Impact of Electric Vehicles on Peak Load Reduction

As electric vehicles (EVs) have being rapidly deployed into the transportation industry, they can be used for a reduction in peak load of electric power distribution systems. Therefore, the objective of this paper is to present a typical method that analyzes the effect of charging and discharging EVs on (a) a reduction in peak load, (b) an increase in under- (e.g., 0.95 PU) and over-voltage, (e.g., 1.05 PU), and (c) intermittency in voltage and total power generation. For this purpose, this paper (a) proposes a simple strategy that charges EVs at night and discharges them to the grid at peak demand hours, (b) defines a load factor and a change in total power generation from an interval to another, and (c) models a distribution system that hosts charging stations for EVs and photovoltaic (PV) systems. Then, to calculate the power flow of such a distribution system, including PV and charging systems, in steady state, this paper uses the Open Distribution Simulator (OpenDSS), a power system analysis computer program useful for calculating the power flow of electric power systems. Finally, it analyzes the effect of charging and discharging EVs on a distribution system.