Research on heat dissipation design method for motor controller radiator

Abstract

With the complication of electric vehicles operating conditions, the damage caused by the overheating of insulated gate bipolar transistor and freewheeling diode that are the core components of the motor controller has become a key factor restricting the development of electric vehicles. The motor controller is primarily cooled by a radiator, and the heat exchange of the radiator includes heat transfer between the heat sources of the motor controller and the radiator walls and heat convection between the cooling medium and the radiator walls. A fluid–solid coupling heat transfer model for analyzing the motor controller was established. The flow field performances and main influencing factors were analyzed, and the correctness of the method was verified by experiments. To improve the design efficiency of the motor controller radiator, a design method based on target temperature, installation position of the liquid cooling radiator, fluid parameters, and heating power was proposed. This method can quickly calculate and evaluate the heat dissipation capability of the radiator. The fluid–solid coupling heat transfer model using this design method is established in computational fluid dynamics software, and the results show that the relative error between the simulation results and the design method results is within 20%.