Method for positioning fault section of T-connection high-voltage power transmission line

The invention discloses a method for positioning a fault section of a T-connection high-voltage power transmission line, belongs to the relevant technical field of power transmission line fault positioning, and particularly relates to a method for judging a fault section by using power frequency current detected by a distributed type traveling wave fault positioning device. The method is characterized in that a power frequency current measurement unit is additionally arranged on an original distributed type traveling wave fault positioning device comprising a power frequency current measurement unit; the two power frequency current measurement units are respectively mounted on two branch lines of a T joint; a position of a fault point is subjected to section positioning according to change features of a current peak value and a phase within a period before and after a fault moment. By the adoption of the method, the problem of a false fault point positioned by conventional traveling waves can be solved, and by reliable and accurate measurement of power frequency fault current, the fault positioning reliability is effectively improved.