Small signal analysis of parallel resonant converters

The small signal analysis of the conventional parallel resonant converter (PRC), operating in the continuous conduction mode, is presented. This analysis is based on the state-plane diagram approach that has been successfully applied to the steady-state analysis of resonant converters. Using the perturbation method on the steady-state trajectory, a discrete small signal model for the converter can be derived from the input voltage, controlled switching frequency, and state variable perturbations. It can be shown that this method of analysis can be applied to resonant converters in general. Using the derived small signal model, the frequency response of the PRC can be calculated. Simulated and experimental results verify the theoretical approach