Design and Analysis of Five-level cascaded LLC Resonant Converter

Abstract

The design and analysis of a five-level cascaded LLC resonant tank converter was presented in this study. The proposed converter steps-down the voltage, and the construction of the designed converter and the tank selected parameters forces the input impedance of the resonant tank to behave as a capacitor. Besides, the lack of any transformer in this design is beneficial in terms of cost reduction and the number of elements. The performance of the proposed converter was evaluated in a MATLAB-SIMULINK platform and based on the outcome of testing three different switching frequencies and measuring the ZCS for all switches, there was an agreement between the simulation and theoretical findings. Hence, the results conformed the ability of the proposed converter to provide a wide range of load operation (0.8 ≤ Fn ≥ 1.6) with input voltage of almost 400V and output voltage of 48V.