支路短路电流直流分量及衰减时间常数计算方法  

Study on calculation methods for DC component and decay time constant of branch short circuit current

作　　者：曹炜 张正 陈春阳 张捷 CAO Wei;ZHANG Zheng;CHEN Chunyang;ZHANG Jie(Electric Power Engeering of Shanghai University of Electric Power, Shanghai 200090, China;Xinyang Power Supply Company,State Grid Henan Electric Power Co., Ltd., Xinyang 464000, China)

机构地区：[1]上海电力大学电气工程学院,上海200090 [2]国网河南省电力公司信阳供电公司,河南信阳464000

出　　处：《电力科学与技术学报》2021年第2期31-39,共9页Journal of Electric Power Science And Technology

基　　金：国家自然科学基金青年科学基金(51807114)。

摘　　要：随着电力系统电压等级的提高,直流分量对断路器开断能力的影响被密切关注,但针对断路器支路短路电流直流分量计算方法的研究却非常少。基于此,提出一种基于转移阻抗实现支路短路电流直流分量及其衰减时间常数计算的方法。利用支路追加法形成节点阻抗矩阵的原理,在已知原网络节点阻抗矩阵的条件下,根据系统短路时网络的特点,使变换后的网络能够方便地进行各断路器支路短路电流直流分量及其衰减时间常数的计算,并归纳出计及网络拓扑结构变化时修正节点阻抗矩阵的统一算法,该算法具有计算速度快、物理概念清晰以及易于编程实现扫描计算等特点。EMTP仿真验证该文方法的准确性,并与PSS/E计算支路短路电流直流分量的计算结果进行比较,验证本文方法的优越性。As the voltage level of the power system increases,the DC component influence on the breaking capacity of the circuit breaker has been closely concerned.However,there are few studies on the calculation method of DC component of short circuit current in the circuit breaker branch.In this paper,a calculation method is proposed for the DC component of branch short-circuit current and its decay time constant based on transfer impedance.Firstly,in the case of knowing the impedance matrix of the original network and considering the characteristics of the network when the system is short-circuited,the network is transformed based on the principle of forming the node impedance matrix using the branch-adding method.Then,the transformed network can easily calculate the DC component of the short-circuit current and the decay time constant of each branch.In addition,a unified algorithm for forming the node impedance matrix is concluded when considering the changes of the network topology.It has the advantages of fast calculation speed,clear physical concept,and it is easy to program so as to achieve scanning calculations.The accuracy of the proposed method is verified by EMTP simulation.Compared with results from PSS/E,the superiority of the proposed method is also verified.

关 键 词：支路追加法 短路电流 直流分量 衰减时间常数 转移阻抗 

分 类 号：TM713[电气工程—电力系统及自动化]