FAULT PROTECTION IN MIXED HIGH-VOLTAGE TRANSMISSION LINES

摘要

An improved method of fault protection in high-voltage power transmission lines (100) comprising multiple sections (103, 104) of different type, i.e., cable or overhead line, is provided. The method comprises determining a time difference At between a first time of arrival of a fault-induced (105) travelling wave at a first end (101 ) of the transmission line and a second time of arrival of the fault-induced (105) travelling wave at a second end (102) of the transmission line, comparing the measured time difference to a plurality pre-determined time differences Δtn, wherein each time difference Δt_n corresponds to a junction (101, 102, 106) between adjacent sections of the transmission line (100), and determining that the fault (105) occurred in section n_f (103) of the transmission line if Δt_nf Δt Δt_nf+1. Further, a fault protection device is provided.