Control of Electric Vehicles Charging Without Communication Infrastructure

This paper presents a study of controlled charging of electric vehicles (EVs) using a fuzzy logic controller. The controller regulates the charging power according to the state of charge (SoC) of EV and the voltage at the point of connection of EV charger. The objective of the controller is to charge EVs while keeping the voltage of different distribution system points within the acceptable limits. Most of the proposed methods for controlled charging of EVs depend on the availability of the communication infrastructure which enables communication between utility operator and EV chargers which is not available in the current distribution networks and requires a huge investment. So, an autonomous controller which does not need communication infrastructure is developed in this study. The controller is designed to charge EVs without violating the voltage limits which can occur in case of uncontrolled charging of EVs. The effectiveness of the controller is tested on a residential low voltage (LV) distribution network and the simulations are executed with MATLAB/SIMULINK. The network performance in case of controlled charging of EVs is compared with the uncontrolled charging of EVs and the base case when no EVs are connected. The results demonstrate the distinction of the proposed controlled charging method in terms of total power demand, transformer loading, cable loading, and voltage profile over uncontrolled charging.