Electric vehicle charging energy management for voltage control in low-voltage distribution networks

Electric vehicles (EVs) serve as valuable flexible loads for demand response (DR) programs. These types of programs aim to adapt the consumption or production of a load using external signals to match specific grid requirements. For instance, ancillary system services can use EVs to assist in grid operation by adjusting their charging profile to match with the operational conditions of the power grid. This paper presents an EV charging energy management system (EVC-EMS), designed to extract EV-based flexibility at local charging stations, manage EV charging rates to compute and inform an external flexibility service provider (FSP) of available demand flexibility, and dispatch flexibility upon request. As a proof-of-concept for the functionality of the EVC-EMS, a test scenario focusing on exploiting EV charging station flexibility to manage voltage in a low-voltage (LV) distribution network has been developed. The results show that coordinating the EV supply equipment with the help of the EVC- EMS can be successfully utilized for a fast DR program. The tested DR scheme can perform voltage control in the LV network by considerably reducing overvoltages.