A Cooperative Scheduling Strategy of Renewable Energy and Electric Vehicle Considering Reactive Power Response

In recent years, with the reform of energy structure, renewable energy systems (RESs) and electric vehicles (EVs) have been rapidly developed worldwide. However, the fluctuation output of RESs and the randomness charging behavior of EVs bring tremendous pressure to the safe and stable operation of the distribution network. With the expansion of the scale of EVs, the impact of disorderly charging on the peak-valley load difference of the system is becoming more significant. In order to avoid this situation, a cooperative scheduling scheme of EVs and RESs based on the vehicle-to-grid (V2G) concept is proposed. By implementing the time-of-use price tariff according to the equivalent load in the EV charging station, the EV owners are encouraged to carry out staggered charge/discharge, and the dispatching center uniformly formulates the charge/discharging plan. Then, the cooperative scheduling scheme of EVs and RESs is introduced in detail, and a two-level model is established for optimization. The goal of the upper model is the charge/discharge power of EVs at each period, which is solved by quadratic programming. The lower model considers the reactive power response of EV and RES plants, which is solved by second-order cone programming. Finally, the simulation is carried out with the improved IEEE-33 node system. The results show that the proposed scheduling strategy can effectively reduce the active power loss and improve the system voltage quality.