Abstract: Using the method of combining fluid-solid coupling velocity field and heat transfer field, the temperature field of the maximum heating point of the 560kW mine permanent magnetic coupling applied to the open-pit mine centrifugal load speed regulation process is studied, and the heat loss under the maximum heating point working condition It has a 3rd power relationship with the slip. The fluid-structure coupling velocity field calculates the heat dissipation coefficient of 139.9 W/(m2*k). The highest temperature is 107.53°C at the heat source copper plate, and the lowest temperature is 69.3°C at the permanent magnet plate. It meets the requirements of industry standards, but the high temperature rise causes the magnetic field transmission performance to decline. Based on this working condition, a method of opening vent holes in the inner ring of the steel plate is proposed to improve the heat dissipation performance, and finally the maximum temperature of the copper plate is reduced by 10℃, and the remaining temperature is reduced by 4~6℃, and the temperature distribution is more uniform.