RF‐based location of partial discharge sources using received signal features

Abstract

Partial discharges (PDs) are symptomatic of some localised defects in the insulation system of electrical equipment. PD activity emits electrical pulses in the form of radio frequency (RF) signals which can be captured using appropriate sensors. The analysis of the measured RF signals facilitates localisation of PD. This study investigates the plausibility of using purely RF received signal features of PD pulses to locate PD at low cost. A localisation approach based on the analysis of these features has been developed, with the assumption that PDs generate unique RF spatial patterns due to the complexities and nonlinearities of RF propagation. In this approach, two distinct frequency bands which hold different PD information are exploited. PD location features are extracted from the main PD signal and the two sub-band signals. Correlation-based feature selection (CFS) is employed for feature selection and dimensionality reduction. Experimental results show that PD location can be inferred from the features of the PD pulses. The application of CFS to PD data reduces the memory/computational demand and improves localisation accuracy.

Intelligent learning approach for UHF partial discharge localisation in air‐insulated substations

“…In this simulation experiment, the effect caused by changing over the time signal amplitude was not considered. However, it can be reduced by the normalisation method when dealing with an actual PD [12]. The tests were conducted as follows.…”

“…However, the PD source localisation methods for these UHF sensor array systems are time‐difference based algorithms, such as time difference of arrival (TDOA) [9–11], which means a high‐speed (GS/s) synchronous sampling system is required. To reduce the hardware cost further, a UHF received signal strength indicator (RSSI) based PD source localisation method has been proposed to achieve a balance between localisation accuracy and cost [12–15].…”

“…In addition, it exhibits high environment adaptability. However, the requirement of a prebuilt RSSI fingerprint map of the off‐line stage makes it tedious to deploy it in existing substations [12–14]. With a change in the measuring environment, the fingerprint map needs to be rebuilt.…”

Fault early warning in air‐insulated substations by RSSI‐based angle of arrival estimation and monopole UHF wireless sensor array

“…The system is usually assembled in a vehicle considering its size and weight. According to [11,15], the localisation error is reported <2°. In comparison, the proposed method bears a quite lower cost since only peak detection of the UHF signal is a need.…”

“…Ultra-high frequency (UHF) electromagnetic wave has an advantage of high sensitivity and strong anti-interference [6][7][8][9]. A time delay estimation method of PD monitoring and localisation in airinsulated substation using the UHF antenna array was proposed in [10][11][12][13], which reduces the installation cost and maintenance work significantly. However, this kind of method requires sensors to have an accurate time synchronisation of nanosecond and a high sample rate of several gigahertz which leads to a high hardware cost and poor portability [14][15][16].…”