Comparative investigations of PD behaviour on an artificial accessory failure under medium test voltage AC, damped AC (DAC) and 0,1-Hz-VLF

Abstract:
In previous investigations, the artificial accessory failure by omitting the field control tube at the end of an MV cable was evaluated in terms of reproducibility and PD behaviour. Since this arrangement corresponds to a real failure type, and may occur, e.g. in the case of bad workmanship, it is of considerable interest how this type of failure can be detected by the established test voltage forms. For this purpose, the cable specimens are stressed with different test voltage forms like 50-Hz-AC, DAC and 0,1-Hz-VLF. The focus of this investigation is laid on the partial discharge characteristics under the different voltage forms.