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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. 24 (2021 year), No. 4, DOI: 10.21443/1560-9278-2021-24-4

Buev S. A.
Analysis of XLPE cable parameters subject to thermo aging

Modern marine vessels use electrically driven rudders; cruise liners, gas carriers, tankers are equipped with Azipod systems manufactured by the Swedish-Swiss company ABB. Gondola-type propellers make it possible to break ice when the vessel is moving astern, therefore such vessels are used for work on the Northern Sea Route, in particular, when working on the Yamal LNG project. The 22MW Azipod propulsion system rotates 360° and enables difficult maneuvering without the assistance of tugs. When operating such propellers, powerful diesel generators are installed on the ship. For the transmission of electricity, ship cables are used, which are subject to increased requirements that meet the standard of the International Electrotechnical Commission. Modern marine vessels are equipped with XLPE or EPDM insulated cable lines; industrial production of these cables is carried out in the Russian Federation. In the course of the study, a method for auditing the state of insulation has been considered based on an assessment of the change in the tangent of the angle of dielectric losses in the process of thermal aging of the cable of the PvBPng(A)-HF brand. Measurements of the tangent of the dielectric losses' angle have been carried out with a Tangens-2000 insulation parameter meter.

(in Russian, стр.9, fig. 5, tables. 2, ref 13, 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)