新型电力系统全息电流采样值差动保护仿真研究  

Simulation Research on Differential Protection of Holographic Current Sampling Value in Novel Power System

作　　者：宋小舟[1] 伍叶凯[2] 陈昊 杨卉卉[1] 屠黎明[2] 肖正强[1] 刘怀宇 SONG Xiaozhou;WU Yekai;CHEN Hao;YANG Huihui;TU Liming;XIAO Zhengqiang;LIU Huaiyu(Beijing Sifang Jibao Engineering Technology Co.,Ltd.,Beijing 100085,China;Beijing Sifang Automatization Co.,Ltd.,Beijing 100085,China;Nanjing Power Supply Branch,State Grid Jiangsu Electric Power Co.,Ltd.,Nanjing Jiangsu 210019,China;EHV Branch,State Grid Jiangsu Electric Power Co.,Ltd.,Nanjing Jiangsu 211102,China)

机构地区：[1]北京四方继保工程技术有限公司,北京100085 [2]北京四方继保自动化股份有限公司,北京100085 [3]国网江苏省电力有限公司南京供电分公司,江苏南京210019 [4]国网江苏省电力有限公司超高压分公司,江苏南京211102

出　　处：《湖北电力》2023年第1期1-8,共8页Hubei Electric Power

基　　金：国家自然科学基金项目(项目编号:51807028)。

摘　　要：传统电力系统故障电流的谐波含量较低,继电保护主要考虑50 Hz的故障电流,一般忽略谐波故障电流对动作特性的影响。新型电力系统中,大量电力电子器件的应用,谐波故障电流含量大幅增加,与频率无关的包含谐波电流的保护原理更能反映故障的特性。柔性低频输电系统在发生故障时,换流器的短路电流承受能力有限,保护对速动性的要求较高,谐波较传统系统复杂,传统基于工频量的交流保护原理不再适用。采样值差动原理保护基于基尔霍夫定律,在50 Hz电力系统的变压器、母线和线路保护得到广泛应用,具有动作速度快、抗干扰能力强、无惧谐波等特点,因此,开展采样值差动保护的适应性研究,具有较强的现实意义。根据新型电力系统和柔性低频输电系统故障电流的特点,分析了全息电流采样值差动应用在变压器、母线和线路保护的可行性,提出了基于制动系数可变动作区间的采样值差动方案,为新型电力系统差动保护选用提供了一种可行性方案。The harmonic content of fault current in the traditional power system is low.50 Hz fault current is mainly considered in relay protection,and the influence of harmonic fault current on operation characteristics is generally ignored.In the new power system,with the application of a large number of power electronic devices,the content of harmonic fault current increases greatly,and the protection principle that contains harmonic current independent of frequency can better reflect the fault characteristics.The short-circuit current bearing capacity of the converter is limited when the fault occurs in the flexible low-frequency transmission system.The protection requires high speed;the harmonics are more complex than the traditional system,and the traditional AC protection principle based on power frequency is no longer applicable.Therefore,it is of great practical significance to study the adaptability of sampling differential protection.This paper is based on the characteristics of fault current in new power system and flexible low-frequency transmission system to analyze the feasibility of applying holographic current sampling value differential in transformer,bus and line protection.The paper also proposes a sampling value differential scheme based on variable action interval of braking coefficient,which provides a feasible scheme for differential protection selection of novel power system.

关 键 词：低频输电 采样值 全息电流 差动保护 

分 类 号：TM73[电气工程—电力系统及自动化]