基于自主芯片的接地变压器接地故障检测方法研究  

Research on detection method of grounding fault for grounding transformer based on domestic independent chips

作　　者：董凯达[1] 钱建国 马伟 DONG Kaida;QIAN Jianguo;MA Wei(NR Electric Co.,Ltd.,Nanjing 211102,China;State Grid Zhejiang Electric Power Co.,Ltd.,Hangzhou 310007,China;State Grid Hangzhou Power Supply Company,Hangzhou 310009,China)

机构地区：[1]南京南瑞继保电气有限公司,江苏南京211102 [2]国网浙江省电力有限公司,浙江杭州310007 [3]国网浙江省电力有限公司杭州供电公司,浙江杭州310009

出　　处：《供用电》2022年第11期40-46,共7页Distribution & Utilization

基　　金：国家电网有限公司科技项目(5500-202046258A-0-0-00)。

摘　　要：随着配电网及新能源供电系统对地电容电流水平的提高,中性点经小电阻接地方式得到了越来越广泛的应用。中性点经小电阻接地系统中若发生接地变压器故障,其保护跳闸时会直接跳开主变压器或者母线开关,这增加了整段母线失压的风险。提出了基于零序功率检测接地变压器自身接地故障的保护方法,在接地变压器自身接地故障时只跳开接地变压器的开关,后续再人工切换运行方式,可以降低整段母线失电的风险,提高供电可靠性。此外,还提出了使用国内自主芯片实现该保护,既能够防范国外芯片断供的风险,又能够通过多核处理器的“保护核+启动核”的冗余校验模式提高保护的可靠性。With the rising capacitive current level of the distribution and new-energy power network,the neutral point through lowresistance grounded power system is used more and more widely.When a grounding fault occurs at the grounding transformer in the neutral point through low-resistance grounded power system,the breakers of the main transformer and the bus bar will be tripped by the relay of the grounding transformer,which may increase the risk of power loss of the whole bus bar.In the paper,a relay method based on the zero-sequence power is raised to distinguish the in-area grounding faults of the grounding transformer from the out-area ones,and as a result,only the breaker of the grounding transformer itself will be tripped when an in-area grounding fault occurs,and then the operation mode of the distribution power grid can be switched manually later,so the risk of power loss of the whole bus bar can be reduced and the reliability of power supply can be increased.On the other hand,the use of chips with domestic independent intellectual property rights in the protection relay area is raised in the paper,which can not only prevent the risk of foreign chip supply stop,but also improve the protection reliability through the redundancy checking mode of"protection core+startup core"by using the multi-core processor.

关 键 词：小电阻接地系统 接地变压器 接地故障 零序保护 零序功率 高阻接地故障 

分 类 号：TM77[电气工程—电力系统及自动化]