High-Efficiency Regulation Method for a Zero-Current and Zero-Voltage Current-Fed Push–Pull Converter

A new high-efficiency regulation method for a zero-current and zero-voltage current-fed push-pull converter is presented. The method proposed is based on the use of a controlled transformer as a post-regulator, which adds or subtracts an additional voltage to the output filter of the converter. An auxiliary regulator, which only handles a percentage of the output power, controls this transformer, and therefore, results in much higher efficiency than a normal preregulator would have. The novelty of the presented converter is that regulation is achieved without affecting the zero-voltage and zero-current switching in any working conditions. Small- and large-signal models of the converter have been developed and a low-power prototype has been simulated and implemented. The good agreement, between the experimental simulations and theoretical results, validates the theoretical developments.