In view of failure of line selection due to weak fault characteristic information when then resonant grounding system is grounded through high resistance

a kind of tuning method in fault line selection is proposed. The zero sequence current feature of the system and anti-transition resistance ability of the propose dline selection proposal after the fault are analyzed in detail. It is found through adjusting detuning degree to change the zero-sequence current characteristics of the line that the zero sequence current variation direction for the faultand healthy line is opposite and the variation difference is obvious. The tuned fault line selection method is constructed by using the difference between the zero-sequence current variation characteristics of the fault line and the healthy line. It is shown by the simulation result that the method is accurate and reliable and

under high-resistance grounding

can identify the fault line as well as improvethe accuracy of line selection further.