Reliability research of DC charging module

LLC resonant converter is most frequently effective DC/DC converter to improve the power density and efficiency of DC charging module in electric vehicle power supply. Soft-switching technique can be applied in the topology to reduce the switch losses. However, DC charging module brings about 27% of failures in Electric vehicles (EV) charge device. The aim of this paper is to evaluate the reliability of a 3.8 kW LLC resonant converter as DC charging module in both component level and system level. The power losses of mainly power components are deduced and the thermal model together with the lifetime model are built to evaluate the reliability of the LLC resonant converter in component level. The converter level reliability is obtained by the component level reliability, Weibull distribution and Reliability Block Diagram (RBD).