The Research Of Induction Motor Losses And Its Thermal System For Electrical Vehicle

In the world where energy conservation, environmental protection and sustainable development are growing concerns, the development of electric vehicle (EV) technology has taken on an accelerated pace. In the EV motors, induction motors widely used for electric propulsion are principally for its merits of small volume, high efficiency, low cost, low maintenance expense, widely constant power region, and control simplicity. It is important to take researches on power loss and thermal management with different operation mode, which is meaningful to improve the efficiency of wide speed operation region and the reliability of the propulsion system.The method employing electromagnetic field to calculate the power loss of induction motor and employing thermal circuit and thermal field to calculate the temperature rise of the motor is discussed, on the basis of the research on the losses and thermal of the motor.Firstly, the electromagnetic field calculating model of EV induction is established, according to the results of FEA, the loss of the motor is obtained at different operation mode. The analyses of the ratio of all kinds of loss at different operation mode are given.Secondly, the thermal model of the induction motor is established, combining with the calculating results of electromagnetic field, the distribution of temperature field is calculated and the calculating method of mechanical, electrical and thermal integration is discussed.Finally, the experiment research is carried on the heating of the motor to validate the calculating results.This paper provides a method of design optimization, extending high efficiency region and thermal management system for EV induction motor and lays a foundation of future research.