Experimental performance analysis of adaptive flux and speed observers for direct torque control of sensorless induction motor drives

Abstract

One of the most important issues in implementing direct torque control (DTC) of sensorless induction motor drives is to obtain accurate information about stator flux level and position for the entire speed range. This paper presents experimental performance analysis of an adaptive stator flux and speed observer with stator resistance tuning, performed by a DSP controller. The analysis focuses both on transient and static characteristics in association with two DTC strategies: basic DTC and discrete space vector modulation DTC (DSVM-DTC).