Coordinated optimization for controlling short circuit current and multi-infeed DC interaction

Due to increased penetration of renewable energies, DC links and other emerging technologies, power system operation and planning have to cope with various uncertainties and risks. In order to solve the problems of exceeding short circuit current and multi-infeed DC interaction, a coordinated optimization method is presented in this paper. Firstly, a branch selection strategy is proposed by analyzing the sensitivity relationship between current limiting measures and the impedance matrix. Secondly, the impact of network structure changes on the multi-infeed DC system is derived. Then the coordinated optimization model is established, which considers the cost and effect of current limiting measures, the tightness of network structure and the voltage support capability of AC system to multiple DCs. Finally, the non-dominated sorting genetic algorithm II combining with the branch selection strategy, is used to find the Pareto optimal schemes. Case studies on a planning power system demonstrated the feasibility and speediness of this method.