A new method for fault line selection based on correlation between zero-sequence voltage in bus and zero-sequence current in feeders

It is difficult to select the fault line due to the weak current when the single-phase grounding fault occurs in the resonant grounding system. A new method based on correlation between zero-sequence voltage in bus and zero-sequence current in feeders is proposed in this paper. The correlation coefficient is less than zero because the polarity of zero-sequence voltage and zero-sequence current is opposite in fault line, and correlation coefficient is large than zero because the polarity in sound line is same. Therefore, the feeder what corresponding to the minimum correlation coefficient is the fault line. Most simulation results show that in resonant grounding system, compared with the integrated correlation coefficient analysis between pure fault components of zero-sequence current from every line, this method can be applied to select fault line more better, and misjudgment will not be caused.(1)