Line Selection Device of Small Current Single-phase Grounding Fault Based on Integrative Line Selection Strategy

For the deficiency of single line selection principle, the paper proposed integrative line selection strategy, namely zero sequence admittance method, zero sequence susceptance increment method and zero sequence conductance method based on steady-state fault component, mutual integral of transient current based on transient-state fault componet. A line selection device for small current single-phase grounding fault was developed based on the above method. The line selection device can select different line selection algorithm according to different neutral grounding through keyboard, and realize integrative line selection based on steady-state and transient grounding fault. The experiment result showed that the line selection device is effective for high impedance grounding fault and arcing grounding fault.