A Disposal Strategy for Tight Power Balance Considering Electric Vehicle Charging Station Providing Flexible Ramping Capacity

To tackle the high stochastic characteristic of renewable energy resources, such as wind power, sufficient flexibility is of great necessity to the security and economic operation of power systems. With increasing wind power penetration in the power system, the flexibility demand and the possibility of wind spillage are on the rise. Under the tight power balance state, the flexibility solely provided by thermal units will reduce the system flexibility, resulting in load shedding. It is imperative to utilize flexible resources to reduce wind spillage and load shedding. To address the above problems, the power system flexibility supply and demand model and electric vehicle (EV) charging stations operation model are first constructed in this paper. On this basis, a disposal strategy for tight power balance with EV charging stations providing flexible ramping capacity is established. Finally, numerical simulations are conducted on the modified IEEE 118-bus system. Results show that the integration of EV charging stations reduces the operation cost of the system by 11.72%, wind spillage by 17.88%, load shedding by 59.42% and provides flexibility to the system.