Speed sensorless electric vehicle propulsion system using DTC IM drive

This paper describes a control scheme of speed sensorless direct torque control (DTC) of induction motor for electric vehicle (EV). Electric vehicle requires fast torque response and high efficiency of the drive. Speed sensorless DTC induction motor drives without mechanical speed sensors at the motor shaft have the attractions of low cost, quick response and high reliability in electric vehicle application. To replace the sensor, the rotor speed is estimated from sensed stator voltages and currents at the motor terminal. This control strategy is extensively used in electric vehicle application. Modelling and simulation is carried out in standard MATLAB/SIMULINK software. The drive performance is studied for acceleration, braking and flux weakening (above rated speed). The obtained results demonstrate the comparison of performance characteristics of the both the scheme.