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Vol. 18 (2015 year), No. 1
Vlasov A. B.
On properties of laser diodes at cryogenic temperatures
The experimental analysis of physical and spectral features of laser diodes at natural and cryogenic temperatures has been carried out
(in Russian, стр.3, fig. 4, tables. 0, ref 4, Adobe PDF, Adobe PDF 0 Kb)
Vol. 18 (2015 year), No. 1
Remezovsky V. M., Vlasov A. B., Mukhalyov V. A.
The method for controlling electric machine parameters
based on the analysis of starting currents
The theoretical and experimental analysis of the electric machine technical condition by studying activate currents has been carried out. It has been shown that by means of express-methods it is possible to estimate the electric engine parameters with sufficient degree of accuracy
(in Russian, стр.6, fig. 3, tables. 3, ref 3, Adobe PDF, Adobe PDF 0 Kb)
Vol. 18 (2015 year), No. 4
Vlasov A. B., Vlasova S. V., Alloyarov K. B., Muhalev V. A.
The method of controlling the properties of rubber insulation of cables
The method of controlling the properties of rubber insulation of cables allowing evaluation of the technical condition of the insulation during aging has been developed. The method is based on measuring the hardness of the insulation during operation
(in Russian, стр.10, fig. 14, tables. 1, ref 4, Adobe PDF, Adobe PDF 0 Kb)
Vol. 20 (2017 year), No. 4, DOI: 10.21443/1560-9278-2017-20-4
Vlasova S. V., Vlasov A. B., Shapochkin P. Yu.
Features of laser diodes' radiation in different temperature intervals
In the literature there is practically no information on the change in the characteristics of the emission spectrum of industrial semiconductor laser diodes in a wide range of temperatures, including cryogenic temperatures. Nevertheless, this information is decisive when choosing specific laser diodes for industrial devices. An experimental study of features of the emission spectra of laser semiconductor diodes in the temperature range 50–300 K has been conducted. The material used in the laser diodes' manufacture is a compound based on the solid quaternary AlGaInP solution. The radiation spectrum has been investigated using a monochromator MDR-23 with a CCD detector installed. The study has proved that the temperature of the laser diode operation determines the nature of the radiation spectrum, in particular the predominance of stimulated or induced radiation has taken place, the range of wavelengths of radiation changes as well. It is believed that in the temperature range from 50 to 300 K in the volume of the laser diode material some processes are realized, as a result of which the value of the forbidden band width changes, it decreases by approximately 4.2–4.5 % from the value corresponding to the temperature of 50 K. The calculation of the value of the temperature coefficient of the change in the forbidden band width has shown that in the temperature range from 50 to 300 K the meaning of ? varies in absolute value by 2–3 times. A new experimental method for determining ionization energies of exciton levels has been proposed. It is of practical use for monitoring the electro-physical parameters of semiconductor materials used in the manufacture of industrial semiconductor lasers. The advantage of the proposed method is the ability to obtain qualitative and quantitative information about the exciton spectrum of the laser diode material directly in the region of the p–n-junction where the laser radiation is formed.
(in English, стр.8, fig. 3, tables. 2, ref 6, Adobe PDF, Adobe PDF 0 Kb)
Vol. 21 (2018 year), No. 4, DOI: 10.21443/1560-9278-2018-21-4
Vlasov A. B.
Method for determining the quality of cable inlets sealant using infrared thermography
The results of applying the quality control method to cable inlets sealant (hermetic lead, sealed lead-in, cable boxes) have been considered. Cable inlets are designed to prevent the spread of fire in adjacent areas through cable sealing boxes, e. g. on sea vessels. The known methods for determining the quality of cable inlets sealant are laborious and in some cases even impossible to implement when used on sea vessels. This applies to cases when the room through which the cables pass is being poured with water and some pressure stipulated by the ship specifications is being created there, or when the air pressure increases in such rooms. The novelty of the present method lies in the fact that it is based on the principles of pulsed thermal non-destructive testing of a material. The FLUKE thermovision camera Ti400 has been used as a technical means recording the temperature field of the sealant surface after exposure to a thermal pulse. The method approbation has indicated that thermal non-destructive testing can be used to detect relatively small penetration defects in the sealant volume.
(in Russian, стр.5, fig. 5, tables. 0, ref 12, adobePDF, adobePDF 0 Kb)
Vol. 22 (2019 year), No. 4, DOI: 10.21443/1560-9278-2019-22-4
Vlasov A. B., Alloyarov K. B.
Features of implementing the quantitative thermographic diagnostics method while introducing digital technology
The development of non-destructive testing methods for power equipment including methods of thermal imaging diagnostics is relevant in view of the tasks set for implementing the concept of "Digital Transformation 2030". The paper provides a review and theoretical analysis of the problems that arise during the quantitative thermographic diagnostics of electrical equipment. On the example of analysis of the thermal imaging tests of heating a contact compound during electric current flow, the advantages of the method and the disadvantages of the existing approaches have been considered. It has been shown that with the existing recommendations for processing thermal imaging tests, in particular, "RD 34.45-51.300-97. Scope and norms of testing electrical equipment", forecasting and expert assessment of the thermal state lead to significant errors. The data of numerous diagnostic parameters taken into account in the process of thermal imaging diagnostics have been evaluated, namely: current load, geometric and thermophysical parameters of the object and the environment, emissivity, wind speed and others. Taking into account the electrophysical parameters of an object, the features of its structure allows for an adequate expert assessment and data reduction to a single criterion; this makes it possible to compare the results of various tests, to accumulate a data bank, the prospect of which is to calculate reliability indicators and recommendations for improving the technical base of power engineering. The similar approach headed by the analysis of quantitative data accumulated during thermal imaging tests, and a comparative analysis of the data of other diagnostic methods, will make it possible to implement and expand the capabilities of the method when developing digital technologies.
(in Russian, стр.11, fig. 9, tables. 0, ref 13, AdobePDF, AdobePDF 0 Kb)
Vol. 23 (2020 year), No. 4, DOI: 10.21443/1560-9278-2020-23-4
Vlasov A. B., Buev S. A.
The estimation of ship cable condition by the means of measuring its insulation characteristics
Timely detection of defects in electrical equipment and cable network is required for the ensuring the fire safety of a modern marine vessel. The method of continuous monitoring of the resistance value of cable insulation is not very informative and is not applicable for assessing the service life of cables and predicting their replacement during operation and repair. Currently the problem of developing modern non-destructive methods of insulation control is very urgent in order to determine the operability of the cable, search for diagnostic parameters characterizing the state of insulation during prolonged aging, as well as the introduction of traditional methods of diagnostics of electrical equipment that have shown their effectiveness at the facilities of the coastal infrastructure. A promising solution for this problem is a method for monitoring the values of the tangent of the dielectric loss angle tgδ of cable insulation using devices that allow registering parameters with high accuracy. In this study the determination of changes in the parameters of a ship cable subjected to accelerated thermal aging at temperatures 120–130 °C has been made. The tgδ measurements of the cable sheath have been carried out using the Tangent-2000 insulation meter. The tests have shown that aging of cable hose insulation is accompanied by a non-linear change in tgδ at certain values of the tangent of dielectric loss angle, visible cracks appear indicating the onset of an emergency condition of the cable. The nature of the change in the parameter tgδ is explained by the occurrence of reactions of oxidative dehydrochlorination of polychloroprene in the process of thermal aging of insulation and changes in its mass. Thus, the tangent of the dielectric loss angle can be one of the diagnostic parameters for assessing the state of the insulation of the ship's cable and predicting its service life.
(in Russian, стр.9, fig. 8, tables. 3, ref 11, AdobePDF, AdobePDF 0 Kb)
Vol. 25 (2022 year), No. 4, DOI: 10.21443/1560-9278-2022-25-4
Vlasov A. B., Buev S. A., Kucherenko V. V., Urvantsev V. I.
Analysis of the traction motor electrical parameters of the trolleybus
The technical equipment of modern trolleybuses (increased power of traction motors, regenerative-rheostatic braking, anti-slip and anti-lock systems, an on-board computer for monitoring and controlling the operation of the traction drive, GLONASS satellite systems, Internet access) increases the requirements for the quality of electrical energy and the electromagnetic compatibility of the installed equipment. In the course of the study, the electrical performance of the trolleybus traction asynchronous motor (voltage, current, voltage sinusoidal shape, total coefficient of harmonic voltage components) has been analyzed. Due to difficulties in the supply of foreign electrical equipment, primarily power electronics elements used to control the operation of the traction motor, there is an increasing need to improve measures for the maintenance of trolleybuses to increase the reliability and uptime of the equipment. The advantages of using the methods of quantitative thermography, analysis of the quality of electrical energy and control of the hardness of cable insulation have been experimentally established. With the help of an analyzer of electric energy quality, measurements of the quantitative indicators of the operation of the electric motor have been carried out; the thermal imager has been used to assess the thermal state of contact connections and cable routes. The use of new diagnostic methods is of particular relevance in the course of continuous long-term operation of electric transport in the Far North.
(in Russian, стр.10, fig. 8, tables. 0, ref 13, AdobePDF, AdobePDF 0 Kb)