변압기의 가변 턴비 기법을 통해 넓은 전압범위를 만족하는 리튬이온 배터리용 고효율 LLC 공진형 컨버터

Abstract

In this paper, the LLC resonant converter battery charger, using adaptive turn ratio scheme, is proposed to achieve high efficiency and wide range output voltage. The LLC converter high frequency transformer has an adaptively changed turn ratio by the auxiliary control circuitry. As a result, the optimal converter design with a large magnetizing inductance is easily achieved to minimize the conduction and the turn-off losses while providing widely regulated voltage gain capability to properly charge the Li-ion battery. The proposed converter operational principle and the optimal design considerations are illustrated in detail. Finally, several simulation results verify the proposed LLC resonant converter’s effectiveness.