A Novel Scheme of Single-Line-Grounded-Fault Detection and Its Practical Implementation for Non-Effective Grounded System

Manual isolation of transmission line so far has been a common way for single-line-grounded-fault detection in non-effective grounded system. However, in practice, due to factors such as insufficient selection criterion and poor function, the line selection accuracy is not high and the application effect is not good as expected. This paper proposes a novel scheme of grounded-fault line detection which can selectively and sequentially perform line trip by dynamic weighed line selection and automatic sequential isolation. The proposed method can reduce manual participation, alleviate operating personnel work pressure and consequently improve the efficiency of fault isolation. Besides, the proposed scheme can shorten the duration of single-phase grounded fault and effectively reduce the hidden human safety risk.