MODELLING AND ANALYSIS OF CSI FED DRIVE USING FIELD ORIENTATION CONTROL

Abstract

The control and estimation of A.0 drives in general are considerably more complex than those of dc drives, and this complexity increases substantially if high performances are demanded. The main reasons for this complexity are the need of variable frequency, harmonically optimum converter power supplies, the complex dynamics of ac machines, machine parameter variations and difficulties in processing feed back signals in the presence of harmonics. With the advancements of power electronics, digital signal processor technology and different control strategies, a.c drives becomes more efficient. Especially, indirect vector control strategy which has been using for induction machines makes the induction machine more popular in industries now days. This control strategy allows high performance to be achieved from an induction motor. Vector control or field-oriented control is the first method that enables the application of a linear strategy for the torque control of an induction motor. A computer control makes control strategies simple. Entire control part is implemented through programming., ow-ever it requires some peripherals like. 8255, 8253 and 8259 interrupt'-set. The present work presents modeling and simulation of CSI fed induction motor drive using indirect field oriented control using Matlab/Simulink. The mathematical modeling takes into account the rectifier, inverter and induction motor dynamics and is established in stationary reference frame. The hardware setup and implementation of speed control of induction motor through computer also presented. iii