Sensorless Control of PMSM Based on Active Flux Observer and MRAS Stator Resistance Identification

This paper introduces a robust sensorless control system for permanent magnet synchronous motor (PMSM) drives using the active flux observer with serial combined PMSM voltage and current models. To assure system robustness, the stator resistance identification is proposed using a MRAS with the stator current angle error in adaptation mechanism. The extensive simulation results prove the effectiveness of the proposed sensorless control system with very good steady state and dynamic performance in large speed range 1:50, with minimum speed of 20 rpm (2% rated speed) and 1°max rotor position error, for step speed and rated torque references, step speed reversal at lower speed, and linear variation of stator resistance.