强风雨天气等极端灾害下的配电网弹性提升优化策略

Optimization Strategy of Distribution Network Resilience Enhancement under Extreme Disasters as Heavy Wind and Rain Weather

为提高电力系统应对强风雨天气等极端灾害的预防、抵抗和快速响应能力,提出计及强风雨天气等极端灾害下线路故障概率的配电网两阶段弹性提升优化策略。为确定强风雨天气的易发区域,基于K-means算法对强风雨天气发生区域进行聚类分析,得到配电网所在区域内K类极端天气的发生概率。进而研究基于强风雨天气破坏强度的元件故障概率模型,并通过蒙特卡洛模拟,将强风雨影响下的线路故障概率转换为场景概率,同时将场景数量简化。在各场景下,考虑包括线路加固、分布式电源部署等灾前强化和网络重构、线路修复等灾后响应措施,以弹性提升策略成本期望最小为目标,以灾前强化成本约束、灾中考虑网络重构的运行约束以及灾后线路修复逻辑为约束条件,建立随机优化模型。通过算例分析验证该模型在各类极端天气场景影响下对电力系统恢复的有效性。分析结果表明,将灾前强化策略和灾后恢复策略结合得到的两阶段弹性提升优化策略,在各类强风雨天气等极端灾害影响下能够更快更好的恢复系统负荷,有效提升电力系统应对极端灾害的快速响应能力。

To improve the prevention,resistance,and rapid response capability of the power system to cope with extreme disasters,a two-phase resilience enhancement optimization strategy for distribution grids is proposed to take into account the probability of line failures under extreme disasters such as heavy wind and rain.First of all,to determine the prone area of heavy rain and wind,based on the K-means algorithm,the clustering analysis of heavy rain and wind occurrence area is carried out to get the probability of occurrence of K types of extreme weather in the area where the distribution network is located.Second,the component failure probability model based on the damage intensity of heavy wind and rain weather is studied,followed by Monte Carlo simulation,which converts the line failure probability under the influence of heavy wind and rain into the scenario probability.At the same time,the number of scenarios is simplified.Under each scenario,the stochastic optimization model is established by considering pre-disaster reinforcement including line reinforcement and distributed power supply deployment,and post-disaster response measures including network reconfiguration and line repair,to minimize the cost expectation of the resilience enhancement strategy,and with the cost constraints of pre-disaster reinforcement,the operational constraints of network reconfiguration considered in the middle of the disaster,and the logic of line repair in the post-disaster period as the constraints.The effectiveness of the model for power system restoration under the influence of various types of extreme weather scenarios is verified through case analysis.The results show that the two-stage resilience improvement optimization strategy combined with the pre-disaster strengthening strategy and the post-disaster recovery strategy can recover the system load faster and better under the influence of various extreme disasters such as strong wind and rain weather,and effectively improve the rapid response ability of the power system to deal with extreme disasters.