Multi-Stage Robust Reactive Power Optimization in Active Distribution Networks With Discrete Intertemporal Constraints

• Published in: IEEE transactions on power systems Vol. 40; no. 5; pp. 4131 - 4144
• Main Authors: Guo, Zhongjie, Wei, Wei, Cao, Xiaoyu, Hu, Weihao
• Format: Journal Article
• Language: English
• Published: IEEE 01.09.2025
• Subjects: Couplings; Decision making; distribution network; Distribution networks; Load flow; Mathematical models; multi-stage robust optimization; non-anticipativity; Optimization; Reactive power; Reactive power regulation; Regulation; Renewable energy sources; Uncertainty
• ISSN: 0885-8950; 1558-0679
• DOI: 10.1109/TPWRS.2025.3543358

Reactive power regulation is crucial for active distribution networks (ADNs). This paper studies the multi-stage reactive power optimization in ADNs with renewables considering intertemporal constraints imposed on total action times of discrete regulation facilities. First, we regard reactive power regulation as a sequential decision-making process and formulate it as a multi-stage robust optimization problem with hybrid continuous and discrete recourses. Then, we propose a customized implicit policy method to solve this problem, devising bounding variables and non-anticipative constraints of shunt capacitor bank (SCB) and on-load tap changer (OLTC). Next, the bounding variables are optimized prior to dispatch subject to non-anticipative constraints; with their help, intertemporal couplings are broken and the multi-stage robust optimization problem shrinks to a two-stage robust one, which can be solved by decomposition algorithms. Finally, we use the bounding variables to build a non-anticipative and robustly feasible policy based on time-decoupled optimal power flow (OPF) where intertemporal constraints are relaxed but satisfied at the optimums. Case studies on the modified IEEE 33-bus, 69-bus, and 123-bus systems verify the advantages of the proposed method.