Spatial Spectral Characteristics of Partial Discharge with Different Electrode Models

Abstract

In this paper, the spatial spectral characteristics of partial discharge (PD) under different electrode models are mainly studied. In the initial corona discharge stage, the emission spectrum is mainly emitted by the N2(C3IIu→B3IIg) energy level transition of the N2 second positive band system. The spectrum is in the ultraviolet range of 294–436 nm, and its main peak is at 337 nm. The streamer discharge stage spectrum is mainly emitted by the energy level transition of the second positive band system of N2, N+, NO, and O+ and the first positive band system of N2(B3IIg→A3Σu+). In the gap of different polarity electrodes, the ultraviolet spectrum content near the positive polarity is more abundant. The UV spectra ranges are 202–225 nm and 229–292 nm, respectively. The discharge of the needle–sphere system is more intense in visible light and near-infrared light, with peaks at 500 nm and 777 nm, respectively. In addition, the PD process based on the finite element method is simulated by COMSOL Multiphysics software. The simulation results show that the distribution of high-energy electron density varies with the electrode spacing and discharge model. The influence of particle energy level transition on the spatial spectral characteristics of PD is verified. This work provides important insights and possibilities for future fluorescent fiberoptic sensing and positioning for spatial PD detection and positioning using spectral characteristic peaks as detection quantities or excitations.

Optical signals measurement of discharge plasma in air switch cabinet using a fluorescent optical fiber as the sensor

“…Partial discharge (PD) detection is an important task for power workers, which can be used to monitor the insulation condition inside the switch cabinet. Researches have shown that the type and discharge quantity can be inferred by extracting the key parameters of the PD signals, thus enabling the diagnosis of the type and severity of internal insulation defects [3][4][5][6]. However, the conventional PD detection methods, such as the ultrasound method and the ultra-high frequency (UHF) method [7][8][9][10], are not applicable to switch cabinets.…”