A Single-Stage ZCS Boost Module for MVDC Collection Converters

To accomplish the large-scale renewable energy collection to the medium-voltage dc grid within one single stage, an interleaved current-fed zero-current-switching (ZCS) boost module for input-parallel-output-series dc-dc converter is proposed in this article. In the proposed module, two interleaved current-fed arms are responsible to achieve a high step-up ratio, while two reverse series switches in the resonant tank path are employed to regulate the equivalent duty cycle. The full ZCS in the whole load range is achieved for all the semiconductors. The operation principles and parameters design are analyzed in detail. Finally, all theoretical analysis and characteristics are verified on a 30-70 V/600 V/1 kW prototype.