A Hierarchical Control Scheme for Electric Vehicle Charging Stations Coordinated Operation

Abstract

This paper deals with standalone coordinated operation of multiple electric vehicle charging stations (EVCS). A hierarchical control scheme is proposed to achieve power management among multiple EVCS. Each EVCS includes renewable energy source (RES), energy storage system (ESS), and controllable charging slots. The proposed control method maintains constant load demand on sources by compensating EVCS dynamic locally. Therefore, the sources are free from transient in EVCS. This improves the stability of system. The proposed control also improves the voltage regulation at each bus in the system under various operating conditions. The combined operation of sources and local controller in each EVCS achieves effective power management in the system. In absence of sources, the EVCS operates as voltage source and its smooth transition of EVCS is possible with proposed control scheme. The proposed control technique is tested under different operating condition in real time simulator.