Steady-State Characterization of the Three-Phase Isolated DC-DC Bidirectional Converter with LLC Resonant Tank

Abstract

This paper presents a theoretical and computational analysis of a novel three-phase DC-DC isolated bidirectional LLC resonant converter using frequency modulation to ensure the rated output voltage. The converter presents eighteen switches, three inductors and three high frequency single-phase transformers connected in open delta-wye configuration to isolation. The switching frequency preferably operates above the resonant frequency to ensure a ZVS soft switching operation. For the mathematical analysis of the converter, a single-phase model was used considering only the fundamental components and considering the main components as ideal. This converter is recommended for Energy Storage Systems (ESS) applications. Simulation results regarding a design example are realized to proof all theoretical analysis developed.