Design of induction motor drive with parallel quasi-resonant converter

A parallel quasi resonant DC link converter for induction motor drive application is analyzed and designed. The proposed soft-switching inverter is formed from the traditional pulse-width modulated (PWM) inverter by simply augmenting with auxiliary resonant circuits, and the soft switching is achieved through applying PWM switching control signals with suitable delays for the switches. The designed soft-switching inverter is used for powering an induction motor drive which is connected to drive the constant nominal load. The converter is designed to achieve the maximum voltage gradient and simultaneously to have low peak current and voltage stresses on the devices and thereby to reduce the losses.