OPEN LOOP &CLOSED LOOP VECTOR CONTROL of VFD THREE PHASE VERSION INDUCTION MOTOR DRIVES

Abstract

In this paper, a design of a vector control algorithm for a three-phase induction motor. The three phase AC induction motors are a popular in manufacturing industries as it has many benefits. It is quite simple and minimum cost is favourable, it does not have brushes and requires minimum maintenance. In order to achieve variable speed operations in a three-phase AC induction motor by open and closed loop vector control technique to improve the motor’s performance, is used because this technique has higher efficiency, accurate control of the motor’s speed and torque. To analyse vector control, by converting the three phase Quantities into 2-axes system called the d- q transformation. The d-q axes can be chosen to be stationary or rotating. MATLAB/ SIMULINK is used as tool to simulate the model of (IM) and applying the control technique on it. In open and closed loop vector control, by use of PWM inverter, voltage supply can vary as well as the supply frequency such that the ratio v/f remains constant so that the flux remains constant as well.