3-Bridge LLC DC-DC Converter with Notch Filter for Wide Output Voltage Control

This paper introduces a novel 3-bridge LLC-LC DC-DC converter, which incorporates notch filters consisting of LC parallel resonant circuit, enabling the reduction of output voltage to 0 V
DC
. Despite an increased magnetizing inductance, the design allows operating mode switching within a narrow switching frequency range, ensuring a stable response across a wide output voltage control range. The proposed converter also can minimize excessive parallel resonant tank current by applying only a quarter of the input link voltage to the LC parallel resonant circuit, even operating at the maximum switching frequency. In this paper, we describe the operation of the proposed converter and validate its feasibility through simulations and experiments.