The composition and content of dissolved gases in transformer oil are closely related to the type faults severity potential hazards. Dissolved gas analysis (DGA) insulating is an important way monitor state equipment. CO, CH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> , C xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> H one oil. Based on density functional theory, optimal adsorption site transition metal atom Pt surface WSe...

Abstract In this paper we investigated SF 6 decomposition behaviour of typical insulation defects in gas‐solid insulated converter transformer valve‐side bushing under partial discharge (PD). Additionally, compared the results with that gas switchgear (GIS). The indicated varies type. For metal protrusion defects, proportion ranking CO 2 and SO can be related to whether needle tip is wrapped epoxy resin‐impregnated (ERIP). carbon‐containing products much higher contamination defect than...

A general force field methodology is developed for description of molecular interactions in carbon-based materials. The method makes use existing parameters potential functions $s{p}^{2}$ and $s{p}^{3}$ carbons allows accurate representation forces curved carbon environment. are explicitly curvature site dependent. proposed approach was used dynamics (MD) simulations hydrogen adsorption single-walled nanotubes (SWNTs). results reveal significant nanotube deformations the calculated energies...

In locating a transformer partial discharge (PD) source, there is large fluctuation error in the z ‐coordinate of location, which results with planar layout ultrahigh‐frequency (UHF) antenna sensors. For error, this paper first theoretically analyzes reason. According to theoretical analysis results, ladder‐wise calculation method PD source proposed: first, x ‐ and y ‐coordinates are calculated, then univariate equation f ( ) derived, obtained by ). Finally, positioning effect for verified...

Gas detection based on photoacoustic (PA) spectroscopy has attracted extensive attention due to high sensitivity and portability. Herein, achieve the simultaneously of transformer oil carbide gases, C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> H CO, a gas-detection system one cantilever beam sensor single-pass PA cell was proposed. The infrared light beams were coupled by coarse wavelength division multiplexer (CWDM) fiber coupler,...

The related regulations for electric power industry stipulate that CO gas is an important component to be detected when analyzing the composition of SF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> equipment. In this study, based on photoacoustic spectroscopy technology, quantitative detection carried out. First, in order avoid cross-interference effects other gases CO, characteristic absorption spectrum 4291.5 cm <sup...

A theoretical study of the rotational dynamics H2 molecules trapped in interstitial channels a carbon nanotube bundle is presented. The potential used this modeled as sum atom–atom (C–H) van der Waals interactions and electrostatic molecule with surrounding nanotubes. energy spectra calculated using product wave function, where coupling between translational modes treated mean-field manner. molecular simulation was performed for estimating hydrogen barrier. Both calculations results reveal...

The large-scale power transformer gap leakage electromagnetic wave partial discharge detection method belongs to the external UHF method. This can perform insulation on that is running without any modification of transformer, and principle simple convenient use. We have studied reliability propagation characteristics. However, this requires sensors in same plane. When performing PD localization, it has shortcomings large positioning error easy deviation results due on-site noise pollution....

Sulfur hexafluoride (SF6) is commonly used in gas insulated switchgears (GIS) as an insulating medium. When local overheating or partial discharge occurs GIS, SF6 may be decomposed into various products including CO. In this paper, based on the photoacoustic (PA) effect of molecules, infrared absorption line at 6380.318 cm−1 was chosen target line. An laser with a center wavelength 1567 nm light source, and cantilever enhanced PA detector sensor; then, experimental platform constructed. The...

Increasing the optical length of photoacoustic spectroscopy cell can enhance signal, but current research often focuses on increasing number reflections, selection (PAC) and relationship between reflections PAC are still relatively unstudied.This paper chooses to reflect laser once in structure cylindrical study.The experimental results show that 125 mm has best detection performance; increase (PA) signal increases with lens reflectivity, is negatively correlated cell; then, simulation model...

Cantilever enhanced photoacoustic spectroscopy, as a novel gas content detection method in the maintenance of power equipment, has attracted much studies due to its high sensitivity and convince integration. While up now, there is less quantitative analysis on free end deformation cantilever under different sound wave pressure, which hinders design application device. In this paper, distribution characteristics pressure insides pool along with were studied through experiment simulation...

Abstract Gas detection has become an indispensable part of the power equipment maintenance. Because many advantages, cantilever enhanced photoacoustic(PA) spectroscopy was studied by researchers. In this paper, with help Finite Element Method (FEM) simulations commercial software COMSOL, we have analyzed distribution sound pressure inside gas cell, in addition, relationship between Young’s modulus and size beam its deformation, eigen-frequencies were also obtained. Besides, performed...