Network impulse response based-on fault location method for fault location in power distribution systems

摘要

This study proposes a new time-domain fault location method based on the impulse response (image) of a power system. The proposed algorithm captures an electrical image of the power system in normal operation by injecting a train of impulses. Following fault detection, an updated electrical image is acquired and compared with the normal operating image. The comparison between both images, in time domain, permits the estimation of the distance to the fault. The performance of the proposed method has been evaluated in a 20 kV distribution system modelled in power systems computer-aided design/electro-magnetic transient design and control (PSCAD/EMTDC). Moreover, laboratory and field tests in a 15 kV overhead line have been carried out to verify and validate model accuracy and performance. Results show a considerable improvement in the accuracy of fault distance estimation compared with existing algorithms. A relevant advantage of the proposed method is its high immunity to ground resistivity, fault resistance and fault type and location in the distribution system.