Normalized Analysis and Optimal Design of DCM-LCC Resonant Converter for High-Voltage Power Supply

According to the critical conduction mode (CRM), a normalized steady-state model of the LCC resonant converter, in terms of the parallel-to-series resonant capacitor ratio and the output gain of the resonant tank operating in CRM, is presented, which can serve to infer the dynamic characteristics of the resonant tank. Depending on the two resonant parameters in the established model, this article analyses the parameter optimal design of the resonant components operating in discontinuous current mode (DCM), which is helpful to improve the utilization of the resonant current, reduce the electrical stresses of the resonant tank, and optimize the efficiency of the power supply. The ultimate purpose of this article is to derive an optimal design method for the DCM-LCC resonant converter, which could optimize the operating state of the resonant converter. Two high-voltage power supply prototypes are used to justify the established model, and the experimental results are in good agreement with the model analysis, which verifies the correctness of the optimal design.