Implementation of softswitched frequency unfolder technique for single phase inverter

In this paper, a novel DC link softswitched inverter is presented. The new inverter uses softswitched frequency unfolder technique to provide soft-switching feature while keeping pulse width modulation (PWM) capability without high voltage stress The main obstacle for inverters to operate at high frequencies is the increasing switching losses with the increasing switching frequencies. At high switching frequencies, the EMI noises in the circuitry increase and power density decreases. To overcome these problems, switching losses must be reduced. In this paper, with the help of proposed softswitching cell, the power loss at the switching instants are terminated and the operation of inverter at high frequencies ensured. As a result, with the use of the unfolder technique and softswitching cell, inverter efficiency increased.