A Zero and Low Speed Sensorless PMSM Drive Utilizing Existing Inverter PWM harmonics

A novel position sensorless Permanent Magnet Synchronous Motor drive is proposed in this paper. The presented method is intended for the operation of PMSMs with magnetic rotor saliency. The novelty of this research is the development of a method that makes use of high frequency signals, intrinsically present in a PWM voltage source inverter drive system, for detecting the machine impedance saliency. The final target is to use this information in order to reconstruct the rotor position. No additional signal injection is applied, only the inherit present high frequency signals (PWM carrier harmonics) are used.