程乐峰,殷林飞.基于变频信号注入原理的防带地线合闸检测装置设计[J].电测与仪表,2016,53(21):. Cheng Lefeng,Yin Linfei.Development of detector for anti-closing with grounding wire based on variable frequency signal injection principle[J].Electrical Measurement & Instrumentation,2016,53(21):.
基于变频信号注入原理的防带地线合闸检测装置设计
Development of detector for anti-closing with grounding wire based on variable frequency signal injection principle
Aimed at problems of temporary hanged grounding wire detection during lines maintenance or rebuilding work of distribution network in 10 kV and under the voltage grade, a detection method based on variable frequency injection principle was studied, and a detector for anti-closing with grounding wire was developed based on DSP2812, the variable voltage signal was produced and injected into the detection loop circuit, which was composed of detector, distribution line, grounding wire and the earth, etc. Three-phase voltage and current signals were sampled, and after conditioning, were transmitted into CPU for comprehensive analysis, which could detect the wires in three-phase, two-phase and single-phase grounding situations, as well as no grounding and inter-phase short connection situations. The detector was modular design with high speed data processing chip, and in which the FFT algorithm was used to resolve the fundamental wave and harmonic, can availably judge the useful signals, and the intensity of inductive signal exists in wires. It is proved from the field test that the vicious accident of “closing with grounding wire” can be avoided in usage of the designed detector and which has a certain reference value.
