Integrated Three-Port Converter for Solar-Charged Electric Vehicle Applications

Adding onboard solar generation to electric vehicles (EVs) is one way to help reduce their charging needs andor increase their driving range. To maximize the potential benefit, differential power processing (DPP) converters can be implemented to maximize solar energy capture in partial shading conditions. Furthermore, an isolated high step-up converter is required to transfer solar energy to the high-voltage battery, and a buck converter is useful to create an efficient direct path from the solar cells to the low-voltage accessory bus. If implementing these power electronic requirements with separate converters, the component count is high and power density can suffer. Thus, this article proposes the first multiport converter with solar DPP, an isolated high-voltage output port, and a low-voltage port, which is uniquely suited for solar-charged EVs. The switch count is low, and a simple control strategy is proposed to allow separate control of the two output ports. A 200-W experimental prototype is built and tested and shows a peak efficiency of 96.7 when solar power is flowing to both the high-voltage and low-voltage ports.