Multi-port converter for solar powered hybrid vehicle

Abstract

In this paper a novel Multi-port converter interfacing a photovoltaic array, battery and a DC load is proposed It is composed of a two uni-directional DC port for interfacing photovoltaic array and DC load, and a bi-directional DC port for interfacing battery. Compared to the traditional stand-alone photovoltaic power system, this system shows the advantages of better protection and more efficient control on charge/discharge of the battery. Furthermore, it can make better use of solar energy and realize energy management of the system The key point of energy management for the system is to control the bi-directional converter efficiently, where bi-directional voltage and current must be controlled. In this paper, the control strategy of bi-directional converter is proposed, which operates at three operation modes: Buck (charge battery), Boost (discharge battery), and shut-down (SD). Maximum power point tracking control is used to extract the maximum power from the Photovoltaic array. Single power processing stage with multiple power ports offers an opportunity to make the whole system simpler, compact and more efficient. Finally, a simulation of 250 W and 5 hp converter is built to verify the theoretical analysis and the control strategies. The simulation is tested for variable irradiance and variable load.