Impact of Electric Vehicle Charging Control on the Frequency Response: Study of the GB System

The growth of vehicle electrification is driven by the desire to reduce environmental pollution, and it is fueled by advancements in battery technology. If left unmanaged, electric vehicle (EV) charging will increase peak demand and put a strain on the electricity networks. However, if properly managed, EVs can provide useful services to the power system operator such as fast active-power injection which serves to improve the system frequency response (SFR) after a disturbance. The objective of this paper is to assess the impact that clusters of EVs, connected to frequency-responsive charging stations, have on the provision of SFR after a loss of generation event. The assessment considers EV charging demand in Great Britain (GB) for the year 2025 considering three different daily charging patterns. A generic model for the EV clusters is developed which includes the effects of measurement delays and control charger time response. The model and scenarios are integrated into a single-area model representative of the GB power system and the minimum expected values for the system's inertia in the year 2025 are used. The results obtained highlight the benefits on the SFR of utilizing EVs as a dynamic energy storage system for different types of charging and the impact of the measurement delay on the dynamics of the response.