Application and Monitoring of SF_6 Gas Insulated NGR (Neutral Grounding Resistor) Using Ceramics Resistors

摘要

Since ceramics resistor type NGR (Neutral Grounding Resistor) have been developed as new materials for power equipment, about 15 years have been passed. This paper describes cumulative application records of ceramics resistor type SF_6 gas insulated NGR and typical construction of 22kV, 66kV, 110kV NGR, and monitoring methods measuring residual leakage current of 110kV NGR depending on neutral unbalance voltage of power transformers and using thermal detection devices of ceramics resistors of 66kV NGR.