Radiometric Location of Partial Discharge Sources on Energized High-Voltage Plant

Abstract

Partial discharges (PD) generate wideband radio frequency interference and, consequently, can be detected using radio receiving equipment. Due to the advances in ultra-high-speed sampling equipment, it is possible to accurately measure the propagation of the PD wavefront as it passes through a 4 element antenna array. From these measurements, the three-dimensional position of the PD source can be calculated using an iterative algorithm. The locating equipment is suitable for use within the vicinity of energized high-voltage plant and can locate sources up to 15 m from the array. Results are presented showing the location ability of the equipment under laboratory and field conditions. A significant advantage is the ability to detect PD sources in energized plant without the need for outages or electrical connections.

Inspection of Wave Propagation Due to Partial Discharge Occurring in Current Transformer Using 3-D Finite Difference Time Domain Based Technique

“…The electromagnetic radiation is related to the rate of change of current and the structure and connections of the radiated. For this reason PD can be detected using wideband radiometric antennas [10], [11]. The challenges of PD detection circuits are the design of proper sensors (antennas) capable of signal detection in broadband range and the signal interpretation circuits [12], [13].…”

The use of radiometric partial discharge location equipment in distribution substations

“…The time delay is measured from the initial wavefronts of the recorded signals. The method used, described in detail in [3], is possible due to the fact that partial discharges emit impulsive radio frequency signals having fast-rising wavefronts (e.g. Figure 3) that may be used to accurately estimate the time-difference of arrival between synchronously sampled signals.…”

Separation of sources in radiofrequency measurements of partial discharges using time–power ratio maps

“…The use of EM sensors can be applied to any type of insulating material with the advantage of not needing a galvanic connection to the equipment when compared with capacitive and inductive sensors. Moreover, the nature of an insulating dielectric can be related to the frequency band emitted by the PD, being their energy higher at high frequencies for stronger dielectrics than for weaker insulations, Moore et al (2005).…”