Electric vehicles have become a crucial component of modern power systems, possessing substantial energy reserves that can be important power supplies in blackouts where the power grid has weak reserves or limited connections to other grids. In order to clarify the technical conditions and control methods of the centralized electric vehicle charging station as the black-start power source of the power grid, assuming that the centralized electric vehicle charging station can be considered a single, large-scale energy storage system, this paper proposes a three-stage coordinated recovery strategy based on the centralized electric vehicle charging station. The strategy involves three distinct stages, beginning with the establishment of AC frequency and voltage by the electric vehicle charging station to initiate the auxiliary load of the power plant. In the middle stage, considering the traditional generator has been connected, the charging station’s control mode is set to provide constant active and reactive power output, providing extra voltage and frequency support to the grid-connected generating units and crucial loads. Finally, in the later stage, control strategies are tailored to the charging power stations’ capacities, with one group of additional oscillation damping controllers, while the other group adopts additional frequency control to decrease power disturbances, ensuring a smooth recovery of the power grid. A PSCAD/EMTDC-based model was constructed to verify the proposed coordinated grid recovery strategies. The results demonstrated that the centralized station successfully established the voltage and frequency of the AC system, and the designed additional controller also made the recovery process much more stable.

The interline power flow controller (IPFC) presents a promising solution for managing the directional and quantitative interaction of power between different lines, facilitating a significant improvement in power system stability. Based on such a background, this paper proposes a dynamic droop control strategy to improve frequency stability through the use of IPFC equipment. To enhance the active power support ability of the IPFC, additional frequency control for the IPFC’s active power control loop is designed with droop control, where each IPFC’s power flow control limitations are also considered to make sure the original power of each line is controllable. Besides the addition of such basic control, the proposed droop strategy is designed in a dynamic style. The droop coefficients of each IPFC can be varied according to each line’s power transmission margin, such that the power fluctuations can be shared more reasonably based on such a dynamic droop coordination strategy. The proposed methods are verified through PSCAD simulations. The results show that the dynamic droop control cannot only suppress the frequency disturbance, but also make power dispatch more efficient.