一起系统间歇性接地导致电磁式电压互感器的分析及改进措施  

Analysis and Improvement Measures of Inductive Voltage Transformer Fault Caused by Intermittent Grounding

作　　者：牛勃 吴旭涛 张国勇 马飞越 谭东现 何帅 NIU Bo;WU Xutao;ZHANG Guoyong;MA Feiyue;TAN Dongxian;HE Shuai(Power Research Institute of State Grid Ningxia Power Co.,Ltd.,Yinchuan 750001,China;Anhui Zhengguang Electric Power Technology Co.,Ltd.,Hefei 230088,China;Shanghai ROX Electric Co.,Ltd.,Shanghai 201807,China;Wuzhong Company of State Grid Ningxia Power Co.,Ltd.,Ningxia Wuzhong 751100,China)

机构地区：[1]国网宁夏电力有限公司电力科学研究院,银川750001 [2]安徽正广电电力技术有限公司,合肥230088 [3]上海雷博司电气股份有限公司,上海201807 [4]国网宁夏电力有限公司吴忠供电公司,宁夏吴忠751100

出　　处：《高压电器》2020年第10期70-74,83,共6页High Voltage Apparatus

摘　　要：电磁式电压互感器一次侧用压敏消谐装置串接于一次侧中性点与地之间,通过谐振过程中装置两端施加电压进行铁磁谐振抑制,该种谐振抑制措施在谐振过程易发生保险熔断、互感器炸裂,影响系统稳定运行。文中通过对一起因系统间歇性接地导致电磁式电压互感器炸裂故障原因分析,提出一种基于PTC热敏电阻的电磁式电压互感器一次侧用流敏消谐装置,其通过谐振过程中装置两端通流状态进行铁磁谐振抑制。试验表明,流敏消谐装置在较短的消谐时间内可以将励磁涌流抑制在0.2 A以下,涌流抑制能力较压敏消谐装置优,可以解决因系统间歇性接地导致保险熔断、互感器炸裂的问题。Harmonic eliminator of voltage dependent resistance type is series between the neutral point of the prima⁃ry side of the inductive voltage transformers and the ground,whichis used to suppress the ferromagnetic resonance by applying a voltage across the device during the resonance process.This resonance suppression measure is prone to insurance fuses and inductive voltage transformers burst during the resonance process.This paper analyzes the cause of a burst failure of the inductive voltage transformers due to the intermittent grounding of the system,and proposes a PTC thermistor⁃based harmonic eliminator of current dependent resistance type device for the primary side of the in⁃ductive voltage transformers,and ferromagnetic resonance suppression is performed in the through⁃current state.Tests show that the harmonic eliminator of current dependent resistance type can suppress the excitation inrush cur⁃rent under 0.2 A in a short resonance elimination time,and the surge suppression ability is better than the harmonic eliminator of voltage dependent resistance type,which can solve the insurance fuses and inductive voltage transform⁃ers burst caused by the intermittent grounding of the system.

关 键 词：电磁式电压互感器 一次消谐装置 压敏消谐装置 流敏消谐装置 铁磁谐振 

分 类 号：TM451[电气工程—电器]