Applications of a high frequency current transformer and air-core inductive devices for detecting a partial discharge location in a cable

This paper presents applications of partial discharge sensing devices for detecting a partial discharge location in a cable. Three devices are under investigated. The first type is a high frequency current transformer (HFCT), while other two types are air core inductive devices with different configuration. The high frequency current transformer is constructed from a ferromagnetic material core, and the winding conductor is in a single compensation form. The first air core inductive device is wound in a single compensation pattern, and uses the return winding in the form of a copper sheet. The second air core inductive device, differently, is in a counter wound compensation pattern. In experiments, a partial discharge sensing device is installed at one end of the cable. The standard pulse calibrator is employed to inject partial discharge pulses at the designated locations along the cable. The Time Domain Reflectometry technique (TDR), which is based on the travelling wave theory, is employed in calculating the partial discharge locations. It is found that these three current transducers can detect the partial discharge pulses, and with the algorithm, which is developed using the Time Domain Reflectometry, the partial discharge location along the cable can be identified accurately.