A piece-wise linear model of a Zero-Voltage Transition DC-DC Converter

Formulation to obtain a piece-wise large-signal model of a Zero-Voltage Transition PWM Converter is presented in this paper. This circuit integrates the transformer leakage inductance and the output capacitance of the power switching devices into the converter operation principle, which results in a suitable strategy to build a high-frequency compact DC-DC converter with fixed-frequency, phase-shift control. The principle of operation of the converter and a piece-wise linear analysis are described together with a derivation of a large-signal model of the ZVT circuit. The piece-wise large-signal model is then verified with simulation and experimental result obtained with a 250W prototype.