Analysis of Resonant PWM Active-clamp Cuk DC/DC Converter

In this paper, a novel steady-state modeling technique is introduced for resonant pulse width modulation (PWM) active-clamp (PAC)-Cuk dc/dc converters. The PAC-Cuk dc/dc converter is equipped with two clamping circuits which enable ZVS turn-on of all the switches resulting in high-efficiency operation of the converter. A resonant form of PAC-Cuk dc/dc converter is introduced and studied using the modeling technique to develop the output power and series inductor current dependency on the control parameters. As the resonance introduces high nonlinearity in the analysis, the traditional steady-state modeling generates erroneous results. Hence, a closed-form LC resonant modeling technique developed in this paper is used to analyze the impact of resonance on the PAC-Cuk dc/dc converter. The resonant model is developed using the superimposition and state-plane trajectory technique. The developed resonant modeling technique delivers an exact solution for a resonant LC link connected across two active voltage sources which applies to other resonant converters.