Flexible interconnection strategy for distribution networks considering multiple soft open points siting and sizing

Soft open point (SOP) can control the power flow of distribution network (DN) in real-time and with precision, thereby optimizing system power flow and voltage distribution. Addressing the need for the flexible interconnection of multiple distribution stations under the background of “whole county promotion” of distributed photovoltaics (DPVs), a multi-SOP siting and sizing strategy based on a bi-level programming model and the improved grey wolf optimization (IGWO) algorithm is proposed. The upper-level optimization comprehensively considers configuration costs, operation and maintenance costs, and loss costs, uses IGWO to generate programming schemes, and carries out the siting and sizing of multiple SOPs. Based on the upper-level programming scheme, the lower-level executes the optimal DNs scheduling using second order cone programming (SOCP) algorithm, and then feeds the scheduling costs back to the upper-level. The case study results of this paper indicate that the proposed strategy for siting and sizing of multiple SOPs in multiple DNs effectively combines the internal coordination in a single DN and the flexible complementarity across multiple DNs, thereby reducing system loss and improving economy. © 2024