Temperature control method for fuel cell in fuel cell vehicle

Abstract

The invention provides a temperature control method for a fuel cell in a fuel cell vehicle. The temperature control method comprises the steps that: a steady-state power temperature compensation duty ratio of the fuel cell is obtained through measurement and calculation by a whole vehicle controller; then, the whole vehicle controller multiplies the steady-state power temperature compensation duty ratio of the fuel cell by the sum of an environment temperature compensation duty ratio and 1, so as to obtain a fan duty ratio corresponding to the cooling power of a heat dissipation system, and the fan controller controls a fan rotating speed according to the fan duty ratio corresponding to the cooling power of the heat dissipation system; afterwards, the whole vehicle control unit selects a dynamic temperature compensation duty ratio of the fuel cell in real time according to an absolute value of the difference between the actual temperature of a water inlet of the fuel cell and the set required temperature of the water inlet of the fuel cell, adds the dynamic temperature compensation duty ratio of the fuel cell and the fan duty ratio corresponding to the cooling power of the heat dissipation system to obtain a fan duty ratio corresponding to the final cooling power of the heat dissipation system, and updates the fan duty ratio to a fan duty ratio corresponding to the cooling power of the heat dissipation system in real time. The temperature control method is simple and feasible, and the temperature of the fuel cell can be rapidly and accurately reduced.

Description

technical field [0001] The invention relates to a method for controlling the temperature of a fuel cell in a fuel cell vehicle. Background technique [0002] As an important branch of new energy development, fuel cells have the characteristics of high energy conversion efficiency and high environmental friendliness. A chemical reaction occurs inside the fuel cell through the proton exchange membrane to convert chemical energy into electrical energy and realize energy conversion. During the process of energy conversion, heat will be generated. A moderate temperature can improve the activity of the catalyst on the electrolyte membrane and increase the diffusion coefficient of hydrogen and oxygen entering the stack; however, if the temperature is too high, it will make the proton exchange membrane The loss of water increases the partial pressure of water vapor and dehydrates the membrane, seriously affecting the work of the fuel cell. Fuel cell vehicles are generally equipped...

AI Technical Summary

Problems solved by technology

In the process of energy conversion, heat will be generated. A moderate temperature can improve the activity of the catalyst on the electrolyte membrane, increase the diffusion coefficient of hydrogen and oxygen entering the stack, and make the gas diffuse more fully; The loss of water will increase the partial pressure of water vapor and dehydrate the membrane, which will seriously affect the operation of the fuel cell.

Fuel cell vehicles are generally equipped with a heat dissipation system specially for cooling the fuel cell. In the heat dissipation system, coolant circulation is generally used to reduce the temperature of the fuel cell. The cooling of the coolant is generally achieved by fans, etc., and most of the coolant is used Water, the large specific heat capacity of water and the long pipeline of the heat dissipation system lead to a large amount of inertia in the change of water temperature, and often the adjustment will lag and oscillate

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