Electric Vehicle Induction Motor DSVM-DTC with Torque Ripple Minimization

This paper presents a sensorless DSVM-DTC of an induction motor that propels an electrical vehicle or a hybrid one. The drive uses an adaptive flux observer for speed estimation and a discrete space vector modulation direct torque control (DSVM-DTC) technique for torque and stator flux control. The adaptive flux observer uses a mechanical model to improve the behavior during speed transients. The estimated stator flux of the adaptive observer is used in the DSVM-DTC method to provide fast torque response combined with torque ripple free operation over the whole speed range. The sensorless drive system is capable of working from very low speed to high speed and exhibits good dynamic and steady-stale performance. The combination of the adaptive observer and DSVM-DTC are quite effective in reducing the switching loss and torque ripples of the motor, as demonstrated in experimental results. Copyright (C) 2009 Praise Worthy Prize S.r.l. - All rights reserved.