A Two-mode Resonant DC-DC Converter for Small-scale Wind Power Generation Systems

A two-mode resonant DC-DC converter is proposed in this paper. Through controlling the on/off state of the auxiliary switch, it can be flexibly converted between LLC mode and LLCC mode. In particular, the proposed converter works in LLC mode near the rated point. As the input voltage rises, it operates as an LLCC converter to acquire wide voltage gain range and over-current protection. The detailed characteristic comparisons are discussed, thus the optimal switching point is determined. Finally, experimental results demonstrate the rationality of the theoretical analysis.