交直流互联系统对电流差动保护的影响分析及对策  

Analysis on the effect of AC /DC interconnected system on the current differential protection and the countermeasure

作　　者：申洪明[1] 黄少锋[1] 费彬[1] 

机构地区：[1]华北电力大学新能源电力系统国家重点实验室,北京102206

出　　处：《华北电力大学学报（自然科学版）》2014年第4期1-6,29,共7页Journal of North China Electric Power University：Natural Science Edition

基　　金：国家重点基础研究发展计划(973计划)资助项目(2012CB215206)

摘　　要：理论分析了交直流互联系统中仅发生交流侧故障时直流系统等值工频变化量电流的特性,然后分别探讨了,直流馈入对与直流系统直接相邻的,输电线路电流差动保护故障分量判据和稳态量判据的影响。研究表明仅发生交流系统故障时,对稳态量电流差动保护影响相对较大,容易引起保护的拒动,然后提出了一种仅基于幅值判据的应对措施。最后基于PSCAD/EMTDC的仿真验证了上述结论的正确性。The characteristic of equivalent DC-system power-frequency current in AC-DC interconnected network under the condition of AC faults without causing commutation failure is studied on a theory level. The performance of two dif- ferential current relays which utilize steady component and fault component respectively for transmission lines those are connected to DC system directly are analyzed. It is showed that the differential current relays using steady component is influenced severely, which is likely to result in mis-operation, then a novel criterion that used to detect internal fault is put forward to solve the problem. At last, simulations results using PSCAD/EMTDC testify the conclusion correctness.

关 键 词：交直流互联系统 等值工频变化量电流 差动保护 幅值判据 

分 类 号：TM77[电气工程—电力系统及自动化]