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Characteristic of Surface Partial Discharges Measured with Ultraviolet Camera

100%
Frącz P., Zmarzły D., Boczar T.
Acta Physica Polonica A
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2015
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vol. 127
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issue 3
715-718
EN
The performed research works consider diagnosis of different models of support and bushing insulators. Insulator systems undergo aging processes, which causes deterioration of the insulating properties. In addition, pollutants that accumulate on the surface of high voltage insulators cause further reduction of the insulation properties. Presence of pollutants and high humidity level cause formation of conductive paths, which acts as a source of partial discharges. Presented results depict optical signals, recorded by ultraviolet camera, which were emitted by surface partial discharges occurring on different insulator models. In particular, the effect of the relative value of camera sensitivity on the number of surface partial discharges counts was evaluated. In addition, analysis of the effect of the surface partial discharges generation time on registered counts number was made. The experiments were performed at a constant voltage of 0.9U_{p} and for a distance between the HV electrode and GND equal to 10 cm. The experimental study lasted over a period of 30 min, while the measurement steps were done every minute.
2
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Studies on Infrasound Noise Generated by Operation οf Low-Power Wind Turbine

100%
Pierzga R., Boczar T., Wotzka D., Zmarzły D.
Acta Physica Polonica A
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2013
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vol. 124
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issue 3
542-545
EN
Subject matter of this paper deals with issues of the environmental impact of infrasound noise associated with operation of low-power wind turbines. It is now the current and relevant problem for both the cognitive and utilitarian standpoint. There is now a considerable growth in the number of such installations in Poland, Europe and in the world, due to the possibility of locating them on existing building roofs in heavily urbanized areas, and without having to build additional supporting structures. As part of the study, measurements of low frequency acoustic signals generated during operation of micro turbine equipped with a rotor of vertical axis of rotation relative to the wind direction have been performed. Analyses were carried out in order to determine the impact of wind speed and selected meteorological parameters on the level of infrasound signals emitted by the test turbine. In addition, frequency analysis of the recorded signals was performed. Then, the obtained results were subjected to comparative analysis. In summary, the achieved results were referred to the limits of sound pressure intensity level of infrasound signals as specified for the working environment in accordance with the Polish Standard PN-Z-01338.
3
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Analysis of Acoustic Wave Propagation in a Power Transformer Model

100%
Wotzka D., Boczar T., Zmarzły D.
Acta Physica Polonica A
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2009
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vol. 116
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issue 3
428-431
EN
Analyses of acoustic wave propagation in a model power transformer are presented in the paper. The acoustic wave is induced by partial discharges that are simulated at predefined coordinates in the core and winding. Propagation of the numerical calculated acoustic wave is analyzed within the transient state. Achieved results indicate that the space and time distributions of the acoustic pressure depend on the induction position. Furthermore, a greater pressure gradient is observed in domains with higher speed of sound while the largest amplitude occurs at the vicinity of the induction position.
4
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Analysis of Ionizing Radiation Generated by Partial Discharges

100%
Zmarzły D., Nagi Ł., Borucki S., Boczar T.
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vol. 125
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issue 6
1377-1379
EN
This paper presents the preliminary results of the performed experiment, based on common phenomenon of partial discharges. A simple Geiger-Muller counter (DP-66M) was used for measurement of a dose of ionizing radiation, which is accompanied by partial discharges. Values from which the radiation intensity was dependent could be controlled individually: the distance between measurer and source, as well as the voltage generating partial discharges. The obtained results indicate that in the examined phenomenon, significant dose of X-ray radiation is present. According to the Kramers-Kulenkampff theory, it depends also on the atomic number of elements involved. Using MATLAB software, the obtained data were compiled to develop suitable theory for further research study. There was also implemented fuzzification for the fuzzy logic, and the effect was the capability of forecasting radiation doses according to the fixed variables for a given material, where partial discharges were generated.
5
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Numerical Simulation of Acoustic Wave Propagating in a Spherical Object Filled with Insulating Oil

100%
Wotzka D., Zmarzły D., Boczar T.
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issue 6
1272-1275
EN
Results of a numerical simulation of an acoustic wave that propagates in a spherical object filled with insulating oil are presented in the paper. The sinusoidal acoustic wave is generated by an electro-acoustic transducer mounted in the middle of the object. Presented results depict acoustic pressure distribution within the transient and the steady states in a two-dimensional object. Furthermore, comparison of short time simulations adapting different mesh element size is presented.
6
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Acoustic Spectra of Ultrasound Induced Cavitations in Insulating Oils

100%
Szmechta M., Zmarzły D., Boczar T., Lorenc M.
Acta Physica Polonica A
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2008
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vol. 114
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issue 6A
A-231-A-238
EN
Acoustic emission measurement results of acoustically induced cavitation bubbles in insulating oil are presented in this paper. Spectral analysis of acquired by a broadband transducer acoustic emission signals is proposed as a diagnostic tool for estimation of aging properties of mineral insulating oils. The article describes the main parts of the designed and built measurement apparatus used for acoustic cavitation investigation in insulating oils. In this note representative results of the experimental data taken from the apparatus are shown.
7
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The Use of 3D Modeling in the Diagnosis of Power Capacitors with Acoustic Emission Method

100%
Boczar T., Błachowicz A., Borucki S., Zmarzły D.
Acta Physica Polonica A
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2012
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vol. 122
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issue 5
796-799
EN
The article presents the issue modelling the partial discharge phenomenon in engineering and scientific environments using hardware-based computer cluster. The authors present the results of research work on the phenomenon of acoustic emission from partial discharge occurring in power capacitors for power factor correction. The work includes the issues presentation and explanation of solutions enabling to create 3D spatial model of power capacitor. The authors proposed a simplified model of an acoustic test object aimed at improving the process of calculating the results.
8
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Analysis of Optical Radiation Generated by Electrical Discharges on Support Insulator

100%
Frącz P., Boczar T., Zmarzły D., Szczyrba T.
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EN
Subject of the paper concerns determination of the feasibility and indication of the application scope of optical spectroscopy methods in the diagnosis of high-voltage insulators. Results of measurements of optical radiation emitted by partial and complete electrical discharges occurring on a support insulator model placed in air are presented in the paper. Registration was performed using a spectrophotometer, enabling for measurement of optical radiation in the range from 200 to 1800 nm. The primary objective of the laboratory tests was to evaluate the impact of supply voltage changes in the range from 0 to 60 kV on the intensity and spectral character of the optical radiation emitted by electric discharges generated on the porcelain insulation surface of the support insulator. In the scope of studies analyzes of the effects of voltage changes on the obtained spectral wave forms were performed, whereby voltage increase and reduction was examined separately. Additionally, measurements and analyzes carried out included impact estimation of the time period as the voltage was applied to the high-voltage electrodes on the course of optical phenomena related to the generation of electrical discharges.
9
Content available remote

Results of Optical Signals Analyses Emitted by Electrical Discharges Recorded with UV Camera

88%
Frącz P., Boczar T., Borucki S., Cichoń A., Zmarzły D.
Acta Physica Polonica A
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2012
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vol. 122
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issue 5
814-817
EN
In the article results of measurements and analyses of the optical signals emitted by electrical surface partial discharges occurring on bushing and post insulators, recorded with UV camera during tests under laboratory conditions are presented. The carried out research was to determine the effect of the distance between the insulator's electrodes and the voltage value on the number of partial discharges.
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