Audible noise reduction method in IPMSM position sensorless control based on high-frequency current injection

Methods for sensorless control involving the injection of a high-frequency signal in the low-speed range of the Interior Permanent Magnet Synchronous Motor (IPMSM) have been proposed. However, audible noise is a concern in these methods. We propose a method to reduce the audible noise due to a high-frequency current by minimizing the injection signal amplitude suitable for IPMSM driving states.