Soft switched auxiliary resonant circuit based boost converter with reduced stress using ZVT PWM

摘要

The stress across the switch and the ripples in the output voltages in a Boost converter can be decreased with the help of soft switching. This paper proposes a soft switched auxiliary resonant circuit to provide a zero voltage transition (ZVT) turn on for the main switch in a conventional pulse width modulated boost converter. The proposed auxiliary circuit will enable the main switch to be turned on exactly or near to ZVT. The auxiliary circuit consists of an auxiliary switch which is also turned on by ZVT. The PWM boost converter causes voltage stress across the switches when turned on under non zero voltage turn on process. This voltage stress can be reduced by turning on the switch under ZVT. Moreover, the circuit has been designed to provide proper gating signals for the switches. Also the passive components involved in this circuit are designed for the reduction of voltage ripples that appears across the output voltage. Detailed operation and the circuit waveforms are theoretically explained. To verify the effectiveness of the proposed circuit, the simulation is done using PSIM software.