Effect of Penetration Levels for Vehicle-to-Grid Integration on a Power Distribution Network

With the exponential growth of electric vehicle sales worldwide over the past years and progress in technology and actions to combat climate change by reducing greenhouse gas emissions, the trend is expected to continue with a significant increase in the deployment of electric vehicles and plug-in hybrids. Given these circumstances, it is essential to identify the constraints that this increase in the number of electric vehicle charging stations poses for the electricity system. Therefore, the analysis developed in this paper discusses the effect of integrating electric vehicle charging stations in a real distribution network with different penetration levels. For this purpose, a typical electric system in Greece, managed by the Greek distribution system operator (HEDNO), is modeled and simulated in DIgSILENT PowerFactory software, one of the most widely used simulation tools in the electricity sector. To study the feasibility of connecting electric vehicle charging stations to the network, different case studies are presented, showing changes in the quantity of electric vehicles feeding power into the network through vehicle-to-grid technology. Quasi-dynamic simulations are used to analyze and discuss the voltage profiles of the system nodes, active power flows with the external source and power losses of the distribution network to determine whether the system is capable of supporting the increase in load produced by the electric vehicle charging stations and to promote awareness of the benefits of implementing vehicle-to-grid connections.