Multiple Sources Restoration for Soft Open Points in Distribution Networks With a Two-Stage Accelerated Algorithm
Tao Zhang, Xiaodan Yu, Yunfei Mu, Hongjie Jia, Kai Hou, Xiaolong Jin
Abstract
Soft open points (SOPs) connected to distribution networks are instrumental in improving operational performance during outage periods, such as power supply reliability and power quality, and they have not been sufficiently studied. To fully harness the potential benefits of SOPs, a multiple-source distribution service restoration (DSR) strategy considering SOPs is proposed in this paper. The power outputs of distributed energy resources (DERs) and SOP flexibility are exploited to enhance the load restoration level and mitigate voltage deviations over a time horizon. Additionally, to cope with uncertainties, the chance-constrained method is adopted by the proposed strategy to allow intermittent renewable resources to participate in DSR. DSR is formulated as a mixed-integer linear programming (MILP) problem with many integer variables, making it very challenging to solve. To reduce the computational complexity, a two-stage accelerated algorithm (TSAA) is proposed. This allows us to solve a relaxed MILP problem in the first stage to decide the radial topology. An accelerated MILP problem is solved in the second stage to determine the load status as well as the outputs of the DERs and SOPs. Case studies on an IEEE 33-bus distribution network illustrate the effectiveness of the proposed DSR strategy and the feasibility of TSAA in reducing the computation time.