Analytical Modeling and Optimization of LCC Resonant Converter in CCM Based on State Plane Analysis

LCC resonant converter is widely used in high voltage and high power applications. In this paper, an analytical model based on state plane analysis is proposed, which can be used to describe the steady-state characteristics of LCC resonant converter in continuous current mode. The relationship between the output voltage and the average output current of the converter is derived according to the state trajectory. The complex resonance process caused by the parallel capacitor is unified into a single state plane. The model built by state plane analysis is accurate, which helps to control and optimize the converter. Based on this model, the resonant parameters were designed to make the converter operate at minimum peak resonant current and reduce the current stress on switches. The model and optimization method are validated by simulation and experiment.