Frequency and Voltage Index Control of EV's Intelligent Integrated Station

Frequency deviation and voltage fluctuation are two major concerns in planning and security assessment of power systems. This paper presents a novel electric vehicle (EV) intelligent integrated station (IIS) concept to provide frequency and voltage control ancillary services to the grid. The IIS can be operated in normal, protective, and isolated modes, considering the operating states of the grid. The concept of generalized energy is applied in responding to the actual losses in the charging/discharging process in order to study the power/energy flow. By making the full use of battery storage system in the IIS, the proposed active power-frequency control and the reactive power-voltage control can strengthen the grid stability under normal operation conditions. Simulation results are presented to demonstrate the effectiveness of the proposed frequency/voltage control approaches in a selected distribution network. Results imply that the IIS can mitigate the frequency deviation and voltage fluctuations of the grid.