AC, DC, BLDC Motor Drives
Technical Lecture Session
Permanent Magnet Synchronous Motor Drives and Control Strategies
rotor positioning, permanent magnet synchronous motor, rotary transformer, the three-phase six-state control
Because of the mismatch between poles of permanent magnet synchronous motor (PMSM) and rotating transformer, the PMSM is difficult to start smoothly. Under this condition, the motor's zero position is not unique and the detection is not accurate. A method of measuring rotor position is proposed to solve this problem. Taking the three-phase six-state control as example, a series of sets of angle data are pre-measured in sequence at different position and different rotating speed. Before the motor start, the rotor is fixed to a given position, which is included in the pre-measured data. Then the accurate angle of the rotor is defined. By the proposed method, the motor can start smoothly, as well as the accuracy and the fluctuation of angle data obtained will be improved. Therefore the stability of the system can be enhanced which will meet the high requirement of PMSM system because of the simplified control system. The correctness of the analysis is verified by the experiment.