Capacitive Coupling for High Voltage Ratio Power Transfer in Multi-Cell Converters Based on GaN HFETs
Résumé
A multi-converter architecture for high-transformation conversion ratio based on Dual Active Bridge converters is presented as good candidate with high integration capability, bidirectional power flow and soft switching (ZVS) operation. The paper analyses and describes the impact of galvanic isolation in DC-DC conversion systems on losses and integration. Based on conclusions, a non-isolated multi converter approach is developed and analysed for medium voltage applications. It is based on an effective capacitive coupling of DAB converters implemented in a modular approach. Simulation results on Dual Active Bridge Capacitive coupling (DAB-C) are supported by experimental results from a 150 W, 30 V / 5 A input on DAB-C prototype operating at 1 MHz switching frequency implemented with GaN HFETs components.