Power Cable Fault Research Articles

Instrumentation for the Detection and Locatiion of Incipient Faults on Power Cables

A description is given of the instrumentation being developed for the detection and location of incipient faults in power cables by the processing of the electromagnetic noise that appears at the power cable terminals. After a discussion of the basic concept, which involves a correlation technique, the implementation of the concept in the form of a microprocessor controlled, polarity coincidence type of correlator is described. Test results of the instrument with various types of noise sources are given. These include tests on a length of 15 kV class underground distribution cable with staged incipient faults. Some of these tests show that the instrumentation is capable of detecting and locating partial discharge noise on the cable with interesting precision.

Locating faults in power cables

Power cable fault locating is at times difficult due to a high initial fault resistance or an increase of resistance during the time locating is in progress. A method using a constant current transformer for reducing high initial resistance and preventing its increase, in connection with a short circuiting switch to generate signals for locating the fault, is discussed in this article. A practical assembly of this type of apparatus for cable fault locating is described and operating directions are included.

A power cable fault bridge

A power cable fault bridge