Power line fault location method, device and system

The invention discloses a power line fault location method, a device and a system. A power line includes multiple branches. The power line fault location method comprises the following steps: acquiring the time when faulty traveling wave is detected on each of the multiple branches; judging whether the time for detecting the faulty traveling wave is the same for the multiple branches; determining that the fault point of the power line is in an area where the intersection of the multiple branches is located if judging that the time for detecting the faulty traveling wave is the same for the multiple branches; and determining that the fault point of the power line is on the branch on which faulty traveling wave is detected first if judging that the time for detecting the faulty traveling wave is not the same for the multiple branches, wherein the distance between faulty traveling wave detection devices on the multiple branches and the intersection is the same. By adopting the method, the device and the system of the invention, the problem that the position of a fault point of a line cannot be found accurately in the prior art is solved, and an effect of accurate line fault point finding is achieved.