Optimal EV charging and discharging control considering dynamic pricing

EV penetration allows the bidirectional power flow between power grid and EV, called vehicle-to-grid (V2G). The V2G implementation requires different price signals, such as real-time pricing (RTP) and time-of-use pricing (TOU). This work investigates the smart EVs charging control problem at a distribution transformer level. In order to evaluate the peak shaving and the transformer load factor increasing due to coordinated V2G process, three EV penetration levels are evaluated: 30%, 60% and 100% of residential households with one EV. The charging and discharging of the battery is optimized to minimize the net electricity cost during a 24-hour period, with three different types of dynamic prices. The computational model was developed using the Matlab/Simulink and a linear programming technique is used. The results shows that coordinated charging control limits the peak demand elevation and provide peak shaving for substation and distribution transformers. The instantaneous RTP showed better results and TOU could shift the demand peak to another time of the day.