Y결선 정류기를 이용한 3상 인터리브드 LLC 공진형 컨버터의 출력 전류 리플 밸런싱 방법에 대한 연구

Abstract

This paper proposes the output current ripple balancing method for three phase interleaved full-bridge LLC resonant converter using a Y-connection rectifier. The above-mentioned converter has various advantages. By using a Y-connection rectifier, the turn ratio of the transformer is four times less than that needed for a conventional LLC resonant converter using center-tapped secondary windings while still regulating at the same output voltage. In addition, there are significant reductions in the output current ripple and the required output filter capacitance. Therefore, the above-mentioned converter topology is applicable to high power and high voltage output applications. However, resonant components’ tolerance in each primary stage of the topology may cause the unbalance problem of output current ripple. Furthermore, the unbalance problem of output current ripple may decrease that converter’s advantage such as reduced output filter capacitance. To solve the problem, the paper proposes a new output current ripple balancing method. Also, the good performance of the proposed method is verified using a 10 [kW] prototype converter.