Steady-state analysis for resonant converters

A novel and general approach is proposed to analyze different types of resonant converters. In this approach, the step function is used comprehensively to represent switching information, demonstrating that the steady-state analysis of resonant converters can be correctly and precisely performed by existing methods in linear-network analysis. The proposed approach not only explicitly considers the influence of the parasitic resistor, but elucidates the physical implications of using a nonideal resonant tank. With the proposed approach, unified closed-form expressions for the voltage and the current of the resonant components can be easily found. The parallel-resonant converter operating at constant frequency is chosen as an example to show how to apply the theory to practical analysis. Analysis, simulation, and experiment are shown to agree very well.<>