基于时段主导特征的三相不平衡台区识别及治理  

Identification and Management of Three-phase Imbalanced Station Areas Based on Time-period Dominant Characteristics

作　　者：竺炜[1] 舒慧莹 李娟[2] 竺浩然 ZHU Wei;SHU Huiying;LI Juan;ZHU Haoran(College of Electrical&Information Engineering,Changsha University of Science&Technology,Changsha 410114,Hunan Province,China;Yiyang Power Supply Company,State Grid Hunan Electric Power Company,Yiyang 413000,Hunan Province,China)

机构地区：[1]长沙理工大学电气与信息工程学院,湖南省长沙市410114 [2]国网湖南省电力公司益阳供电公司,湖南省益阳市413000

出　　处：《电网技术》2024年第12期5071-5078,I0060,共9页Power System Technology

基　　金：国家自然科学基金项目(52077009);2024年度湖南省教育厅科研项目。

摘　　要：间歇性家庭新能源及汽车充电桩的单相接入,加剧了台区三相不平衡问题。台区数量巨大且负荷随机性大,导致不平衡台区识别复杂,不平衡治理的人力及物力成本巨大。为减小成本和提高治理效果,该文提出了任选时段(如前日)的主导不平衡度评估及主导相分量平衡的优化方法,以筛选出严重不平衡台区,得到相间负荷转供的方案。研究发现,台区总表三相电流的时序矩阵经奇异值分解后,主导阵为原矩阵的主要成份;由其左奇异向量可表征任选时段内唯一的主导不平衡度、相间转供的方向及主导分量占比;根据右奇异向量的时序特征,可提取重载相的各单相负荷主导及次要分量。故以主导相分量平衡及次要相分量相抵为目标的优化,可避免随机组合寻优的灾难计算量,得到相间转供的单相负荷组合的有效方案。算例验证了所提方法的有效性。该文思路不追求每一时刻的精准,旨在寻求任选时段的总体最优;提出的严重不平衡台区识别及治理方法,具有较好的可行性,对提高配网的供电质量和设备安全性具有实际意义。Single-phase access to intermittent household new energy and vehicle charging piles exacerbates the problem of three-phase imbalance in station areas.The significant number of stations and load randomness lead to the complex identification of imbalanced stations and colossal human and material costs for imbalance management.To reduce the cost and improve the management effect,this paper proposes the dominant imbalance degree assessment of any selected period(e.g.,the day before yesterday)and the optimization method of dominant-phase component balancing to screen out the severely imbalanced station areas and get the inter-phase load transfer scheme.It is found that the time series matrix of the three-phase currents of the total table of the station is decomposed by singular values and the dominant array is the main component of the original matrix;The unique dominant imbalance degree,the direction of interphase transfers and the dominant component share in any chosen period can be characterized by its left singularity vector;according to the time series characteristics of the suitable singular vector,the dominant and the secondary components of each single-phase load of the heavy-loaded phase can be extracted.Therefore,the optimization to balance the dominant phase components and offset the secondary phase components can avoid the catastrophic computation volume of random combination optimization and obtain a practical scheme for the single-phase load combination of inter-phase transfer.The arithmetic example verifies the effectiveness of the proposed method.The idea of this paper does not pursue the accuracy of each moment but aims to seek the overall optimality of any selected period;the proposed method of identifying and managing the severely unbalanced station area has good feasibility and is of practical significance for improving the power supply quality and equipment safety of the distribution network.

关 键 词：台区三相不平衡度 奇异值分解 主导特性 严重不平衡台区识别 相间负荷转供 

分 类 号：TM721[电气工程—电力系统及自动化]