Permanent Magnetic Synchronous Motor and drives applied on a mid-size hybrid electric car

Abstract

Electric machine and drives are key parts of hybrid electric vehicle (HEV) power train. Demands for electric machines and drives are different. In general, such characteristics as large torque, high rotation speed, high power density, quick response, good reliability and electromagnetic compatibility (EMC) are demanded of. A Permanent Magnet Synchronous Motor and drive are developed and applied on a mid-size hybrid electric car. There are two electric machines in this electric car. One is coupled with internal combustion engine (ICE) by belt as integrated starter and generator (ISG), and the other is coupled with driving wheel through final gears as main motor. Both electric machines are Permanent Magnet Synchronous Motor. Design and analysis of main motor and drive are presented in the paper. Under the hybrid power train control strategy, the torque-speed curve of electric machine is determined by simulating the operating points of electric machine under certain drive cycle. Electric machines are integrated with ICE and transmission which decreases the space occupying of the power train. The type motor and drive system with CAN bus communication with vehicle control unit are developed. Torque control and flux weaken control satisfy the demands of the power train control strategy, as well as maximum efficiency control optimizes the efficiency of whole power train. Torque-speed curves and motor drive efficiency map are presented experimental research. The experiment results show that Permanent Magnet Synchronous Motor Drive System is well applied in a mid-size hybrid electric car.