Applied modelling and analysis to investigate the potential of a 11kV networked site to accommodate EV charging infrastructure

Electric Vehicle (EV) charging infrastructure will be deployed extensively in the near future. This will be as a consequence of the policies approved by the governments of many countries including the UK. The rise in the mass production of EVs and the associated increase in consumer demand significantly exacerbate the problems associated with the operation and management of future electric power networks. The 11/0.433kV local substations that will be used to transform voltage levels and supply the demand from consumers are the most affected, requiring reinforcement where substations are close to their firm capacities. In this paper an 11kV power distribution network is modelled using the power system analysis software Electrical Transient Analyzer Program (ETAP). The peak load values over a year are evaluated under four different Electric Vehicle (EV) penetration levels and three different charging types (slow, fast and rapid) at all twenty substations on site. Transformer loading at twenty substations is carefully observed in all simulations under different scenarios to evaluate the total number of EVs the site can accommodate. Initially ETAP 12.0.0 is employed to conduct power flow analysis and study the existing network conditions and later the voltage variations, real and reactive power changes in the system due to the uptake of EVs. The existing network data as required for the research and as presented in this paper has been obtained in collaboration with distribution network operator (DNO) Scottish and Southern Energy (SSE).