Hybrid resonant half-bridge DC/DC converter with wide input voltage range

Photovoltaic power conditioning systems (PCSs) requires a high-boost ratio over wide-input-range along with the isolation. This paper presents a hybrid resonant half-bridge dc/dc converter for photovoltaic power applications. This converter operates in a resonant half-bridge converter (RHBC) mode when the input voltage is higher than nominal input voltage. When the input voltage is lower than the nominal input voltage, the converter operates in a resonant boost (RB) mode in which the resonant half-bridge circuit on the secondary side boosts the secondary side resonant inductor current to achieve high boost-ratio. As a result, the proposed converter achieves high boost-ratio over wide-input-range with simple circuit structures. Detailed analysis of the converter operation is discussed along with the experiment using 600-W prototype to confirm the theoretical analysis and validity of the proposed converter.