Improved rotor position estimation of salient-pole PMSM using high frequency carrier signal injection

This paper presents a new rotor position estimator for salient-pole permanent magnet synchronous machines (PMSM) based on carrier signal injection. This method first uses a new way to extract the negative frequency component of the current, which contains the rotor position information. Compared to the classical approach, this method uses only one filter. It also performs an on line compensation of the phase shift of the filter used for this extraction. This method is used for sensorless field-oriented control, confirming then its effectiveness under various operating conditions.