姜杰,赵广泉,孙小江,卢金奎,蔡明.基于信号注入法的铁磁谐振与单相接地故障辨识[J].电测与仪表,2012,49(3):46-49. JIANG Jie , ZHAO Guang-quan , SUN Xiao-jiang , LU Jin-kui , CAI Ming.Distinguish Ferroresonance from Single-phase Earth Fault Based on the Approach of Signal Injection[J].Electrical Measurement & Instrumentation,2012,49(3):46-49.
基于信号注入法的铁磁谐振与单相接地故障辨识
Distinguish Ferroresonance from Single-phase Earth Fault Based on the Approach of Signal Injection
In an isolated neutral point power system,potential transformer ferroresonance and single-phase earth fault are very frequent,and the phenomenon of them is similar,the zero-sequence voltage showing high for a long time.Because of the problem of distinguishing fundamental frequency ferroresonance from single-phase earth fault,the PT-resonance-eliminator and the fault-feeder detector could not tell the difference between two fault types well,they are apt to make the wrong judgments in some cases.The approach of signal injection is put forward by analyzing the difference of line-to-ground impedance between fundamental frequency ferroresonance and single-phase earth fault.As the injection current is fixed,it will produces different voltage to different fault types.This method is used to identify fundamental frequency ferroresonance from single-phase earth fault based on the above.Verification by simulation data reveals that the approach is right and effective.
