entirely supplied to the second burner 43 for combustion or oxidation reaction, thereby achieving auxiliary heating of the second burner 43.

[0118] Specifically, the high-temperature exhaust gas generated by the combustion or oxidation reaction in the second burner 43 is transported to the first heat exchange channel 31 through the second tailpipe. The combustion exhaust gas from the first burner 42, after heating the regenerator 44, reformer 45, and second burner 43 through the gas channel 411, is then transported to the first heat exchange channel 31 through the first tailpipe from the gas outlet 412 of the high-temperature resistant shell 41. This allows the combustion exhaust gas from the first burner 42 and the high-temperature exhaust gas from the second burner 43 to jointly heat the air supplied to the fuel cell stack 1 by the air supply assembly 21 via the air heat exchanger 3. This further increases the temperature of the fuel cell stack 1.

[0119] Secondly, the combined effect of the combustion exhaust gas from the first burner 42 and the heat radiation from the combustion or oxidation reaction in the second burner 43 can further heat components such as the regenerator 44 and the reformer 45 inside the high-temperature resistant shell 41.

[0120] Thus, the first burner 42 and the second burner 43 form a dual-combustion accelerated preheating effect, further improving the efficiency and effectiveness of the fuel cell stack 1 startup.

[0121] S330. Determine whether to perform current-assisted preheating based on the temperature of the cathode output terminal of fuel cell stack 1.

[0122] Specifically, the steps for determining whether to perform current-assisted preheating based on the temperature of the cathode output terminal of fuel cell stack 1 include: determining whether the temperature of the cathode output terminal of fuel cell stack 1 is greater than or equal to the set minimum load temperature; if the temperature of the cathode output terminal of fuel cell stack 1 is greater than or equal to the set minimum load temperature, then current-assisted preheating can be performed. This setting ensures that the temperature of fuel cell stack 1 is sufficient for operation under minimum working load.

[0123] The minimum load temperature was set as an empirical value obtained from a large number of previous tests.

[0124] S400, execute current-assisted preheating. Specific steps include:

[0125] S410. Apply current to fuel cell stack 1 so that it operates at minimum operating load. Due to the heat generated by the load on fuel cell stack 1, the temperature of fuel cell stack 1 will continue to rise.

[0126] However, since a portion of the calorific value of the fuel supplied to the anode input terminal of the fuel cell stack 1 is released as electrical energy, the calorific value of the anode exhaust gas and cathode exhaust gas that ultimately enter the second burner 43 will be reduced. Therefore, to address this phenomenon, the execution of step S400 also includes an air exit control method for the second burner 43, specifically including the following steps: real-time acquisition of the temperature of the second burner 43, and control of the air flow rate supplied to the fuel cell stack 1 by the air supply assembly 21 based on the temperature increase rate of the second burner 43.

[0127] Specifically, with the positive increase in the temperature growth rate of the second burner 43 as the control target, feedback control is performed on the air flow rate supplied by the air supply assembly 21 to the fuel cell stack 1, thereby controlling the air flow rate entering the second burner 43. More specifically, in this embodiment, the minimum temperature growth rate of the second burner 43 is set to a value between 3°C / min and 5°C / min.

[0128] This configuration ensures that the fuel cell stack 1, as well as components such as the second burner 43, reformer 45, and regenerator 44 located in the high-temperature resistant casing 41, continue to heat up, thereby further improving the efficiency and effectiveness of the fuel cell stack 1 during startup.

[0129] S420: Determine whether preheating switching can be performed based on the set switching temperature and the temperature of the cathode output terminal of fuel cell stack 1.

[0130] Specifically, the steps for determining whether preheating switching can be performed based on the set switching temperature and the temperature of the cathode output terminal of fuel cell stack 1 include: determining whether the temperature of the cathode output terminal of fuel cell stack 1 is greater than or equal to the set switching temperature; if the temperature of the cathode output terminal of fuel cell stack 1 is greater than or equal to the set switching temperature, then preheating switching can be performed. It can be understood that when the temperature of the cathode output terminal of fuel cell stack 1 is greater than or equal to the set switching temperature, it indicates that fuel cell stack 1 can operate orderly with minimum operating load, and the supply of steam to the regenerator 44 can be gradually stopped during the subsequent preheating switching stage, so that the raw materials for the electrochemical reaction of fuel cell stack 1 are converted into fuel, air, and the gas output from the anode output terminal of fuel cell stack 1. The set switching temperature is an empirical value obtained from a large number of previous experiments.

[0131] Among them, the setting scavenging temperature < the setting minimum reforming reaction temperature < the setting minimum load temperature < the setting switching temperature.

[0132] As an alternative, the ability to perform preheating switching can also be determined based on the air flow rate within the second burner 43. Specifically, when the air flow rate of the second burner 43 reaches the air flow rate required for the fuel cell stack 1 to operate at minimum operating load, it indicates that preheating switching can be performed.

[0133] S500, perform preheating switching, the specific steps include:

[0134] S510 controls the gas output from the anode output terminal of the fuel cell stack 1 to be delivered to the second burner 43 and the regenerator 44.

[0135] Specifically, the two output terminals of the second control valve 49 are connected to the second heat exchange channel and the third heat exchange channel respectively, so that the gas output from the anode output terminal of the fuel cell stack 1 is delivered to the second burner 43 and the regenerator 44.

[0136] Understandably, once it is determined that fuel cell stack 1 can operate in an orderly manner with minimum working load, the gas output from the anode output terminal of fuel cell stack 1 can be controlled to be delivered to the second burner 43 and the regenerator 44. At this time, a portion of the gas output from the anode output terminal of fuel cell stack 1, after heat exchange in the third heat exchange channel, is ejected by ejector 46 and flows back to the fuel input terminal of regenerator 44, thereby participating in the electrochemical reaction of fuel cell stack 1 and causing fuel cell stack 1 to continue to heat up.

[0137] S520, gradually stop supplying fuel to the first burner 42, and gradually stop supplying air to the first burner 42.

[0138] Specifically, the steps for gradually stopping the supply of fuel and air to the first burner 42 include:

[0139] The amount of water supplied by the water supply component 23 is reduced, thereby reducing the amount of steam supplied to the regenerator 44. After a first set time, the air supplied by the air supply component 21 to the first burner 42 is halved, and the fuel supplied by the fuel supply component 22 to the first burner 42 is halved. The flow rate of gas output from the anode output terminal of the fuel cell stack 1 to the regenerator 44 is gradually increased until the flow rate required for the fuel cell stack 1 to operate at minimum operating load is reached. The water supply component 23 is stopped supplying water to the regenerator 44. After a second set time, the air supply component 21 is stopped supplying air to the first burner 42, and the fuel supply component 22 is stopped supplying fuel to the first burner 42.

[0140] Understandably, after the first set time, the air supplied by the air supply component 21 to the first burner 42 is halved, and the fuel supplied by the fuel supply component 22 to the first burner 42 is halved, thus halving the power of the first burner 42 and weakening its heating effect on the fuel cell stack 1 and the various components inside the high-temperature housing 41. As the flow rate of the gas output from the anode output end of the fuel cell stack 1 to the regenerator 44 is gradually increased until the flow rate required for the fuel cell stack 1 to operate at minimum operating load is reached, the fuel cell stack 1 can use the fuel, air, and gas output from the anode output end of the fuel cell stack 1 as raw materials for the electrochemical reaction to operate in an orderly manner at minimum operating load, and the water supply component 23 can be controlled to stop supplying water. After the second set time, the electrochemical reaction of the fuel cell stack 1 stabilizes, and the air and fuel supplied to the first burner 42 are stopped. At this time, the preheating switch ends, and the fuel cell stack 1 enters the preheating stabilization stage.

[0141] Specifically, the amount of water supplied by the water supply component 23 is reduced according to y = [(O2:C)*xr*z] / (r+1); where y is the amount of water supplied by the water supply component 23; (O2:C) is the minimum oxygen-to-carbon ratio during the operation of the reformer 45; x is the fuel flow rate entering the regenerator 44; r is the exhaust gas recirculation rate, which is equal to the amount of gas output from the anode output terminal of the fuel cell stack 1 that is ejected back to the fuel input terminal of the regenerator 44 by the ejector 46 / the total amount of gas output from the anode output terminal of the fuel cell stack 1; and z is the oxygen flow rate entering the anode input terminal of the fuel cell stack 1 during load loading.

[0142] Specifically, in this embodiment, the range of the first set duration is 3 min to 5 min.

[0143] Specifically, in this embodiment, the range of the second set duration is 3 min to 5 min.

[0144] During the preheating and stabilization phase, once fuel stack 1 enters this phase, the temperature at the fuel output terminal of reformer 45 decreases because the first burner 42 has stopped operating. However, the flow rate of gas from the anode output terminal of fuel stack 1 returning to the fuel input terminal of regenerator 44 via the third heat exchange channel and ejector 46 has increased to the flow rate required for fuel stack 1 to operate at minimum operating load. This results in a high thermal inertia for regenerator 44, allowing the fuel output from regenerator 44 to enter reformer 45 and causing the temperature of reformer 45 to rise. When the temperature of fuel stack 1 stabilizes within the normal range for electrochemical reactions, the preheating and stabilization phase ends, and the start-up phase of fuel stack 1 concludes.

[0145] Specifically, after the start-up phase of fuel cell stack 1 is completed, it enters the normal operation phase. During the normal operation phase, fuel cell stack 1 operates normally using fuel, air, and the gas output from the anode terminal as raw materials for the electrochemical reaction. Compared with existing technologies, this effectively avoids the problem that fuel cell stack 1 still needs to rely on water during normal operation. Specifically, after the water supply to the regenerator 44 is stopped in step S520, fuel cell stack 1 no longer relies on water until it enters the normal operation phase, and during the operation of fuel cell stack 1 in the normal operation phase.

[0146] Therefore, by controlling the fuel cell system using the startup control method applied to the fuel cell system, the startup efficiency and effect of the fuel cell stack 1 can be effectively improved, enabling the fuel cell stack 1 to quickly enter the normal operation stage. Moreover, compared with the prior art, it can effectively avoid the problem that the fuel cell stack 1 still needs to rely on water during normal operation.

[0147] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A start-up control method for a fuel cell system, the fuel cell system comprising a stack (1), a gas supply and distribution module (2), an air heat exchanger (3), and a high-temperature treatment module (4), wherein the gas supply and distribution module (2) comprises an air supply component (21), a fuel supply component (22), and a water supply component (23), characterized in that: The high-temperature processing module (4) includes a high-temperature resistant shell (41), and a first burner (42), a second burner (43), a regenerator (44), and a reformer (45) disposed within the high-temperature resistant shell (41). The first exhaust gas outlet of the first burner (42) is connected to the interior of the high-temperature processing module (4). The regenerator (44), the reformer (45), and the anode input of the fuel cell stack (1) are connected in sequence. The gas output from the anode output of the fuel cell stack (1) can be selectively delivered to the second heat exchange channel of the reformer (45) and the regenerator (44). The second heat exchange channel is connected to the second burner (43). The second exhaust gas outlet (431) of the second burner (43) and the gas outlet (412) of the high-temperature resistant shell (41) are both connected to the first heat exchange channel (31) of the air heat exchanger (3). The cathode output of the fuel cell stack (1) is connected to the second burner (43). The air supply assembly (21) can selectively supply air to the air passage (32) of the air heat exchanger (3) and the first burner (42), and the air passage (32) is also connected to the cathode input terminal of the fuel cell stack (1). The fuel supply assembly (22) can selectively supply fuel to the first burner (42) and the regenerator (44); The water supply assembly (23) can supply water to the regenerator (44); The startup control method applied to the fuel cell system is used to control the fuel cell system, and the startup control method applied to the fuel cell system includes: Perform initial preheating: Control the air supply assembly (21) to supply air into the fuel cell stack (1) and the first burner (42), and control the fuel supply assembly (22) to supply fuel into the first burner (42); ignite the first burner (42) to perform initial preheating of the fuel cell stack (1) and the high-temperature processing module (4); Perform steam purging: Control the water supply component (23) to supply water, heat the water supplied by the water supply component (23) into steam and send it to the fuel cell stack (1) to perform steam purging on the fuel cell stack (1); Control all the gas output from the anode output end of the fuel cell stack (1) to be heat exchanged through the second heat exchange channel of the reformer (45) and then sent to the second burner (43); Perform dual combustion accelerated preheating: control the fuel supply assembly (22) to also supply fuel to the regenerator (44); control all the gas output from the anode output end of the fuel cell stack (1) to be delivered to the second burner (43) for combustion or oxidation reaction; Perform current-assisted preheating: apply current to the fuel cell stack (1) so that the fuel cell stack (1) operates at minimum working load; Perform preheating switching: control the gas output from the anode output terminal of the fuel cell stack (1) to be delivered to the second burner (43) and the regenerator (44); gradually stop supplying fuel to the first burner (42) and gradually stop supplying air to the first burner (42).

2. The start-up control method for a fuel cell system according to claim 1, characterized in that, The regenerator (44) is also provided with a third heat exchange channel, and the anode output end of the fuel cell stack (1) can be connected to the third heat exchange channel; The high-temperature processing module (4) further includes an ejector (46) disposed in the high-temperature resistant shell (41). The inlet of the ejector (46) can be connected to the fuel supply assembly (22), the outlet of the ejector (46) is connected to the fuel input end of the regenerator (44), and the ejection inlet of the ejector (46) is connected to the third heat exchange channel.

3. The start-up control method for a fuel cell system according to any one of claims 1-2, characterized in that, Along the first direction, the first burner (42) is located at the first end of the high-temperature resistant shell (41), the second burner (43) and the reformer (45) are located at the second end of the high-temperature resistant shell (41), the regenerator (44) is located between the reformer (45) and the first burner (42), and the high-temperature resistant shell (41) forms a gas flow channel (411) with the second burner (43), the reformer (45), the first burner (42) and the regenerator (44); The first exhaust gas outlet of the first burner (42) is connected to the gas flow channel (411); The gas outlet (412) is located at the second end of the high-temperature resistant shell (41) and is connected to the gas flow channel (411).

4. The start-up control method for a fuel cell system according to claim 3, characterized in that, The high-temperature processing module (4) further includes a superheated steam coil (47), which is distributed inside the high-temperature resistant shell (41) and located at the first end of the high-temperature resistant shell (41) along the first direction; The superheated steam coil (47) is connected to the water supply assembly (23), and the superheated steam coil (47) is connected to the fuel input end of the regenerator (44).

5. The start-up control method for a fuel cell system according to claim 3, characterized in that, The high-temperature resistant housing (41) is provided with a guide plate (48), which is used to guide the gas in the gas channel (411) to the gas outlet (412).

6. The start-up control method for a fuel cell system according to claim 1, characterized in that, During initial preheating, after initial preheating of the fuel cell stack (1) and the high-temperature processing module (4), the process further includes: Determine whether the temperature of the gas output from the cathode output terminal of the fuel cell stack (1) is greater than or equal to the set purging temperature; if the temperature of the gas output from the cathode output terminal of the fuel cell stack (1) is greater than or equal to the set purging temperature, then steam purging can be performed.

7. The start-up control method for a fuel cell system according to claim 1, characterized in that, Before controlling the water supply assembly (23) to supply water during steam purging, the following steps are also included: Water is supplied to the water supply assembly (23) according to the expected purging time and the set amount of water required for the reformer (45) to operate at the minimum oxygen-carbon ratio.

8. The start-up control method for a fuel cell system according to claim 1, characterized in that, During steam purging, the gas output from the anode of the fuel cell stack (1) is controlled to pass through the reformer (45) for heat exchange before being delivered to the second burner (43). The process also includes: Determine whether the temperature of the reformer (45) is greater than or equal to the set minimum reforming reaction temperature; if the temperature of the reformer (45) is greater than or equal to the set minimum reforming reaction temperature, then dual combustion accelerated preheating can be performed.

9. The start-up control method for a fuel cell system according to claim 1, characterized in that, When performing dual combustion accelerated preheating, the fuel supply component (22) is controlled to supply fuel to the regenerator (44) based on a water-to-carbon ratio greater than or equal to 2.

10. The start-up control method for a fuel cell system according to claim 1, characterized in that, During dual-combustion accelerated preheating, all the gas output from the anode output terminal of the fuel cell stack (1) is supplied to the second burner (43) for combustion or oxidation reaction, and then the process further includes: Determine whether the temperature of the cathode output terminal of the fuel cell stack (1) is greater than or equal to the set minimum load temperature; if the temperature of the cathode output terminal of the fuel cell stack (1) is greater than or equal to the set minimum load temperature, then current-assisted preheating can be performed.

11. The start-up control method for a fuel cell system according to claim 1, characterized in that, When performing current-assisted preheating, the fuel cell stack (1) further includes the following after operating at minimum working load: Whether preheating switching can be performed is determined based on the set switching temperature and the temperature of the cathode output terminal of the fuel cell stack (1); or, whether preheating switching can be performed is determined based on the air flow rate in the second burner (43).

12. The start-up control method for a fuel cell system according to claim 1, characterized in that, When performing current-assisted preheating, it also includes: The temperature of the second burner (43) is acquired in real time, and the air flow rate supplied by the air supply component (21) to the fuel cell stack (1) is controlled according to the temperature increase rate of the second burner (43).

13. The start-up control method for a fuel cell system according to claim 1, characterized in that, The specific steps for gradually stopping the supply of fuel and air to the first burner (42) include: Control the reduction of water supply from the water supply component (23) to reduce the amount of steam supplied to the regenerator (44); after a first set time, control the air supply component (21) to halve the air supplied to the first burner (42), and control the fuel supply component (22) to halve the fuel supplied to the first burner (42); control the gradual increase of the flow rate of gas output from the anode output end of the fuel cell stack (1) to the regenerator (44) until the flow rate required for the fuel cell stack (1) to operate at minimum working load is reached; control the water supply component (23) to stop supplying water to the regenerator (44); after a second set time, control the air supply component (21) to stop supplying air to the first burner (42), and control the fuel supply component (22) to stop supplying fuel to the first burner (42).

14. The start-up control method for a fuel cell system according to claim 13, characterized in that, The amount of water supplied by the water supply component (23) is reduced according to y=[(O2:C)*xr*z] / (r+1); Wherein, y is the amount of water supplied by the water supply component (23); (O2:C) is the minimum oxygen-to-carbon ratio during the operation of the reformer (45); x is the fuel flow rate entering the regenerator (44); r is the exhaust gas recirculation rate, which is the amount of gas output from the anode output end of the fuel cell stack (1) ejected back to the fuel input end of the regenerator (44) by the ejector (46) / the total amount of gas output from the anode output end of the fuel cell stack (1); z is the oxygen flow rate entering the anode input end of the fuel cell stack (1) when the fuel cell stack (1) is loaded.

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