A High-efficiency DC/DC Converter with SiC Devices and LLC topology for Charging Electric Vehicles

摘要

Electric Vehicles (EVs) have developed fastly supported by governments to relieve pollution issues and energy crisis in recent years. However, with the continuous development of EVs, efficient and rapid charging will restrict its further development. So a kind of charging module which owns high-output power and high-efficiency is a feasible key to solve the charging problem. However, conventional charging modules with using Silicon (Si) devices couldn't realize very high efficiency, as a lot of power losses caused by power semiconductors and magnetic devices. So reducing power loss of these devices is a useful way to realize very high efficiency. Hence, this paper plans to design a 15kW DC/DC converter with LLC topology and Silicon-Carbide (SiC) devices to reduce power loss and verify its high efficiency. The proposed converter could reach about 98.4% and higher about 3% than conventional converter at rated full-load condition. Power density and volume of this proposed converter increases 27.6% and decreases 21.9% than conventional converter, respectively. Other detailed comparison information about this two converters shown as Part-D of section-II in this paper. In the end, relative experimental waveforms used to verify the correctness and rationality of design.