Search

Results:

Vol. 25 (2022 year), No. 4, DOI: 10.21443/1560-9278-2022-25-4

Vinogradov A. V., Lansberg A. A., Vinogradova A. V.
Analysis of the technical condition and service life of 35–110 kV overhead power transmission lines in the Oryol Region

The assessment of the technical and operational characteristics of overhead transmission lines of voltage classes 35–110 kV in the Oryol Region has been carried out in accordance with the methodology presented in the order of the Ministry of Energy of the Russian Federation dated July 26, 2017 No. 676; their service life was determined according to STO 56947007-29.240.01.053-2010. The analysis of the length of overhead lines and the types of conductors used has taken place using support-by-support schemes. In the construction of 35 kV lines, steel-aluminum wire (sectional area – 70 mm2) is mainly used, the length of which is 1,358,456 km, and 110 kV overhead lines are made using an AS-120 conductor (1,094 km). Overhead transmission lines are characterized by high indicators of technical condition, since 40 % of lines of voltage class 35 kV and 53 % of lines of voltage class 110 kV are in very good technical condition with a wear rate of no more than 15 %. The study has found that 71 % of overhead lines with a voltage of 35 kV and 85 % of lines with a voltage of 110 kV have been in operation for more than 35 years; at the same time, due to the implementation of a timely strategy for maintenance and repair, the lines are characterized by high indicators of technical condition.

(in Russian, стр.9, fig. 6, tables. 0, ref 19, AdobePDF, AdobePDF 0 Kb)

Vol. 28 (2025 year), No. 4, DOI: 10.21443/1560-9278-2025-28-4/1

Vinogradova A. V., Vinogradov A. V., Sorokin N. S.
Evaluation of the efficiency of replacing one power transformer with two in 10/0.4 kV single transformer substations under seasonal load

The efficiency of replacing one power transformer with two in 10/0.4 kV single transformer substations under seasonal load has been evaluated using the example of replacing a 100 kVA transformer. The installation of two transformers with capacities of 40 and 40 kVA; 40 and 63 kVA; 63 and 63 kVA has been considered. The effects of reducing electricity losses have been evaluated depending on the load factors of transformers and on increasing the reliability of power supply to consumers. The variants of circuits of a single-transformer non-automated, automated substation and an automated substation with two transformers have been compared. A methodology for evaluating the effectiveness of options has been developed. The most rational option in the considered example is to replace it with two 63 and 63 kVA transformers. It achieves the effect of reducing electricity losses with an average annual load factor of 100 kVA equal to or less than 0.35, as well as with a load factor of 100 kVA equal to or greater than 0.55. The effect of increased reliability is to reduce the time of interruptions in the power supply to consumers from 9.44 hours/year to 0.79–1.33 hours/year, depending on the amount of electricity consumed from the transformer substations.

(in Russian, стр.13, fig. 4, tables. 5, ref 19, AdobePDF, AdobePDF 0 Kb)