Some Features of Calculating the Lightning-Induced Damages to Overhead Power Line Elements

The article presents the main principles and specific features of a procedure for calculating the lightning-induced damage inflicted to power transmission line elements based on a probabilistic approach. The procedure takes into account the modern concepts on how lightning strikes at ground objects. A model simulating the development of a downward lightning leader in a manner maximally close to the real negative stepped leader development process is proposed. A scheme illustrating how a leader is targeting at a ground object has been developed. By solving the problem within the framework of 3D modeling, the possibility of a connecting leader to develop not only from the phase wires and overhead ground wires, but also from the line supports can be analyzed. Based on experimental and theoretical studies, a probabilistic approach for conditions under which the streamer corona flash transforms into an upward leader is proposed. The possibility of taking into account the natural and climatic conditions, and topography in the line route regions is considered. The elaborated procedure and the software package developed on its basis allow the places of lightning strikes at overhead power line elements and their probabilities to be predicted in the most grounded manner, which will make it possible to set up reliable overhead power line protection.

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One Type Damper Used for Preventing Galloping of the Electric Power Line

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.374-377.2057 ◽

2011 ◽

Vol 374-377 ◽

pp. 2057-2060

Author(s):

Li Min Sun ◽

Jing Chao Zou

Keyword(s):

Transmission Line ◽

Electric Power ◽

High Speed ◽

Power Transmission ◽

Power Line ◽

Power Transmission Line ◽

Patent License ◽

Electric Power Line ◽

New Type ◽

Overhead Power Line

When the power transmission line is covered with ice and snow in the winter, the galloping of power line often happens. A new type of damper used for preventing galloping of the electric power transmission line has been put forward and received patent license of China. The damper like fan blades, which can rotate about the axes of the power line at 360°, is fixed on the overhead power line. It hangs on the line when there is no wind. The blade rotates at high speed in the plane vertical to wind when there is wind, which results in a gyroscope. The theorem of angular momentum of a gyroscope is used in the design of the damper. Model tests of this kind of damper have been carried out and the results show that it is successful in preventing galloping of the cable model.

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Methodology of overhead power transmission line pylons technical state assessment with typical exploitation faults accounted

Engineering Journal Science and Innovation ◽

10.18698/2308-6033-2021-2-2053 ◽

2021 ◽

Author(s):

T.V. Burnysheva ◽

A.N. Kozhevnikov

Keyword(s):

Natural Frequencies ◽

Power Transmission ◽

Power Line ◽

State Assessment ◽

Modal Testing ◽

Additional Advantage ◽

Structure Defects ◽

Safety Estimation ◽

Overhead Power Transmission Line ◽

Overhead Power Line

Structure safety estimation via the results of modal testing is widely used in building field. However, overhead power line pylons are so specialised that it is not possible to expand existing standards so that those could be employed to assess pylon conditions. These standards do not contain any information about the pylon eigenvalues, methodology of full-scaled experiment execution or criteria to differentiate pylons with respect to the extent of the structure defects occurred. This means that it is necessary to develop a dedicated approach to estimating the safety of this type of structures. The method proposed boasts an additional advantage, that is, it takes into account the operating defects that are typical for the type of structures under consideration. The point of this method is comparing the computed and experimentally determined natural frequencies of overhead power line pylons. This comparison enables us not only to detect the defect type present in the structure, but also to find whether it is located closer to the base of the structure or in the latticework on one of the sides. The paper presents the results of using our method for estimating the safety of intermediate towers for a 110 kV overhead power line as represented by the SV-5 segment and states the advantages of using our method when planning real-time inspection of structures, as well as for monitoring select towers constantly.

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The Influence of Overhead Power Line Effective Voltage Deviations from the Nominal Value on Relative Power Losses and on Specific Discounted Costs for Power Transmission

Vestnik MEI ◽

10.24160/1993-6982-2020-1-39-48 ◽

2020 ◽

Vol 1 (1) ◽

pp. 39-48

Author(s):

Aleksey A. Gerkusov ◽

Keyword(s):

Power Transmission ◽

Power Line ◽

Relative Power ◽

Power Losses ◽

Effective Voltage ◽

Discounted Costs ◽

Overhead Power Line

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Variabilidade Espacial e Temporal de Descargas Atmosféricas na Região Norte

Revista Brasileira de Geografia Física ◽

10.26848/rbgf.v13.5.p2074-2085 ◽

2020 ◽

Vol 13 (5) ◽

pp. 2074

Author(s):

Arthur Da Costa Almeida ◽

Jose Ricardo Santos de Souza ◽

Marcela Machado Pompeu ◽

Wanda Maria Do Nascimento Ribeiro

Keyword(s):

Statistical Analysis ◽

Transmission Lines ◽

Temporal Variability ◽

Power Transmission ◽

Relevant Information ◽

Northern Region ◽

Climatic Conditions ◽

Spatial And Temporal Variability ◽

Detailed Knowledge ◽

Lightning Strikes

A região norte do Brasil, que inclui uma parte da Amazônia, possui condições climáticas que favorecem a ocorrência de chuvas ao longo de todo o ano, muitas delas com grande quantidade de descargas atmosféricas. Um conhecimento detalhado da variabilidade espacial e temporal desses eventos pode ajudar tanto no planejamento de sistemas de proteção de linhas de transmissão de energia elétrica, sistemas de telecomunicações, como no apoio às populações que habitam nessa região. Neste trabalho foi feita uma análise estatística de dados da rede de detecção de raios Starnet, num total de mais de 220 milhões de eventos que ocorreram na área de estudo durante os anos de 2009 a 2015, extraindo-se deles informações relevantes quanto às ocorrências de descargas atmosféricas na região. Como resultado das análises estatísticas, foram produzidos mapas com a densidade de raios, mapa de dias de tempestade e gráficos mostrando a sua distribuição horária, mensal e por dia e hora ao longo do ano. Spatial and Temporal Variability of Lightning in the Northern Region A B S T R A C TThe Northern region of Brazil, which includes part of the Amazon, has climatic conditions that favour the occurrence of rainfall throughout the year, many of them with a large number of lightning strikes. Detailed knowledge of the spatial and temporal variability of these events can help both in the planning of protection systems for electric power transmission lines, telecommunications systems as in supporting the populations that live in that region. In this research, a statistical analysis of the Starnet lightning location system data was produced, in a total of more than 220 million events that occurred in the study area during the years of 2009 to 2015, extracting from them relevant information regarding the occurrences of lightning strikes in the region. As a result of this statistical analysis, maps were produced with the lightning density and thunderstorm days over the region, with graphs showing their monthly, daily and hourly distribution throughout the year.Keywords: northern region, lightning density, keraunic map

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