青藏直流联网工程直流谐波保护研究  

Research on DC Harmonic Protection in Qinghai-Tibet HVDC Project

作　　者：吉程[1] 文俊[1] 刘宝宏[2] 刘婷婷[1] 符茜茜 韩民晓[1] 

机构地区：[1]华北电力大学电气与电子工程学院,北京102206 [2]国家电网公司直流建设分公司,北京100052

出　　处：《现代电力》2016年第1期74-79,共6页Modern Electric Power

基　　金：国家自然科学基金项目(51177044)

摘　　要：介绍了青藏直流联网工程试运行期间发生的两次直流闭锁故障,分析了事故原因,并说明了相应的直流谐波保护修改措施。在此基础上介绍了换流器直流侧低次非特征谐波产生的机理以及直流谐波保护的逻辑原理。通过PSCAD/EMTDC软件对各类可能在直流线路中产生低次谐波的故障进行仿真,明确了各类故障在直流线路上产生谐波的次数以及含有率。最后提出:在原有谐波保护改进的基础上,令青藏直流新增的150Hz谐波保护,作为阀短路保护的后备保护。仿真证明此措施提高了工程的稳定性,也拓展了150Hz保护这一新型保护的适用范围。In this paper,two blockings failures of QinghaiTibet HVDC project during its pilot operation are introduced,their causes are analyzed,and improved measures of relative DC harmonic protection are discussed.Then the causing mechanism of low-order harmonic in DC side and the logic mechanism of DC harmonic protection are introduced.The simulations for all kinds of low-order harmonic faults in DC transmission lines are carried out by using PSCAD/EMTDC software,and the harmonics frequency and magnitude of all faults have been determined.In the end,based on the improvement of Qinghai-Tibet HVDC project,a kind of new 150 Hz harmonic protection is applied as the backup protection of valve short circuit protection.Simulations show that proposed measure can improve the stability of the project,which widens the application area of this new 150 Hz protection.

关 键 词：直流谐波保护 150Hz保护 高压直流输电 主变充电 直流闭锁 

分 类 号：TM773[电气工程—电力系统及自动化]