ANALYSIS, DESIGN AND SIMULATION OF AN IMPROVED ZVS – PWM,

Abstract

The objective of the work presented in this report is to develop an improved ZVS–PWM, active clamp/reset forward converter. Then proved active clamp forward uses one extra clamping diode and a resonant capacitor, the additional clamping diode limits the voltage stress on the rectifier diode. Soft switching is obtained for active and passive switches. Based in the proposed topology, a prototype is designed and simulated using MATLAB. All waveforms are in agreement with the theoretical waveforms. Only pole voltage is observed to have some ringing. The ZVS-PWM, active clamp/reset power converter rated 30 watt, 280 KHZ achieves efficiency close to 90%. A new approach to investigate the sub harmonic oscillation in current program, ZVS-PWM, active clamp converter is presented. The proposed approach correctly predicts the stability or otherwise of the current programmed active clamp converters. It is observed that the family of active clamp converters also exhibits sub harmonics oscillations...