Brushless DC motor has simple structure, great power density, torque output and high efficiency. It has a broad application prospect for electric vehicle. The conventional scheme of BLDCM drive system adopts motor ontology, power drive circuits and position sensor. BLDCM is usually used with the mode of 3-phase 6-state PWM. Due to its structure and commutation strategy, it has many problems to be solved if works on electric vehicle. The basic operating principle of Brushless DC motor and the basic power drive system was discussed. In addition, investigated the torque ripple, flux-weakening speed control and brake energy regeneration for electric vehicle. Solving these problems can promote BLDCM and electric vehicle industry.
