Hydrogen supply system, control method and equipment for hydrogen fuel cell

Abstract

The present application provides a hydrogen supply system, control method and equipment for a hydrogen fuel cell, and relates to the field of fuel cell technology; the hydrogen supply system determines the hydrogen working mode according to the working current density of the stack and the pressure value of the gas storage tank through the control module, and in the intermittent hydrogen discharge mode, intermittently opens and closes the first control component and controls the ejector and the second control component to be in a disconnected state, so as to deliver the hydrogen source to the anode input terminal through the three-way valve; in the hydrogen half-cycle mode, the second control component and the ejector are controlled to be in a connected state and the first control component is controlled to be in a disconnected state, so as to deliver the hydrogen source to the anode input terminal through the ejector, and to withdraw the hydrogen stored in the gas storage tank through the ejector; in the hydrogen full-cycle mode, the first control component, the second control component and the ejector are controlled to be in a connected state, so as to deliver the hydrogen source to the anode input terminal through the ejector or the three-way valve. The above method can take into account both the recoverability of hydrogen and the voltage stability.

Description

Technical Field

[0001] The embodiments of the present application relate to but are not limited to the field of fuel cell technology, and in particular to a hydrogen supply system, control method and equipment for a hydrogen fuel cell. Background Art

[0002] For hydrogen fuel cells, the hydrogen on the anode side of the stack and the oxygen on the cathode side react chemically inside the stack to produce electricity and water. To ensure that the water inside the fuel cell can be removed smoothly and operate efficiently, the amount of hydrogen supplied on the anode side needs to be greater than the amount of hydrogen reacted. In the early days, it was mainly through direct discharge, which was reliable in operation and simple in control, but the utilization rate of hydrogen was low, resulting in waste of hydrogen and increased costs, and the high concentration of hydrogen in the tail discharge had safety hazards. Therefore, the usual practice in the prior art is to introduce an ejector as a power device for hydrogen circulation, and recycle the unconsumed hydrogen to improve the utilization rate of hydrogen. The ejector is a pure mechanical component based on the Venturi effect, which uses the pressure difference caused by the high-speed jet of the working fluid to inhale and discharge the ejection fluid, but its ejection range is limited, and it cannot meet the ejection under low-power conditions, resulting in poor voltage stability of the stack; therefore, how to take into account the recoverable rate of hydrogen and voltage stability when supplying hydrogen to the stack is a technical problem that needs to be solved urgently. Summary of the invention

[0003] The following is an overview of the subject matter described in detail herein. This overview is not intended to limit the scope of the claims. The present application provides a hydrogen supply system, control method and device for a hydrogen fuel cell, which can take into account both the recoverability of hydrogen and voltage stability.

[0004] In a first aspect, a hydrogen supply system for a hydrogen fuel cell according to an embodiment of the present application includes:

[0005] Battery stack;

[0006] A hydrogen supply assembly, the hydrogen supply assembly comprising an ejector and a three-way valve, the input end of the three-way valve being used to connect to a hydrogen source, the first output end of the three-way valve being connected to the high-voltage input end of the ejector, the second output end of the three-way valve being connected to the anode input end of the stack, and the output end of the ejector being connected to the anode input end of the stack;

[0007] A recycling component, the recycling component comprising a first control component, a gas-water separator, a gas storage tank and a second control component which are sequentially arranged in series, wherein a first end of the first control component away from the gas-water separator is connected to an anode output end of the stack, and the second control component is connected to a low-pressure input end of the ejector;

[0008] A control module, wherein the control module is used to:

[0009] Determine a hydrogen working mode according to the operating current density of the fuel cell stack and the pressure value of the gas storage tank, wherein the hydrogen working mode includes an intermittent hydrogen discharge mode, a hydrogen half-cycle mode and a hydrogen full-cycle mode;

[0010] In the intermittent hydrogen discharge mode, the first control element is intermittently opened and closed and the ejector and the second control element are controlled to be in an off state, so as to deliver the hydrogen source to the anode input end through the second end of the three-way valve;

[0011] In the hydrogen half-circulation mode, the second control element and the ejector are controlled to be in a connected state and the first control element is controlled to be in a disconnected state, so as to deliver a hydrogen source to the anode input end through the ejector, and to withdraw the hydrogen stored in the gas storage tank through the ejector;

[0012] In the hydrogen full circulation mode, the first control element, the second control element and the ejector are controlled to be in a connected state so as to deliver the hydrogen source to the anode input end through the ejector or the second end of the three-way valve.

[0013] In the second aspect, according to the control method of the hydrogen supply system of the hydrogen fuel cell proposed in the embodiment of the present application, the hydrogen supply system of the hydrogen fuel cell includes a fuel cell stack, a hydrogen supply component and a recycling component, the hydrogen supply component includes an ejector and a three-way valve, the input end of the three-way valve is used to connect a hydrogen source, the first output end of the three-way valve is connected to the high-pressure input end of the ejector, the second output end of the three-way valve is connected to the anode input end of the fuel cell stack, and the output end of the ejector is connected to the anode input end of the fuel cell stack; the recycling component includes a first control component, a gas-water separator, a gas storage tank and a second control component arranged in series in sequence, the first control component is connected to the anode output end of the fuel cell stack away from the first end of the gas-water separator, and the second control component is connected to the low-pressure input end of the ejector; the control method includes:

[0014] Determine a hydrogen working mode according to the operating current density of the fuel cell stack and the pressure value of the gas storage tank, wherein the hydrogen working mode includes an intermittent hydrogen discharge mode, a hydrogen half-cycle mode and a hydrogen full-cycle mode;

[0015] In the intermittent hydrogen discharge mode, the first control element is intermittently opened and closed and the ejector and the second control element are controlled to be in an off state, so as to deliver the hydrogen source to the anode input end through the second end of the three-way valve;

[0016] In the hydrogen half-circulation mode, the second control element and the ejector are controlled to be in a connected state and the first control element is controlled to be in a disconnected state, so as to deliver a hydrogen source to the anode input end through the ejector, and to withdraw the hydrogen stored in the gas storage tank through the ejector;

[0017] In the hydrogen full circulation mode, the first control element, the second control element and the ejector are controlled to be in a connected state so as to deliver the hydrogen source to the anode input end through the ejector or the second end of the three-way valve.

[0018] In a third aspect, according to the electronic device proposed in the embodiment of the present application, a control method for the hydrogen supply system of the hydrogen fuel cell as described in any one of the second aspects is executed.

[0019] The above-mentioned embodiments of the present application have at least the following beneficial effects: by increasing the gas storage tank and reducing the number of times the waste discharge end of the gas-water separator is opened and closed, the voltage stability during the hydrogen cycle is maintained. At the same time, by real-time detection of the working current density of the stack, the hydrogen working mode is determined, the gas storage tank is used to store hydrogen in the intermittent hydrogen discharge mode, and the hydrogen source is directly delivered to the anode input end through the second end of the three-way valve. In the hydrogen semi-cycle mode, the hydrogen stored in the gas storage tank is withdrawn through the ejector to participate in the hydrogen cycle to maintain the stability of the stack pressure under this working condition; therefore, the intermittent hydrogen discharge mode and the hydrogen semi-cycle mode are alternately operated to achieve the low-power working condition while ensuring the ejection effect of the ejector, while improving the utilization rate of the hydrogen cycle and maintaining the stability of the stack pressure; and in the hydrogen full cycle mode, the hydrogen is buffered by the gas storage tank to further ensure the ejection effect under high-power working conditions. Therefore, compared with the relevant technology, the embodiment of the present application can take into account the utilization efficiency of hydrogen and the timely discharge of excess water and nitrogen, and effectively maintain the stability of the stack voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide further understanding of the technical solution of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present application and do not constitute a limitation on the technical solution of the present application.

[0021] Figure 1 It is a module schematic diagram of the hydrogen supply system of the hydrogen fuel cell provided by the present application;

[0022] Figure 2 It is a structural schematic diagram of an embodiment of a hydrogen supply system of a hydrogen fuel cell provided by the present application;

[0023] Figure 3 It is a flow chart of a control method of a hydrogen supply system of a hydrogen fuel cell provided by the present application;

[0024] Figure 4 It is a logic control schematic diagram of an embodiment of a hydrogen supply system of a hydrogen fuel cell provided by the present application;

[0025] Figure 5 It is a schematic diagram of the control principle of an embodiment of the electronic device provided by the present application.

[0026] Reference numerals:

[0027] Battery stack 100,

[0028] Hydrogen supply assembly 200, ejector 210, three-way valve 220, first pressure sensor 230, proportional valve 240, third control element 250,

[0029] Circulation and recovery component 300, first control component 310, gas-water separator 320, gas storage tank 330, second control component 340, second pressure sensor 350, third pressure sensor 360,

[0030] Control module 500,

[0031] Exhaust and drain valve 610 , nitrogen concentration sensor 620 , water storage tank 630 , liquid level sensor 640 , mixer 650 . DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art belonging to the technical field of the present application. The terms used herein are only for the purpose of describing the embodiments of the present application and are not intended to limit the present application. The terms "first", "second", "third", "fourth", etc. (if present) in the specification of the present application and the above-mentioned drawings are used to distinguish similar objects, and need not be used to describe a specific order or sequential order.

[0034] In addition, the described features, structures or characteristics may be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present disclosure. However, those skilled in the art will appreciate that the technical solutions of the present disclosure may be practiced without one or more of the specific details, or other methods, components, devices, steps, etc. may be adopted. In other cases, known methods, devices, implementations or operations are not shown or described in detail to avoid blurring the various aspects of the present disclosure.

[0035] For hydrogen fuel cells, the hydrogen on the anode side of the stack and the oxygen on the cathode side react chemically inside the stack to generate electricity and water. To ensure that the water inside the fuel cell can be removed smoothly and operate efficiently, the amount of hydrogen supplied on the anode side needs to be greater than the amount of hydrogen reacted. In the early days, it was mainly discharged directly, which was reliable and simple to control, but the utilization rate of hydrogen was low, resulting in waste of hydrogen and increased costs, and the high concentration of hydrogen in the tail discharge posed a safety hazard. Although a circulation device can be provided in the prior art to realize the circulation of hydrogen, a large amount of liquid water generated by the reaction of hydrogen and oxygen exists in the cathode flow channel. Part of the liquid water flows out of the stack with the air, and the other part diffuses to the anode through the membrane electrode. If the exhaust system of the anode cannot discharge the liquid water in the anode flow channel in time, it will cause the liquid water to accumulate in the catalyst layer and gas diffusion layer of the anode, causing local flooding and causing the performance of the fuel cell catalyst to decay. At the same time, due to the influence of the concentration gradient, the nitrogen at the cathode will also diffuse to the anode through the membrane electrode, and the accumulation of nitrogen will cause local gas shortage at the anode, which will also cause the catalyst performance to decay. Therefore, when recovering hydrogen, how to accurately control and manage the separation and discharge of nitrogen and liquid water in the anode outlet exhaust gas without affecting the quality of the circulating hydrogen is an urgent problem to be solved. Existing circulation devices such as hydrogen circulation pumps, although they have active adjustability, fast response and a wide working range, have complex structures, high noise, parasitic power consumption and high costs. A circulation device such as an ejector is a pure mechanical component based on the Venturi effect, which uses the pressure difference caused by the high-speed jet of the working fluid to inhale and discharge the ejected fluid, but its ejection range is limited and cannot meet the ejection under low-power conditions, resulting in poor voltage stability of the stack; therefore, how to take into account the recoverable rate of hydrogen and voltage stability when supplying hydrogen to the stack is a technical problem to be solved. Based on this, the present application provides a hydrogen supply system, control method and equipment for a hydrogen fuel cell, which can take into account the recoverable rate of hydrogen and voltage stability.

[0036] Reference Figure 1 and Figure 2 As shown, the embodiment of the present application provides a hydrogen supply system for a hydrogen fuel cell, comprising:

[0037] Battery stack 100;

[0038] A hydrogen supply assembly 200, the hydrogen supply assembly 200 comprises an ejector 210 and a three-way valve 220, the input end of the three-way valve 220 is used to connect to a hydrogen source, the first output end of the three-way valve 220 is connected to the high-pressure input end of the ejector 210, the second output end of the three-way valve 220 is connected to the anode input end of the fuel cell stack 100, and the output end of the ejector 210 is connected to the anode input end of the fuel cell stack 100;

[0039] The recycling component 300 includes a first control component 310, a gas-water separator 320, a gas storage tank 330, and a second control component 340 which are sequentially arranged in series. The first end of the first control component 310 away from the gas-water separator 320 is connected to the anode output end of the fuel cell stack 100, and the second control component 340 is connected to the low-voltage input end of the ejector 210;

[0040] The control module 500 is used for:

[0041] Determine a hydrogen working mode according to the operating current density of the fuel cell stack 100 and the pressure value of the gas storage tank 330, wherein the hydrogen working mode includes an intermittent hydrogen discharge mode, a hydrogen half-cycle mode, and a hydrogen full-cycle mode;

[0042] In the intermittent hydrogen discharge mode, the first control element 310 is intermittently opened and closed and the ejector 210 and the second control element 340 are controlled to be in an off state, so as to deliver the hydrogen source to the anode input end through the second output end of the three-way valve 220;

[0043] In the hydrogen half-circulation mode, the second control element 340 and the ejector 210 are controlled to be in a connected state and the first control element 310 is controlled to be in a disconnected state, so as to deliver the hydrogen source to the anode input end through the ejector 210, and to withdraw the hydrogen stored in the gas storage tank 330 through the ejector 210;

[0044] In the hydrogen full circulation mode, the first control element 310 , the second control element 340 and the ejector 210 are controlled to be in a connected state so as to deliver the hydrogen source to the anode input end through the second output end of the ejector 210 or the three-way valve 220 .

[0045] Therefore, the voltage stability during the hydrogen circulation process is maintained by adding a gas storage tank 330 and reducing the number of times the exhaust end of the gas-water separator 320 is opened and closed. At the same time, the operating current density of the fuel cell stack 100 is detected in real time to determine the hydrogen working mode, and the gas storage tank 330 is used to store hydrogen in the intermittent hydrogen discharge mode, and the hydrogen source is directly delivered to the anode input end through the second end of the three-way valve 220. In the hydrogen half-cycle mode, the hydrogen stored in the gas tank 330 is drawn back through the ejector 210 to participate in the hydrogen cycle, so as to maintain the stability of the pressure of the fuel cell stack 100 under this working condition; therefore, by alternating the operation of the intermittent hydrogen discharge mode and the hydrogen half-cycle mode, the utilization rate of the hydrogen cycle is improved while maintaining the stability of the pressure of the fuel cell stack 100 under low-power conditions while ensuring the ejection effect of the ejector; and in the hydrogen full-cycle mode, the hydrogen is buffered by the gas tank 330 to further ensure the ejection effect under high-power conditions. Therefore, compared with the related art, the embodiment of the present application can take into account the utilization efficiency of hydrogen and the timely discharge of excess water and nitrogen, and effectively maintain the stability of the voltage of the fuel cell stack 100.

[0046] It should be noted that the tail gas discharged from the anode of the stack 100 contains unconsumed hydrogen, nitrogen and some liquid water droplets. The liquid water droplets and gas (such as hydrogen and nitrogen) can be separated by the gas-water separator 320. At the same time, an exhaust and drain valve 610 is provided at the exhaust end of the gas-water separator 320 to discharge the excess liquid water droplets and impurity gases (such as nitrogen) in the gas-water separator 320. However, the opening and closing of the exhaust and drain valve 610 will cause the pressure on the anode hydrogen side to fluctuate, and the large pressure fluctuation will affect the life and performance of the stack 100. Therefore, controlling the opening and closing cycle of the exhaust and drain valve 610 can ensure the stability of the voltage of the stack 100. The additional gas storage tank 330 can buffer and store hydrogen, which can reduce the influence of the exhaust and drain valve 610 on the pressure of the stack 100, thereby reducing the difficulty of controlling the opening and closing cycle of the exhaust and drain valve 610.

[0047] It should be noted that the on / off triggering conditions of the excess liquid water droplets and impurity gases in the gas-water separator 320 can be triggered by the voltage difference between the anode input terminal and the anode output terminal, such as Figure 2 As shown, the first pressure sensor 230 is used to detect the pressure on the anode input side, and the second pressure sensor 350 is used to detect the pressure on the anode output side. When the voltage drop between the first pressure sensor 230 and the second pressure sensor 350 meets the voltage drop threshold, the exhaust and drain valve 610 connected to the exhaust end of the gas-water separator 320 is controlled to start, so that liquid water droplets and impurity gases are discharged through the gas-water separator 320->exhaust and drain valve 610. It should be noted that in some embodiments, a water storage tank 630 is provided in the gas-water separator 320, and the exhaust end is provided on the water storage tank 630.

[0048] It should be noted that in the intermittent hydrogen discharge mode and the hydrogen half-cycle mode, the gas tank 330 is used to cache hydrogen. At this time, in the intermittent hydrogen discharge mode, the circulation path of hydrogen is hydrogen source->three-way valve 220->first pressure sensor 230->fuel stack 100->second pressure sensor 350->first control component 310->gas-water separator 320->third pressure sensor 360->gas tank 330; the circulation path of hydrogen in the hydrogen half-cycle mode is hydrogen source->three-way valve 220->ejector 210->first pressure sensor 230->fuel stack 100; and gas-water separator 320->third pressure sensor 360->gas tank 330->second control component 340->ejector 210->first pressure sensor 230->fuel stack 100.

[0049] It should be noted that the cathode reaction gas is generally not compressed air, and the reaction product is water, which is discharged with the flowing gas; Figure 2As shown, the reactants discharged from the cathode are mixed with the excess liquid water droplets and impurity gases discharged from the gas-water separator 320 and then enter the mixer 650 for discharge.

[0050] It should be noted that the ejector 210 has three inlet and outlet ports, corresponding to the high-pressure input end, the medium-pressure output end and the low-pressure input end, respectively. When the second control component 340 is started in the hydrogen semi-cycle mode, the low-pressure input end and the gas tank 330 will be connected, so as to utilize the Venturi effect to circulate and recycle hydrogen, and accelerate the speed of hydrogen recovery by the gas tank 330; when the hydrogen in the gas tank 330 reaches a certain concentration, it will participate in the hydrogen cycle in the Venturi effect, so that the hydrogen in the gas tank 330 and the three-way valve 220 are mixed and ejected, thereby ensuring the ejection effect in the hydrogen semi-cycle mode. In the intermittent hydrogen discharge mode, the hydrogen in the gas tank 330 is not enough to ensure the ejection effect of the ejector 210, so the ejector 210 is closed and only hydrogen is stored, and the hydrogen in the gas tank 330 is used to ensure the ejection effect of the ejector 210 when the intermittent hydrogen discharge mode is jumped out and the hydrogen semi-cycle mode is entered.

[0051] It should be noted that the pressure value of the gas tank 330 can be detected by the third pressure sensor 360. The third pressure sensor 360 can be set on the pipeline between the gas-water separator 320 and the gas tank 330, or it can be set inside the gas tank 330. In this regard, the embodiment of the present application does not limit the setting position of the third pressure sensor 360, and technical personnel in this field can selectively set it according to actual needs.

[0052] It should be noted that the operating current density refers to the amount of current passing through the fuel cell stack 100 per unit area.

[0053] It should be noted that intermittent opening and closing of the first control component 310 means repeatedly starting and closing the first control component 310 according to a preset cycle. For example, within 1S, with 0.1S as a cycle, the first control component 310 is closed in 0.1S, then the first control component 310 is started in 0.2S, and then the first control component 310 is closed in 0.3S, and so on, the first control component 310 is repeatedly opened and closed.

[0054] It should be noted that the first control element 310 is used to control the connection between the anode output terminal and the gas-water separator 320; the second control element 340 is used to control the connection between the gas storage tank 330 and the ejector 210. The first control element 310 and the second control element 340 can be set as control components such as solenoid valves. For example, Figure 2 As shown, the first control component 310 is configured as a solenoid valve, and the second control component 340 is configured as a stop valve.

[0055] It should be noted that in the hydrogen full circulation mode, the amount of hydrogen provided by the hydrogen source is large enough, and the ejector 210 can achieve a stable circulation function. Therefore, the recycled hydrogen is buffered by the gas storage tank 330, which can further maintain the voltage stability of the fuel cell stack 100.

[0056] It should be noted that, in some embodiments, the hydrogen supply system further includes a proportional valve 240 and a third control component 250. The proportional valve 240 is located between the third control component 250 and the three-way valve 220. The output end of the third control component 250 is connected to the hydrogen source, so that the hydrogen source can have a certain initial speed through the proportional valve 240 and the third control component 250. The third control component 250 can be set as a component for controlling gas flow, such as a solenoid valve, Figure 2 As shown, the third control component 250 is configured as a switch solenoid valve.

[0057] For example, Figure 2Taking the hydrogen supply system shown as an example, when the hydrogen working mode is determined to be the intermittent hydrogen discharge mode according to the operating current density of the fuel cell stack 100 and the pressure value of the gas tank 330, the first control component 310 is intermittently opened and closed, and the ejector 210 and the second control component 340 are closed. At this time, the hydrogen circulation path is: the third control component 250->proportional valve 240->three-way valve 220->first pressure sensor 230->fuel cell stack 100->second pressure sensor 350->first control component 310->gas-water separator 320->third pressure sensor 360->gas tank 330; the path for impurity gas and water management using the voltage drop threshold is: gas-water separator 320->exhaust and drain valve 610->mixer 650. According to the operating current density of the fuel cell stack 100 and the pressure value of the gas tank 330, it is determined that the hydrogen working mode is the hydrogen half-circulation mode, then the second control component 340 and the ejector 210 are started, and the first control component 310 is closed. At this time, the hydrogen circulation path is: the third control component 250->proportional valve 240->three-way valve 220->ejector 210->first pressure sensor 230->fuel cell stack 100 and gas-water separator 320->third pressure sensor 360->gas tank 330->second control component 340->ejector 210->first pressure sensor 230->fuel cell stack 100, and the voltage drop threshold is used to manage impurity gas and water: gas-water separator 320->exhaust and drain valve 610->mixer 650. According to the operating current density of the fuel cell stack 100 and the pressure value of the gas storage tank 330, it is determined that the hydrogen working mode is in the hydrogen full circulation mode, then the first control component 310, the second control component 340 and the ejector 210 are opened. At this time, the hydrogen circulation path is: use the third control component 250->proportional valve 240->three-way valve 220->ejector 210->first pressure sensor 230->fuel cell stack 100->second pressure sensor 350->first control component 310->gas-water separator 320->exhaust and drain valve 610->mixer 650 or the third control component 250->proportional valve 240->three-way valve 220->first pressure sensor 230->fuel cell stack 100->second pressure sensor 350->first control component 310->gas-water separator 320->exhaust and drain valve 610->mixer 650; the voltage drop threshold is used to manage impurity gas and water: gas-water separator 320->exhaust and drain valve 610->mixer 650. Therefore, the embodiment of the present application can realize stable operation of the fuel cell stack 100 mainly through intermittent hydrogen discharge when the pressure of the gas storage tank 330 is detected to be low under low power operation conditions. When the pressure of the gas storage tank 330 is detected to reach a certain pressure value, the second control component 340 and the three-way valve 220 are adjusted to close the intermittent hydrogen discharge, and the hydrogen half-cycle is realized through the operation of the ejector 210.In the high-power stage, the customized development of the ejector 210 at the power point can achieve stable hydrogen circulation at high power and perform a full hydrogen circulation mode. The storage tank does not manage hydrogen storage and withdrawal, but only plays a buffering role. To a certain extent, it solves the problem of direct hydrogen waste and poor low-power ejection effect of a single ejector 210.

[0058] It is understandable that the control module 500 is also used for:

[0059] Obtaining the operating current density and the pressure value of the gas storage tank 330 according to a preset detection cycle;

[0060] When the operating current density is greater than or equal to the current density threshold, the hydrogen working mode is determined to be the hydrogen full cycle mode;

[0061] When the operating current density is less than the current density threshold and the pressure value of the gas storage tank 330 is less than the first pressure threshold, the hydrogen working mode is determined to be the intermittent hydrogen discharge mode;

[0062] When the operating current density is less than the current density threshold and the pressure value of the gas storage tank 330 is greater than or equal to the first pressure threshold, it is determined that the hydrogen working mode is the hydrogen half-cycle mode.

[0063] Therefore, the hydrogen full cycle mode and the non-hydrogen full cycle mode are distinguished by the operating current density, and based on the pressure value of the gas tank 330, it is further determined whether the hydrogen working mode is the intermittent hydrogen discharge mode or the hydrogen half cycle mode, so that the gas tank 330 can be fully utilized for hydrogen recovery management.

[0064] By periodically acquiring the operating current density and the pressure value of the gas tank 330, corresponding hydrogen recovery management can be performed in real time according to the actual operating conditions of the fuel cell stack 100, thereby further solving the problems of direct hydrogen waste and poor low-power injection effect of the single ejector 210.

[0065] It is understandable that the exhaust end of the gas-water separator 320 is connected to the gas storage tank 330; the exhaust end of the gas-water separator 320 is provided with an exhaust and drain valve 610; the control module 500 is also used for:

[0066] Obtaining a voltage drop of the battery stack 100;

[0067] The exhaust and drainage valve 610 is controlled to be opened or closed according to the voltage drop, the liquid level value of the gas-water separator 320 and the nitrogen concentration value.

[0068] By individually controlling the excess water and impurity gas in the gas-water separator 320 according to the voltage drop, the liquid level value of the gas-water separator 320 and the nitrogen concentration value, decoupling from the hydrogen circulation process can be achieved, and the control process is simpler and more reliable.

[0069] It should be noted that when the water storage tank 630 is provided in the gas-water separator 320, the liquid level value of the gas-water separator 320 indicates the liquid level of the water storage tank 630, and a liquid level sensor 640 is provided in the water storage tank 630. When the gas-water separator 320 is not provided with a separate water storage tank 630, the liquid level value indicates the liquid level of the separation chamber in the gas-water separator 320.

[0070] For example, Figure 2 As shown, the voltage drop can be obtained according to the first pressure sensor 230 and the second pressure sensor 350. The liquid level value can be determined according to the liquid level sensor 640 disposed in the gas-water separator 320; the nitrogen concentration value can be determined according to the nitrogen concentration sensor 620 disposed in the gas-water separator 320.

[0071] It is understandable that, in the intermittent hydrogen discharge mode, the control module 500 is also used to:

[0072] When the voltage drop is greater than or equal to a preset first voltage drop threshold, the exhaust and drain valve 610 is opened;

[0073] When the voltage drop is less than the first voltage drop threshold and the liquid level value is greater than the liquid level threshold value, the exhaust and drain valve 610 is opened, otherwise the exhaust and drain valve 610 is closed;

[0074] When the voltage drop is greater than or equal to the first voltage drop threshold and the nitrogen concentration is less than or equal to the preset first concentration value, the exhaust and drain valve 610 is closed, otherwise the exhaust and drain valve 610 is kept in a connected state.

[0075] It should be noted that the first voltage drop threshold represents the minimum voltage difference that affects the voltage stability of the stack 100 when the voltage drop is less than the current density threshold. The greater the voltage drop, the worse the stability of the stack 100.

[0076] The first concentration value represents the minimum nitrogen concentration that affects the voltage stability of the fuel cell stack 100 when the current density is less than the threshold value. The higher the nitrogen concentration, the worse the stability of the fuel cell stack 100.

[0077] By controlling the start and stop of the exhaust and drain valve 610 based on the voltage drop and the nitrogen concentration, the hydrogen recovery efficiency can be further increased while ensuring the stability of the voltage of the fuel cell stack 100.

[0078] It is understandable that, in the hydrogen half-cycle mode, the control module 500 is also used for:

[0079] When the voltage drop is greater than or equal to the preset first voltage drop threshold, open the exhaust drain valve 610;

[0080] When the voltage drop is greater than or equal to the first voltage drop threshold and the nitrogen concentration is less than or equal to the preset first concentration value, the exhaust and drain valve 610 is closed, otherwise the exhaust and drain valve 610 is kept in a connected state;

[0081] After the exhaust and drain valve 610 is closed, when the pressure value of the gas storage tank 330 is greater than the second pressure threshold, the process returns to the step of controlling the second control component 340 and the ejector 210 to be in a connected state and controlling the first control component 310 to be in a disconnected state in the hydrogen half-circulation mode.

[0082] It should be noted that the second pressure threshold represents the minimum pressure value of the gas tank 330 when the ejection effect of the ejector 210 reaches the expected value; by setting the first pressure threshold, the intermittent hydrogen discharge mode can be entered to store hydrogen, and through the first pressure threshold and the second pressure threshold, the probability of opening and closing the ejector 210 can be reduced.

[0083] It should be noted that when the pressure value of the gas tank 330 is less than or equal to the second pressure threshold, the process jumps to the step of determining the hydrogen working mode according to the operating current density of the fuel cell stack 100 and the pressure value of the gas tank 330, so that when the conditions are not met, the specific execution steps can be re-determined based on the current operating current density and the pressure value of the gas tank 330.

[0084] It is understandable that, in the hydrogen full cycle mode, the control module 500 is also used for:

[0085] When the voltage drop is greater than or equal to a preset second voltage drop threshold, the exhaust and drain valve 610 is opened; wherein the second voltage drop threshold is greater than the first voltage drop threshold;

[0086] When the voltage drop is less than the second voltage drop threshold and the liquid level value is greater than the liquid level threshold value, the exhaust and drain valve 610 is opened, otherwise the exhaust and drain valve is closed;

[0087] When the voltage drop is greater than or equal to the second voltage drop threshold and the nitrogen concentration is less than or equal to the preset second concentration value, the exhaust and drain valve 610 is closed, otherwise the exhaust and drain valve is kept in a connected state; the second concentration value is greater than the first concentration value.

[0088] It should be noted that the second voltage drop threshold represents the minimum voltage difference that affects the voltage stability of the fuel cell stack 100 under high power conditions.

[0089] The second concentration value represents the minimum nitrogen concentration that affects the voltage stability of the fuel cell stack 100 under high power conditions.

[0090] Therefore, by setting different voltage drop thresholds and nitrogen concentration thresholds under different working conditions, the voltage stability under different working conditions can be further ensured.

[0091] Understandably, referring to Figure 3 As shown, a control method for a hydrogen supply system of a hydrogen fuel cell provided in an embodiment of the present application is applied to the hydrogen supply system of the above-mentioned hydrogen fuel cell, and the control method includes:

[0092] Step S100, determining a hydrogen working mode according to the working current density of the fuel cell stack and the pressure value of the gas storage tank, the hydrogen working mode including an intermittent hydrogen discharge mode, a hydrogen half-cycle mode and a hydrogen full-cycle mode;

[0093] Step S200, in the intermittent hydrogen discharge mode, intermittently opening and closing the first control element and controlling the ejector and the second control element to be in an off state, so as to transport the hydrogen source to the anode input end through the second output end of the three-way valve;

[0094] Step S300, in the hydrogen half-circulation mode, controlling the second control element and the ejector to be in a connected state and controlling the first control element to be in a disconnected state, so as to deliver the hydrogen source to the anode input end through the ejector, and to store the hydrogen separated by the gas-water separator in the gas storage tank through the ejector;

[0095] Step S400: In the hydrogen full circulation mode, the first control element, the second control element and the ejector are controlled to be in a connected state, so as to deliver the hydrogen source to the anode input end through the second output end of the ejector or the three-way valve.

[0096] Therefore, by increasing the gas storage tank and reducing the number of times the waste discharge end of the gas-water separator is opened and closed, the voltage stability during the hydrogen cycle is maintained. At the same time, by real-time detection of the working current density of the stack, the hydrogen working mode is determined, the gas storage tank is used to store hydrogen in the intermittent hydrogen discharge mode, and the hydrogen source is directly delivered to the anode input end through the second end of the three-way valve. In the hydrogen semi-cycle mode, the hydrogen stored in the gas storage tank is withdrawn through the ejector to participate in the hydrogen cycle to maintain the stability of the stack pressure under this working condition; therefore, the intermittent hydrogen discharge mode and the hydrogen semi-cycle mode are alternately operated to achieve low-power conditions while ensuring the ejection effect of the ejector, while improving the utilization rate of the hydrogen cycle and maintaining the stability of the stack pressure; and in the hydrogen full cycle mode, the hydrogen is buffered by the gas storage tank to further ensure the ejection effect under high-power conditions. Therefore, compared with the relevant technology, the embodiment of the present application can take into account the utilization efficiency of hydrogen and the timely discharge of excess water and nitrogen, and effectively maintain the stability of the stack voltage.

[0097] It should be noted that the pressure value of the gas tank represents the capacity of hydrogen stored in the gas tank. The more hydrogen there is in the gas tank, the higher the probability that the ejector can work normally. Therefore, by introducing the pressure value of the gas tank, the probability of the ejector working normally can be further ensured.

[0098] It should be noted that the demand for hydrogen is different under different working conditions, and the capacity of recyclable hydrogen is different. Therefore, by introducing the working current density, the efficiency of hydrogen recovery can be further achieved by selecting different hydrogen circulation paths. Therefore, those skilled in the art can selectively set the judgment conditions of the working current density and the pressure value of the gas storage tank when entering the intermittent hydrogen discharge mode, the hydrogen half-circulation mode and the hydrogen full-circulation mode according to actual needs.

[0099] It is understandable that in step S100, the hydrogen working mode is determined according to the working current density of the fuel cell stack and the pressure value of the gas storage tank, including:

[0100] Obtain the operating current density and the pressure value of the gas tank according to the preset detection cycle;

[0101] When the operating current density is greater than or equal to the current density threshold, the hydrogen working mode is determined to be the hydrogen full cycle mode;

[0102] When the operating current density is less than the current density threshold and the pressure value of the gas storage tank is less than the first pressure threshold, the hydrogen working mode is determined to be the intermittent hydrogen discharge mode;

[0103] When the operating current density is less than the current density threshold and the pressure value of the gas storage tank is greater than or equal to the first pressure threshold, it is determined that the hydrogen working mode is the hydrogen half-cycle mode.

[0104] It is understandable that the exhaust end of the gas-water separator is connected to the gas storage tank; the exhaust end of the gas-water separator is provided with an exhaust and drain valve; the control method also includes:

[0105] Obtain the voltage drop of the fuel cell stack and the voltage drop threshold corresponding to the hydrogen working mode;

[0106] When the voltage drop is greater than the voltage drop threshold, the exhaust and drain valve is controlled to open;

[0107] According to the liquid level value and / or nitrogen concentration value of the gas-water separator, the exhaust and drain valves are controlled to be closed.

[0108] For example, refer to Figure 4 A flow chart of a control method for a hydrogen supply system according to an embodiment of the present application is described, wherein the first control element is set as a hydrogen exhaust solenoid valve, the second control element is set as a shut-off valve, and the current density threshold is set to 1.3A / cm2. Figure 4 As shown:

[0109] Under low power conditions (i.e., operating current density is less than 1.3A / cm2; the storage tank is used for recovery and storage):

[0110] When the pressure value of the gas storage tank detected by the third pressure sensor is lower than the set first pressure threshold (such as 0.3 barg), the intermittent hydrogen discharge mode is entered, the hydrogen discharge solenoid valve is started intermittently to realize the intermittent hydrogen discharge process, the gas storage tank collects the gas at the outlet of the gas-water separator, and the stop valve is closed.

[0111] Monitor the pressure value of the third pressure sensor. When the pressure is higher than the set first pressure threshold of 0.3 barg, enter the hydrogen semi-circulation mode, open the stop valve, switch the three-way valve, open the hydrogen ejector, and use the Venturi effect to circulate and recover hydrogen. When the monitored pressure is lower than the set second pressure threshold of 0.1 barg, exit the hydrogen semi-circulation mode, close the stop valve, switch the three-way valve, the ejector does not work, and returns to the intermittent hydrogen discharge mode.

[0112] The opening and closing of the entire hydrogen cycle is realized by controlling the stop valve and the three-way valve at the same time according to the real-time pressure value detected by the third pressure sensor, while the process of draining and exhausting impurity gases controls the opening and closing time of the exhaust and drain solenoid valve according to the voltage drop value, the liquid level sensor and the signal of the nitrogen concentration sensor. The sensor signal of the entire anode hydrogen cycle control process is decoupled and independently controlled, which is simple and reliable.

[0113] Under high power conditions (i.e., operating current density is greater than or equal to 1.3A / cm2; the storage tank only serves as a buffer):

[0114] Entering into the hydrogen full cycle mode, the ejector connectivity is in good condition, and by detecting the voltage of the fuel cell stack, the process of water and impurity exhaust gas controls the opening and closing time of the exhaust and drainage solenoid valve according to the signals of the voltage drop threshold, liquid level sensor and nitrogen concentration sensor. The sensor signal is decoupled, the control is simple, and the stability of the fuel cell stack voltage is effectively maintained.

[0115] In other embodiments, the present application also provides an electronic device for executing the above-mentioned control method of the hydrogen supply system of the hydrogen fuel cell.

[0116] like Figure 5 As shown, the electronic equipment includes:

[0117] One or more processors 801;

[0118] The memory 802 stores one or more programs. When the one or more programs are executed by the one or more processors 801, the one or more processors 801 implement the method provided in any embodiment of the present application.

[0119] The memory 802 is a non-transient network system that can be used to store non-transient software programs and non-transient computer executable programs. In addition, the memory 802 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some embodiments, the memory 802 may optionally include a memory 802 remotely arranged relative to the processor 801, and these remote memories 802 may be connected to the processor 801 via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0120] The memory 802 can be implemented in the form of a read-only memory (ROM), a static storage device, a dynamic storage device, or a random access memory (RAM). The memory 802 can store an operating system and other application programs. When the technical solutions provided in the embodiments of this specification are implemented by software or firmware, the relevant program codes are stored in the memory 802, and the processor 801 calls and executes the methods of the embodiments of this application.

[0121] The processor 801 can be implemented by a general-purpose CPU (Central Processing Unit), a microprocessor, an application-specific integrated circuit (Application Specific Integrated Circuit, ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solution provided in the embodiment of the present application.

[0122] In some embodiments, the electronic device further comprises:

[0123] Input / output interface, used to realize information input and output;

[0124] Communication interface, used to realize communication interaction between this device and other devices. Communication can be realized through wired methods (such as USB, network cable, etc.) or wireless methods (such as mobile network, WIFI, Bluetooth, etc.);

[0125] A bus that transmits information between various components of the device (e.g., processor 801, memory 802, input / output interfaces, and communication interfaces);

[0126] The processor 801 , the memory 802 , the input / output interface and the communication interface can be connected to each other in communication within the device via a bus.

[0127] The above is a specific description of the preferred implementation of the present application, but the present application is not limited to the above-mentioned implementation mode. Technical personnel familiar with the field can also make various equivalent deformations or substitutions without violating the spirit of the present application. These equivalent deformations or substitutions are all included in the scope defined by the claims of the present application.

Claims

1. A hydrogen supply system for a hydrogen fuel cell, characterized in that: The hydrogen supply system comprises: Battery stack; A hydrogen supply assembly, the hydrogen supply assembly comprising an ejector and a three-way valve, the input end of the three-way valve being used to connect to a hydrogen source, the first output end of the three-way valve being connected to the high-voltage input end of the ejector, the second output end of the three-way valve being connected to the anode input end of the stack, and the output end of the ejector being connected to the anode input end of the stack; A recycling component, the recycling component comprising a first control component, a gas-water separator, a gas storage tank and a second control component which are sequentially arranged in series, wherein a first end of the first control component away from the gas-water separator is connected to an anode output end of the stack, and the second control component is connected to a low-pressure input end of the ejector; A control module, wherein the control module is used to: Determine a hydrogen working mode according to the operating current density of the fuel cell stack and the pressure value of the gas storage tank, wherein the hydrogen working mode includes an intermittent hydrogen discharge mode, a hydrogen half-cycle mode and a hydrogen full-cycle mode; In the intermittent hydrogen discharge mode, the first control element is intermittently opened and closed and the ejector and the second control element are controlled to be in an off state, so as to deliver the hydrogen source to the anode input end through the second end of the three-way valve; In the hydrogen half-circulation mode, the second control element and the ejector are controlled to be in a connected state and the first control element is controlled to be in a disconnected state, so as to deliver a hydrogen source to the anode input end through the ejector, and to withdraw the hydrogen stored in the gas storage tank through the ejector; In the hydrogen full circulation mode, the first control element, the second control element and the ejector are controlled to be in a connected state so as to deliver the hydrogen source to the anode input end through the ejector or the second end of the three-way valve.

2. The hydrogen supply system of a hydrogen fuel cell according to claim 1, characterized in that: The control module is also used for: Acquiring the operating current density and the pressure value of the gas storage tank according to a preset detection cycle; When the operating current density is greater than or equal to a current density threshold, determining that the hydrogen operating mode is a hydrogen full cycle mode; When the operating current density is less than the current density threshold and the pressure value of the gas storage tank is less than a first pressure threshold, determining that the hydrogen working mode is an intermittent hydrogen discharge mode; When the operating current density is less than the current density threshold and the pressure value of the gas storage tank is greater than or equal to the first pressure threshold, it is determined that the hydrogen working mode is the hydrogen half-cycle mode.

3. The hydrogen supply system of a hydrogen fuel cell according to claim 1, characterized in that: The exhaust end of the gas-water separator is connected to the gas storage tank; the exhaust end of the gas-water separator is provided with an exhaust and drain valve; the control module is also used for: Obtaining a voltage drop of the battery stack; The exhaust and water drainage valve is controlled to be opened or closed according to the voltage drop, the liquid level value of the gas-water separator and the nitrogen concentration value.

4. The hydrogen supply system of the hydrogen fuel cell according to claim 3, characterized in that: In the intermittent hydrogen discharge mode, the control module is further configured to: When the voltage drop is greater than or equal to a preset first voltage drop threshold, opening the exhaust and drain valve; When the voltage drop is less than a first voltage drop threshold and the liquid level value is greater than a liquid level threshold value, the exhaust and drain valve is opened; otherwise, the exhaust and drain valve is closed; When the voltage drop is greater than or equal to the first voltage drop threshold and the nitrogen concentration is less than or equal to a preset first concentration value, the exhaust and drain valve is closed; otherwise, the exhaust and drain valve is kept in a connected state.

5. The hydrogen supply system of a hydrogen fuel cell according to claim 3, characterized in that: In the hydrogen half-cycle mode, the control module is further configured to: When the voltage drop is greater than or equal to a preset first voltage drop threshold, opening the exhaust and drain valve; When the voltage drop is greater than or equal to the first voltage drop threshold and the nitrogen concentration is less than or equal to a preset first concentration value, the exhaust and drain valve is closed, otherwise the exhaust and drain valve is kept in a connected state; After the exhaust and drain valve is closed, when the pressure value of the gas storage tank is greater than the second pressure threshold, the process returns to the step of controlling the second control component and the ejector to be in a connected state and controlling the first control component to be in a disconnected state in the hydrogen half-circulation mode.

6. The hydrogen supply system of a hydrogen fuel cell according to claim 4, characterized in that: In the hydrogen full cycle mode, the control module is further used for: When the voltage drop is greater than or equal to a preset second voltage drop threshold, the exhaust and drain valve is opened; wherein the second voltage drop threshold is greater than the first voltage drop threshold; When the voltage drop is less than the second voltage drop threshold and the liquid level value is greater than the liquid level threshold value, the exhaust and drain valve is opened, otherwise the exhaust and drain valve is closed; When the voltage drop is greater than or equal to the second voltage drop threshold and the nitrogen concentration is less than or equal to a preset second concentration value, the exhaust and drain valve is closed, otherwise the exhaust and drain valve is kept in a connected state; the second concentration value is greater than the first concentration value.

7. A method for controlling a hydrogen supply system of a hydrogen fuel cell, characterized in that: The hydrogen supply system of the hydrogen fuel cell comprises a fuel cell stack, a hydrogen supply component and a recycling component, wherein the hydrogen supply component comprises an ejector and a three-way valve, wherein the input end of the three-way valve is used to connect a hydrogen source, the first output end of the three-way valve is connected to the high-voltage input end of the ejector, the second output end of the three-way valve is connected to the anode input end of the fuel cell stack, and the output end of the ejector is connected to the anode input end of the fuel cell stack; the recycling component comprises a first control component, a gas-water separator, a gas storage tank and a second control component which are sequentially arranged in series, wherein the first end of the first control component away from the gas-water separator is connected to the anode output end of the fuel cell stack, and the second control component is connected to the low-voltage input end of the ejector; the control method comprises: Determine a hydrogen working mode according to the operating current density of the fuel cell stack and the pressure value of the gas storage tank, wherein the hydrogen working mode includes an intermittent hydrogen discharge mode, a hydrogen half-cycle mode and a hydrogen full-cycle mode; In the intermittent hydrogen discharge mode, the first control element is intermittently opened and closed and the ejector and the second control element are controlled to be in an off state, so as to deliver the hydrogen source to the anode input end through the second end of the three-way valve; In the hydrogen half-circulation mode, the second control element and the ejector are controlled to be in a connected state and the first control element is controlled to be in a disconnected state, so as to deliver a hydrogen source to the anode input end through the ejector, and to withdraw the hydrogen stored in the gas storage tank through the ejector; In the hydrogen full circulation mode, the first control element, the second control element and the ejector are controlled to be in a connected state so as to deliver the hydrogen source to the anode input end through the ejector or the second end of the three-way valve.

8. The control method of the hydrogen supply system of the hydrogen fuel cell according to claim 7, characterized in that: The determining of the hydrogen working mode according to the working current density of the fuel cell stack and the pressure value of the gas storage tank includes: Acquiring the operating current density and the pressure value of the gas storage tank according to a preset detection cycle; When the operating current density is greater than or equal to a current density threshold, determining that the hydrogen operating mode is a hydrogen full cycle mode; When the operating current density is less than the current density threshold and the pressure value of the gas storage tank is less than a first pressure threshold, determining that the hydrogen working mode is an intermittent hydrogen discharge mode; When the operating current density is less than the current density threshold and the pressure value of the gas storage tank is greater than or equal to the first pressure threshold, it is determined that the hydrogen working mode is the hydrogen half-cycle mode.

9. The control method of the hydrogen supply system of the hydrogen fuel cell according to claim 7, characterized in that: The exhaust end of the gas-water separator is connected to the gas storage tank; the exhaust end of the gas-water separator is provided with an exhaust and drain valve; The control method further comprises: Obtaining a voltage drop of the fuel cell stack and a voltage drop threshold corresponding to the hydrogen working mode; When the voltage drop is greater than the voltage drop threshold, controlling the exhaust and drain valve to open; The exhaust and drain valve is controlled to be closed according to the liquid level value and / or nitrogen concentration value of the gas-water separator.

10. An electronic device, characterized in that: Execute the control method of the hydrogen supply system of the hydrogen fuel cell as described in any one of claims 7 to 9.

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