MICRO-CONTROLLER BASED THREE PHASE CURRENT CONTROLLED PWM INVERTER FED INDUCTION MOTOR DRIVE

Abstract

The design, fabrication and performance evaluation of a micro-controller based three phase current controlled PWM Inverter fed Induction motor drive has been discussed in this dissertation. A sinusoidal pulse width modulation strategy has been realized using analog/digital circuits. The switching patterns corresponding to sinusoidal modulation technique are generated in order to control the output of the Inverter. This dissertation consists of eight chapters. The chapter-wise contents are as follows. The first chapter discusses the present status of ac, drives technology in which the salient technical features of ac machines, converters, controls, and performances of the integrated drive system have been discussed. The second chapter describes the review of literature related to current control, PWM modulation, MOSFET, and control strategy. The chapter three deals with the various pulse width modulation techniques recently used and their harmonic considerations are discussed in brief. The chapter four consists of the various current control techniques presently used and theseare discussed in detail with their advantages and draw backs. The chapter five discusses the consideration for selecting the devices for the inverter and the protection when using MOSFET in designing PWM inverter, operating at higher frequency. In chapter six complete hardware and its interfacing is discussed. Each card of the hardware Is described and Its relevant circuit is also given. In chapter seven different control scheme used in this system is discussed in detail. The control strategy with there algorithm is given in detail. The chapter eight deals with the experimental performance evaluation of the drive system. The performance of the drive system is evaluated under steady state and transient operating conditions of the drive system in open loop and closed loop conditions. In this chapter, the over all. conclusion of the developed drive system and scope for further work is also proposed. (