Multiport DC-DC Converter for Integrating Energy Systems in All-Electric Vehicles

In this paper, a new non-isolated multiport dc-dc converter (MPC) of non-inverting buck-boost configuration is proposed for integrating multiple energy resources in automotive applications. A typical example of such automotive application is an electric vehicle (EV), powered by one or more renewable energy sources (RESs) and consisting of one or more energy storage systems (ESSs), e.g. batteries and supercapacitors. The inputs to the MPC are clustered based on source or storage and integrated using uni- or bi-directional switches, respectively. It is capable of bi-directional operation between the storage cluster and the dc link, allowing for a simultaneous transfer of energy from more than one source of varying voltage levels (irrespective of its' cluster) to the dc link. The proposed MPC is analysed for four inputs, comprising of two per cluster in this paper. As compared to existing MPCs in literature, the proposed converter utilizes a fixed number (two) of inductors and is robust such that it requires only one additional switch to integrate any extra energy storage or source in a respective cluster. Different operating modes of the proposed MIC are numerically verified and validated on OPAL-RT's OP5700 hardware-in-the-loop (HIL) platform.