关键词: 永磁同步风机, 单电阻, 带速重投, 流频比控制, 切换

Abstract: Affected by wind, the fan will start in rotating condition. The traditional method cannot sense the motor current with single shunt in zero vector. To solve this problem,the active zero state pulse width modulation(AZSPWM) is adopted to reconstruct the phase current. The motor speed, rotation direction and rotor position are calculated. I/f with frequence modify and optimized transition method are adopted. The fan can start in wide speed range. The effectiveness of the proposed method has been verified by experimental results. The results show that the fan can start in rotaing condition with the speed of -800 r / min to 800 r / min.

Key words: PMSM fan, single shunt, start in rotating condition, I/f, transition