An equivalently derived circuit model for zero-current-switched forward resonant converters

An equivalently derived circuit model (EDM) with the transformer T-model incorporated for generalizing and simplifying the design of zero-current-switched forward resonant power converters (forward ZCS-RC) is proposed. The modeling for the three kinds of converters, ZCS parallel-resonant-converters, ZCS quasi-resonant-converters, and ZCS primary-secondary-resonant-converters, is conducted by the state-variable approach. Using the presented EDM, the three kinds of resonant converters are analyzed in the discontinuous conduction mode. Compensator design for stabilizing the system performance is described. To verify the modeling results, a typical design example is presented and its simulated results are compared with the measured data