Fuel cell anode pressure control method and device
By calculating and real-time compensation to control the pressure value in the fuel cell system, the problem of anode pressure fluctuation in the tail hydrogen recirculation mode is solved, and the service life of the fuel cell is extended.
Patent Information
- Application Number
- CN202411236712.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-04
- Publication Date
- 2024-12-17
AI Technical Summary
The fuel cell system in tail hydrogen recirculation mode fluctuates greatly when the exhaust valve is opened, resulting in unstable stack performance and the proton exchange membrane is damaged by mechanical pressure, which affects the battery life.
By calculating the internal hydrogen consumption pressure of the stack, the DV valve exhaust hydrogen pressure and the hydrogen circulation pump feedback pressure, the pressure value of the control proportional valve is compensated in real time to reduce the fluctuation of the anode pressure when the exhaust valve is opened.
It effectively reduces the fluctuation of the anode pressure when the exhaust valve is opened and extends the life of the fuel cell.
Smart Images
Figure CN119153736A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of fuel cells, and in particular to a method and device for controlling anode pressure of a fuel cell. Background Art
[0002] During the operation of the fuel cell system in the tail hydrogen recirculation mode, nitrogen permeation will occur at the anode, causing the anode hydrogen concentration to decrease. Water diffusion will occur inside the PEMFC stack during the reaction process. Hydrogen protons and electrons reach the cathode catalyst layer and react with oxygen to produce water, while no water is produced on the anode side. Therefore, there is a concentration difference of water on both sides of the membrane. The water on the cathode side will diffuse through the membrane to the anode side, causing local flooding of the anode. Therefore, the tail hydrogen recirculation mode requires the exhaust valve to be opened regularly to discharge part of the exhaust gas, and the other part is circulated to the intake pipeline through the hydrogen circulation pump; the drain valve needs to be opened regularly to discharge liquid water to ensure that the fuel cell operates in a normal state.
[0003] In the process of opening the exhaust valve to exhaust, the anode intake pressure will fluctuate violently, resulting in unstable performance of the battery stack. The proton exchange membrane will be subjected to repeated mechanical pressure, causing damage to the membrane and affecting the battery life. Summary of the invention
[0004] In view of the above problems, the present invention is proposed to provide a method and device for controlling the anode pressure of a fuel cell, which can reduce the fluctuation of the anode pressure when the exhaust valve is opened and extend the life of the fuel cell.
[0005] According to a first aspect of the present invention, a method for controlling anode pressure of a fuel cell is provided, comprising:
[0006] When the DV valve is open, obtain the current density of the battery stack, the number of cells, the effective active area of the battery, the anode volume, the gas temperature of the anode side reaction, the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the gas temperature flowing into the DV valve, the pressure ratio of the hydrogen circulation pump, the speed of the hydrogen circulation pump and the gas temperature flowing into the hydrogen circulation pump;
[0007] Calculating the hydrogen pressure consumed inside the stack according to the current density of the stack, the number of cells, the effective active area of the cell, the anode volume and the gas temperature of the anode-side reaction;
[0008] Calculate the hydrogen pressure discharged from the DV valve according to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the anode volume and the gas temperature flowing into the DV valve;
[0009] Calculating the hydrogen feedback pressure fed back to the anode inlet by the hydrogen circulation pump according to the pressure ratio value of the hydrogen circulation pump, the rotation speed of the hydrogen circulation pump and the temperature of the gas flowing into the hydrogen circulation pump;
[0010] The pressure value of the control proportional valve is compensated in real time according to the preset initial value of the anode pressure of the control proportional valve opening, the hydrogen pressure consumed inside the fuel cell stack, the exhaust hydrogen pressure of the DV valve and the hydrogen feedback pressure.
[0011] Optionally, the calculating the hydrogen pressure consumed inside the battery stack according to the current density of the battery stack, the number of battery cells, the effective active area of the battery, the anode volume and the gas temperature of the anode-side reaction includes:
[0012] Calculating the flow rate of hydrogen consumed by the reaction in the battery stack according to the current density of the battery stack, the number of battery cells, and the effective active area of the battery;
[0013] The pressure of hydrogen consumed in the fuel cell stack is calculated based on the hydrogen flow rate consumed in the reaction in the fuel cell stack, the gas temperature of the anode side reaction, the hydrogen gas constant, and the anode volume.
[0014] Optionally, the calculating the flow rate of hydrogen consumed by the reaction in the battery stack according to the current density of the battery stack, the number of battery cells, and the effective active area of the battery includes:
[0015] According to the current density of the battery stack, the number of battery cells, and the effective active area of the battery, the hydrogen flow rate consumed by the reaction in the battery stack is calculated by the following formula:
[0016]
[0017] Among them, Mreact is the hydrogen flow consumed by the reaction in the battery stack, N is the number of battery cells, and M H2 is the molar mass of hydrogen, A act is the effective active area of the battery, F is the Faraday constant, i stack is the current density of the battery stack.
[0018] Optionally, the calculating the pressure of hydrogen consumed in the fuel cell stack according to the hydrogen flow consumed in the reaction in the fuel cell stack, the gas temperature of the anode side reaction, the hydrogen gas constant, and the anode volume includes:
[0019] The hydrogen pressure consumed in the stack is calculated according to the hydrogen flow rate consumed in the reaction in the stack, the gas temperature of the anode side reaction, the hydrogen gas constant, and the anode volume by the following formula:
[0020]
[0021] Where Preact is the hydrogen pressure consumed inside the stack, Mreact is the hydrogen flow consumed by the reaction inside the stack, R is the hydrogen gas constant, T1 is the gas temperature of the anode side reaction, V an is the anode volume, i stack is the current density of the battery stack, t0 is the opening time of the DV valve, t is the current time and t is less than the closing time of the DV valve.
[0022] Optionally, the calculating the discharge hydrogen pressure of the DV valve according to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the anode volume and the gas temperature flowing into the DV valve comprises:
[0023] Calculate the flow rate of hydrogen in the gas discharged from the DV valve according to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, and the gas temperature flowing into the DV valve;
[0024] The hydrogen pressure discharged from the DV valve is calculated according to the flow rate of hydrogen in the gas discharged from the DV valve, the temperature of the gas flowing into the DV valve, and the volume of the anode.
[0025] Optionally, the calculating the flow rate of hydrogen in the gas discharged from the DV valve according to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, and the gas temperature flowing into the DV valve comprises:
[0026] According to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, and the gas temperature flowing into the DV valve, the flow rate of hydrogen in the gas discharged from the DV valve is calculated by the following formula:
[0027]
[0028] Among them, M DV is the flow rate of hydrogen in the exhaust gas from the DV valve, C d is the valve flow coefficient, A t is the valve flow cross-sectional area, p DV,in is the gas pressure flowing into the DV valve, p DV,out is the gas pressure flowing out of the DV valve, T2 is the gas temperature flowing into the DV valve, γ is the adiabatic coefficient of the gas, and R is the hydrogen gas constant.
[0029] Optionally, the calculating the hydrogen pressure discharged from the DV valve according to the flow rate of hydrogen in the gas discharged from the DV valve, the temperature of the gas flowing into the DV valve, and the volume of the anode includes:
[0030] According to the partial pressure of hydrogen in the gas discharged from the DV valve, the temperature of the gas flowing into the DV valve, and the volume of the anode, the hydrogen pressure discharged from the DV valve is calculated by the following formula:
[0031]
[0032] Among them, P DV is the hydrogen pressure discharged from the DV valve, k is the hydrogen-nitrogen ratio in the gas discharged from the DV valve, T2 is the gas temperature flowing into the DV valve, R is the hydrogen gas constant, V an is the anode volume, MDV is the flow rate of hydrogen in the exhaust gas from the DV valve, t0 is the opening time of the DV valve, t is the current time and t is less than the closing time of the DV valve.
[0033] According to a second aspect of the present invention, there is provided a fuel cell anode pressure control device, comprising:
[0034] The acquisition module is used to obtain the current density of the battery stack, the number of cells, the effective active area of the battery, the anode volume, the gas temperature of the anode side reaction, the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the gas temperature flowing into the DV valve, the pressure ratio of the hydrogen circulation pump, the speed of the hydrogen circulation pump and the gas temperature flowing into the hydrogen circulation pump when the DV valve is opened;
[0035] A first calculation module is used to calculate the pressure of hydrogen consumed inside the battery stack according to the current density of the battery stack, the number of battery cells, the effective active area of the battery, the anode volume and the gas temperature of the anode side reaction;
[0036] A second calculation module is used to calculate the discharge hydrogen pressure of the DV valve according to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the anode volume and the gas temperature flowing into the DV valve;
[0037] A third calculation module is used to calculate the hydrogen feedback pressure fed back to the anode inlet by the hydrogen circulation pump according to the pressure ratio value of the hydrogen circulation pump, the rotation speed of the hydrogen circulation pump and the temperature of the gas flowing into the hydrogen circulation pump;
[0038] The compensation module is used to compensate the pressure value of the control proportional valve in real time according to the preset initial value of the anode pressure of the control proportional valve opening, the hydrogen pressure consumed inside the fuel cell stack, the exhaust hydrogen pressure of the DV valve and the hydrogen feedback pressure.
[0039] According to a third aspect of the present invention, a controller is provided, the controller comprising: a memory, a processor and a computer program stored in the memory and executable on the processor, the processor executing the above-mentioned fuel cell anode pressure control method.
[0040] According to a fourth aspect of the present invention, a vehicle is provided, the vehicle comprising a vehicle body and a controller installed in the vehicle body, wherein the controller executes the aforementioned fuel cell anode pressure control method.
[0041] The above one or more technical solutions in the embodiments of this specification have at least the following technical effects:
[0042] The embodiments of the present specification provide a method and device for controlling the anode pressure of a fuel cell. When the DV valve is opened, the current density of the fuel cell stack, the number of cells, the effective active area of the cells, the anode volume, the gas temperature of the anode side reaction, the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the gas temperature flowing into the DV valve, the pressure ratio of the hydrogen circulation pump, the speed of the hydrogen circulation pump and the gas temperature flowing into the hydrogen circulation pump are obtained; the hydrogen consumption inside the fuel cell stack is calculated based on the current density of the fuel cell stack, the number of cells, the effective active area of the cells, the anode volume and the gas temperature of the anode side reaction. pressure; calculate the hydrogen pressure discharged from the DV valve according to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the anode volume and the gas temperature flowing into the DV valve; calculate the hydrogen feedback pressure fed back to the anode inlet by the hydrogen circulation pump according to the pressure ratio of the hydrogen circulation pump, the speed of the hydrogen circulation pump and the gas temperature flowing into the hydrogen circulation pump; perform real-time compensation for the pressure value of the control proportional valve according to the preset anode pressure initial value of the control proportional valve opening, the hydrogen pressure consumed inside the fuel cell stack, the hydrogen pressure discharged from the DV valve and the hydrogen feedback pressure. This can reduce the fluctuation of the anode pressure when the exhaust valve is opened and extend the life of the fuel cell.
[0043] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS
[0044] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Also, throughout the accompanying drawings, the same reference figures are used to represent the same components. In the drawings:
[0045] Figure 1 A flow chart of a fuel cell anode pressure control method in an embodiment of the present invention is shown.
[0046] Figure 2A MAP diagram of a hydrogen circulation pump in an embodiment of the present invention is shown.
[0047] Figure 3 A block diagram of a fuel cell anode pressure control device in an embodiment of the present invention is shown. DETAILED DESCRIPTION
[0048] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.
[0049] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0050] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.
[0051] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0052] According to the law of conservation of mass, the rate of change of hydrogen mass in the anode flow channel is equal to the hydrogen inlet flow minus the hydrogen outlet flow and the hydrogen reaction consumption. Among them, the hydrogen inlet flow includes the hydrogen flow from the hydrogen storage bottle entering the anode inlet through the proportional valve and the hydrogen flow from the hydrogen circulation pump circulating back to the anode inlet. Therefore, when the DV valve is opened, in order to maintain the anode pressure stable, the anode pressure needs to be appropriately compensated.
[0053] The present invention calculates the hydrogen pressure consumed inside the fuel cell stack, the gas pressure discharged by the DV valve and the hydrogen pressure circulated to the intake pipeline by the circulating pump during the DV valve opening time, and performs real-time compensation for the initial value of the anode pressure that controls the opening of the proportional valve, thereby reducing the fluctuation of the anode pressure when the exhaust valve (i.e., the DV valve) is opened and extending the life of the fuel cell.
[0054] Based on the above situation, the embodiment of the present invention provides a method for controlling the anode pressure of a fuel cell. Figure 1 As shown in the flowchart, the fuel cell anode pressure control method includes steps 101 to 105:
[0055] Step 101: When the DV valve is opened, the current density of the battery stack, the number of cells, the effective active area of the battery, the anode volume, the gas temperature of the anode side reaction, the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the gas temperature flowing into the DV valve, the pressure ratio of the hydrogen circulation pump, the speed of the hydrogen circulation pump and the gas temperature flowing into the hydrogen circulation pump are obtained;
[0056] In this embodiment, the number of cells, the effective active area of the cells, and the volume of the anode are some parameters of the fuel cell, which can be directly obtained. Other data, such as temperature, pressure, etc., can be collected and obtained through sensors.
[0057] The number of cells refers to the number of cells in the battery stack. The gas temperature of the anode side reaction refers to the temperature of the hydrogen and other mixed gases reacting at the anode.
[0058] Step 102: Calculate the hydrogen pressure consumed inside the stack according to the current density of the stack, the number of cells, the effective active area of the cell, the anode volume, and the gas temperature of the anode-side reaction;
[0059] Specifically, it is to calculate the hydrogen pressure consumed inside the fuel cell stack during the DV valve opening time. The hydrogen flow consumed by the reaction inside the fuel cell stack can be calculated first, and then the hydrogen pressure consumed inside the fuel cell stack can be further calculated. Specifically, it includes:
[0060] The hydrogen flow rate consumed by the reaction in the stack is calculated according to the current density of the stack, the number of cells, and the effective active area of the cell; the specific formula is:
[0061]
[0062] Among them, Mreact is the hydrogen flow consumed by the reaction in the battery stack, N is the number of battery cells, and M H2 is the molar mass of hydrogen, A act is the effective active area of the battery, F is the Faraday constant, i stack is the current density of the battery stack.
[0063] Then, the hydrogen pressure consumed in the stack is calculated according to the hydrogen flow rate consumed in the reaction in the stack, the gas temperature of the anode side reaction, the hydrogen gas constant, and the anode volume; the specific formula is:
[0064]
[0065] Where Preact is the hydrogen pressure consumed inside the stack, Mreact is the hydrogen flow consumed by the reaction inside the stack, R is the hydrogen gas constant, T1 is the gas temperature of the anode side reaction, V an is the anode volume, i stack is the current density of the battery stack, t0 is the opening time of the DV valve, t is the current time and t is less than the closing time of the DV valve.
[0066] Step 103: Calculate the hydrogen pressure discharged from the DV valve according to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the anode volume and the gas temperature flowing into the DV valve;
[0067] In this embodiment, the DV valve is simplified into a nozzle with a circular cross section, and the valve flow cross-sectional area refers to the cross-sectional area of the DV valve that allows flow at the current opening.
[0068] In this embodiment, assuming that the hydrogen-nitrogen ratio in the DV valve exhaust gas is k:1, the flow rate of hydrogen in the DV valve exhaust gas can be calculated first, and then the partial pressure of hydrogen in the DV valve exhaust gas, that is, the exhaust hydrogen pressure of the DV valve, can be further calculated. Specifically, it includes:
[0069] The flow rate of hydrogen in the gas discharged from the DV valve is calculated according to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, and the gas temperature flowing into the DV valve. The formula is as follows:
[0070]
[0071] Among them, M DV is the flow rate of hydrogen in the exhaust gas from the DV valve, C d is the valve flow coefficient, A t is the valve flow cross-sectional area, p DV,in is the gas pressure flowing into the DV valve, p DV,out is the gas pressure flowing out of the DV valve, T2 is the gas temperature flowing into the DV valve, γ is the adiabatic coefficient of the gas, and R is the hydrogen gas constant.
[0072] Then, the hydrogen pressure discharged from the DV valve is calculated according to the flow rate of hydrogen in the gas discharged from the DV valve, the temperature of the gas flowing into the DV valve, and the volume of the anode. The formula is as follows:
[0073]
[0074] Among them, P DVis the hydrogen pressure discharged from the DV valve, k is the hydrogen-nitrogen ratio in the gas discharged from the DV valve, T2 is the gas temperature flowing into the DV valve, R is the hydrogen gas constant, V an is the anode volume, MDV is the flow rate of hydrogen in the exhaust gas from the DV valve, t0 is the opening time of the DV valve, t is the current time and t is less than the closing time of the DV valve.
[0075] Step 104: Calculate the hydrogen feedback pressure fed back to the anode inlet from the hydrogen circulation pump according to the pressure ratio value of the hydrogen circulation pump, the rotation speed of the hydrogen circulation pump and the temperature of the gas flowing into the hydrogen circulation pump;
[0076] In this embodiment, it is assumed that the gas input into the anode inlet by the hydrogen circulation pump is all hydrogen. Figure 2 As shown, the speed of the hydrogen circulation pump of model DQ30H is set by the load current. Corresponding to different speeds and pressures, the corresponding outlet flow rate can be obtained from the preset MAP diagram of the hydrogen circulation pump.
[0077] During the DV valve opening time, the hydrogen pressure fed back by the hydrogen circulation pump is:
[0078]
[0079] Among them, P RCP is the hydrogen pressure fed back by the hydrogen circulation pump, P(t) is the pressure ratio of the hydrogen circulation pump, n RCP is the speed of the hydrogen circulation pump, MAP(P(t),n RCP ) is the flow rate value fed back to the hydrogen inlet by the hydrogen circulation pump.
[0080] Step 105: Perform real-time compensation on the pressure value of the control proportional valve according to the preset anode pressure initial value of the control proportional valve opening, the hydrogen pressure consumed inside the fuel cell stack, the hydrogen discharge pressure of the DV valve and the hydrogen feedback pressure.
[0081] In this embodiment, the proportional valve is a PPV valve of the hydrogen inlet system, which is located after the solenoid valve (equivalent to the switch for hydrogen entering the stack). The pressure of hydrogen entering the stack can be controlled by controlling the opening of the proportional valve (in the range of 0-100%). The difference from the DV valve is that the DV valve is located after the gas-water separator of the out-of-stack system and is used to discharge exhaust gas. The DV valve has only two states: open and closed, and the opening cannot be controlled.
[0082] In this embodiment, the initial value of the anode pressure for controlling the opening of the proportional valve can be set to P0. During the DV valve opening time, the compensation of the pressure value P for controlling the proportional valve can refer to the following correction formula:
[0083] P=P0+P react +P DV -P RCP
[0084] Among them, P RCP is the hydrogen pressure fed back by the hydrogen circulation pump, P DV is the hydrogen discharge pressure of the DV valve, Preact is the hydrogen consumption pressure inside the fuel cell stack, and P0 is the initial value of the anode pressure.
[0085] In addition, the control method of the proportional valve can be PID control or fuzzy PID control.
[0086] In summary, the embodiment of the present specification provides a method for controlling the anode pressure of a fuel cell. When the DV valve is opened, the current density of the fuel cell stack, the number of cells, the effective active area of the cell, the anode volume, the gas temperature of the anode side reaction, the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the gas temperature flowing into the DV valve, the pressure ratio of the hydrogen circulation pump, the speed of the hydrogen circulation pump and the gas temperature flowing into the hydrogen circulation pump are obtained; the internal consumption of hydrogen in the fuel cell stack is calculated according to the current density of the fuel cell stack, the number of cells, the effective active area of the cell, the anode volume and the gas temperature of the anode side reaction. The gas pressure; the hydrogen pressure discharged from the DV valve is calculated according to the cross-sectional area of the valve flow, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the anode volume and the gas temperature flowing into the DV valve; the hydrogen feedback pressure fed back to the anode inlet by the hydrogen circulation pump is calculated according to the pressure ratio of the hydrogen circulation pump, the speed of the hydrogen circulation pump and the gas temperature flowing into the hydrogen circulation pump; the pressure value of the control proportional valve is compensated in real time according to the preset anode pressure initial value of the control proportional valve opening, the hydrogen pressure consumed inside the fuel cell stack, the hydrogen pressure discharged from the DV valve and the hydrogen feedback pressure. The fluctuation of the anode pressure when the exhaust valve is opened can be reduced, and the life of the fuel cell can be extended.
[0087] Based on the same inventive concept, Figure 3 As shown, this embodiment provides a fuel cell anode pressure control device, comprising:
[0088] The acquisition module is used to obtain the current density of the battery stack, the number of cells, the effective active area of the battery, the anode volume, the gas temperature of the anode side reaction, the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the gas temperature flowing into the DV valve, the pressure ratio of the hydrogen circulation pump, the speed of the hydrogen circulation pump and the gas temperature flowing into the hydrogen circulation pump when the DV valve is opened;
[0089] A first calculation module is used to calculate the pressure of hydrogen consumed inside the battery stack according to the current density of the battery stack, the number of battery cells, the effective active area of the battery, the anode volume and the gas temperature of the anode side reaction;
[0090] A second calculation module is used to calculate the discharge hydrogen pressure of the DV valve according to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the anode volume and the gas temperature flowing into the DV valve;
[0091] A third calculation module is used to calculate the hydrogen feedback pressure fed back to the anode inlet by the hydrogen circulation pump according to the pressure ratio value of the hydrogen circulation pump, the rotation speed of the hydrogen circulation pump and the temperature of the gas flowing into the hydrogen circulation pump;
[0092] The compensation module is used to compensate the pressure value of the control proportional valve in real time according to the preset initial value of the anode pressure of the control proportional valve opening, the hydrogen pressure consumed inside the fuel cell stack, the exhaust hydrogen pressure of the DV valve and the hydrogen feedback pressure.
[0093] Optionally, the calculating the hydrogen pressure consumed inside the battery stack according to the current density of the battery stack, the number of battery cells, the effective active area of the battery, the anode volume and the gas temperature of the anode-side reaction includes:
[0094] Calculating the flow rate of hydrogen consumed by the reaction in the battery stack according to the current density of the battery stack, the number of battery cells, and the effective active area of the battery;
[0095] The pressure of hydrogen consumed in the fuel cell stack is calculated based on the hydrogen flow rate consumed in the reaction in the fuel cell stack, the gas temperature of the anode side reaction, the hydrogen gas constant, and the anode volume.
[0096] Optionally, the calculating the flow rate of hydrogen consumed by the reaction in the battery stack according to the current density of the battery stack, the number of battery cells, and the effective active area of the battery includes:
[0097] According to the current density of the battery stack, the number of battery cells, and the effective active area of the battery, the hydrogen flow rate consumed by the reaction in the battery stack is calculated by the following formula:
[0098]
[0099] Among them, Mreact is the hydrogen flow consumed by the reaction in the battery stack, N is the number of battery cells, and M H2 is the molar mass of hydrogen, A act is the effective active area of the battery, F is the Faraday constant, i stack is the current density of the battery stack.
[0100] Optionally, the calculating the pressure of hydrogen consumed in the fuel cell stack according to the hydrogen flow consumed in the reaction in the fuel cell stack, the gas temperature of the anode side reaction, the hydrogen gas constant, and the anode volume includes:
[0101] The hydrogen pressure consumed in the stack is calculated according to the hydrogen flow rate consumed in the reaction in the stack, the gas temperature of the anode side reaction, the hydrogen gas constant, and the anode volume by the following formula:
[0102]
[0103] Where Preact is the hydrogen pressure consumed inside the stack, Mreact is the hydrogen flow consumed by the reaction inside the stack, R is the hydrogen gas constant, T1 is the gas temperature of the anode side reaction, V an is the anode volume, t0 is the DV valve opening time, t is the current time and t is less than the DV valve closing time.
[0104] Optionally, the calculating the discharge hydrogen pressure of the DV valve according to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the anode volume and the gas temperature flowing into the DV valve comprises:
[0105] Calculate the flow rate of hydrogen in the gas discharged from the DV valve according to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, and the gas temperature flowing into the DV valve;
[0106] The hydrogen pressure discharged from the DV valve is calculated according to the flow rate of hydrogen in the gas discharged from the DV valve, the temperature of the gas flowing into the DV valve, and the volume of the anode.
[0107] Optionally, the calculating the flow rate of hydrogen in the gas discharged from the DV valve according to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, and the gas temperature flowing into the DV valve comprises:
[0108] According to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, and the gas temperature flowing into the DV valve, the flow rate of hydrogen in the gas discharged from the DV valve is calculated by the following formula:
[0109]
[0110] Among them, M DV is the flow rate of hydrogen in the exhaust gas from the DV valve, C d is the valve flow coefficient, A t is the valve flow cross-sectional area, p DV,in is the gas pressure flowing into the DV valve, p DV,out is the gas pressure flowing out of the DV valve, T2 is the gas temperature flowing into the DV valve, γ is the adiabatic coefficient of the gas, and R is the hydrogen gas constant.
[0111] Optionally, the calculating the hydrogen pressure discharged from the DV valve according to the flow rate of hydrogen in the gas discharged from the DV valve, the temperature of the gas flowing into the DV valve, and the volume of the anode includes:
[0112] According to the partial pressure of hydrogen in the gas discharged from the DV valve, the temperature of the gas flowing into the DV valve, and the volume of the anode, the hydrogen pressure discharged from the DV valve is calculated by the following formula:
[0113]
[0114] Among them, P DV is the hydrogen pressure discharged from the DV valve, k is the hydrogen-nitrogen ratio in the gas discharged from the DV valve, T2 is the gas temperature flowing into the DV valve, R is the hydrogen gas constant, V an is the anode volume, MDV is the flow rate of hydrogen in the exhaust gas from the DV valve, t0 is the opening time of the DV valve, t is the current time and t is less than the closing time of the DV valve.
[0115] In summary, the embodiment of the present specification provides a fuel cell anode pressure control device, when the DV valve is opened, obtains the current density of the fuel cell stack, the number of cells, the effective active area of the cell, the anode volume, the gas temperature of the anode side reaction, the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the gas temperature flowing into the DV valve, the pressure ratio of the hydrogen circulation pump, the speed of the hydrogen circulation pump and the gas temperature flowing into the hydrogen circulation pump; calculates the internal consumption of hydrogen in the fuel cell stack according to the current density of the fuel cell stack, the number of cells, the effective active area of the cell, the anode volume and the gas temperature of the anode side reaction. The gas pressure; the hydrogen pressure discharged from the DV valve is calculated according to the cross-sectional area of the valve flow, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the anode volume and the gas temperature flowing into the DV valve; the hydrogen feedback pressure fed back to the anode inlet by the hydrogen circulation pump is calculated according to the pressure ratio of the hydrogen circulation pump, the speed of the hydrogen circulation pump and the gas temperature flowing into the hydrogen circulation pump; the pressure value of the control proportional valve is compensated in real time according to the preset anode pressure initial value of the control proportional valve opening, the hydrogen pressure consumed inside the fuel cell stack, the hydrogen pressure discharged from the DV valve and the hydrogen feedback pressure. The fluctuation of the anode pressure when the exhaust valve is opened can be reduced, and the life of the fuel cell can be extended.
[0116] Those skilled in the art can clearly understand that, for the convenience and simplicity of description, the specific working process of the fuel cell anode pressure control device described above can refer to the corresponding process in the aforementioned method, and will not be elaborated here.
[0117] According to the third aspect of the present invention, a controller is provided, which includes a fuel cell anode pressure control device, a memory, a processor and a communication unit. The memory stores machine-readable instructions executable by the processor. When the controller is running, the processor and the memory communicate through a bus, the processor executes the machine-readable instructions, and executes the fuel cell anode pressure control method.
[0118] The memory, processor and communication unit are electrically connected to each other directly or indirectly to achieve signal transmission or interaction. For example, these elements can be electrically connected to each other through one or more communication buses or signal lines. The fuel cell anode pressure control device includes at least one software function module that can be stored in the memory in the form of software or firmware. The processor is used to execute the executable module stored in the memory (such as the software function module or computer program included in the fuel cell anode pressure control device).
[0119] Among them, the memory can be, but is not limited to, random access memory (Random Access Memory, RAM), read-only memory (Read On ly Memory, ROM), programmable read-only memory (Programmable Read-Only Memory, PROM), erasable programmable read-only memory (Erasable Programmable Read-Only Memory, EPROM), electrically erasable read-only memory (Electrical Erasable Programmable Read-Only Memory, EEPROM), etc.
[0120] In some embodiments, the processor is used to perform one or more functions described in this embodiment. In some embodiments, the processor may include one or more processing cores (eg, a single-core processor (S) or a multi-core processor (S)).
[0121] In this embodiment, the memory is used to store the program, and the processor is used to execute the program after receiving the execution instruction. The process definition method disclosed in any implementation of this embodiment can be applied to the processor, or implemented by the processor.
[0122] The communication unit is used to establish a communication connection between the controller and other devices through the network, and to send and receive data through the network.
[0123] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the controller described above can refer to the corresponding process in the aforementioned method, and will not be elaborated here.
[0124] According to a fourth aspect of the present invention, a vehicle is provided, comprising a vehicle body and a controller installed in the vehicle body, the controller being used to implement the above-mentioned fuel cell anode pressure control method, wherein the vehicle is a new energy vehicle with a fuel cell.
[0125] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the controller of the vehicle described above can refer to the corresponding process in the aforementioned method, and will not be elaborated here.
[0126] The above are only various embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.
Claims
1. A method for controlling anode pressure of a fuel cell, characterized in that: include: When the DV valve is open, obtain the current density of the battery stack, the number of cells, the effective active area of the battery, the anode volume, the gas temperature of the anode side reaction, the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the gas temperature flowing into the DV valve, the pressure ratio of the hydrogen circulation pump, the speed of the hydrogen circulation pump and the gas temperature flowing into the hydrogen circulation pump; Calculating the hydrogen pressure consumed inside the stack according to the current density of the stack, the number of cells, the effective active area of the cell, the anode volume and the gas temperature of the anode-side reaction; Calculate the hydrogen pressure discharged from the DV valve according to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the anode volume and the gas temperature flowing into the DV valve; Calculating the hydrogen feedback pressure fed back to the anode inlet by the hydrogen circulation pump according to the pressure ratio value of the hydrogen circulation pump, the rotation speed of the hydrogen circulation pump and the temperature of the gas flowing into the hydrogen circulation pump; The pressure value of the control proportional valve is compensated in real time according to the preset initial value of the anode pressure of the control proportional valve opening, the hydrogen pressure consumed inside the fuel cell stack, the exhaust hydrogen pressure of the DV valve and the hydrogen feedback pressure.
2. The method according to claim 1, characterized in that The method of calculating the hydrogen pressure consumed inside the battery stack according to the current density of the battery stack, the number of battery cells, the effective active area of the battery, the anode volume and the gas temperature of the anode side reaction includes: Calculating the flow rate of hydrogen consumed by the reaction in the battery stack according to the current density of the battery stack, the number of battery cells, and the effective active area of the battery; The pressure of hydrogen consumed in the fuel cell stack is calculated based on the hydrogen flow rate consumed in the reaction in the fuel cell stack, the gas temperature of the anode side reaction, the hydrogen gas constant, and the anode volume.
3. The method according to claim 2, characterized in that The method of calculating the flow rate of hydrogen consumed by the reaction in the battery stack according to the current density of the battery stack, the number of battery cells, and the effective active area of the battery comprises: According to the current density of the battery stack, the number of battery cells, and the effective active area of the battery, the hydrogen flow rate consumed by the reaction in the battery stack is calculated by the following formula: Where Mreact is the hydrogen flow consumed by the reaction in the battery stack, N is the number of battery cells, is the molar mass of hydrogen, A act is the effective active area of the battery, F is the Faraday constant, i stack is the current density of the battery stack.
4. The method according to claim 2, characterized in that: The method of calculating the pressure of hydrogen consumed in the fuel cell stack according to the hydrogen flow rate consumed in the reaction in the fuel cell stack, the gas temperature of the anode side reaction, the hydrogen gas constant, and the anode volume includes: The hydrogen pressure consumed in the stack is calculated according to the hydrogen flow rate consumed in the reaction in the stack, the gas temperature of the anode side reaction, the hydrogen gas constant, and the anode volume by the following formula: Where Preact is the hydrogen pressure consumed inside the stack, Mreact is the hydrogen flow consumed by the reaction inside the stack, R is the hydrogen gas constant, T1 is the gas temperature of the anode side reaction, V an is the anode volume, i stack is the current density of the battery stack, t0 is the opening time of the DV valve, t is the current time and t is less than the closing time of the DV valve.
5. The method according to claim 1, characterized in that The method of calculating the hydrogen pressure discharged from the DV valve according to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the anode volume and the gas temperature flowing into the DV valve comprises: Calculate the flow rate of hydrogen in the gas discharged from the DV valve according to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, and the gas temperature flowing into the DV valve; The hydrogen pressure discharged from the DV valve is calculated according to the flow rate of hydrogen in the gas discharged from the DV valve, the temperature of the gas flowing into the DV valve, and the volume of the anode.
6. The method according to claim 5, characterized in that The method of calculating the flow rate of hydrogen in the gas discharged from the DV valve according to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, and the gas temperature flowing into the DV valve comprises: According to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, and the gas temperature flowing into the DV valve, the flow rate of hydrogen in the gas discharged from the DV valve is calculated by the following formula: Among them, M DV is the flow rate of hydrogen in the exhaust gas from the DV valve, C d is the valve flow coefficient, A t is the valve flow cross-sectional area, p DV,in is the gas pressure flowing into the DV valve, p DV,out is the gas pressure flowing out of the DV valve, T2 is the gas temperature flowing into the DV valve, γ is the adiabatic coefficient of the gas, and R is the hydrogen gas constant.
7. The method according to claim 5, characterized in that The method of calculating the hydrogen pressure discharged from the DV valve according to the flow rate of hydrogen in the gas discharged from the DV valve, the temperature of the gas flowing into the DV valve, and the volume of the anode comprises: According to the partial pressure of hydrogen in the gas discharged from the DV valve, the temperature of the gas flowing into the DV valve, and the volume of the anode, the hydrogen pressure discharged from the DV valve is calculated by the following formula: Among them, P DV is the hydrogen pressure discharged from the DV valve, k is the hydrogen-nitrogen ratio in the gas discharged from the DV valve, T2 is the gas temperature flowing into the DV valve, R is the hydrogen gas constant, V an is the anode volume, MDV is the flow rate of hydrogen in the exhaust gas from the DV valve, t0 is the opening time of the DV valve, t is the current time and t is less than the closing time of the DV valve.
8. A fuel cell anode pressure control device, characterized in that: include: The acquisition module is used to obtain the current density of the battery stack, the number of cells, the effective active area of the battery, the anode volume, the gas temperature of the anode side reaction, the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the gas temperature flowing into the DV valve, the pressure ratio of the hydrogen circulation pump, the speed of the hydrogen circulation pump and the gas temperature flowing into the hydrogen circulation pump when the DV valve is opened; A first calculation module is used to calculate the pressure of hydrogen consumed inside the battery stack according to the current density of the battery stack, the number of battery cells, the effective active area of the battery, the anode volume and the gas temperature of the anode side reaction; A second calculation module is used to calculate the discharge hydrogen pressure of the DV valve according to the valve flow cross-sectional area, the gas pressure flowing into the DV valve, the gas pressure flowing out of the DV valve, the anode volume and the gas temperature flowing into the DV valve; A third calculation module is used to calculate the hydrogen feedback pressure fed back to the anode inlet by the hydrogen circulation pump according to the pressure ratio value of the hydrogen circulation pump, the rotation speed of the hydrogen circulation pump and the temperature of the gas flowing into the hydrogen circulation pump; The compensation module is used to compensate the pressure value of the control proportional valve in real time according to the preset initial value of the anode pressure of the control proportional valve opening, the hydrogen pressure consumed inside the fuel cell stack, the exhaust hydrogen pressure of the DV valve and the hydrogen feedback pressure.
9. A controller, characterized in that: The controller includes: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the fuel cell anode pressure control method described in any one of claims 1 to 7 is implemented.
10. A vehicle, characterized in that: The vehicle comprises a vehicle body and a controller installed in the vehicle body, wherein the controller executes the fuel cell anode pressure control method as described in any one of claims 1-7.