Novel sensorless state feedback speed control technique of IPMSM drives

In this paper, a new sensorless control technique of Interior Permanent Magnet Synchronous Motor (IPMSM) drives is presented. This control technique employs state feedback control theory. An optimal gain matrix is obtained using linear quadratic regulator. A new linearization approach which is the most important idea of this paper is developed based on quadratic linearization method to linearize the nonlinear state equation of the IPMSM. This control technique controls IPMSM in whole speed range using maximum torque per ampere control strategy and voltage constraint tracking control strategy. A model reference adaptive system based speed estimator is employed instead of mechanical speed sensors to eliminate the problems of these sensors. MATLAB/SIMULINK software is used for simulation and verification of the presented theory.