EMI evaluation in hard switching and soft switching PWM flyback converters

Electromagnetic interference generally exists in all electrical and electronic equipment, especially in switching converters. Since the switching frequency applied in switching converter is high it can causes significant EMI. An experimental comparison of the EMI profiles of two flyback converters, operating under hard switching and soft switching is provided in this paper. Results indicate that EMI emission can be substantially reduced by using soft-switching technique in power converters.