Expanding the Operating Speed Range of Model-Based Sensorless Control for IPMSMs

A sensorless control technique for improving the performance IPMSM control such as the operating speed range and position estimation accuracy is proposed herein. The method presented is based on the estimation of an extended EMF in a rotating reference frame. The difference between the reference voltage and the actual voltage of the inverter is modeled and compensated for in order to improve the accuracy and the stability of the sensorless drive system. Moreover, an on-line parameter identification technique is applied in order to improve the accuracy of position estimation. The effects of the proposed scheme are evaluated by the experimental results.