Electric demand management for electric vehicle charging stations as an alternative to distribution network reinforcement

Abstract

This study aims to evaluate the effectiveness of various demand management methods for residential charging stations in reducing peak demand and the extent of distribution network reinforcement needed to accommodate electric vehicle charging infrastructure. The analysis is performed for a 10‑kV distribution network supplying more than 6,000 customers. Maximum electrical loads were determined using simulations that account for the charging behavior of electric vehicle owners, charging station parameters, and the daily load profile of the distribution network. To limit the power drawn by charging stations, a delayed charging strategy was applied, as well as single‑level and two‑level direct demand control schemes. For each demand management method, the resulting load profiles of both electric vehicle charging stations and the distribution network were modeled. The results show that widespread electric vehicle adoption leads to a substantial increase (44 %) in peak load in low‑ and medium‑voltage distribution networks, posing a risk of equipment overload and necessitating significant investment in distribution network reinforcement (approximately 70 million RUB). The examined demand management methods reduced the network peak demand by 13 %, offering an economic benefit by lowering reinforcement costs by up to 66.94 million RUB. The average incomplete charging associated with the single‑ and two‑level control schemes was only 0.93-1.55 %. Overall, demand management for electric vehicle charging stations can significantly reduce the cost of distribution network reinforcement while having only a minor impact on the charging quality of electric vehicles.