A new ZVT high step-down WCCI converter with low output current ripple

Abstract

In this paper, an interleaved step-down converter with zero voltage switching for the switches and low output current ripple is presented. Two ferrite cores with three windings are used in the proposed converter to reduce the voltage gain and the output current ripple. Therefore, the volume of the circuit does not change significantly. According to the structure of the proposed converter and the use of the ripple cancellation technique, the ripple of the output current is not high despite the use of coupled inductors. The auxiliary switch is also turned on under ZC condition and turned off under ZVZC condition. Therefore, the auxiliary circuit does not impose significant losses on the converter. To prove the correctness of the theoretical analyzes of the proposed converter, a 160W prototype has been implemented. The practical results show 95% efficiency at full load and 0.2A ripple in the output current.