Pinpointing Partial Discharge in Medium Voltage Bus Duct; Recognize, Repair, Re-Energize: Copyright Material IEEE, Paper No. PCIC- 2018–36

Partial Discharge (PD) can be a characteristic of incipient failure of bus duct and may be used to detect early deterioration of insulation. Bus duct uses a non-uniform insulation system that relies on air and solid dielectric materials to achieve its dielectric requirements. This insulation system can be modeled as a series/parallel circuit and is susceptible to PD. Location identification of PD could contribute to proactively preventing an arc fault. This paper presents a time-correlated PD measurement acquired through an array of radio frequency antennas within medium voltage bus ducting of various designs. The research presented artificially recreates faults experienced in the field, created in laboratory environment under controlled conditions on medium voltage bus duct. A comparison of varying types of PD will be introduced and a technique developed to automatically detect and pinpoint the position based on the time delay of the measured RF signal as measured through tuned antennas. Bus duct equipped with such monitoring is shown to be a useful detection channel capable of accurate detection and localization over large sections of bus.