Computer Simulation of SPWM-VSI for Minimizing the starting torque and current in Asynchronous Motor Drive

The paper involves the speed control of three phase induction motor by using the PWM fed VSI. Speed can regulate by varying the external resistance in series with rotor circuit but this method is not so efficient. Therefore this paper is focused on frequency control method for which a three phase induction motor drive fed by Pulse width modulation Voltage source inverter. PWM is most reliable and efficient way to regulate the output voltage of VSI. There are several ways to modulate the pulse width but this paper deals with sinusoidal pulse width modulation technique. By varying the modulation index of SPWM then vary the voltage of VSI. This technique minimizes the lower order harmonics and improves the response of VSI. The transient rotor current, electromagnetic torque and rotor speed of the Induction Motor will improve. Proposed model of open loop PWM Inverter fed induction motor drives in MATLAB/Simulink software.