On small current grounding system in single-phase grounding fault line selection based on DSP

The fault mechanism of small current grounding system in single-phase grounding is discussed, and the principle of fault line selection of transient component on faulty phase current is indicated. By the design of hardware and software, it is proved the amplitudes summation of zero sequence transition current between fault line and healthy lines makes a big difference in the feature band. The analysis of the system simulation shows the area of zero sequence transition current on fault line in the spectrum is the largest. Therefore, the application of small current grounding system in single-phase grounding fault line selection based on DSP is an advanced novel method which can distinguish between fault line and healthy lines effectively and accurately.