Control method of fuel cell air compressor

Abstract

The invention discloses a control method of a fuel cell air compressor. The control method comprises the following steps: calculating a target flow and a target pressure ratio, matching a first table to obtain an initial target rotating speed, and adjusting the rotating speed of a motor to be close to the initial target rotating speed; the current flow is calculated according to a first empirical formula, the first target rotating speed and the target opening degree are iteratively updated according to the difference value between the current flow and the target flow and the environment temperature, and the motor rotating speed and the bypass valve opening degree are adjusted to be the updated first target rotating speed and the updated target opening degree; according to a second empirical formula, the pressure and flow of the current surge point are calculated, then the distance between the current working condition point and the current surge point is calculated, if the distance is smaller than a preset second threshold value, a second table is matched to obtain a corresponding correction coefficient, the correction coefficient and the first target rotating speed are added to obtain a second target rotating speed, and the second target rotating speed is calculated. And adjusting the motor speed to the second target speed. According to the method, accurate control over the air compressor is achieved through a built-in empirical formula, and surge can be avoided.

Description

technical field [0001] The invention relates to the field of fuel cells, in particular to a control method of a fuel cell air compressor. Background technique [0002] Energy issues have long attracted global attention, especially in recent years with the rapid development of new energy sources. Hydrogen has accumulated as a clean energy source. In the context of carbon neutrality, fuel cells have become a new focus. [0003] The fuel cell relies on the reaction of hydrogen and oxygen to generate water, so hydrogen supply and oxygen supply are the core of its working logic. As the actuator of air supply, the flow control of the air compressor is very important, which affects the output characteristics and safety of the fuel cell. characteristic. Long-term insufficient air supply can reduce battery life and damage proton exchange membranes. [0004] If the working flow characteristics of the air compressor can be calculated and evaluated online, it can not only assist the e...

AI Technical Summary

Problems solved by technology

[0005]The traditional air compressor control method still retains the actuator control logic of the fuel age, adopts the calibration method of the working condition look-up table, and only uses the motor to perform a closed-loop speed control on itself Control, unable to perceive and evaluate the system flow, and the control accuracy is limited. Under the interference of some environmental factors, the basic control cannot be identified and adjusted by itself, which is likely to cause surge and affect the working characteristics and life of the fuel cell.

[0006] In order to improve environmental adaptability, patent CN113050523 discloses an adaptive decoupling control method for fuel cell air supply system, through expected signal preprocessing, PID feedback controller, Decoupling controllers, sensor signal processing and other steps make the system flow as expected, but cannot solve the problem of surge

[0007] In order to solve the problem of surge, patent CN109424575 discloses a flow control method, device and vehicle-mounted equipment, by looking up a preset chart to judge Does the air compressor work in the preset surge area, and adjust the bypass valve when working in the preset surge area, so as to keep the air input into the fuel cell constant, but the preset chart does not match the environmental changes well On the one hand, the dimension of the table will affect the accuracy. For example, if a table is limited to 10*10, if there are a total of 100 blanks, it will limit the amount of data to be filled in, and the simplification of the filled data will affect the accuracy; on the other hand, If the working conditions change, the preset chart may not be accurate, and there will be interpolation. In the case of interpolation, if the fineness of the data in the table is not enough, for example, the distance between two data points is too far, it will make the The point accuracy of interpolation between points is affected

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