考虑解列后孤网暂态稳定性的解列时刻实时决策方法  

Real-time Decision-making Method of Splitting Time Considering Transient Stability of Isolated Power Grid After Splitting

作　　者：刘福锁[1,2] 方勇杰 吴雪莲[3] LIU Fusuo;FANG Yongjie;WU Xuelian(School of Electrical and Electronic Engineering,North China Electric Power University,Beijing 102206,China;State Key Laboratory of Smart Grid Protection and Control,Nanjing 211006,China;NRAI Technology Co.,Ltd.,Nanjing 211006,China)

机构地区：[1]华北电力大学电气与电子工程学院,北京市102206 [2]智能电网保护和运行控制国家重点实验室,江苏省南京市211006 [3]国电南瑞科技股份有限公司,江苏省南京市211006

出　　处：《电力系统自动化》2022年第22期83-89,共7页Automation of Electric Power Systems

基　　金：国家自然科学基金资助项目(61933005)。

摘　　要：失步解列时刻是影响解列后孤网能否保持同步稳定运行的关键参量,考虑孤网暂态稳定约束的解列时刻实时决策是需要持续开展研究的难题。文中分析了在解列时刻实时精准判断解列后孤网暂态稳定性面临的问题,梳理了解列时刻实时决策中需考虑的关键因素,将决策问题分解为失步振荡的允许持续时间判断、解列后暂态稳定裕度最小的孤网识别和解列后孤网暂态稳定裕度局部极大值出现时刻判别等3个子问题。在假设可以无延时地获得系统运动轨迹的前提下,提出了一种解列时刻实时决策的方法。所提方法利用原系统失稳或失步作为启动判据,以电网对失步振荡持续时间的可接受性和解列后孤网暂态稳定裕度满足设定阈值为约束条件,根据估算的解列后孤网暂态稳定裕度随解列时刻的变化趋势指标,识别孤网暂态稳定裕度极大值的出现时刻,触发解列控制的执行。算例分析验证了所提决策方法的可行性和有效性。Out-of-step splitting time is a key parameter that affects whether the isolated network can maintain synchronous and stable operation after splitting. Real-time decision-making of splitting time considering transient stability constraints of isolated power grid is a difficult problem that needs continuous research. This paper analyzes the problems faced by real-time accurate judgment of the transient stability of isolated power grid after splitting at the time of splitting, sorts out the key factors to be considered in real-time decision-making at the time of splitting, and divides the decision-making problem into three sub-problems,i.e., judgment of the allowable duration of out-of-step oscillation, identification of isolated power grid with the smallest transient stability margin after splitting, and judgment of the time when the local maximum of the transient stability margin of isolated power grid after splitting. Under the assumption that the system motion trajectory can be obtained without delay, a real-time decisionmaking method for splitting time is proposed. The proposed method uses the instability or out-of-step of the original system as the starting criterion, and takes the acceptability of the power grid for the duration of out-of-step oscillation and the transient stability margin of the isolated power grid after splitting satisfies the set threshold as constraints. According to the estimated variation trend index of the transient stability margin of the isolated power grid after splitting with the time of splitting, the occurrence time of the maximum value of the transient stability margin of the isolated power grid is identified, and the implementation of the splitting control is triggered. The feasibility and effectiveness of the proposed decision-making method are verified by an example.

关 键 词：电网解列 暂态稳定 暂态能量 稳定裕度 扩展等面积准则 

分 类 号：TM712[电气工程—电力系统及自动化]