CN116885243A - Fuel cell air system control method and device - Google Patents

Abstract

The invention discloses a control method and a control device for an air system of a fuel cell, and relates to the technical field of fuel cells. The invention determines the target electric pile power of the fuel cell according to the whole vehicle required power, determines the target air intake humidity according to the target electric pile power, determines the internal actual humidity of the electric pile according to the target electric pile power and the electric pile high-frequency impedance, determines the control opening of the humidity regulating valve according to the target air intake humidity and the internal actual humidity of the electric pile, and controls the opening of the air system humidity regulating valve according to the control opening of the humidity regulating valve so as to ensure that the internal actual humidity of the electric pile reaches the target air intake humidity.

Description

Fuel cell air system control method and device

Technical field

The present invention relates to the technical field of fuel cells, and in particular to a fuel cell air system control method and device.

Background technique

The humidity of the proton exchange membrane of the fuel cell directly affects the performance of the fuel cell. When the humidity of the proton exchange membrane is moderate, the internal resistance of the fuel cell is low and the load capacity is strong; when the proton exchange membrane is too dry, the internal resistance of the fuel cell increases and the load capacity decreases. When the water content of the proton exchange membrane is too high, it will cause the cathode to be flooded, causing the performance of the fuel cell system to decay, and also affecting the life of the fuel cell system. At present, the humidity control of the fuel cell system is open-loop control, which has the problem of poor control accuracy and cannot make the internal humidity of the fuel cell moderate.

Contents of the invention

The present invention solves the technical problem of how to make the internal humidity of the fuel cell moderate by providing a fuel cell air system control method and device.

On the one hand, the present invention provides the following technical solutions:

A fuel cell air system control method, including:

Obtain the vehicle power demand, and determine the target stack power of the fuel cell based on the vehicle power demand;

According to the preset corresponding relationship between stack power and air inlet humidity, determine the target air inlet humidity corresponding to the target stack power;

Obtain the high-frequency impedance of the fuel cell stack;

According to the preset corresponding relationship between the stack impedance and the internal humidity of the stack under the target stack power, determine the actual humidity inside the stack corresponding to the high-frequency impedance of the stack;

Determine the control opening of the humidity control valve according to the target air inlet humidity and the actual humidity inside the stack;

The opening of the humidity control valve of the air system is controlled according to the control opening of the humidity control valve, so that the actual humidity inside the stack reaches the target air intake humidity.

Preferably, obtaining the high-frequency impedance of the fuel cell stack includes:

Apply AC excitation of different frequencies to the DC step-up transformer of the fuel cell;

Obtain the stack output voltage and stack output current under each of the AC excitations;

Extract the voltage component in the output voltage of each of the stacks and the current component in the output current of each of the stacks;

Calculate the ratio of the voltage component corresponding to each AC excitation and the current component to obtain the impedance corresponding to the AC excitation;

The impedance analysis method is used to analyze multiple impedances corresponding to multiple AC excitations to obtain the high-frequency impedance of the stack.

Preferably, the step of determining the humidity control valve control opening based on the target air inlet humidity and the actual humidity inside the stack includes:

The deviation between the target air inlet humidity and the actual humidity inside the stack is input to the humidity PID controller, and the humidity control valve control opening is output.

Preferably, after obtaining the vehicle power demand, determining the target stack power of the fuel cell based on the vehicle power demand, and before controlling the opening of the air system humidity control valve according to the humidity control valve opening, Also includes:

According to the preset corresponding relationship between stack power and humidity control valve opening, determine the target humidity control valve opening corresponding to the target stack power;

Input the target humidity control valve opening into the humidity feedforward controller and output the humidity control valve feedforward opening;

The method of controlling the opening of the humidity regulating valve of the air system according to the humidity regulating valve opening also includes:

If the sum of the control opening of the humidity control valve and the feedforward opening of the humidity control valve is lower than the first opening threshold, the opening of the humidity control valve is controlled to be the sum of the control opening of the humidity control valve and the The sum of the feedforward openings of the humidity control valve;

If the sum of the control opening of the humidity control valve and the feedforward opening of the humidity control valve is higher than the first opening threshold, the opening of the humidity control valve is controlled to be the first opening threshold.

Preferably, after obtaining the vehicle power demand and determining the target stack power of the fuel cell based on the vehicle power demand, the method further includes:

According to the preset corresponding relationship between stack power and stack air flow, determine the target stack air flow corresponding to the target stack power;

Obtain the actual air flow into the stack of the air system;

Input the deviation between the target air flow into the pile and the actual air flow into the pile into the flow PID controller, and output the air compressor control speed;

The rotation speed of the air compressor of the air system is controlled according to the air compressor control speed, so that the actual air flow rate entering the stack reaches the target air flow rate entering the stack.

Preferably, controlling the rotation speed of the air compressor of the air system according to the control speed of the air compressor includes:

Controlling the rotation speed of the air compressor is the control rotation speed of the air compressor.

Preferably, after determining the target air flow rate into the stack corresponding to the target stack power according to the preset corresponding relationship between the stack power and the air flow rate into the stack, the air system is controlled according to the control speed of the air compressor. Before the speed of the air compressor, it also includes:

Determine the target air compressor speed corresponding to the target air flow rate entering the stack according to the preset relationship between the air flow rate entering the stack and the rotational speed of the air compressor;

Input the target air compressor speed to the flow feedforward controller and output the air compressor feedforward speed;

Controlling the speed of the air compressor of the air system according to the control speed of the air compressor includes:

If the sum of the control speed of the air compressor and the feedforward speed of the air compressor is lower than the speed threshold, the speed of the air compressor is controlled to be the control speed of the air compressor and the feedforward speed of the air compressor. Sum;

If the sum of the air compressor control speed and the air compressor feedforward speed is higher than the speed threshold, the speed of the air compressor is controlled to be the speed threshold.

Preferably, after obtaining the vehicle power demand and determining the target stack power of the fuel cell based on the vehicle power demand, the method further includes:

According to the preset corresponding relationship between stack power and stack inlet air pressure, determine the target stack inlet air pressure corresponding to the target stack power;

Obtain the actual incoming air pressure of the air system;

Input the deviation between the target air pressure into the pile and the actual air pressure into the pile into the pressure PID controller, and output the back pressure valve to control the opening;

The opening of the back pressure valve of the air system is controlled according to the control opening of the back pressure valve, so that the actual air pressure entering the stack reaches the target air pressure entering the stack.

Preferably, controlling the opening of the air system back pressure valve according to the back pressure valve control opening includes:

Controlling the opening of the back pressure valve is the control of the opening of the back pressure valve.

Preferably, after determining the target stack air pressure corresponding to the target stack power according to the preset stack power-stack air pressure correspondence relationship, the air is controlled according to the back pressure valve control opening. Before the opening of the system back pressure valve, it also includes:

Determine the target back pressure valve opening corresponding to the target air pressure entering the stack according to the preset relationship between the air pressure entering the stack and the opening of the back pressure valve;

Input the target back pressure valve opening into the pressure feedforward controller and output the back pressure valve feedforward opening;

Controlling the opening of the air system back pressure valve according to the back pressure valve control opening includes:

If the sum of the control opening of the back pressure valve and the feedforward opening of the back pressure valve is lower than the second opening threshold, the opening of the back pressure valve is controlled to be the sum of the control opening of the back pressure valve and the feedforward opening of the back pressure valve. The sum of the feedforward openings of the back pressure valve;

If the sum of the control opening of the back pressure valve and the feedforward opening of the back pressure valve is higher than the second opening threshold, the opening of the back pressure valve is controlled to be the second opening threshold.

Preferably, after obtaining the actual inlet air pressure of the air system, the method further includes:

If the actual air pressure entering the reactor is higher than the safety threshold, the drain valve of the air system is opened.

Preferably, after obtaining the actual inlet air pressure of the air system, the method further includes:

If the actual air pressure entering the pile is higher than the pressure value corresponding to the actual air flow entering the pile, open the drain valve of the air system;

If the actual air entering the pile pressure is lower than the pressure value corresponding to the actual air entering the pile flow rate, the drain valve is closed.

On the other hand, the present invention also provides the following technical solutions:

A fuel cell air system control device, including:

The first determination module is used to obtain the vehicle power demand, and determine the target stack power of the fuel cell based on the vehicle power demand;

The second determination module is used to determine the target air intake humidity corresponding to the target stack power according to the preset correspondence relationship between stack power and air intake humidity;

Acquisition module, used to obtain the high-frequency impedance of the fuel cell stack;

The third determination module is used to determine the actual humidity inside the stack corresponding to the high-frequency impedance of the stack according to the preset corresponding relationship between stack impedance and stack internal humidity under the target stack power;

The fourth determination module is used to determine the control opening of the humidity control valve according to the target air inlet humidity and the actual humidity inside the stack;

The humidity control valve control module is used to control the opening of the humidity control valve of the air system according to the control opening of the humidity control valve, so that the actual humidity inside the stack reaches the target air intake humidity.

On the other hand, the present invention also provides the following technical solutions:

An electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements any of the above fuel cell air system control methods.

On the other hand, the present invention also provides the following technical solutions:

A computer-readable storage medium has a computer program stored on the computer-readable storage medium, and the computer program implements any of the above fuel cell air system control methods when executed by a processor.

One or more technical solutions provided by the present invention have at least the following technical effects or advantages:

The invention determines the target stack power of the fuel cell based on the vehicle power demand, determines the target air intake humidity based on the target stack power, determines the actual humidity inside the stack based on the target stack power and stack high-frequency impedance, and determines the target air intake humidity based on the target stack power. The air humidity and the actual humidity inside the stack determine the control opening of the humidity control valve. The opening of the humidity control valve in the air system is controlled according to the control opening of the humidity control valve, so that the actual humidity inside the stack reaches the target air inlet humidity. Since the target air The inlet air humidity is the internal humidity of the stack that optimizes the load capacity of the fuel cell under the target stack power. This can make the internal humidity of the fuel cell moderate and improve the load capacity of the fuel cell.

Description of the drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present invention. Those of ordinary skill in the art can also obtain other drawings based on these drawings without exerting creative efforts.

Figure 1 is a partial structural schematic diagram of a fuel cell in an embodiment of the present invention;

Figure 2 is a flow chart of a fuel cell air system control method in an embodiment of the present invention;

Figure 3 is a schematic diagram of a fuel cell air system control device in an embodiment of the present invention.

Detailed ways

Embodiments of the present invention solve the technical problem of how to make the internal humidity of a fuel cell moderate by providing a fuel cell air system control method and device.

In order to better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

As shown in Figure 1, the fuel cell of this embodiment includes a stack, an air system and a DC step-up transformer. The air system includes an air compressor, a humidity control valve, a back pressure valve and a relief valve. The air outlets of the air compressor are respectively Connect the drain valve and the air inlet of the stack through the humidity control valve. The air outlet of the stack is connected to the back pressure valve. The DC boost transformer is connected to the stack and the high-voltage system of the vehicle. Among them, the air compressor is used to control the flow of air entering the stack, the humidity regulating valve is used to adjust the humidity of the air entering the stack, the back pressure valve and the relief valve jointly control the pressure of the air entering the stack, and the DC boost transformer is used to convert the output voltage of the stack The voltage is boosted to the vehicle bus voltage to provide power for the entire vehicle. Under normal circumstances, the drain valve is closed.

As shown in Figure 2, the fuel cell air system control method of this embodiment includes:

Step S1, obtain the vehicle power demand, and determine the target stack power of the fuel cell based on the vehicle power demand;

Step S2, determine the target air inlet humidity corresponding to the target stack power according to the preset correspondence relationship between stack power and air inlet humidity;

Step S3, obtain the high-frequency impedance of the fuel cell stack;

Step S4, determine the actual humidity inside the stack corresponding to the high-frequency impedance of the stack according to the corresponding relationship between stack impedance and stack internal humidity under the preset target stack power;

Step S5, determine the control opening of the humidity control valve based on the target air inlet humidity and the actual humidity inside the stack;

Step S6: Control the opening of the humidity regulating valve of the air system according to the control opening of the humidity regulating valve, so that the actual humidity inside the stack reaches the target air intake humidity.

In step S1, the power demand of the whole vehicle determines the power of the stack. The relationship between the power demand of the whole vehicle and the target power of the stack is target stack power = the power demand of the whole vehicle/the energy conversion efficiency of the stack.

In step S2, the corresponding relationship between the stack power and the air inlet humidity can be a table. The table records the air inlet humidity corresponding to each stack power, which represents the optimal air inlet humidity for the stack power. suitable.

Before step S4, this embodiment will control the stack power to be at different values. Under each stack power, a large amount of stack impedance data of the fuel cell and the internal humidity data of the stack when detecting the impedance of each stack are obtained. According to each stack power, A large amount of stack impedance-pile internal humidity data under the stack power establishes the corresponding relationship between the stack impedance-pile internal humidity under the stack power, so that the stack impedance-pile internal humidity under each stack power can be obtained. Humidity correspondence. In this way, after step S1 determines the target stack power and step S3 obtains the stack high-frequency impedance of the fuel cell, the voltage corresponding to the stack high-frequency impedance can be determined based on the stack impedance-stack internal humidity correspondence relationship under the target stack power. Actual humidity inside the pile.

Step S6 controls the opening of the air system humidity regulating valve according to the humidity regulating valve control opening, so that the actual humidity inside the stack reaches the target air inlet humidity. Since the target air inlet humidity is the fuel cell load capacity under the target stack power Optimal internal humidity of the stack, which can make the internal humidity of the fuel cell moderate and improve the load capacity of the fuel cell.

Step S3 in this embodiment may include: applying AC excitations of different frequencies to the DC step-up transformer of the fuel cell; obtaining the stack output voltage and stack output current under each AC excitation; extracting the output voltage of each stack The voltage component and the current component in the output current of each stack; calculate the ratio of the voltage component and current component corresponding to each AC excitation to obtain the impedance corresponding to the AC excitation; use the impedance analysis method to analyze multiple AC excitations corresponding to The impedance is analyzed to obtain the high-frequency impedance of the stack.

The DC boost transformer includes an internal resistance detection module, an output current sensor, an output voltage sensor and a boost DCDC module. The internal resistance detection module can provide AC excitation disturbance for fuel cell internal resistance detection, and the AC excitation acts on the boost DCDC module. BOOST boost circuit can change the input current of the boost DCDC module. The output current sensor can detect the stack output current, and the output voltage sensor can detect the stack output voltage. The AC signal extraction algorithm can be used to extract the voltage component in the stack output voltage and the current component in the stack output current at each frequency. The impedance at the excitation frequency = the voltage component corresponding to the excitation frequency/the current corresponding to the excitation frequency Portion. By continuously changing the frequency of AC excitation, the impedance at different excitation frequencies can be obtained. By using the impedance analysis method to analyze multiple impedances corresponding to multiple AC excitations, the high-frequency impedance of the stack can be obtained.

Step S5 of this embodiment may include: inputting the deviation between the target air inlet humidity and the actual humidity inside the stack into the humidity PID controller, and outputting the humidity control valve to control the opening. PID control is a mature technology. Since the control opening of the humidity control valve is obtained through PID control, PID control is a closed-loop control with high control accuracy, which can make the control opening of the humidity control valve more accurate.

It can be understood that if the opening of the humidity control valve of the air system is controlled by the humidity control valve, the actual humidity inside the stack will gradually approach the target air inlet humidity and stabilize near the target air inlet humidity. Therefore, in order to make the actual humidity inside the stack reach the target air inlet humidity, in step S6, controlling the opening of the humidity regulating valve of the air system according to the controlling opening of the humidity regulating valve may include: controlling the opening of the humidity regulating valve to the humidity regulating The valve controls the opening.

A method of controlling the opening of the humidity regulating valve of the air system based on the humidity regulating valve opening is also provided here. After step S1 and before step S6, the fuel cell air system control method of this embodiment includes: determining the target corresponding to the target stack power according to the preset correspondence relationship between stack power-air inlet humidity-humidity regulating valve opening. Humidity control valve opening; input the target humidity control valve opening into the humidity feedforward controller and output the humidity control valve feedforward opening. In step S6, controlling the opening of the humidity control valve of the air system according to the control opening of the humidity control valve also includes: if the sum of the control opening of the humidity control valve and the feedforward opening of the humidity control valve is lower than the first opening threshold, then The opening of the controlled humidity control valve is the sum of the control opening of the humidity control valve and the feedforward opening of the humidity control valve; if the sum of the control opening of the humidity control valve and the feedforward opening of the humidity control valve is higher than the first opening threshold, Then the opening of the humidity control valve is controlled to be the first opening threshold.

Among them, the control opening of the humidity control valve is obtained through PID control, and the feedforward opening of the humidity control valve is obtained through feedforward control. PID control is closed-loop control, feedforward control is open-loop control, and controlling the opening of the humidity control valve is humidity control. The sum of the valve control opening and the humidity control valve feedforward opening can improve the control accuracy of the actual humidity inside the stack through the cooperation of closed-loop control and open-loop control, making the internal humidity of the fuel cell more moderate. If the sum of the humidity control valve control opening and the humidity control valve feedforward opening is higher than the first opening threshold, it means that the sum of the humidity control valve control opening and the humidity control valve feedforward opening exceeds the allowable limit of the humidity control valve or If the maximum opening that can be achieved, the opening of the humidity control valve is controlled to be the maximum opening that is allowed or achievable by the humidity control valve.

This embodiment not only needs to control the internal humidity of the fuel cell to be moderate, but also needs to control the actual air flow into the stack of the air system to be moderate to improve the load capacity of the fuel cell. Therefore, after step S1, the fuel cell air system control method of this embodiment also includes: determining the target air flow rate into the stack corresponding to the target stack power according to the preset correspondence relationship between stack power and air flow into the stack; obtaining the air system The actual air flow into the pile; input the deviation between the target air flow into the pile and the actual air flow into the pile into the flow PID controller, and output the air compressor control speed; control the air system air compressor speed according to the air compressor control speed to Make the actual air flow into the pile reach the target air flow into the pile.

Similarly, the corresponding relationship between the stack power and the air flow into the stack can be a table. The table records the air flow into the stack corresponding to each stack power, which represents the most appropriate air flow into the stack at the stack power. PID control is a mature technology. It can be understood that if the speed of the air compressor of the air system is controlled by the air compressor control speed, the actual air flow rate of the air system will gradually approach the target air flow rate and stabilize at the target air flow rate. near air flow. The speed of the air compressor in the air system is controlled according to the air compressor control speed. Since the air compressor control speed is obtained through PID control, the PID control is a closed-loop control with high control accuracy, which can make the actual air flow into the pile closer to the target air flow into the pile. , which can make the actual air flow into the stack of the air system moderate.

As mentioned above, if the speed of the air compressor in the air system is controlled to be the air compressor control speed, the actual air flow into the pile of the air system will gradually approach the target air flow into the pile and stabilize near the target air flow into the pile. Therefore, controlling the speed of the air compressor of the air system according to the air compressor control speed may include: controlling the speed of the air compressor to be the air compressor control speed.

A method of controlling the speed of the air compressor in the air system based on the air compressor control speed is also provided here. According to the preset corresponding relationship between stack power and air flow into the stack, after determining the target air flow into the stack corresponding to the target stack power and before controlling the speed of the air compressor of the air system according to the control speed of the air compressor, in this embodiment The fuel cell air system control method may also include: determining the target air compressor speed corresponding to the target air flow into the stack according to the preset relationship between the air flow into the stack and the speed of the air compressor; inputting the target air compressor speed before the flow rate. Feedback controller outputs the feedforward speed of the air compressor. Controlling the speed of the air compressor in the air system according to the air compressor control speed may include: If the sum of the air compressor control speed and the air compressor feedforward speed is lower than the speed threshold, then controlling the air compressor speed is air compressor control. The sum of the rotational speed and the feedforward rotational speed of the air compressor; if the sum of the control rotational speed of the air compressor and the feedforward rotational speed of the air compressor is higher than the rotational speed threshold, the rotational speed of the air compressor is controlled to the rotational speed threshold.

Among them, the air compressor control speed is obtained through PID control, and the air compressor feedforward speed is obtained through feedforward control. PID control is closed-loop control, feedforward control is open-loop control, and the controlled speed of the air compressor is the air compressor control speed. Together with the feedforward speed of the air compressor, the control accuracy of the actual air flow into the reactor can be improved through the cooperation of closed-loop control and open-loop control, making the actual air flow into the reactor more moderate. If the sum of the air compressor control speed and the air compressor feedforward speed is higher than the speed threshold, it means that the sum of the air compressor control speed and the air compressor feedforward speed exceeds the maximum speed allowed or achievable by the air compressor. Then control the speed of the air compressor to the maximum speed allowed or achievable by the air compressor.

This embodiment not only needs to control the internal humidity of the fuel cell to be moderate, but also needs to control the actual air pressure entering the stack of the air system to be moderate to improve the load capacity of the fuel cell. Therefore, after step S1, the fuel cell air system control method of this embodiment also includes: determining the target stack air pressure corresponding to the target stack power according to the preset stack power-stack air pressure correspondence relationship; obtaining the air system The actual entering air pressure of the reactor; input the deviation between the target entering air pressure and the actual entering air pressure into the pressure PID controller, and output the back pressure valve to control the opening; control the opening of the air system back pressure valve according to the back pressure valve control opening degree so that the actual air pressure entering the reactor reaches the target air pressure entering the reactor.

Similarly, the corresponding relationship between stack power and stack inlet air pressure can be a table. The table records the stack inlet air pressure corresponding to each stack power, which represents the most appropriate stack inlet air pressure for this stack power. PID control is a mature technology. It can be understood that if the opening of the back pressure valve of the air system is controlled by the back pressure valve, the actual inlet air pressure of the air system will gradually approach the target inlet air pressure and stabilize at the target near the air pressure entering the pile. The opening of the back pressure valve of the air system is controlled according to the control opening of the back pressure valve. Since the control opening of the back pressure valve is obtained through PID control, the PID control is a closed-loop control with high control accuracy, which can make the actual air pressure entering the reactor closer to the target. The reactor air pressure can make the actual inlet air pressure of the air system moderate.

As mentioned above, if the opening of the back pressure valve of the air system is controlled by the back pressure valve, the actual inlet air pressure of the air system will gradually approach the target inlet air pressure and stabilize near the target inlet air pressure. Therefore, controlling the opening of the back pressure valve of the air system according to the control opening of the back pressure valve may include: controlling the opening of the back pressure valve to be the control opening of the back pressure valve.

Here, a method of controlling the opening of the back pressure valve of the air system based on the back pressure valve control opening is also provided. According to the preset corresponding relationship between stack power and stack inlet air pressure, after determining the target stack inlet air pressure corresponding to the target stack power and before controlling the opening of the air system back pressure valve according to the back pressure valve control opening, this implementation The fuel cell air system control method of the example may further include: determining the target back pressure valve opening corresponding to the target inlet air pressure according to the preset relationship between the stack inlet air pressure and the back pressure valve opening; The valve opening is input to the pressure feedforward controller and the back pressure valve feedforward opening is output. Controlling the opening of the back pressure valve of the air system according to the control opening of the back pressure valve includes: if the sum of the control opening of the back pressure valve and the feed forward opening of the back pressure valve is lower than the second opening threshold, controlling the opening of the back pressure valve The opening is the sum of the back pressure valve control opening and the back pressure valve feedforward opening; if the sum of the back pressure valve control opening and the back pressure valve feedforward opening is higher than the second opening threshold, the back pressure valve is controlled The opening is the second opening threshold.

Among them, the control opening of the back pressure valve is obtained through PID control, and the feed forward opening of the back pressure valve is obtained through feed forward control. PID control is closed loop control, feed forward control is open loop control, and the opening of the back pressure valve is controlled by back pressure. The sum of the valve control opening and the back pressure valve feedforward opening can improve the control accuracy of the actual air pressure entering the reactor through the cooperation of closed-loop control and open-loop control, making the actual air pressure entering the reactor more moderate. If the sum of the back pressure valve control opening and the back pressure valve feedforward opening is higher than the second opening threshold, it means that the sum of the back pressure valve control opening and the back pressure valve feed forward opening exceeds the allowable limit of the back pressure valve or The maximum opening that can be achieved, then the opening of the back pressure valve is controlled to be the maximum opening allowed or achievable by the pressure valve.

Considering that there is a safety risk if the actual air pressure of the air system is too high, in this embodiment, after obtaining the actual air pressure of the air system, the fuel cell air system control method may also include: if the actual air pressure is higher than If the safety threshold is reached, open the relief valve of the air system; if the actual air pressure entering the reactor is higher than the pressure value corresponding to the actual air flow, open the relief valve of the air system; if the actual air pressure entering the reactor is lower than the actual air entering the reactor If the pressure value corresponding to the air flow is reached, the drain valve will be closed.

As shown in Figure 3, this embodiment also provides a fuel cell air system control device, including:

The first determination module is used to obtain the power demand of the whole vehicle and determine the target stack power of the fuel cell according to the power demand of the whole vehicle;

The second determination module is used to determine the target air inlet humidity corresponding to the target stack power according to the preset correspondence relationship between stack power and air inlet humidity;

Acquisition module, used to obtain the high-frequency impedance of the fuel cell stack;

The third determination module is used to determine the actual humidity inside the stack corresponding to the high-frequency impedance of the stack based on the corresponding relationship between stack impedance and stack internal humidity under the preset target stack power;

The fourth determination module is used to determine the control opening of the humidity control valve based on the target air inlet humidity and the actual humidity inside the stack;

The humidity control valve control module is used to control the opening of the humidity control valve of the air system according to the control opening of the humidity control valve, so that the actual humidity inside the stack reaches the target air inlet humidity.

Based on the same inventive concept as the fuel cell air system control method described above, this embodiment also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the steps of any of the fuel cell air system control methods described above are implemented.

Among them, the bus architecture (represented by a bus), the bus can include any number of interconnected buses and bridges, and the bus links together various circuits including one or more processors represented by the processor and memory represented by the memory. The bus can also link together various other circuits such as peripherals, voltage regulators, and power management circuits, which are all well known in the art and therefore will not be described further herein. The bus interface provides the interface between the bus and receivers and transmitters. The receiver and transmitter may be the same element, a transceiver, providing a unit for communicating with various other devices over a transmission medium. The processor is responsible for managing the bus and general processing, while memory can be used to store data used by the processor when performing operations.

Since the electronic equipment introduced in this embodiment is the electronic equipment used to implement the fuel cell air system control method in the embodiment of the present invention, based on the fuel cell air system control method introduced in the embodiment of the present invention, those skilled in the art It is possible to understand the specific implementation manner of the electronic device of this embodiment and its various modifications, so how the electronic device implements the method in the embodiment of the present invention will not be described in detail here. As long as those skilled in the art implement the electronic equipment used in the fuel cell air system control method in the embodiment of the present invention, it will fall within the scope of protection of the present invention.

Based on the same inventive concept as the above-mentioned fuel cell air system control method, the present invention also provides a computer-readable storage medium. A computer program is stored on the computer-readable storage medium. The computer program is implemented when executed by a processor. Any of the above fuel cell air system control methods.

Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each process and/or block in the flowchart illustrations and/or block diagrams, and combinations of processes and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing device to produce a machine, such that the instructions executed by the processor of the computer or other programmable data processing device produce a use A device for realizing the functions specified in one process or multiple processes of the flowchart and/or one block or multiple blocks of the block diagram.

These computer program instructions may also be stored in a computer-readable memory that causes a computer or other programmable data processing apparatus to operate in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including the instruction means, the instructions The device implements the functions specified in a process or processes of the flowchart and/or a block or blocks of the block diagram.

These computer program instructions may also be loaded onto a computer or other programmable data processing device, causing a series of operating steps to be performed on the computer or other programmable device to produce computer-implemented processing, thereby executing on the computer or other programmable device. Instructions provide steps for implementing the functions specified in a process or processes of a flowchart diagram and/or a block or blocks of a block diagram.

Although the preferred embodiments of the present invention have been described, those skilled in the art will be able to make additional changes and modifications to these embodiments once the basic inventive concepts are apparent. Therefore, it is intended that the appended claims be construed to include the preferred embodiments and all changes and modifications that fall within the scope of the invention.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the invention. In this way, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and equivalent technologies, the present invention is also intended to include these modifications and variations.

Claims (15)

1. A fuel cell air system control method, characterized by comprising: Obtain the vehicle power demand, and determine the target stack power of the fuel cell based on the vehicle power demand; According to the preset corresponding relationship between stack power and air inlet humidity, determine the target air inlet humidity corresponding to the target stack power; Obtain the high-frequency impedance of the fuel cell stack; According to the preset corresponding relationship between the stack impedance and the internal humidity of the stack under the target stack power, determine the actual humidity inside the stack corresponding to the high-frequency impedance of the stack; Determine the control opening of the humidity control valve according to the target air inlet humidity and the actual humidity inside the stack; The opening of the humidity control valve of the air system is controlled according to the control opening of the humidity control valve, so that the actual humidity inside the stack reaches the target air intake humidity. 2. The fuel cell air system control method according to claim 1, wherein said obtaining the high-frequency impedance of the fuel cell stack includes: Apply AC excitation of different frequencies to the DC step-up transformer of the fuel cell; Obtain the stack output voltage and stack output current under each of the AC excitations; Extract the voltage component in the output voltage of each of the stacks and the current component in the output current of each of the stacks; Calculate the ratio of the voltage component corresponding to each AC excitation and the current component to obtain the impedance corresponding to the AC excitation; The impedance analysis method is used to analyze multiple impedances corresponding to multiple AC excitations to obtain the high-frequency impedance of the stack. 3. The fuel cell air system control method according to claim 1, wherein determining the humidity control valve control opening according to the target air inlet humidity and the actual humidity inside the stack includes: The deviation between the target air inlet humidity and the actual humidity inside the stack is input to the humidity PID controller, and the humidity control valve control opening is output. 4. The fuel cell air system control method according to claim 3, characterized in that: after obtaining the vehicle power demand and determining the target stack power of the fuel cell according to the vehicle power demand, the fuel cell air system control method is based on the vehicle power demand. Controlling the opening of the humidity control valve Before controlling the opening of the humidity control valve in the air system, it also includes: According to the preset corresponding relationship between stack power and humidity control valve opening, determine the target humidity control valve opening corresponding to the target stack power; Input the target humidity control valve opening into the humidity feedforward controller and output the humidity control valve feedforward opening; The method of controlling the opening of the humidity regulating valve of the air system according to the humidity regulating valve opening also includes: If the sum of the control opening of the humidity control valve and the feedforward opening of the humidity control valve is lower than the first opening threshold, the opening of the humidity control valve is controlled to be the sum of the control opening of the humidity control valve and the The sum of the feedforward openings of the humidity control valve; If the sum of the control opening of the humidity control valve and the feedforward opening of the humidity control valve is higher than the first opening threshold, the opening of the humidity control valve is controlled to be the first opening threshold. 5. The fuel cell air system control method according to claim 1, characterized in that after obtaining the vehicle power demand and determining the target stack power of the fuel cell according to the vehicle power demand, the method further includes: According to the preset corresponding relationship between stack power and stack air flow, determine the target stack air flow corresponding to the target stack power; Obtain the actual air flow into the stack of the air system; Input the deviation between the target air flow into the pile and the actual air flow into the pile into the flow PID controller, and output the air compressor control speed; The rotation speed of the air compressor of the air system is controlled according to the air compressor control speed, so that the actual air flow rate entering the stack reaches the target air flow rate entering the stack. 6. The fuel cell air system control method according to claim 5, wherein controlling the rotation speed of the air system air compressor according to the air compressor control speed includes: Controlling the rotation speed of the air compressor is the control rotation speed of the air compressor. 7. The fuel cell air system control method according to claim 5, wherein the target stack power corresponding to the target stack power is determined according to the preset corresponding relationship between the stack power and the stack air flow rate. After the air flow rate and before controlling the rotation speed of the air compressor of the air system according to the control speed of the air compressor, the method further includes: Determine the target air compressor speed corresponding to the target air flow rate entering the stack according to the preset relationship between the air flow rate entering the stack and the rotational speed of the air compressor; Input the target air compressor speed to the flow feedforward controller and output the air compressor feedforward speed; Controlling the speed of the air compressor of the air system according to the control speed of the air compressor includes: If the sum of the control speed of the air compressor and the feedforward speed of the air compressor is lower than the speed threshold, the speed of the air compressor is controlled to be the control speed of the air compressor and the feedforward speed of the air compressor. Sum; If the sum of the air compressor control speed and the air compressor feedforward speed is higher than the speed threshold, the speed of the air compressor is controlled to be the speed threshold. 8. The fuel cell air system control method according to claim 1, wherein after obtaining the vehicle power demand and determining the target stack power of the fuel cell according to the vehicle power demand, the method further includes: According to the preset corresponding relationship between stack power and stack inlet air pressure, determine the target stack inlet air pressure corresponding to the target stack power; Obtain the actual incoming air pressure of the air system; Input the deviation between the target air pressure into the pile and the actual air pressure into the pile into the pressure PID controller, and output the back pressure valve to control the opening; The opening of the back pressure valve of the air system is controlled according to the control opening of the back pressure valve, so that the actual air pressure entering the stack reaches the target air pressure entering the stack. 9. The fuel cell air system control method according to claim 8, wherein the controlling the opening of the air system back pressure valve according to the back pressure valve control opening includes: Controlling the opening of the back pressure valve is the control of the opening of the back pressure valve. 10. The fuel cell air system control method according to claim 8, wherein the target stack entry corresponding to the target stack power is determined according to a preset correspondence relationship between stack power and stack entry air pressure. After the air pressure and before controlling the opening of the air system back-pressure valve according to the back-pressure valve opening, it also includes: Determine the target back pressure valve opening corresponding to the target air pressure entering the stack according to the preset relationship between the air pressure entering the stack and the opening of the back pressure valve; Input the target back pressure valve opening into the pressure feedforward controller and output the back pressure valve feedforward opening; Controlling the opening of the air system back pressure valve according to the back pressure valve control opening includes: If the sum of the control opening of the back pressure valve and the feedforward opening of the back pressure valve is lower than the second opening threshold, the opening of the back pressure valve is controlled to be the sum of the control opening of the back pressure valve and the feedforward opening of the back pressure valve. The sum of the feedforward openings of the back pressure valve; If the sum of the control opening of the back pressure valve and the feedforward opening of the back pressure valve is higher than the second opening threshold, the opening of the back pressure valve is controlled to be the second opening threshold. 11. The fuel cell air system control method according to claim 8, characterized in that after obtaining the actual inlet air pressure of the air system, it further includes: If the actual air pressure entering the reactor is higher than the safety threshold, the drain valve of the air system is opened. 12. The fuel cell air system control method according to claim 8, characterized in that after obtaining the actual inlet air pressure of the air system, it further includes: If the actual air pressure entering the pile is higher than the pressure value corresponding to the actual air flow entering the pile, open the drain valve of the air system; If the actual air entering the pile pressure is lower than the pressure value corresponding to the actual air entering the pile flow rate, the drain valve is closed. 13. A fuel cell air system control device, characterized in that it includes: The first determination module is used to obtain the vehicle power demand, and determine the target stack power of the fuel cell based on the vehicle power demand; The second determination module is used to determine the target air intake humidity corresponding to the target stack power according to the preset correspondence relationship between stack power and air intake humidity; Acquisition module, used to obtain the high-frequency impedance of the fuel cell stack; The third determination module is used to determine the actual humidity inside the stack corresponding to the high-frequency impedance of the stack according to the preset corresponding relationship between stack impedance and stack internal humidity under the target stack power; The fourth determination module determines the control opening of the humidity control valve according to the target air inlet humidity and the actual humidity inside the stack; The humidity control valve control module is used to control the opening of the humidity control valve of the air system according to the control opening of the humidity control valve, so that the actual humidity inside the stack reaches the target air intake humidity. 14. An electronic device, characterized in that it includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, any one of claims 1-12 is implemented. The fuel cell air system control method according to claim 1. 15. A computer-readable storage medium, characterized in that a computer program is stored on the computer-readable storage medium, and when executed by a processor, the computer program implements the requirements of any one of claims 1-12. The fuel cell air system control method described above.