Voltage Analysis on MV/LV Distribution Networks with the Integration of DC Fast Chargers

The development of ultra-low carbon emission electric vehicles (EVs) has been grown rapidly over the last years in response to the large share of greenhouse gas emissions contributed by the transportation sector. One of the main issues among EV drivers is range anxiety, which mainly results from the long charging battery durations. DC fast charging, the latest charging technology, aims to shorten charging duration; however, the success of e-mobility will be also related to the capacity of the distribution network to integrate the new EVs and their chargers. Specifically, the integration of EVs and DC fast chargers will increase the peak demand and may pose significant challenges for MV and LV distribution networks if adequate control measures are not implemented. This paper introduces a topology for the modelling and connection of a DC fast charger on a real MV/LV distribution network and ensures that the network operates within acceptable limits and that consumers connected to it are minimally affected. Simulation results show that DC fast chargers stress the LV distribution network by causing grid congestions; however, local voltage control measures and a vehicle-to-grid technology can improve some of the grid-side challenges.