Steady-state analysis of zero-voltage switching primary capacitor coupled converter

The operation and steady-state analysis for zero-voltage-switching (ZVS) primary capacitor coupled converter topology are presented in this paper. ZVS and proper transformer reset can be achieved through the resonance that exists between the transformer magnetizing inductance and the parasitic capacitance of switches. The steady-state analysis will be given to illustrate the principle of operation. A 100kHz, l40V input prototype converter was implemented to show that the experimental results are in good agreement with our theoretical analysis. By using the presented topology, the voltage stresses across the switches are limited to the input voltage. The voltage stresses across the switches are greatly lower than the converters with active -clamp circuit.