Control method and equipment for air system in cold start process of fuel cell

Abstract

The invention relates to a control method and equipment for an air system in the cold start process of a fuel cell, and relates to the field of fuel cells. In the cold start process of the fuel cell, the opening degree of the back pressure valve is set to be a fixed value, closed-loop control over the rotating speed of the air compressor and open-loop control over the opening degree of the bypass valve are conducted, and therefore the air flow control accuracy and stability of the fuel cell system are greatly improved. Besides, the starting temperature which is calculated only in the power-on initialization state and is not updated any more in the subsequent starting and running process is set, the target air pressure is corrected and calculated through the starting temperature to obtain a target air pressure correction value, and then the opening degree of the back pressure valve and the opening degree of the bypass valve are compensated and adjusted according to the correction value. Therefore, the system can reach the required optimal target air pressure during cold start in different low-temperature environments, so that the start adaptability and reliability of the fuel cell in different low-temperature environments are enhanced.

Description

Technical Field

[0001] The present application relates to the field of fuel cell technology, and in particular to a control method and device for an air system during a cold start process of a fuel cell. Background Art

[0002] A hydrogen fuel cell is a power generation device that converts chemical energy into electrical energy through an electrochemical reaction. It has the advantages of high efficiency and low pollution, and has good application prospects in the fields of automobiles, off-road, and fixed power generation. In recent years, fuel cell technology has developed rapidly, but the R&D cost, cold start performance, and reliability of fuel cell systems are still bottlenecks that hinder its commercialization. Reasonable fuel cell control strategies can not only maintain the stable operation of fuel cells and improve dynamic response performance, but also help improve the output efficiency of fuel cells.

[0003] In the prior art, there are three main methods for controlling the air system during the cold start of a fuel cell:

[0004] The first is to use a fixed strategy in which the air compressor runs at the lowest speed and the bypass valve and back pressure valve are fully open. However, this method uses a purely fixed open-loop control and cannot adjust the air flow in a closed loop to accurately control the starvation heating power, so its adaptability is very poor.

[0005] The second is the strategy proposed in patent CN117059146A that adopts the strategy of fully opening the back pressure valve and performing segmented closed-loop control of the air compressor speed and the bypass valve opening according to the actual current size. However, due to the fully opening of the back pressure valve, the air pressure entering the stack cannot reach a high level, which is not conducive to starting, and the start-up adaptability in different low-temperature environments is poor. In addition, when the air compressor speed and the bypass valve opening are closed-loop controlled in segments according to the actual current size, there is a switch in the closed-loop regulation object in the middle, which is easy to cause voltage fluctuations.

[0006] The third strategy is to use the closed-loop adjustment method of the air compressor and back-pressure valve to control the air flow and pressure; however, due to the fact that the air flow of the fuel cell system is sensitive to the change in the opening of the back-pressure valve, even if the back-pressure valve changes in the opening step with a control accuracy during closed-loop control, the air flow will still fluctuate greatly, and its control accuracy and stability are poor.

[0007] Therefore, it is necessary to make improvements based on the above method, which can not only meet the requirements of air flow control accuracy and continuous stability, but also ensure that the air pressure entering the pile can reach a level that is more conducive to startup under different low-temperature environments. Summary of the invention

[0008] The purpose of the present application is to provide a control method, device and equipment for the air system of a fuel cell cold start process to solve the problems existing in the above-mentioned prior art.

[0009] To achieve the above purpose, the technical solution adopted in this application is:

[0010] In a first aspect, the present application provides a method for controlling an air system during a cold start of a fuel cell, the method being applied to a control device for an air system during a cold start of a fuel cell, the device comprising a controller, a first air flow meter, an air compressor, a fuel cell stack, a back pressure valve, a bypass valve, a second air flow meter, a stack inlet coolant temperature sensor, a stack outlet coolant temperature sensor, and a pressure sensor;

[0011] The method comprises:

[0012] Determining the air flow rate entering the stack, the air pressure entering the stack, the target air flow rate, the target air pressure, the target air pressure correction value, the basic opening value of the back pressure valve, and the basic opening value of the bypass valve;

[0013] Based on the target air flow rate and the target air pressure, determine the speed feedforward value of the air compressor; according to the target air flow rate and the inlet air flow rate, determine the speed closed-loop adjustment value of the air compressor; by summing the speed feedforward value of the air compressor and the speed closed-loop adjustment value of the air compressor, determine the final speed value of the air compressor;

[0014] Based on the target air pressure correction value, determine the opening correction value of the back pressure valve; by summing the opening base value of the back pressure valve and the opening correction value of the back pressure valve, determine the final opening value of the back pressure valve;

[0015] Based on the target air flow rate and the target air pressure correction value, determine the opening correction value of the bypass valve; by summing the opening base value of the bypass valve and the opening correction value of the bypass valve, determine the final opening value of the bypass valve;

[0016] The air compressor, the back pressure valve and the bypass valve are regulated according to the final value of the air compressor speed, the final value of the opening of the back pressure valve and the final value of the opening of the bypass valve, respectively, so that the inlet air flow rate and the inlet air pressure are stabilized at target values.

[0017] In a possible implementation, the first air flow meter is installed on a pipeline between the air filter and the air compressor, and is used to measure the total air flow entering the air compressor;

[0018] The second air flow meter is installed on the rear end pipeline of the bypass valve and is used to measure the air bypass flow rate;

[0019] The inlet coolant temperature sensor is installed at the coolant inlet of the fuel cell stack and is used to measure the inlet coolant temperature;

[0020] The outgoing coolant temperature sensor is installed at the coolant outlet of the stack and is used to measure the outgoing coolant temperature;

[0021] The pressure sensor is installed at the air inlet of the fuel cell stack and is used to measure the air pressure entering the stack;

[0022] The controller is used to regulate the air compressor, the back pressure valve and the bypass valve according to the collected sensor signals and flow meter signals, so that the inlet air flow rate and the inlet air pressure are stabilized at target values.

[0023] In a possible implementation, determining the air flow rate of the stack includes:

[0024] Obtaining a total air flow and an air bypass flow measured by the first air flow meter and the second air flow meter;

[0025] Determine the stack air flow rate by subtracting the total air flow rate from the air bypass flow rate;

[0026] The step of determining the air pressure for entering the stack comprises:

[0027] The stack air pressure measured by the pressure sensor is obtained.

[0028] In a possible implementation, determining the target air flow rate includes:

[0029] Determine the target air flow rate by multiplying the theoretical required air flow rate by the target excess air coefficient;

[0030] Determining the target air pressure correction value includes:

[0031] Acquiring the inlet coolant temperature and the outlet coolant temperature measured by the inlet coolant temperature sensor and the outlet coolant temperature sensor;

[0032] Based on the inlet coolant temperature and the outlet coolant temperature, a start-up temperature is initialized in combination with a power-on switch signal to determine a start-up temperature;

[0033] determining the target air pressure correction value according to the starting temperature;

[0034] Determining the target air pressure includes:

[0035] According to the target current, determine the target air pressure base value;

[0036] The target air pressure is determined by summing the target air pressure correction value and the target air pressure base value.

[0037] In a possible implementation, the starting temperature is initialized based on the inlet coolant temperature and the outlet coolant temperature in combination with a power-on switch signal to determine the starting temperature, including:

[0038] In response to the controller being powered on, the power-on switch signal is 1, the controller enters a power-on initialization state, and the power-on initialization state flag is set from 0 to 1;

[0039] Taking the smaller one of the inlet coolant temperature and the outlet coolant temperature as the starting reference temperature;

[0040] In response to the controller detecting that the power-on initialization state flag is 1, the startup reference temperature at that moment is recorded as the startup temperature, that is, the startup temperature is only calculated and kept fixed in the power-on initialization state, and is no longer updated during subsequent startup and operation processes.

[0041] In a possible implementation, determining the opening base value of the back pressure valve includes:

[0042] Determine the basic opening value of the back pressure valve by calibrating the basic opening amount of the back pressure valve;

[0043] Determining the basic value of the opening of the bypass valve includes:

[0044] Based on the target air flow rate, a basic opening value of the bypass valve is determined.

[0045] In a possible implementation, the basic opening calibration amount of the back pressure valve is an opening value between fully open and fully closed.

[0046] In a possible implementation, determining a closed-loop adjustment value of the speed of the air compressor according to the target air flow rate and the inlet air flow rate includes:

[0047] determining an air flow difference according to the target air flow and the stack inlet air flow;

[0048] A PID control calculation is performed based on the air flow difference to determine a closed-loop adjustment value of the speed of the air compressor.

[0049] In a possible implementation, the controller includes:

[0050] a determination module, used to determine the air flow rate of the stack, the air pressure of the stack, the target air flow rate, the target air pressure, the target air pressure correction value, the basic opening value of the back pressure valve and the basic opening value of the bypass valve;

[0051] The determination module is further configured to determine a speed feedforward value of the air compressor based on the target air flow rate and the target air pressure; determine a speed closed-loop adjustment value of the air compressor according to the target air flow rate and the stack air flow rate; and determine a final speed value of the air compressor by summing the speed feedforward value of the air compressor and the speed closed-loop adjustment value of the air compressor;

[0052] The determination module is further used to determine the opening correction value of the back pressure valve based on the target air pressure correction value; and to determine the final opening value of the back pressure valve by summing the opening base value of the back pressure valve and the opening correction value of the back pressure valve;

[0053] The determination module is further configured to determine an opening correction value of the bypass valve based on the target air flow rate and the target air pressure correction value; and determine a final opening value of the bypass valve by summing the opening base value of the bypass valve and the opening correction value of the bypass valve;

[0054] The control module is used to control the air compressor, the back pressure valve and the bypass valve according to the final value of the speed of the air compressor, the final value of the opening of the back pressure valve and the final value of the opening of the bypass valve, so as to stabilize the inlet air flow and the inlet air pressure at the target value.

[0055] In a second aspect, the present application provides a computer device, comprising a processor and a memory, wherein the memory stores at least one instruction, at least one program, a code set or an instruction set, and the processor can load and execute at least one instruction, at least one program, a code set or an instruction set to implement the control method of the air system of the fuel cell cold start process provided above.

[0056] In a third aspect, the present application provides a computer-readable storage medium, which stores at least one instruction, at least one program, code set or instruction set. The processor can load and execute at least one instruction, at least one program, code set or instruction set to implement the control method of the air system of the fuel cell cold start process provided above.

[0057] In a fourth aspect, the present application provides a computer program product or a computer program, the computer program product or the computer program including computer program instructions, the computer program instructions being stored in a computer-readable storage medium. The processor reads the computer instructions from the computer-readable storage medium and executes the computer instructions, so that the computer device executes the control method of the air system of the fuel cell cold start process provided above.

[0058] The beneficial effects of the technical solution provided by this application include at least:

[0059] This application aims at the characteristic that the air flow of the fuel cell system is more sensitive to the change of the back pressure valve opening, and at the same time, takes advantage of the high precision of the air compressor speed control and the fine control of the air flow. During the cold start of the fuel cell, by setting the back pressure valve opening to a fixed value, and then by closed-loop control of the air compressor speed and open-loop control of the bypass valve opening, the air flow control accuracy and stability of the fuel cell system are greatly improved, thereby meeting the requirements for accurate control of the air flow when the fuel cell system adopts the oxygen starvation route for low-temperature start. In addition, by setting a start temperature that is only calculated in the power-on initialization state and is no longer updated during the subsequent start and operation process, and using the start temperature to correct the target air pressure to obtain the target air pressure correction value, and then according to the correction value, the back pressure valve opening and the bypass valve opening are compensated and adjusted to ensure that the system can reach the required optimal target air pressure when cold starting in different low-temperature environments, thereby enhancing the start-up adaptability and reliability of the fuel cell in different low-temperature environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] The accompanying drawings are used to provide a further understanding 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 present application and do not constitute a limitation of the present application. In the accompanying drawings:

[0061] Figure 1 A schematic structural diagram of a control device for an air system during a cold start of a fuel cell provided by an exemplary embodiment of the present application is shown.

[0062] Figure 2 A method for controlling an air system during a cold start of a fuel cell provided by an exemplary embodiment of the present application is shown.

[0063] Figure 3 and Figure 4 A flow chart and a logic block diagram are respectively shown of another method for controlling an air system during a cold start of a fuel cell provided by an exemplary embodiment of the present application.

[0064] Figure 5 An air compressor speed feedforward MAP of another method for controlling an air system during a cold start of a fuel cell provided by an exemplary embodiment of the present application is shown.

[0065] Figure 6 A bypass valve opening correction MAP of another fuel cell cold start process air system control method provided by an exemplary embodiment of the present application is shown.

[0066] Figure 7 A structural block diagram of a controller of a control device for an air system of a fuel cell cold start process provided by an exemplary embodiment of the present application is shown.

[0067] Figure 8 A schematic diagram of the structure of a computer device for executing a method for controlling an air system during a cold start process of a fuel cell provided by an exemplary embodiment of the present application is shown. DETAILED DESCRIPTION

[0068] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0069] The present application is further described below in conjunction with the accompanying drawings and embodiments.

[0070] Figure 1 A schematic diagram of the structure of a control device for an air system of a fuel cell cold start process provided by an exemplary embodiment of the present application is shown, the device comprising: a controller 1, a first air flow meter 2, an air compressor 3, a fuel cell stack 4, a back pressure valve 5, a bypass valve 6, a second air flow meter 7, a stack inlet coolant temperature sensor 8, a stack outlet coolant temperature sensor 9, and a pressure sensor 10; wherein the first air flow meter 2 is installed on the pipeline between the air filter and the air compressor 3, and is used to measure the total air flow entering the air compressor 3; the second air flow meter 7 is installed at the rear end of the bypass valve 6 The pipeline is used to measure the air bypass flow rate; the inlet coolant temperature sensor 8 is installed at the coolant inlet of the fuel cell 4 to measure the inlet coolant temperature; the outlet coolant temperature sensor 9 is installed at the coolant outlet of the fuel cell 4 to measure the outlet coolant temperature; the pressure sensor 10 is installed at the air inlet of the fuel cell 4 to measure the inlet air pressure; the controller 1 is used to regulate the air compressor 3, the back pressure valve 5 and the bypass valve 6 according to all the above-mentioned sensor signals and flow meter signals collected, so that the inlet air flow and the inlet air pressure are stabilized at the target value.

[0071] In the embodiment of the present application, air flows into the air filter and is filtered, and then enters the air compressor 3 through the first air flow meter 2. The air compressed by the air compressor 3 enters the fuel cell stack 4 through the intercooler (not shown in the figure) in the first route, and the exhaust gas of the fuel cell stack is discharged through the back pressure valve 5; the air compressed by the air compressor 3 passes through the bypass valve 6 and then flows through the second air flow meter 7, and is finally mixed with the exhaust gas discharged by the back pressure valve 6.

[0072] Figure 2 A control method for an air system of a fuel cell cold start process provided by an exemplary embodiment of the present application is shown, and the method is applied to a computer device, and the method includes:

[0073] Step 201 , determining the air flow rate entering the stack, the air pressure entering the stack, the target air flow rate, the target air pressure, the target air pressure correction value, the basic opening value of the back pressure valve, and the basic opening value of the bypass valve.

[0074] In the embodiments of the present application, the back pressure valve and the bypass valve are important components for controlling the pressure and flow in the fluid system, especially in the fuel cell system, where they are crucial to ensure the stable operation and performance optimization of the system.

[0075] Step 202, based on the target air flow and the target air pressure, determine the speed feedforward value of the air compressor; according to the target air flow and the inlet air flow, determine the speed closed-loop adjustment value of the air compressor; by summing the speed feedforward value of the air compressor and the speed closed-loop adjustment value of the air compressor, determine the final value of the speed of the air compressor.

[0076] Specifically, based on the target air flow and the target air pressure, the air compressor speed feedforward MAP (map chart) is checked to determine the air compressor speed feedforward value.

[0077] Step 203, based on the target air pressure correction value, determine the opening correction value of the back pressure valve; and determine the final opening value of the back pressure valve by summing the opening base value of the back pressure valve and the opening correction value of the back pressure valve.

[0078] Specifically, based on the target air pressure correction value, the back pressure valve opening correction curve is checked to determine the back pressure valve opening correction value.

[0079] Step 204 , determining an opening correction value of the bypass valve based on the target air flow and the target air pressure correction value; and determining a final opening value of the bypass valve by summing the opening base value of the bypass valve and the opening correction value of the bypass valve.

[0080] In this step, based on the target air flow rate and the target air pressure correction value, the bypass valve opening correction MAP (map) is checked to determine the bypass valve opening correction value.

[0081] Step 205, regulating the air compressor, the back pressure valve and the bypass valve according to the final value of the air compressor speed, the final value of the back pressure valve opening and the final value of the bypass valve opening, so that the air flow rate and the air pressure entering the stack are stabilized at the target value.

[0082] In the above steps 202 to 205, during the cold start process of the fuel cell, the back pressure valve opening is set to a fixed value, and then the air compressor speed is closed-loop controlled and the bypass valve opening is open-loop controlled, so that the air flow control accuracy and stability of the fuel cell system are greatly improved, thereby meeting the fuel cell system's precise control requirements for air flow when the fuel cell system adopts the oxygen starvation route for low-temperature start-up.

[0083] Figure 3 and Figure 4 A flow chart and a logic block diagram are respectively shown of another method for controlling an air system of a fuel cell cold start process provided by an exemplary embodiment of the present application. The method is applied to a computer device, and the method includes:

[0084] Step 301, obtaining the total air flow and the air bypass flow measured by the first air flow meter and the second air flow meter, and determining the air flow entering the stack by subtracting the total air flow from the air bypass flow.

[0085] It is worth mentioning that before this step, the controller is also powered on and initialized.

[0086] Step 302: Obtain the air pressure entering the stack measured by the pressure sensor.

[0087] Step 303: Determine the target air flow rate by multiplying the theoretical required air flow rate by the target excess air coefficient.

[0088] In the embodiment of the present application, the theoretical required air flow rate, that is, the air flow rate required for the fuel cell reaction when the equivalent ratio is 1, is calculated as follows:

[0089] Q air =(124.14*N cell *I tg ) / F;

[0090] Among them, Q air is the theoretical required air flow; N cell is the total number of cells in the battery stack; I tg is the target current of the battery stack; F is the Faraday constant, which is generally 96485c / mol.

[0091] In the embodiments of the present application, the excess air coefficient, usually represented by the symbol λ, is a measure of the ratio of the amount of air actually provided during the fuel combustion or chemical reaction to the minimum amount of air theoretically required for complete combustion or complete reaction, that is, excess air coefficient = actual amount of air supplied / theoretically amount of air required for complete combustion or reaction.

[0092] Step 304, obtaining the inlet coolant temperature and the outlet coolant temperature measured by the inlet coolant temperature sensor and the outlet coolant temperature sensor; initializing the start temperature based on the inlet coolant temperature and the outlet coolant temperature in combination with the power-on switch signal to determine the start temperature; and determining the target air pressure correction value according to the start temperature.

[0093] In detail, based on the inlet coolant temperature and outlet coolant temperature, the startup temperature is initialized in combination with the power-on switch signal to determine the startup temperature, including: in response to the controller being powered on, the power-on switch signal is 1, the controller enters the power-on initialization state, and the power-on initialization state flag is set from 0 to 1; the smaller of the inlet coolant temperature and the outlet coolant temperature is taken as the startup reference temperature; in response to the controller detecting that the power-on initialization state flag is 1, the startup reference temperature at that moment is recorded as the startup temperature, that is, the startup temperature is only calculated and kept fixed in the power-on initialization state, and is no longer updated in the subsequent startup and operation process. This setting allows the back pressure valve opening to remain fixed during the startup process when the system is cold started at different temperatures, thereby ensuring the stability of the air flow.

[0094] Furthermore, according to the starting temperature, the target air pressure correction curve is checked to determine the target air pressure correction value.

[0095] Step 305, determining a target air pressure base value according to the target current; and determining the target air pressure by summing the target air pressure correction value and the target air pressure base value.

[0096] Furthermore, according to the target current, the basic target air pressure curve is checked to determine the basic value of the target air pressure.

[0097] In the embodiment of the present application, the target current is the target working current value set during the fuel cell startup process, which is calculated based on the required power generation and heating power. An example of the target air pressure base value is shown in the following table, in which the X-axis is the target current, and the value corresponding to the Z-axis is the target air pressure base value obtained by querying the two-dimensional curve through the target current:

[0098] X-axis 10 30 60 90 120 150 180 210 240 270 300 330 360 390 450 Z-axis 40 45 50 55 60 65 70 75 80 85 90 95 100 105 115

[0099] Through this step 305, the fuel cell can correct the target air pressure according to the current startup temperature to obtain the optimal target air pressure required for startup in different temperature environments, so as to enhance the startup adaptability and reliability of the fuel cell in different temperature environments.

[0100] Step 306, determining the basic opening value of the back pressure valve through the basic opening calibration value of the back pressure valve.

[0101] It is worth mentioning that the basic opening calibration of the back pressure valve is an opening value between fully open and fully closed, preferably in the range of 50% to 60%, so as to ensure that the air pressure entering the stack can reach a relatively high level and facilitate cold start.

[0102] Step 307: Determine a basic opening value of the bypass valve based on the target air flow rate.

[0103] In this step, based on the target air flow, the basic bypass valve opening curve is checked to determine the basic opening value of the bypass valve.

[0104] Step 308, based on the target air flow and the target air pressure, determine the speed feedforward value of the air compressor; determine the air flow difference according to the target air flow and the inlet air flow; perform PID calculation based on the air flow difference to determine the speed closed-loop adjustment value of the air compressor; determine the final value of the air compressor speed by summing the speed feedforward value of the air compressor and the speed closed-loop adjustment value of the air compressor.

[0105] In the present application, PID (Proportional-Integral-Differential Control) is a feedback control mechanism widely used in the field of industrial automation. It controls the output of the system by adjusting three parameters - proportional (P), integral (I) and differential (D) to achieve the desired target value. The PID controller can effectively handle the steady-state error, response speed and stability of the dynamic system.

[0106] Specifically, based on the target air flow and target air pressure, check the compressor speed feedforward MAP (map spectrum) to determine the compressor speed feedforward value. Figure 5 , the X-axis is the target air flow, the Y-axis is the target air pressure, and the corresponding values ​​in the figure are the speed feedforward values ​​of the air compressor obtained by querying the three-dimensional MAP (map) by the target air flow and target air pressure.

[0107] Step 309, determining the opening correction value of the back pressure valve based on the target air pressure correction value; and determining the final opening value of the back pressure valve by summing the opening base value of the back pressure valve and the opening correction value of the back pressure valve.

[0108] Specifically, based on the target air pressure correction value, the back pressure valve opening correction curve is checked to determine the back pressure valve opening correction value. The back pressure valve opening correction curve has the characteristic that the back pressure valve opening correction value gradually decreases with the increase of the target air pressure correction value and is a negative value, so as to ensure that the fuel cell can reach a higher air pressure level at a lower starting temperature and better facilitate cold starting.

[0109] Step 310, determining the bypass valve opening correction value based on the target air flow and the target air pressure correction value; and determining the bypass valve opening final value by summing the bypass valve opening base value and the bypass valve opening correction value.

[0110] In this step, based on the target air flow and the target air pressure correction value, the bypass valve opening correction MAP (map) is checked to determine the bypass valve opening correction value. Figure 6, the X-axis is the target air flow, the Y-axis is the target air pressure correction value, and the corresponding value in the figure is the bypass valve opening correction value obtained by querying the three-dimensional MAP (map chart) by the target air flow and the target air pressure correction value.

[0111] Step 311, the air compressor, the back pressure valve and the bypass valve are regulated according to the final value of the air compressor speed, the final value of the back pressure valve opening and the final value of the bypass valve opening, so that the air flow rate and the air pressure entering the stack are stabilized at the target value.

[0112] It should be noted that the air compressor speed feedforward value, back pressure valve basic opening calibration value, back pressure valve opening correction curve, basic bypass valve opening curve, and bypass valve opening correction MAP (spectrum diagram) in the above steps are all obtained through bench testing of the fuel cell system. By setting the above parameters, the actual air flow and air pressure reach the target values.

[0113] Figure 7 A structural block diagram of a controller of a control device for a cold start process air system of a fuel cell provided by an exemplary embodiment of the present application is shown, and the controller includes:

[0114] A determination module 702 is used to determine the air flow rate of the stack, the air pressure of the stack, the target air flow rate, the target air pressure, the target air pressure correction value, the basic value of the opening of the back pressure valve and the basic value of the opening of the bypass valve;

[0115] The determination module 702 is further used to determine the speed feedforward value of the air compressor based on the target air flow rate and the target air pressure; determine the speed closed-loop adjustment value of the air compressor according to the target air flow rate and the air flow rate of the stack; and determine the final speed value of the air compressor by summing the speed feedforward value of the air compressor and the speed closed-loop adjustment value of the air compressor;

[0116] The determination module 702 is further used to determine the opening correction value of the back pressure valve based on the target air pressure correction value; and to determine the final opening value of the back pressure valve by summing the opening base value of the back pressure valve and the opening correction value of the back pressure valve;

[0117] The determination module 702 is further used to determine the opening correction value of the bypass valve based on the target air flow and the target air pressure correction value; and to determine the final opening value of the bypass valve by summing the opening base value of the bypass valve and the opening correction value of the bypass valve;

[0118] The control module 703 is used to control the air compressor, the back pressure valve and the bypass valve according to the final value of the air compressor speed, the final value of the back pressure valve opening and the final value of the bypass valve opening, so as to stabilize the air flow and the air pressure entering the stack at the target value.

[0119] Furthermore, the device also includes:

[0120] An acquisition module 701 is used to acquire the total air flow and the air bypass flow measured by the first air flow meter and the second air flow meter;

[0121] The determination module 702 is further configured to determine the stack air flow rate by subtracting the total air flow rate from the air bypass flow rate.

[0122] The acquisition module 701 is also used to obtain the air pressure of the stack measured by the pressure sensor;

[0123] The determination module 702 is further used to determine the target air flow rate by multiplying the theoretical required air flow rate by the target excess air coefficient;

[0124] The acquisition module 701 is further used to acquire the inlet coolant temperature and the outlet coolant temperature measured by the inlet coolant temperature sensor and the outlet coolant temperature sensor;

[0125] The determination module 702 is further used to initialize the startup temperature based on the inlet coolant temperature and the outlet coolant temperature in combination with the power-on switch signal to determine the startup temperature;

[0126] The determination module 702 is further used to determine a target air pressure correction value according to the start-up temperature;

[0127] The determination module 702 is further used to determine a target air pressure base value according to the target current;

[0128] The determination module 702 is further used to determine the target air pressure by summing the target air pressure correction value and the target air pressure base value;

[0129] The determination module 702 is further used to determine the basic opening value of the back pressure valve through the basic opening calibration amount of the back pressure valve;

[0130] The determination module 702 is further used to determine a basic opening value of the bypass valve based on the target air flow rate;

[0131] The determination module 702 is further used to determine the air flow difference according to the target air flow and the air flow entering the stack;

[0132] The determination module 702 is further used to perform PID calculation based on the air flow difference to determine the speed closed-loop adjustment value of the air compressor.

[0133] In some embodiments, the basic opening calibration amount of the back pressure valve is an opening value between fully open and fully closed.

[0134] In some embodiments, based on the inlet coolant temperature and the outlet coolant temperature, the startup temperature is initialized in combination with the power-on switch signal to determine the startup temperature, including: in response to the controller being powered on, the power-on switch signal is 1, the controller enters the power-on initialization state, and the power-on initialization state flag is set from 0 to 1; the smaller of the inlet coolant temperature and the outlet coolant temperature is taken as the startup reference temperature; in response to the controller detecting that the power-on initialization state flag is 1, the startup reference temperature at that moment is recorded as the startup temperature, that is, the startup temperature is only calculated and kept fixed in the power-on initialization state, and is no longer updated during subsequent startup and operation processes.

[0135] It should be noted that the control device of the air system of the fuel cell cold start process provided in the above embodiment is only illustrated by the division of the above functional modules. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the equipment can be divided into different functional modules to complete all or part of the functions described above.

[0136] Figure 8 A schematic diagram of the structure of a computer device for executing a control method for an air system during a cold start process of a fuel cell provided by an exemplary embodiment of the present application is shown, and the computer device includes:

[0137] The processor 801 includes one or more processing cores. The processor 801 executes various functional applications and data processing by running software programs and modules.

[0138] The receiver 802 and the transmitter 803 can be implemented as a communication component, and the communication component can be a communication chip. Optionally, the communication component can be implemented to include a signal transmission function. That is, the transmitter 803 can be used to transmit a control signal to the image acquisition device and the scanning device, and the receiver 802 can be used to receive the corresponding feedback instruction.

[0139] The memory 804 is connected to the processor 801 via a bus 805 .

[0140] The memory 804 may be used to store at least one instruction, and the processor 801 may be used to execute the at least one instruction to implement each step in the above method embodiment.

[0141] An embodiment of the present application also provides a computer-readable storage medium, which stores at least one instruction, at least one program, code set or instruction set, which is loaded and executed by a processor to implement the above-mentioned control method of the air system of the fuel cell cold start process.

[0142] The present application also provides a computer program product or a computer program, which includes a computer instruction stored in a computer-readable storage medium. A processor of a computer device reads the computer instruction from the computer-readable storage medium, and the processor executes the computer instruction, so that the computer device executes the control method of the air system of the fuel cell cold start process described in any of the above embodiments.

[0143] Optionally, the computer readable storage medium may include: a read-only memory (ROM), a random access memory (RAM), a solid state drive (SSD), or an optical disk. Among them, the random access memory may include a resistance random access memory (ReRAM) and a dynamic random access memory (DRAM). The serial numbers of the above embodiments of the present application are only for description and do not represent the advantages and disadvantages of the embodiments.

[0144] It should be understood that the specific examples in this article are only intended to help those skilled in the art to better understand the present disclosure, rather than to limit the scope of the present application.

[0145] It is understood that in the various implementations of this specification, the size of the sequence number of each process does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the present disclosure.

[0146] It can be understood that the various implementation modes described in this specification can be implemented individually or in combination, and the present disclosure is not limited to this.

[0147] Unless otherwise stated, all technical and scientific terms used in this disclosure have the same meaning as those generally understood by those skilled in the art of the technical field of this specification. The terms used in this specification are only for the purpose of describing specific embodiments and are not intended to limit the scope of this specification. The term "and / or" used in this specification includes any and all combinations of one or more related listed items. The singular forms of "a", "above", and "the" used in this disclosure and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0148] It can be understood that the processor of the present disclosure can be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method implementation method can be completed by the hardware integrated logic circuit or software instructions in the processor. The above processor can be a general processor, a digital signal processor (DigitalSignalProcessor, DSP), an application-specific integrated circuit (Application Specific Integrated Circuit, ASIC), a field programmable gate array (Field Programmable Gate Array, FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the present disclosure can be implemented or executed. The general processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in the present disclosure can be directly embodied as a hardware decoding processor to perform, or the hardware and software modules in the decoding processor can be combined to perform. The software module can be located in a mature storage medium in the field such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware.

[0149] It is understood that the memory in the present disclosure may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memory. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (programmable ROM, PROM), an erasable programmable read-only memory (erasable PROM, EPROM), an electrically erasable programmable read-only memory (EEPROM) or a flash memory. The volatile memory may be a random access memory (RAM). It should be noted that the memory of the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0150] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this specification.

[0151] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method implementation methods and will not be repeated here.

[0152] In the several embodiments provided in this specification, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device implementation described above is only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0153] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0154] In addition, each functional unit in each embodiment of the present specification may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0155] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this specification, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the method described in each embodiment of this specification. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., various media that can store program codes.

[0156] The above is only a specific implementation of this specification, but the protection scope of this application is not limited thereto. Any technician familiar with this technical field can easily think of changes or substitutions within the technical scope disclosed in this specification, which should be included in the protection scope of this specification. Therefore, the protection scope of this application should be based on the protection scope of the claims.

Claims

1. A method for controlling an air system during a cold start of a fuel cell, characterized in that: The method is applied to a control device of an air system during a cold start process of a fuel cell, the device comprising a controller, a first air flow meter, an air compressor, a fuel cell stack, a back pressure valve, a bypass valve, a second air flow meter, a stack inlet coolant temperature sensor, a stack outlet coolant temperature sensor, and a pressure sensor; The method comprises: Determining the air flow rate entering the stack, the air pressure entering the stack, the target air flow rate, the target air pressure, the target air pressure correction value, the basic opening value of the back pressure valve, and the basic opening value of the bypass valve; Based on the target air flow rate and the target air pressure, determine the speed feedforward value of the air compressor; according to the target air flow rate and the inlet air flow rate, determine the speed closed-loop adjustment value of the air compressor; by summing the speed feedforward value of the air compressor and the speed closed-loop adjustment value of the air compressor, determine the final speed value of the air compressor; Based on the target air pressure correction value, determine the opening correction value of the back pressure valve; by summing the opening base value of the back pressure valve and the opening correction value of the back pressure valve, determine the final opening value of the back pressure valve; Based on the target air flow rate and the target air pressure correction value, determine the opening correction value of the bypass valve; by summing the opening base value of the bypass valve and the opening correction value of the bypass valve, determine the final opening value of the bypass valve; The air compressor, the back pressure valve and the bypass valve are regulated according to the final value of the air compressor speed, the final value of the opening of the back pressure valve and the final value of the opening of the bypass valve, respectively, so that the inlet air flow rate and the inlet air pressure are stabilized at target values.

2. The control method of the air system during the cold start process of a fuel cell according to claim 1, characterized in that ； The first air flow meter is installed on the pipeline between the air filter and the air compressor, and is used to measure the total air flow entering the air compressor; The second air flow meter is installed on the rear end pipeline of the bypass valve and is used to measure the air bypass flow rate; The inlet coolant temperature sensor is installed at the coolant inlet of the fuel cell stack and is used to measure the inlet coolant temperature; The outgoing coolant temperature sensor is installed at the coolant outlet of the stack and is used to measure the outgoing coolant temperature; The pressure sensor is installed at the air inlet of the fuel cell stack and is used to measure the air pressure entering the stack; The controller is used to regulate the air compressor, the back pressure valve and the bypass valve according to the collected sensor signals and flow meter signals, so that the inlet air flow rate and the inlet air pressure are stabilized at target values.

3. The method for controlling the air system of a fuel cell during a cold start according to claim 2, characterized in that: The step of determining the air flow rate of the stack includes: Obtaining a total air flow and an air bypass flow measured by the first air flow meter and the second air flow meter; Determine the stack air flow rate by subtracting the total air flow rate from the air bypass flow rate; The step of determining the air pressure for entering the stack comprises: The stack air pressure measured by the pressure sensor is obtained.

4. The method for controlling the air system of a fuel cell during a cold start process according to claim 2, characterized in that: Determining the target air flow rate includes: Determine the target air flow rate by multiplying the theoretical required air flow rate by the target excess air coefficient; Determining the target air pressure correction value includes: Acquiring the inlet coolant temperature and the outlet coolant temperature measured by the inlet coolant temperature sensor and the outlet coolant temperature sensor; Based on the inlet coolant temperature and the outlet coolant temperature, a start-up temperature is initialized in combination with a power-on switch signal to determine a start-up temperature; determining the target air pressure correction value according to the starting temperature; Determining the target air pressure includes: According to the target current, determine the target air pressure base value; The target air pressure is determined by summing the target air pressure correction value and the target air pressure base value.

5. The control method of the air system during the cold start process of a fuel cell according to claim 4, characterized in that: The method of initializing the startup temperature based on the inlet coolant temperature and the outlet coolant temperature in combination with a power-on switch signal to determine the startup temperature includes: In response to the controller being powered on, the power-on switch signal is 1, the controller enters a power-on initialization state, and the power-on initialization state flag is set from 0 to 1; Taking the smaller one of the inlet coolant temperature and the outlet coolant temperature as the starting reference temperature; In response to the controller detecting that the power-on initialization state flag is 1, the startup reference temperature at that moment is recorded as the startup temperature, that is, the startup temperature is only calculated and kept fixed in the power-on initialization state, and is no longer updated during subsequent startup and operation processes.

6. The method for controlling the air system of a fuel cell during a cold start process according to claim 2, characterized in that: Determining the opening base value of the back pressure valve includes: Determine the basic opening value of the back pressure valve by calibrating the basic opening amount of the back pressure valve; Determining the basic value of the opening of the bypass valve includes: Based on the target air flow rate, a basic opening value of the bypass valve is determined.

7. The control method of the air system during the cold start process of a fuel cell according to claim 6, characterized in that: The basic opening calibration amount of the back pressure valve is an opening value between fully open and fully closed.

8. The method for controlling the air system of a fuel cell during cold start according to claim 1, characterized in that: Determining a closed-loop adjustment value of the speed of the air compressor according to the target air flow rate and the stack air flow rate includes: determining an air flow difference according to the target air flow and the stack inlet air flow; A PID control calculation is performed based on the air flow difference to determine a closed-loop adjustment value of the speed of the air compressor.

9. The method for controlling the air system of a fuel cell during a cold start process according to any one of claims 1 to 8, characterized in that: The controller comprises: a determination module, used to determine the air flow rate of the stack, the air pressure of the stack, the target air flow rate, the target air pressure, the target air pressure correction value, the basic opening value of the back pressure valve and the basic opening value of the bypass valve; The determination module is further configured to determine a speed feedforward value of the air compressor based on the target air flow rate and the target air pressure; determine a speed closed-loop adjustment value of the air compressor according to the target air flow rate and the inlet air flow rate; and determine a final speed value of the air compressor by summing the speed feedforward value of the air compressor and the speed closed-loop adjustment value of the air compressor; The determination module is further used to determine the opening correction value of the back pressure valve based on the target air pressure correction value; and to determine the final opening value of the back pressure valve by summing the opening base value of the back pressure valve and the opening correction value of the back pressure valve; The determination module is further configured to determine an opening correction value of the bypass valve based on the target air flow rate and the target air pressure correction value; and determine a final opening value of the bypass valve by summing the opening base value of the bypass valve and the opening correction value of the bypass valve; The control module is used to control the air compressor, the back pressure valve and the bypass valve according to the final value of the speed of the air compressor, the final value of the opening of the back pressure valve and the final value of the opening of the bypass valve, so as to stabilize the inlet air flow and the inlet air pressure at the target value.

10. A computer device, characterized in that: The computer device includes a processor and a memory, wherein the memory stores at least one instruction, at least one program, a code set or an instruction set, and the at least one instruction, at least one program, a code set or an instruction set is loaded and executed by the processor to implement the control method of the air system of the fuel cell cold start process as described in any one of claims 1 to 8.

Images