Simulation of Four Switch PWM AC Chopper Fed Single Phase Induction Motor

Abstract

To improve the performance of motor drives, there is a need to improve the quality and reliability of the drive system. With the high power handling capability of IGBT, pulse width modulated AC chopper can be used in high power applications. AC chopper using pulse width modulation provides substantial advantages over conventional line commutated AC controllers. To alleviate the problems associated with the conventional AC voltage controllers, pulse width modulated AC chopper fed induction motor drive is developed and presented in this paper with an appropriate control circuit. FFT analysis for voltage and current is performed for the developed system. The harmonics are reduced by using LC filter at the output. It is proved that total harmonic distortion obtained from the developed circuit is less than that of phase controlled AC chopper system. Simulation results closely agree with the analytical predictions.