DC-Shifted Harmonics-Boosted Resonant DC-DC Converter with High-Step-Up Conversion Ratio with ZVS Over the Full Load Range

In this paper, a single-switch DC-shifted harmonics-boosted resonant DC-DC converter topology that can achieve a high-step-up conversion ratio is proposed. In addition to the fundamental resonant component, this converter utilizes the high-order harmonic components and DC component to further increase the actual achievable voltage gain of the resonant converter. The operating principle and design of the proposed converter are presented. It is illustrated that with proper design, the proposed converter can attain a fairly constant conversion ratio (around 12.8% variance) and can maintain zero voltage switching (ZVS) operation for load ranging from no load to full load. A 500 kHz, 35 V input, 380 V output at 280 W prototype is constructed and tested. Experimental results are provided to illustrate the various properties of the proposed converter: low voltage stress, high dc voltage gain, soft switching operation, continuous input current, and line-load common ground.