Assessment of the impact of electric vehicle charging on low voltage distribution system in Takoradi

This study assessed the impact of electric vehicle (EV) charging on low voltage (LV) distribution systems at different penetration levels. The existing electric power distribution system of Takoradi, the Western Regional capital city of Ghana was modelled using the power analysis software Electrical Transient and Analysis Program 2019 . Load flow analysis was then performed on the low voltage distribution system to further assess the total amount of EVs the distribution system can handle. EV charging impacts on the current LV distribution system was assessed under three different scenarios; current state, minimum and maximum uptakes penetration levels of EVs. Two different EV charger models were employed to represent home charging (HC)-7.4 kW level-2 and fast charging (FC)-50 kW level-3. Voltage variations and transformer loading at twelve substations were meticulously noted in all simulations. The load flow simulation did not show any significant impact on the distribution system at the current state and minimum uptake penetration levels. However, at a maximum penetration level of 1.88 % for HC and 1.11 % for FC, under voltage conditions were observed at most buses with the condition deteriorating to the highest penetration level of 11.63 % and 6.87 % for HC and FC respectively where the system tend to fail. Domestic loads significantly increased along with the increment of EV penetration levels over the years which contributed to total instability of Takoradi Distribution System (TDS). The study revealed that, the impact of EV charging on low voltage networks vary by factors such as vehicle density, power demand and network architecture. In effect, EV charging types, significantly impact load and voltage variables, contributing to network instability in TDS. To address these challenges, integrating renewable energy sources like solar and wind with EV charging infrastructure is recommended to promote grid stability and sustainable energy practices. The findings of this study will assist policy-makers take the appropriate actions needed to manage EV loads.