Research Of High-speed Brushless Permanent Magnet Motor System's Design And Control

High-speed motor has high speed, high power density, and High-speed motors'geometric dimension is much smaller than the low-speed motors at the same level of power. For these benefits, high-speed motor makes more and more attention to the industry. High-speed motor applications are increasingly widespread. Permanent-magnet brushless motor has simple structure and high efficiency, especially suitable for high-speed situations. In recent years, with the performance of rare-earth permanent magnetic materials continuously improved, costs continuously decrease, high-speed permanent magnet brushless motors are increasingly used in wider areas and lead to domestic and foreign research institutions and researchers'interests.The research of High-speed permanent-magnet brushless motor system focuses on two aspects:the design of the motor and motor control system.In the aspect of high-speed permanent magnet brushless motor design, this thesis summarized the designing methods and some of the key issues of high-speed permanent-magnet brushless motor design. This thesis also studied on the structural design of the motor, and researched the stator structure and the air-gap length on the motor Performance. According to the given design goals 7.5kW,30,000 rpm, this thesis designed a high-speed permanent magnet brushless motor and given the design list.In the aspect of high-speed permanent-magnet brushless motor system control, this thesis described the basic principles and hardware structure of high-speed permanent-magnet brushless motor control system. This thesis also researched a current control strategy which is suitable for high-speed permanent magnet brushless motor control system; Designed a high-speed rotor position and speed detection unit; Write software for achieving the high-speed permanent magnet brushless motor control method. Finally, this thesis experimented on the high-speed permanent magnet brushless motor experiment platform and given the experimental results. The Experimental results show that the control principle of the method is correct, and the method is feasible.