Fault detection system of power distribution network

The invention discloses a fault detection system of a power distribution network. The method comprises the steps that a data monitoring device is arranged in a power distribution network and used fordetecting a current in the power distribution network in real time; an information storage device is connected with the data monitoring device and used for generating a high-frequency signal and injecting the high-frequency signal into the power distribution network under the conditions that the current in the power distribution network rises to a preset threshold value and the duration reaches apreset duration; a fault detection device is arranged in the power distribution network and used for determining that the power distribution network breaks down and sending the current containing thehigh-frequency signal to the positioning device under the condition that it is detected that the current in the power distribution network contains the high-frequency signal; and a positioning deviceis used for processing the c