INVERTER DESIGN FOR ELECTROMAGNETIC STIRRER

Abstract

Modelling and simulations of power converter circuits have been 'an enormous aid in forecasting circuit performance and improving cycle time from circuit design to manufacturing by eliminating most of the prototype iterative testing needed. Pulse Width Modulation variable speed drives are increasingly applied in many new industrial applications that require superior performance. Recently, developments in power electronics and semiconductor technology have led to improvements in power electronic systems. Variable voltage and frequency supply to a.c drives is obtained from a three-phase voltage source inverter. A number of Pulse width modulation (PWM) schemes are used to obtain variable voltage and frequency supply. The most widely used PWM schemes for three-phase voltage source inverters are carrier-based sinusoidal PWM and space vector PWM (SVPWM). This report presents the simulation of low frequency inverter particularly for electromagnetic stirrer application. An electromagnetic stirrer can be treated as a linear induction motor with large air-gap, in which the inductor operates as a stator and the metal liquid is like a rotor. In this work, mathematical model of linear induction motor is also presented.