摘要
随着新能源发电技术与直流输电技术在大电网中的广泛应用,需要提出含新能源的交直流混联电网静态电压稳定分析方法。为此,该文针对含常规直流输电和多端柔性直流输电的交直流混联电网,采用区间数描述新能源电站出力的不确定波动,建立了交直流混联电网静态电压稳定裕度(static voltage stability margin,SVSM)区间计算的2个双层最优潮流模型,即计算SVSM区间上界的min-min模型和计算SVSM区间下界的max-min模型。计算区间SVSM上界的min-min双层优化模型可直接合并为单层优化模型求解。计算SVSM区间下界的max-min模型需要先通过二阶锥松弛和凸包络松弛等方法将内层模型转化为凸规划模型,并通过对偶优化理论得到内层凸规划模型的对偶规划模型,进而转化为单层优化模型求解。通过对修改后的IEEE-39节点系统和南方电网2个交直流混联电网算例的计算分析,并与蒙特卡洛抽样法和拉丁超立方抽样法的计算结果比较,验证了所提出方法的正确性与高效性。
With the wide application of renewable energy generation technology and HVDC technology in a large-scale power grid, it is necessary to propose a method to analyze the static voltage stability of AC/DC hybrid power grid with renewable energy. Thus, for an AC/DC hybrid power grid with conventional DC transmission and multi-terminal flexible DC transmission, the interval number is used to describe the uncertain fluctuation of renewable energy generation output.Two bi-level optimal power flow models for calculating the static voltage stability margin interval(SVSM) of AC/DC hybrid power grid are established, which are a min-min model for calculating the upper bound of SVSM interval and a max-min model for calculating the lower bound. The min-min bi-level optimization model for calculating the upper bound of SVSM interval can be solved by merging into a single-layer optimization model directly. The max-min model for calculating the lower bound of SVSM interval requires transforming the inner optimization model into a convex optimization model by using the second-order cone relaxation and the convex hull relaxation methods, and obtains the dual optimization model of the inner convex optimization model with the dual optimization theory. Then it can be solved by merging into a single-layer optimization model. Case studies are carried out in two AC/DC hybrid power grids, the modified IEEE-39 bus system and the actual China Southern Power Grid, and the obtained results are compared with the Monte Carlo sampling method and the Latin hypercube sampling method, which demonstrate the correctness and efficiency of the proposed method.
作者
陈刚
刘万彬
杨悦荣
郑外生
涂思嘉
林舜江
赵利刚
周保荣
姚文峰
CHEN Gang;LIU Wanbin;YANG Yuerong;ZHENG Waisheng;TU Sijia;LIN Shunjiang;ZHAO Ligang;ZHOU Baorong;YAO Wenfeng(State Key Laboratory of HVDC(CSG Electric Power Research Institute),Guangzhou 510663,Guangdong Province,China;School of Electric Power Engineering,South China University of Technology,Guangzhou 510640,Guangdong Province,China;China Southern Power Grid,Guangzhou 510663,Guangdong Province,China)
出处
《电网技术》
EI
CSCD
北大核心
2023年第3期1127-1137,共11页
Power System Technology
基金
国家自然科学基金项目(51977080)
直流输电技术国家重点实验室2020年开放基金项目(SKLHVDC-2020-KF-13)。
关键词
静态电压稳定裕度
交直流混联电网
最优潮流法
区间优化
对偶优化理论
凸松弛
static voltage stability margin
AC/DC hybrid power grid
optimal power flow
interval optimization
dual optimization theory
convex relaxation
