The application of fiber optic distributed temperature sensor to fault detection of XLPE insulated underground cable

If a fault occurs in an underground power cable it is necessary to find the fault point as quickly and accurately as possible. Although Murray loop method and pulse radar method have been extensively used for cable fault locating, the fault line needs to be removed from service and connected to detection equipment, which will take much time and effort. In the present paper, a new fault location method, which integrates fiber optic distributed temperature (FODT) sensor into cable, is introduced. The FODT sensor, which is applied to fault detection of XLPE insulated underground cable in resistance grounded power system, can find fault point immediately. The maximum detection distance, distance resolution and processing time for fault location are 10 km, 1 m and 30 s respectively.