Position Sensorless Control for IPMSM Based on Extended EMF and Voltage Injection Synchronized with PWM Carrier

Abstract

This paper presents a new position sensorless control system for an interior permanent magnet synchronous motor (IPMSM). The proposed method is based on the extended electromotive force (EMF) and voltage injection synchronized with a pulse-width modulation (PWM) carrier. The proposed method does not need to switch the estimation method by speed in order to estimate the magnetic pole position by extended EMF, even at low speeds. Further, the amplitude of the superimposing voltage is changed according to the extended EMF; the applied voltage is not saturated in the high-load and high-speed regions. The effectiveness of the proposed sensorless control system was verified experimentally.