A salient-pole PMSM position and speed estimation at standstill and low speed by a simplified HF injection method

Abstract : This paper addresses the estimation of a permanent magnet synchronous machine mechanical position and speed estimation at low speed and standstill. The method is based on the injection of an additive voltage at High Frequency (HF), which exploits the position dependency to the magnetic saliency. Unlike the usual HFI method, this estimator has a simple structure with only one filter. The simulation results prove the efficacy of the estimation under no load and with a load torque in the low speed region and at standstill. The mechanical position estimation errors are lower than 0.035rad (2°).