An online parameter identification method is proposed for sensorless control for surface and interior permanent-magnet synchronous motors (SPMSMs and IPMSMs, respectively). As this method does not use rotor position or velocity to identify motor parameters, the identified parameters are not affected by position estimation error under sensorless control. The proposed method that is based on system identification theory can be applied to all kinds of synchronous motors. The effectiveness of the proposed method was verified by experiments in both SPMSMs and IPMSMs.

Keywords: Extended electromotive force (EEMF), Online parameter identification, Permanent-magnet synchronous motor (PMSM), Sensorless control