Modelling and design of electric vehicle charging systems that include on-site renewable energy sources

The predicted operation and performance of a 6.65 kW PV system assumed to be located in Galway, Ireland to charge 4 electric vehicles (EVs) is modeled. The performance of AC and DC distribution systems are compared. Models account for the variable efficiencies of power converter blocks as power levels vary. A control strategy is developed to choose when/how many EVs charge based on available PV power thereby maximizing efficiency and solar energy usage in the EVs. It is shown that for an EV user with a home charge point and a 100 km daily return commute, a ~90% SOC can be supported by the system during the summer months. It is also shown that the DC system is 4.67% more efficient than the AC system over the course of a year.