Sensorless Control Impact on Electromagnetic Vibrations and Acoustic Noises in Interior Permanent Magnet Synchronous Machines

Sensorless control techniques can save expenses while enhancing the robustness and reliability of permanent magnet synchronous motor (PMSM) driving system. High-frequency (HF) voltage injection is a practical and effective way to realize zero-low-speed sensorless control of PMSM. However, the HF injection signals can introduce new current harmonics and complicated electromagnetic force waves, resulting in substantial electromagnetic vibration and acoustic noise, which greatly limits the application of sensorless control strategies. In this article, based on the interior PMSM, the new current harmonics and electromagnetic force wave components generated by the pulsating HF signal injection sensorless control method are derived theoretically. The corresponding spatial order and frequency characteristics of electromagnetic force are obtained and verified by co-simulation model. Finally, the impacts of different operating parameters are analyzed through multiple sets of experiments of electromagnetic vibration and acoustic noise. This study is beneficial for the identification and suppression of vibration/acoustic noise for HF signal injection sensorless control strategy of PMSM.