Research on frequency regulation using scheduling capacity of electric vehicles

Nowadays, growing number of electric vehicles (EVs) can not only be controllable load to regulate power system, but also serve as distributed energy storage unit that can feedback to the grid by vehicle-to-grid (V2G). Therefore, ancillary services for the grid such as frequency regulation can potentially be provided by the use of EVs with scheduling capacity. However, the scheduling capacity is limited by factors such as the constraints of customers travel demand and the battery life. Based on this, a centralized control mode is applied for distributed EVs and a mathematical model with charging and discharging static frequency characteristics of aggregators is established, considering EVs scheduling capacity. According to this, load frequency control models both for single and two-area power systems are proposed. The simulation results show that using EVs scheduling capacity for frequency regulation can effectively help reducing the system frequency deviation and thus improving the electricity quality. Furthermore, the reserve capacity of traditional frequency regulation units can be decreased and especially power system economics has developed.