直流换流站中性母线避雷器组故障仿真研究  

Fault Simulation of Neutral Bus Arrester in DC Converter Station

作　　者：刘志远 于晓军 李秀广 李江涛[2] 郭洁[2] 何家欣 虞江华 LIU Zhiyuan;YU Xiaojun;LI Xiuguang;LI Jiangtao;GUO Jie;HE Jiaxin;YU Jianghua(State Grid Ningxia Electric Power Co.,Ltd.,Yinchuan 750000,China;Xi′an Jiao Tong University,Xi′an 710049,China;Anhui Huidian Technology Co.,Ltd.,Hefei 230088,China)

机构地区：[1]国网宁夏电力有限公司,银川750000 [2]西安交通大学电气工程学院,西安710049 [3]安徽徽电科技股份有限公司,合肥230088

出　　处：《电瓷避雷器》2022年第2期86-92,共7页Insulators and Surge Arresters

基　　金：宁夏回族自治区电力公司科技项目(编号:SGTYHT/17-JS-201)。

摘　　要：直流换流站中性母线避雷器在限制过电压过程中需要吸收大量能量,因此采用大规模多柱并联结构。为了研究中性母线多柱并联避雷器组的故障暂态特性,基于宁东-青岛±660 kV特高压直流输电工程,利用PSCAD程序建立系统仿真模型,计算避雷器组参数并建立多柱并联避雷器组模型,仿真得到不同运行方式下典型故障时中性母线避雷器过电压、电流及吸收能量的波形,分析波形特征。研究避雷器组自身发生击穿故障时的特性以及对系统的影响。仿真结果显示,在发生单极阀顶接地故障时中性母线EM避雷器吸收能量21 MJ,当某一柱伏安特性降低10%时,流过电流及吸收能量远超其他柱,当吸收能量超出其热容量时,电阻片损坏并发生闪络故障,电流集中流过闪络通道,母线电压快速跌落至零。The neutral bus arrester of DC converter station needs to absorb a lot of energy in the process of limiting over-voltage, so large-scale multi-column parallel structure is adopted. In order to study the fault transient characteristics of multi-column arresters at neutral bus, the system simulation model is established by PSCAD program based on Ningdong Qingdao ±660 kV UHVDC transmission project. The parameters of arresters are calculated and the model of multi-column arresters is established. The overvoltage, current and absorbed energy of the neutral bus arresters under different operation modes are si-mulated, and the analysis of waveform characteristics is put forward. The author studies the characteristics of the breakdown fault of the arresters and its influence on the system. The simulation results show that the energy absorbed by the neutral bus EM arrester is 21 MJ when grounding fault at top of converter under mono-polar metallic return. When the volt-ampere curve of one column is reduced by 10%, the current and energy absorbed are much higher than that of other columns. When the energy absorbed exceeds its thermal capacity, the varistor will be damaged and cause flashover. The current flows through the flashover channel intensively, and the voltage on neutral bus drops to zero rapidly.

关 键 词：高压直流输电 换流站 多柱并联避雷器 PSCAD 能量吸收能力 

分 类 号：TM721.1[电气工程—电力系统及自动化] TM862