Speed sensorless direct torque control of a PMSM drive based type-2 fuzzy logic stator resistance estimator and luenberger observer

Abstract

Direct Torque Control (DTC) has its drawbacks, which include high torque ripples, the need of the rotor shaft position and the variation of the stator resistance, which seriously affects the estimation of the stator flux necessary for the implementation of this control. To overcome these drawbacks, Luenberger observer is used to estimate speed and rotor position associated with Fuzzy Logic Resistance stator compensator used to eliminate the effects of parameter variation (stator resistance variation introduced errors in flux and torque estimation and affect seriously the DTC performance). In Other hand, in order to improve this control strategy, we propose: an estimator based on type-2 fuzzy logic controller (FLC) to resolve the problem of parametric variation which is more required than the type-1 fuzzy logic controller.