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Vol. 18 (2015 year), No. 4

Burtsev A. V., Nevretdinov Yu. M., Fastiy G. P.
Results of storm activity registration in the Kola Peninsula

Results of storm activity registration processing in the Kola Peninsula during 2013-2014 have been given. Considerable fluctuations of storm activity and unevenness of lightning discharges distribution across the region territory have been noted. It has been proposed to use a cloud-to-ground discharge density indicator taking into account their distribution in the region at an assessment of lightning protection efficiency of power generation facilities in areas with low thunder-storms intensity

(in Russian, стр.10, fig. 8, tables. 2, ref 10, Adobe PDF, Adobe PDF 0 Kb)

Vol. 20 (2017 year), No. 4, DOI: 10.21443/1560-9278-2017-20-4

Fastiy G. P., Burtsev A. V., Karpov A. S., Yaroshevich V. V., Tokareva E. A.
Analysis of operating conditions of the voltage transformer

In electrical networks, constant monitoring of the electrical equipment operation is necessary. To accomplish this task, current transformers and voltage transformers (VT) are used, on which the accuracy of electrical measurements, electricity metering, and the reliability of the emergency control system depend. The results of the analysis of the conditions for forming the magnetization of a voltage transformer in the mode with unilateral connection of overhead transmission lines, as well as variants of violations in the 110 kV network that may exist for a relatively long time have been presented. It should be noted that the considered network has its own peculiarities: the overhead transmission lines connected in series have a significant length and a low level of load, which may be a condition for the appearance of a transmission lines capacitive effect (the Ferranti effect), the latter can cause overvoltage. Overvoltage occurs when the operating modes are temporary in terms of operation, adverse combinations of network parameters take place, and can continue until the circuit and network modes change. Most often they appear in asymmetric modes, with short circuits to ground, etc. Asymmetric modes caused by incomplete-phase commutations and wire breaks on the overhead line, as well as wire breaks with subsequent disconnection of power transformers that can affect the voltage level on the VT have been considered. The possibility of VT magnetizing with a prolonged voltage rise in symmetric modes, namely, the manifestation of the Ferranti effect with various loads at substations up to complete switching-off and power transformers switching off has been investigated. The analysis of the measuring voltage transformer operating conditions has been based on materials provided by the "Kolenergo" services.

(in English, стр.9, fig. 4, tables. 5, ref 4, Adobe PDF, Adobe PDF 0 Kb)

Vol. 22 (2019 year), No. 4, DOI: 10.21443/1560-9278-2019-22-4

Burtsev A. V.
Model of an analytical system for damage searching on power lines due to lightning discharges

The problem of searching for damage on overhead lines due to a lightning discharge is relevant for consumers of electricity and its suppliers. A direct lightning strike into power line elements leads to the destruction of insulators, breakage of wires and cables, and a consumer disconnection. The main task of the maintenance staff is to search for damage that occurs after a lightning discharge. Usually, special devices are used, they are installed in substations and based on the wave method, the visual method is also used. The paper proposes a model for detecting likely damage to power transmission line elements by creating a detailed database on the region's power transmission line and combining this database with a real-time archive of lightning discharges. The model in accordance with the proposed algorithm will make it possible to compile a list of supports likely to be affected by a lightning discharge, to identify the affiliation of these supports to specific power lines, and to notify the maintenance personnel of these power lines about the coordinates and supports of the power lines, where damage is possible. The model has a low cost and operating cost, can be easily deployed in any power system, but requires sufficient accuracy to detect lightning discharges and determine their coordinates. The solution to the problem of detection accuracy comes down to installing in the region a certain number of lightning direction finders of a particular system. The paper considers these issues on the example of the power system of the Murmansk region and lightning direction finders of the Blitzortung system.

(in Russian, стр.6, fig. 5, tables. 0, ref 12, AdobePDF, AdobePDF 0 Kb)