This paper presents the results of analysis of a solid dielectric’s influence on the phenomena associated with the signals emitted by surface partial discharges. Three types of electrode systems were tested, in which solid dielectrics made of pressboard, Teflon, and glass were used. The emission of such signals as radio waves in the Ultra high frequency (UHF) range and optical radiation was analyzed. The measurements were carried out in the insulation systems most commonly used in electrical power equipment, i.e., mineral oil and air. UHF and optical spectrophotometry methods were used to register the emitted signals. The obtained results indicate that the type of material from which the dielectric solid is made may have a potential impact on some ranges of emitted electromagnetic waves during the surface electrical discharges. The research topic undertaken is important in issues associated with high-voltage insulation systems and in particular with surface discharges, which are often the cause of their damage.

Results of a comparative analysis of two non-dimensional coefficients, calculated based on signals emitted by partial discharges (PD) are presented in the paper. The PD were generated using setups for modeling of three basic types of PD sources, which can occur in paper-oil insulation in power transformers. The following measuring methods were considered: electrical, ultra-high frequency, acoustic emission, and optical spectrophotometry. All measurements, for each of the PD-source configuration using the various methods, were conducted simultaneously in a laboratory under same measurement conditions. Based on the gathered results it was stated that it is possible to recognize the partial discharges form based on the non-dimensional coefficients, which differ in value for all of the considered methods except for the acoustic emission. The main contribution of the research performed lies in the simplicity of the applied signal processing procedure, which can be adopted to a device or system for diagnosis of partial discharges occurring in paper-oil insulation.

The stidy presents research results considering measurement and detection of electromagnetic radiation (EMR) generated by partial discharges (PDs) in the air and during breakdown. The key objective of the works was to develop a methodology of detection of ionising radiation generated by electrical discharges. This includes design of experimental setup for simulation of discharges under laboratory conditions and selection of appropriate measuring devices. For measurements of visible light and UV radiation, a HR‐4000 spectrophotometer was chosen. The high energy ionising radiation was detected by means of a scintillation counter by own production. The experimental studies involved registration of EMR emitted by both PD and electrical breakdowns of the measuring system for various point–point electrodes arrangements. Then, characteristic spectra were defined in bands from visible light, through UV to the X‐ray radiation frequencies. The use of high‐energy radiation detection for determining basic forms of discharges and the potential possibility of the detailed specification of their power balance are curtail achievements of the presented article. The other contributions lie in the simultaneously application of two independent discharge detection methods.

The subject matter of the study applies to determining the possibilities and indicating the scope of application of the analysis of optical spectra emitted by basic forms of electrical discharge in insulation oil, recorded with the use of the optical spectrophotometry method. The main objective of the experimental works was to select a group of descriptors typical of optical signals generated in systems modelling electrical discharge on the basis of which it would be possible to recognise their forms. The study presents the results of measurements and analyses conducted under laboratory conditions for three systems modelling electrical discharge in mineral oil under various technical conditions. The results presented in the study are the initial stage of research aimed at determining the suitability of descriptors describing optical radiation emitted by electrical discharge for identifying the type of defect of insulation systems in high‐voltage power devices.

The article presents research on the electric arc generated by AC current at different frequencies. The measurement procedure and system are described. Optical spectra of the generated arc in the air were recorded using a spectrophotometer. Optical spectra for five frequencies were obtained. The article also presents the energy balance of the components of the registered spectrum. The visible changes in the spectra that depend on the frequency of the AC current generating the electric arc can be significant to the diagnostics of gas insulators. The research presented in the article can be used in multiple areas of technology where an electric arc is used. The influence of the frequency of the current supplying the electric arc on the electromagnetic radiation spectrum in the area of light radiation emitted by the electric arc allows for the construction of systems that can shape the desired characteristics of the electric arc.

This paper presents the results of measurement and analysis of optical radiation emitted by a free burning electric arc. The aim was to determine the application possibilities of optical spectrophotometry for detection of electric arcs. The research works considered electric arc generated with a constant voltage supply between two copper electrodes in the air, carried out under laboratory conditions. A high resolution optical spectrophotometer was used for registration of optical radiation. The analyses involved determination of two dimensionless descriptors obtained for the gathered spectra. Moreover, for each of the registered intensity distributions, the energy values were calculated for three frequency ranges. Based on the measured signals, the possibility of application of spectrophotometry for the optical radiation analysis was confirmed. The analysis indicated that the most energy of optical radiation is detected for the range of 200–780 nm, while above 780 nm almost no optical energy is emitted. Spectrophotometric studies performed in the UV-NIR range are of interest since one can obtain information about the structural defects (at lower wavebands) or impurities and/or point defects (at low energies bands). It was also stated that the obtained descriptors may be applied for diagnosis and identification of electric arc purposes.