青豫直流受端中点分压器投退策略研究  

Research on entry and exit strategy of midpoint voltage divider in receiving side of Qingyu HVDC

作　　者：刘凯[1] 邹强[1] 张庆武[1] 肖建民[1] 刘孝辉[1] LIU Kai;ZOU Qiang;ZHANG Qingwu;XIAO Jianmin;LIU Xiaohui(NR Electric Co.,Ltd,Nanjing 211102)

机构地区：[1]南京南瑞继保电气有限公司,南京211102

出　　处：《电气技术》2021年第4期20-25,56,共7页Electrical Engineering

基　　金：国家重点研发计划项目(2016YFB0900600)。

摘　　要：青豫直流工程受端分层接入两个500kV交流电网,其交流侧存在分裂与合环两种运行方式,直流系统需要适应分层和不分层两种控制模式。本文介绍了青豫直流工程的系统结构特点,分析了直流中点分压器故障对直流分层接入系统运行的影响及现有应对策略的不足;提出了适应青豫工程结构特点的直流中点分压器投退策略,满足运行需求的同时,避免了直流中点分压器故障后控制系统长期使用电压计算值给直流运行带来的风险,解决了直流中点分压器非电量保护动作导致换流器长时间闭锁的问题,提升直流运行的可用率。The receiving side of Qingyu HVDC is hierarchically connected to two 500kV AC grid,which has spilt and closed loop opera-tion modes.HVDC system needs to be compatible with hierarchical and non-hierarchical control modes.This paper intro-duced AC/DC power grid structure characteristics of Qingyu HVDC,analyzed the influence of DC midpoint voltage divider fault on HVDC and the shortage of existing coping strategies.Then,the entry&exit strategy of midpoint voltage divider which can adapt to the structure characteristics of Qingyu HVDC is proposed.At the same time,the risk of HVDC operation caused by long-term use of calculated value of control system after mid-point voltage divider fault is avoided.It also solves the problem of long-time block of the converter after non-electric protection action of midpoint voltage divider,and improves the available rate of HVDC operation.

关 键 词：分层接入 直流中点分压器故障 测点切换 母联开关 

分 类 号：TM721.1[电气工程—电力系统及自动化]