The invention discloses an electric
transmission line phase fault single-ended distance measuring method. The electric
transmission line phase fault single-ended distance measuring method includes the following steps of working out equivalent resistance through the
voltage between fault phases, the current between the fault phases, and the negative-sequence current between the fault phases at the electric
transmission line relay location, obtaining the
voltage of a phase fault point through the fact that the equivalent resistance is multiplied by the negative-sequence current between the fault phases, working out the real part of a ratio between the
voltage of the phase fault point and the
voltage drop of an electric transmission line of per unit length, obtaining the additional fault distance caused by a transition
resistor, and obtaining the fault distance from the electric transmission line
relay location to the phase fault point through the difference between the real part of the ratio between the voltage between fault phases and the
voltage drop of the electric transmission line of per unit length and the additional fault distance. The electric transmission line phase fault single-ended distance measuring method solves the problem that the transition
resistor influences the precision of electric transmission line phase fault single-ended distance measuring, has high distance measuring precision and is simple in distance
measuring principle. In addition, according to the electric transmission line phase fault single-ended distance measuring method, a program is easy to achieve, the fault distance is directly worked out without the need for application of search algorithms, distance measuring is fast, and the instantaneity is strong.