Isolated Boost Converters

Two implementations of the isolated boost converter that exhibit no parasitic voltage ringing across all semiconductor devices on the primary and secondary sides of the transformer are introduced. Ringing-free operation is achieved by clamping the voltages of the primary switches and rectifiers to the voltage of the primary-side energy-storage capacitor and clamping the voltage across the secondary-side rectifiers to the output filter capacitor. The performance of the proposed topology was verified on a dual ac-input, 900-W experimental prototype operating at 67 kHz.