Journal articles: 'Overhead line network'

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Lazaropoulos, Athanasios G. "Wireless Sensor Network Design for Transmission Line Monitoring, Metering, and Controlling: Introducing Broadband over Power Lines-Enhanced Network Model (BPLeNM)." ISRN Power Engineering 2014 (June 4, 2014): 1–22. http://dx.doi.org/10.1155/2014/894628.

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This paper introduces the broadband over power lines-enhanced network model (BPLeNM) that is suitable for efficiently delivering the generated data of wireless sensor networks (WSNs) of overhead high-voltage (HV) power grids to the substations. BPLeNM exploits the high data rates of the already installed BPL networks across overhead HV grids. BPLeNM is compared against other two well-verified network models from the relevant literature: the linear network model (LNM) and the optimal arrangement network model (OANM). The contribution of this paper is threefold. First, the general mathematical framework that is necessary for describing WSNs of overhead HV grids is first presented. In detail, the general mathematical formulation of BPLeNM is proposed while the existing formulations of LNM and OANM are extended so as to deal with the general case of overhead HV grids. Based on these general mathematical formulations, the general expression of maximum delay time of the WSN data is determined for the three network models. Second, the three network models are studied and assessed for a plethora of case scenarios. Through these case scenarios, the impact of different lengths of overhead HV grids, different network arrangements, new communications technologies, variation of WSN density across overhead HV grids, and changes of generated WSN data rate on the maximum delay time is thoroughly examined. Third, to assess the performance and the feasibility of the previous network models, the feasibility probability (FP) is proposed. FP is a macroscopic metric that estimates how much practical and economically feasible is the selection of one of the previous three network models. The main conclusion of this paper is that BPLeNM defines a powerful, convenient, and schedulable network model for today’s and future’s overhead HV grids in the smart grid (SG) landscape.

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Yang, Zhiwang, Nikola Zivlak, Ming Xu, and Marko Ljubicic. "Study on overhead transmission line on-line monitoring technology." Thermal Science 20, suppl. 2 (2016): 383–91. http://dx.doi.org/10.2298/tsci151214024y.

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paper introduces a new idea for overhead transmission line online monitoring. The basis of the paper has been developed upon years of research conducted by power engineers, and a new advanced transmission line safe operation monitoring system is proposed successfully. Furthermore, we used artificial neural network(ANN) for diagnosis examples, to prove the feasibility and effectiveness of the advanced transmission line safe operation system.

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Dong, Ai Hua, Xin Lin Geng, Yi Yang, Ying Su, and Meng Yao Li. "Overhead Power Line Fault Positioning System." Applied Mechanics and Materials 329 (June 2013): 299–303. http://dx.doi.org/10.4028/www.scientific.net/amm.329.299.

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Aimed at the situations of the low accuracy of overhead line fault detection and the high cost of line fault information transmission with the aid of GSM correspondence network, this paper introduces overhead line fault detection and location system as the core of industrial computer. The combination of software and hardware, the methods of current rate of change and zero current detection are used, and so the accuracy of short circuit fault detection is improved. The features of ground phase voltage drop and the 5th harmonic current are integrated, and the accuracy of ground fault detection circuit is improved. Zigbee wireless communication technology is used to make into independent signal transmission system, which not only reduces the system's operating costs but also ensures the reliable transmission of signals. Taking Kingview 6.51 software as development platform, the monitoring program and display with many functions are designed. The system has been put into operation, running in good condition, and passed concluding and acceptance smoothly.

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wei, Song, Wang Yanfeng, and Wang shuanghu. "The Study on Lightning Disaster Risk Assessment Model of 10kV Overhead Line." MATEC Web of Conferences 173 (2018): 01008. http://dx.doi.org/10.1051/matecconf/201817301008.

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Taking all kinds of affecting factors into account, the 10kV overhead line of distribution network lighting disaster risk is studied. Historical hidden fault, line equipment, topography, climatic conditions and social impact are selected as key factors of damage and the impact. The correlation among the factors and the weight ratio of each factor were studied. The risk assessment model of 10kV distribution network overhead line was established by multi-factor, hierarchical classification assessment method. It solves the evaluation index insufficient problem of the single factor as the evaluation condition, and provides the theoretical research and practical support to the 10kV overhead line reconstruction and the lightning prevention. The reliability and effectiveness of the research results have been proved by practical application in distribution network operation and maintenance control.

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Fan, Fei, Gongping WU, Man Wang, Qi Cao, and Song Yang. "Robot Delay-Tolerant Sensor Network for Overhead Transmission Line Monitoring." Applied Sciences 8, no. 6 (May 23, 2018): 847. http://dx.doi.org/10.3390/app8060847.

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Vintan, Maria, and Adrian Buta. "Ground fault distribution on overhead transmission lines." Facta universitatis - series: Electronics and Energetics 19, no. 1 (2006): 71–84. http://dx.doi.org/10.2298/fuee0601071v.

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When a ground fault occurs on an overhead transmission line in a power network with grounded neutral, the fault current returns to the grounded neutral through the tower structures, ground return paths and ground wires. This paper presents an analytical method in order to evaluate the ground fault current distribution in an effectively grounded power network. The effect of soil resistivity, ground resistance of towers and power line configuration, on the magnitude of return currents, has been examined.

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Jin, Xu, Fudong Cai, Mengxia Wang, Yang Sun, and Shengyuan Zhou. "Probabilistic prediction for the ampacity of overhead lines using Quantile Regression Neural Network." E3S Web of Conferences 185 (2020): 02022. http://dx.doi.org/10.1051/e3sconf/202018502022.

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The ampacity of overhead transmission lines play a key role in power system planning and control. Due to the volatility of the meteorological elements, the ampacity of an overhead line is timevarying. In order to fully utilize the transfer capability of overhead transmission lines, it is necessary to provide system operators with accurate probabilistic prediction results of the ampacity. In this paper, a method based on the Quantile Regression Neural Network (QRNN) is proposed to improve the performance of the probabilistic prediction of the ampacity. The QRNN-based method uses a nonlinear model to comprehensively model the impacts of historical meteorological data and historical ampacity data on the ampacity at predictive time period. Numerical simulations based on the actual meteorological data around an overhead line verify the effectiveness of the proposed method.

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Jie, Xia, and Rui Jun Jing. "On-Line Decrypting: A Homomorphic Realization for Network Coding." Applied Mechanics and Materials 543-547 (March 2014): 2728–32. http://dx.doi.org/10.4028/www.scientific.net/amm.543-547.2728.

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The paper studies the problem of communicating message secretly in the network performing random linear network coding, where the network internal nodes are allowed to randomly mix the incoming packets and then forward. The paper proposes HoNet, an end-to-end homomorphic encryption that is theoretically proved secure against network adversaries who can fully access the information of network coding schemes and eavesdrop every network transmission. A direct payoff of homomorphic encryption is that network nodes could on-line decrypt (or re-encrypt) the mixed ciphertexts, which significantly increases network throughput in scenarios such as peer-to-peer networks and satellite systems. In particular, HoNet addresses the two main challenges faced by the traditional homomorphic encryption schemes for point-to-point transmissions:high computational overhead and throughput loss-rate. To be precise, HoNet possesses linear time nodes complexity and asymptotically zero loss-rate.

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He, Yongping, Xiaomin Liu, Kai Yang, Shangke Liu, and Yaxuan Chen. "Research on Overhead Line Cost Prediction Based on Index Construction." E3S Web of Conferences 136 (2019): 01014. http://dx.doi.org/10.1051/e3sconf/201913601014.

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In order to meet the growing demand of the society for electric power, the construction of electric power infrastructure is constantly carried out. However, investment in construction and cost control are particularly important. Because of its own characteristics, overhead line project cost control management is difficult to carry out. According to the characteristics of overhead line engineering, this paper constructs an overhead line engineering cost index system composed of 24 indexes including voltage grade from three aspects: technical conditions, engineering quantity attribute and cost attribute. Combining with the actual data of the completed project, the BP neural network algorithm is used to predict the static investment of the project. The accuracy of the prediction model reaches 99.9%. This verifies the rationality and comprehensiveness of the overhead line project cost index system constructed in this paper, and provides reliable guidance for the overhead line project cost management.

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Szultka, Agata, Seweryn Szultka, Stanislaw Czapp, and Ryszard Zajczyk. "Voltage Variations and Their Reduction in a Rural Low-Voltage Network with PV Sources of Energy." Electronics 10, no. 14 (July 7, 2021): 1620. http://dx.doi.org/10.3390/electronics10141620.

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Renewable sources of energy (RES), especially photovoltaic (PV) micro-sources, are very popular in many countries. This way of clean power production is applied on a wide scale in Poland as well. The Polish legal regulations and tariffs specify that every prosumer in a low-voltage network may feed this network with a power not higher than the maximum declared consumed power. In power networks with RES, the voltage level changes significantly along the power line and depends on the actually generated as well as consumed power by particular prosumers. There are cases that prosumers connected to this line cannot produce and inject the full permissible power from PV sources due to the level of a voltage higher than the technically acceptable value. In consequence, it leads to the lack of profitability of investments in installations with PV sources. In this paper, voltage variations in a real rural low-voltage network with PV micro-sources are described. The possible two general solutions of voltage levels improvement are discussed—increase in the cross-sectional area of the bare conductors in the existing overhead line as well as the replacement of the overhead line with a cable line. The recommended solution for the analyzed network, giving the best reduction of voltage variations and acceptable cost, is underlined. Such a recommendation can also be utilized in other rural networks.

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Sun, Guo Kai, Jing Xiao Yu, and Meng Yao Yuan. "For Transmission Line Fault Type Recognition Based on RBF Neural Network." Applied Mechanics and Materials 687-691 (November 2014): 895–99. http://dx.doi.org/10.4028/www.scientific.net/amm.687-691.895.

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The study of existing deficiencies, on the basis of overhead transmission line fault detection based on radial basis function (RBF) neural network theory, the fundamental frequency power spectrum as characteristic vector of fault signal, this paper proposes a new method of transmission line fault type identification. The system with complex structure of 10 KV overhead transmission lines as the research object, on the basis of the transmission line model is established by using Simulink software, for different types of short circuit fault simulation sampling, extract fault features, combined with the zero sequence current, as the input vector, establish the RBF neural network for fault type. Results show that: the fundamental frequency in fault signal power spectrum as the feature vector is easy to extract, information is more concise, the RBF neural network in the feasibility in training high, identify accurately and quickly.

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Haladin, Ivo, Stjepan Lakušić, and Ivan Duvnjak. "Evaluation of tramway overhead line system in city of Osijek." MATEC Web of Conferences 180 (2018): 06003. http://dx.doi.org/10.1051/matecconf/201818006003.

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Overhead line system is a vital element of any electrified railway infrastructure. Its performance reflects to all vital parameters such as traction, reliability, availability and safety of railway infrastructure. Operator GPP Osijek runs a 27.5 km long tramway network which plays a key role in transit system of the city of Osijek, Croatia. In 2016 GPP Osijek applied to a tender for acquisition of new rolling stock with 85% EU investment. Mayor requirement prior to rolling stock acquisition was to document, analyse and upgrade current infrastructure (including track structure, electric substations and catenary) to an optimal level. Task of measurement and evaluation of tram track structure and catenary has been appointed to University of Zagreb Faculty of Civil Engineering. Overhead line analysis comprised from several measuring procedures, including supporting columns evaluation, catenary stagger, height, shocks and wear. Such extensive analysis included GPS positioning and on-site evaluation of 1214 supporting columns of overhead line, as well as overhead line measurements using an instrumented tram vehicle on 18 km of track. For conducting overhead catenary wire measurements, a tram pantograph has been fitted with equipment for measuring catenary height, accelerometers for shock measurement, camera, ruler and GPS for stagger measurement. Catenary wire wear was checked manually from catenary inspection vehicle. To conduct measurements, power had to be switched off on all electric substation along the route and tram vehicle had to be towed by a catenary inspection vehicle. All the data has been analysed and presented to end user in a user-friendly and intuitive GIS environment capable of further updates and detailed analyses. Evaluation of overhead line based on direct measurement results pointed out all the defects and weak spots on the system. It resulted in a series of recommendations for reconstruction and upgrade of the catenary system to fit the need of existing state and further development of tramway network.

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Jeyanthi, C., H. Habeebullah Sait, K. Chandrasekaran, and C. Christopher Columbus. "A Communication Model Framework for Electric Transmission Line Monitoring Using Artificial Bee Colony Algorithm." Journal of Circuits, Systems and Computers 29, no. 04 (July 9, 2019): 2050063. http://dx.doi.org/10.1142/s0218126620500632.

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The natural calamity and physical malfunction in the overhead transmission line cause bad impact on the networks such as mechanical failures, power losses, reduction of line capacity, and voltage drop. These adverse impacts can be reduced by implementing proper monitoring systems. Wireless sensor network is an apt mechanism to monitor the overhead transmission network because of its physical configuration. This paper portrays the communication between wireless sensor networks and central data processing station. Cellular communication can directly transmit information through an assisted cellular module (CM) based on the probability of cellular coverage. In this paper, one of the modern optimization techniques, i.e., artificial bee colony algorithm, is used to study the problem of CM placement of cellular communication. By using this algorithm, the optimal number and location of the CMs for a test system varied from 10 to 100 are determined. A novel optimal link path scheme is proposed to check the condition of the required quality of services of both cellular/ZigBee users. The attained results show that the methodology is best suited to acquire low cost solution for the cellular module placement problem.

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14

Yabo, Shen, Ma Ning, Men Yan, Zhao Xin, and Jia Zhenghao. "Research on overhead line Engineering Cost prediction based on PCA-LSSVM model." E3S Web of Conferences 185 (2020): 02023. http://dx.doi.org/10.1051/e3sconf/202018502023.

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In recent years, the investment projects of overhead line engineering increase year by year. Establishing scientific cost prediction concept and optimizing cost prediction method can improve the investment utilization efficiency. Based on the actual cost data of 110kV overhead line project, this paper extracts the principal component factor through principal component analysis and eliminates the correlation between the original indicators. Then, the training sample is input into the least-squares support vector machine model to build a learning network. Finally, the predicted value of the model is compared with the actual cost level for analysis. The prediction results show that the average error rate is less than 5%, indicating that the PA-LSSVM model constructed in this paper can effectively predict the overhead line engineering cost.

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Noh, Shin-Eui, Yi-Gwhan Kim, Sung-Hun Lim, and Il-Dong Kim. "Dynamic Line Rating Prediction in Overhead Transmission Lines Using Artificial Neural Network." Journal of the Korean Institute of Illuminating and Electrical Installation Engineers 28, no. 1 (January 31, 2014): 79–87. http://dx.doi.org/10.5207/jieie.2014.28.1.079.

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Kilsby, Paul, Rasa Remenyte-Prescott, and John Andrews. "A Petri Net-based life cycle cost analysis approach." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 233, no. 1 (June 3, 2018): 90–102. http://dx.doi.org/10.1177/0954409718780106.

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Railway infrastructure providers, such as Network Rail, who owns and manages the British railway infrastructure, can improve the performance and reduce the life cycle cost of their assets through delivering effective asset management. Having the capability to use computer-based models to predict the future performance and life cycle cost of an asset group is a key enabling mechanism for implementing effective asset management. Decision makers can determine the optimum maintenance strategy and the best allocation of capital expenditure based on evidence from modelling results. This paper shows how probabilistic modelling can be used to evaluate asset management projects of the railway overhead line equipment system and undertake a life cycle cost analysis through the use of a stochastically timed high-level Petri Net. A complete modelling framework has been developed, where the components and their maintenance strategies are selected as inputs, and the Petri Net model is used to calculate outputs associated with the performance and life cycle cost of the overhead line equipment system for the corresponding components and strategies considered. This paper presents the practical use of the developed model and describes how the outputs can be used by asset managers to understand the expected system performance and cost over its life cycle. The range of outputs described are the most detailed for such models studying the overhead line equipment and other engineering systems in literature. Whilst the railway overhead line equipment system is used as an example study, the modelling framework is transferable to asset management projects for other engineering systems.

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Buyakova, Natalia V., Andrey V. Kryukov, Dmitriy A. Seredkin, and Le Van Thao. "Simulation of Electromagnetic Fields Occurring at Intersection of Traction Networks and Multicircuit Power Lines." E3S Web of Conferences 209 (2020): 07002. http://dx.doi.org/10.1051/e3sconf/202020907002.

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Traction networks (TN) 25 kV generate higher electromagnetic fields (EMF) with frequency 50 Hz, whose strengths at a standardized height of 1.8 m, as a rule, do not exceed the permissible norms for electrical personnel. In places where railroads routes intersect with high voltage overhead power supply lines (OPL), interference of fields, generated by the traction network and OPL, occurs. This can lead to an increase in strengths and a complication of the EMF spatial structures. The article presents simulation results performed for a complex intersection, while 25 or 2 х 25 kV TN is crossed by a three-circuit 110-220 kV overhead power line at 90 degrees angle. Fazonord software application was used for simulating EMF strengths in points of traction networks and OPL intersection. Based on modeling results the following conclusions have been made: at intersection points of 1х25 kV traction network with a three-chain 110 - 220 kV power transmission line, the electrical field strength does not exceed the value acceptable for electrical personnel and reaches 4.2 kV/m; at the intersection with 2 х 25 kV traction network, this parameter decreases to 2.7 kV/m; the maximum amplitude of the magnetic field at the intersection points increases slightly.

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Rantala, Ville, Teijo Lehtonen, Pasi Liljeberg, and Juha Plosila. "Analysis of Monitoring Structures for Network-on-Chip." International Journal of Embedded and Real-Time Communication Systems 2, no. 1 (January 2011): 49–67. http://dx.doi.org/10.4018/jertcs.2011010103.

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Monitoring services are essential for advanced, reliable NoC systems. They should support traffic management, system reconfiguration and fault detection to enable optimal performance and reliability of the system. The paper presents a thorough description of NoC monitoring structures and studies earlier works. A distributed monitoring structure is proposed and compared against the structures presented in previous works. The proposed distributed network monitoring system does not require centralized control, is fully scalable and does not cause significant traffic overhead to the network. The distributed structure is in line with the scalability and flexibility of the NoC paradigm. The paper studies the monitoring structure features and analyzes traffic overhead, monitoring data diffusion, cost and performance. The advantages of distributed monitoring are found evident and the limitations of the structure are discussed.

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Liao, Huanyue, and Wei Liu. "Weather-based dynamic line rating of overhead transmission lines over Europe interconnected network." IOP Conference Series: Materials Science and Engineering 382 (July 2018): 052035. http://dx.doi.org/10.1088/1757-899x/382/5/052035.

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Wang, Hong Liang, Min Cao, Da Da Wang, Peng Li, and Shao Quan Zhang. "The Research and Design of Overhead Transmission Line Temperature Monitoring Technology Based on ZigBee." Advanced Materials Research 846-847 (November 2013): 578–82. http://dx.doi.org/10.4028/www.scientific.net/amr.846-847.578.

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Overhead transmission line temperature monitoring system for the protection of the safe operation of the transmission line is important, this paper introduces the ZigBee protocol level and the network topology, using the existing hardware platform designed and implemented programming ZigBee protocol stack, and then studied and designed based on ZigBee technologies overhead Transmission Lines temperature wireless data collection, gives the overall system architecture and hardware circuits, software systems, and do the experiment. After the unified information platform and experiment, the method is proved to be effective and feasible. The technology has high reliability, scalability, and low operating costs, especially for remote areas of Yunnan, China's high-voltage transmission line temperature monitoring.

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Xu, Ke Ju, Lei Yang, Da Da Wang, Chao Zhou, Shao Quan Zhang, Qing Jun Peng, and Xiao Ming Rui. "Parametrical Finite Element Modeling of Overhead Transmission Line-Towers System." Applied Mechanics and Materials 313-314 (March 2013): 809–12. http://dx.doi.org/10.4028/www.scientific.net/amm.313-314.809.

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With large-scale development of ultra high-transmission network, the structure of transmission line-towers system tends to the tower higher, the cross-section of transmission lines larger and span between towers longer. As the increasing of transmission lines voltage grade, transmission line-towers system has higher requirements on static and dynamic stability. It is difficult for traditional design method to meet the demands of new transmission line-towers, not to mention shorten the design cycle, improve design quality. In this paper, we establish overhead transmission line-towers system model based on parameterized finite element method, by gradually increasing the thickness of the icing, iced load, wind load, weight, mechanical properties under the action of the load and the conductor tension. The analysis results show that the model can effectively reflect the mechanical properties of the transmission towers, and improve the quality of the design, greatly shortening the design cycle.

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Pylarinos, D. "Overhead Transmission Line Maintenance in Crete and Rhodes: 2016-2020." Engineering, Technology & Applied Science Research 11, no. 1 (February 6, 2021): 6833–44. http://dx.doi.org/10.48084/etasr.4036.

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The Greek islands of Crete and Rhodes are equipped with isolated transmission systems that fall under the jurisdiction of the Islands Network Operation Department of HEDNO S. A., which carries out their operation and maintenance on behalf of PPC S.A. After 2016, the Transmission Line Operation and Maintenance Subsection of the Department, started to incorporate new approaches to improve the routine work of the subsection. These approaches include Unmanned Aerial Vehicle (drone) inspections, GIS/GPS software/applications and project management/issue tracking tools such as Mantis Bug Tracker (or MantisBT. This paper provides a brief review of the maintenance practices in combination with the properties and peculiarities of the specific systems, and further investigates the MantisBT records from 2016 to 2020, in order to provide a view of the routine work of transmission line maintenance through the case studies of Crete and Rhodes. It should be noted that the majority of these issues are related to the Cretan transmission system and thus, this paper also aims to provide a screenshot of the situation before the interconnection of the isolated Cretan Transmission System to the mainland system, expected to initiate in 2021.

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S., SKRYPNYK. "Substantiation of the choice of the replacement scheme of line for mathematical modeling of 20 kV power supplies." Journal of Electrical and power engineering 24, no. 1 (May 21, 2021): 69–72. http://dx.doi.org/10.31474/2074-2630-2021-1-69-72.

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In the current global economic crisis and acute shortage of energy resources, increasing importance is attached to energy saving measures, economical and careful consumption of raw materials, materials, electricity and heat, environmental safety of industrial production. During the reconstruction of existing power supply systems of industrial enterprises, modern progressive solutions should be considered and implemented, morally and physically obsolete electrical equipment should be replaced, namely the introduction of new electrical equipment for transition from 6/10 kV to 20 kV in Ukrainian power systems. It is also necessary to pay attention to the improvement of power supply circuits and distribution networks, the implementation of complex automation of complex technological processes, rational compensation of reactive power at all levels of power supply systems. In the power system, the main transport link is the power line. Power lines (transmission lines) are long conductors suspended at a safe distance from the ground overhead lines (overhead lines) or cable lines (overhead lines) in which conductors are insulated from each other and from the environment and protected by insulation and armor electricity. Power lines are the most massive elements of the power supply system, they connect the individual nodes of its circuit. Longitudinal and transverse parameters are distinguished in alternative schemes. The load current flows through the longitudinal parameters, voltage is applied to the transverse ones. The replacement circuit of the electrical network consists of replacement circuits of the following elements: power lines, transformers, reactors, capacitors, loads, power sources. Calculating the steady-state modes of power systems, the substitution schemes of the elements are given in a single-line design, because the parameters of all phases are symmetrical. In local and local electrical networks with a relatively short length and low rated voltage, the conduction currents are small compared to load currents. Therefore, in typical electrical calculations of these networks, the capacitive conductivity of the lines is not taken into account. However, for these networks, the accounting of capacitive conductivities is necessary when considering some modes, the existence of which in itself is due only to the presence of capacitive conductivities. For example, the mode of single-phase ground fault in a network with isolated or compensated neutral or analysis of the modes of operation of neutrals of electrical networks of different voltage classes cannot be performed without taking into account the capacitive conductivity of these networks. When switching the power system of Ukraine to the nominal voltage of 20 kV, it should be taken into account that the transmission line will be replaced in the sections of both the overhead power line and cable power line, namely 35, 10, 6 kV. The replacement scheme must describe all the characteristics and properties of the elements of cable and overhead lines in accordance with real conditions. Thus, it is not expedient to use simplified substitution circuits that neglect energy parameters and properties of conductors to study the parameters of transmission lines. The use of a complete "P" -shaped scheme for the analysis of the parameters of transmission lines and transmission lines for a voltage of 20 kV is the basis of mathematical modeling of the transmission system in the distribution networks of our country.

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Kim, Sung-Duck. "A Reassessment for Dynamic Line Rating of Aged Overhead Transmission Lines in Kepco's Network." Journal of the Korean Institute of Illuminating and Electrical Installation Engineers 24, no. 10 (October 31, 2010): 123–29. http://dx.doi.org/10.5207/jieie.2010.24.10.123.

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Chaoyue, Gu, Li Zhe, Shi Jintao, Sheng Gehao, and Jiang Xiuchen. "Pin Defect Detection Method of UAV Patrol Overhead Line Based on Cascaded Convolution Network." Journal of Physics: Conference Series 1659 (October 2020): 012021. http://dx.doi.org/10.1088/1742-6596/1659/1/012021.

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Abdurakhmanov, Abdula, Sergey Glushkin, Vladislav Plotnikov, and Andrey Shuntov. "Again about reliability characteristics of electrical power grids elements." E3S Web of Conferences 58 (2018): 01002. http://dx.doi.org/10.1051/e3sconf/20185801002.

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The reliability characteristics of the (auto)transformers and overhead transmission lines of the unified national electric grid are subjected to statistical analysis. It is shown that their scheduled outages for scheduled or unscheduled repairs, as well as maintenance, weaken the network layout much more than emergency repairs. At the same time, there was a noticeable deterioration in the (auto)transformers and overhead transmission line reliability indexes over the last 30 years, which requires the development and adoption of appropriate organizational and technical solutions.

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Liu, Weike, Mengbao Zhou, Jiarui Hu, Songqi Wu, Xianhui Cao, Jie Xiong, Lian Hu, et al. "Analysis on three typical abnormal microstructures of overhead power line suspension clamps." E3S Web of Conferences 165 (2020): 06029. http://dx.doi.org/10.1051/e3sconf/202016506029.

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This article lists three typical abnormal microstructures of overhead power line suspension clamps, including inclusion, flake graphite and cementite network. A series of tests including macro check, hardness measurement, composition tests, Energy-dispersive x-ray analysis and metallographic observation have been carried out. The experimental results showed that the causes of abnormal microstructures mainly include: high content of impurities, flake graphite blank and unfulfilled annealing heat treatment. It is suggested to strengthen the supervision on suspension clamps before using, and focus on the quality inspection of metallographic structure and composition.

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Khavari, Saeid, Rahman Dashti, Hamid Reza Shaker, and Athila Santos. "High Impedance Fault Detection and Location in Combined Overhead Line and Underground Cable Distribution Networks Equipped with Data Loggers." Energies 13, no. 9 (May 7, 2020): 2331. http://dx.doi.org/10.3390/en13092331.

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Power distribution networks are vulnerable to different faults, which compromise the grid performance and need to be managed effectively. Automatic and accurate fault detection and location are key components of effective fault management. This paper proposes a new framework for fault detection and location for smart distribution networks that are equipped with data loggers. The framework supports networks with mixed overhead lines and underground cables. The proposed framework consists of area detection, faulty section identification, and high impedance fault location. Firstly, the faulty zone and section are detected based on the operation of over-current relays and digital fault recorders. Then, by comparing the recorded traveling times at both ends of lines, which are related to the protection zone, the faulty line is identified. In the last step, the location of the fault is estimated based on discrete wavelet transform. The proposed method is tested on a 20 kV 13 node network, which is composed of overhead lines and underground cables. The method is tested in both balanced and unbalanced configurations. The obtained results confirm the advantages of the proposed method compared with the current state-of-the art.

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M, Monica, Sivakumar P, Sivani S, Sandhiya D, Shameem Fathima J, and Hithesh Kumar S. "Overhead Line Fault Detection and Control using Internet of Things (IoT)." Bulletin of Scientific Research 2, no. 1 (April 22, 2020): 17–21. http://dx.doi.org/10.34256/bsr2013.

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In the modern era transmission line is the most important part of the power system. Its allegiance and requirement of power is grown up exponentially. The major role of transmission lines is to transmit electric power from the source area to distribution network. Transmission line protection is an important issue in power system because 85-87% of power system faults are occurring in transmission line. Energy leakage is one of the major problems that corporates faces in recent times. Only way to solve this problem is to come up with a mechanism that can detect the fault in transmission line automatically and intimate the authorities with a specific location. In this work the device uses the sensor to sense the voltage flow in the transmission line and detect if there is a variation in the voltage flow. If fault is detected, it can be automatically controlled by using relay and the system is also integrated with IoT mechanism, to intimate the responsible person with location information.

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Popova, Yekaterina, Oleg Voitov, and Lyudmila Semenova. "An algorithm to calculate feasible operating conditions of electrical network, given overhead conductor temperature and sag constraints." E3S Web of Conferences 58 (2018): 02015. http://dx.doi.org/10.1051/e3sconf/20185802015.

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The paper presents an algorithm to calculate feasible steady-state conditions of an electrical network. A distinctive feature of the calculation is the consideration of constraints on the temperature of bare conductor and the clearance of a controlled span of overhead line. This consideration is based on forming and solving an equation of conductor heat balance to calculate the conductor temperature depending on the current flowing through the conductor and environmental factors, including the actual values of air pressure and air temperature. The paper presents the results of numerical calculations performed for individual overhead lines and for a test 16-node scheme of electrical network. The results illustrate the algorithm performance and the importance of considering the above constraints.

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Dai, Yun Hong, Shi Bin Liang, Ming Yao Hu, Ying Na Li, Zhen Gang Zhao, Tao Xie, Qing Sheng Tian, and Chuan Li. "The Method Analysis of Overhead Transmission Line Single-Phase Grounding Fault Detection and Location." Advanced Materials Research 1030-1032 (September 2014): 1360–65. http://dx.doi.org/10.4028/www.scientific.net/amr.1030-1032.1360.

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Small current grounding power system is widely used in overhead transmission line in medium voltage distribution network in China. Because of its long lines, branch, space truss structure is complex, low level of automation, It is easily influenced by outside force and the natural environment, and single-phase grounding failure rate is high. It is an important topic to quickly and accurately detect the location of the fault line, and improve the reliability of power supply and distribution system.This paper has carried on the induction and the comparison of various fault detection and location method of overhead transmission line which is currently used in single phase to ground, and analyzed their advantages and disadvantages,given the corresponding conclusions, provided the reference for finding out the reasonable single-phase earth fault location method or improvement.

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Berjozkina, S., A. Sauhats, A. Banga, and I. Jakusevics. "Evaluation of Thermal Rating Methods Based on the Transmission Line Model / Termisko Jaudas Metožu Novērtējums, Balstoties Uz Esošo Elektropārvades Līnijas Modeli." Latvian Journal of Physics and Technical Sciences 50, no. 4 (August 1, 2013): 22–33. http://dx.doi.org/10.2478/lpts.2013.50.4.22.

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Abstract Electric power consumption has been growing continuously, especially in the last years. Therefore, implementation of new advanced technologies such as the overhead line thermal monitoring is topical for improvement of the existing transmission line network in order to increase its throughput capacity and reliability of power supply. In general, the real-time thermal monitoring systems are designed based on the existing methods using the limiting conditions for ampacity determination of high-voltage overhead lines. The paper considers commonly used methods for thermal rating estimation which include computation of the conductor temperature and of the conductor sag. Comparative analysis was performed for the measured and calculated steady-state conductor temperatures and line sagging, based on which the thermal rating methods were tested. The experimental measurements were conducted for three cases using special monitoring equipment. The study has been carried out based on the existing line model of the Latvian transmission grid

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Tong, Bu Sheng, Yu Xiang Lv, Bei Ge Yang, Hui Xue, and Shan Zhi. "Design and Application of Aeolian Vibration Monitoring System for Overhead Transmission Line." Applied Mechanics and Materials 239-240 (December 2012): 456–61. http://dx.doi.org/10.4028/www.scientific.net/amm.239-240.456.

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Aim at the shortage of traditional Aeolian vibration fatigue tests and theoretical models for transmission line, the Aeolian vibration monitoring system of transmission line based on the ZigBee wireless network was designed. The system transfer real-time field data of meteorological factors, tension of conductor and acceleration of monitoring nodes to background computer. The line vibration curve integrated directly from the acceleration sensor recorded data will present a serious problem of baseline drift. Therefore, based on least-square theory, a new baseline correction method is proposed to eliminate effect on drifts, and then obtain distortion less vibration curve of transmission line by twice integrations. The system running results show that track fitted with monitoring data is in good agreement with the real recorded trajectory. The system can satisfy the needs of the real time monitoring on transmission line site and be well applied to the calculation of conductor fatigue damage.

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Cherkashуna, V. V., and V. M. Baklitsky. "IMPROVEMENT OF TECHNICAL AND ECONOMIC MODELS OF OVERHEAD LINES TRANSMISSION BASED ON CRITERIONAL METHOD." Bulletin of the National Technical University "KhPI". Series: Energy: Reliability and Energy Efficiency, no. 1 (1) (December 30, 2020): 89–94. http://dx.doi.org/10.20998/2224-0349.2020.01.13.

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Improved technical and economic models of 35–750 kV overhead lines in accordance with the Law of Ukraine "On the Electricity Market" are proposed. The urgency and complexity of the problem is due to the fact that the transition to market relations presupposes the presence of private property, where the area under the grid facility, including the route of overhead lines, is a commodity and should be taken into account in shaping the value of this facility. In this regard, there is a need to review the discounted costs in the design of lines to bring them into line with market relations. The development of a new technical and economic model of 35–750 kV overhead lines was carried out taking into account the size and cost of land under the route of the line, which allows for a feasibility study of the optimal design option for the electrical network. The specific part of the land area in the cost of 1 km of overhead lines of different voltage classes is calculated. The components of the improved technical and economic model of 35–750 kV overhead lines are determined, namely the specific part of the component costs in the total cost of 1 km overhead lines of different voltage classes. A graphical representation of generalized models of investments in 35–750 kV overhead lines is presented. The presented studies take into account that during the construction of technical and economic models it is almost impossible to predict all its internal often stochastic connections, the elements of which cannot be expressed unambiguously, which leads to incomplete source information. Based on this fact, in the article for the analysis of the developed technical and economic models of lines the criterion method which allows to make decisions in conditional units both at full and at incomplete and indefinite initial information is applied. Implementing each equation of the developed technical and economic model of 35–750 kV overhead lines by the criterion method the ratio of components in the optimal design of lines in the corresponding voltage class is obtained, which allows to determine the development strategy of electrical networks and to form restrictions in incomplete source information.

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Banu, G., and S. Suja. "Fault location technique using GA-ANFIS for UHV line." Archives of Electrical Engineering 63, no. 2 (June 1, 2014): 247–62. http://dx.doi.org/10.2478/aee-2014-0019.

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Abstract This paper presents an improved approach for locating and identifying faults for UHV overhead Transmission line by using GA-ANFIS. The proposed method uses one end data to identify the fault location. The ANFIS can be viewed either as a Fuzzy system, neural network or fuzzy neural network FNN. The integration with neural technology enhances fuzzy logic system on learning capabilities are proposed to analyze the UHV system under different fault conditions. The performance variation of two controllers in finding fault location is analyzed. This paper analyses various faults under different conditions in an UHV using Matlab/simulink. The proposed method is evaluated under different fault conditions such as fault inception angle, fault resistance and fault distance. Simulation results confirm that the proposed method can be used as an efficient for accurate fault location on the transmission line.

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Hu, Jian, Xiaofu Xiong, Jing Chen, Wei Wang, and Jian Wang. "Transient Temperature Calculation and Multi-Parameter Thermal Protection of Overhead Transmission Lines Based on an Equivalent Thermal Network." Energies 12, no. 1 (December 26, 2018): 67. http://dx.doi.org/10.3390/en12010067.

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The overload degree of a transmission line is represented by currents in traditional overload protection, which cannot reflect its safety condition accurately. The sudden rise in transmission line current may lead to cascading tripping under traditional protection during power flow transfer in a power system. Therefore, timely and accurate analysis of the transient temperature rise of overhead transmission lines, revealing their overload endurance capability under the premise of ensuring safety, and coordination with power system controls can effectively eliminate overloading. This paper presents a transient temperature calculation method for overhead transmission lines based on an equivalent thermal network. This method can fully consider the temperature-dependent characteristics with material properties, convective heat resistance, and radiation heat and can accurately calculate the gradient distribution and response of the conductor cross-section temperature. The validity and accuracy of the proposed calculation method are verified by a test platform. In addition, a multi-parameter thermal protection strategy is proposed on the basis of the abovementioned calculation method. The protection can adequately explore the maximum overload capability of the line, and prevent from unnecessary tripping to avoid the expansion of accidents. Finally, the validity of the proposed protection is verified by the modified 29-bus system.

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He, Huiwen, Lei Wang, Peihong Zhou, and Fei Yan. "Overvoltage and Insulation Coordination of Overhead Lines in Multiple-Terminal MMC-HVDC Link for Wind Power Delivery." International Journal of Rotating Machinery 2017 (2017): 1–7. http://dx.doi.org/10.1155/2017/4849262.

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The voltage-sourced converter-based HVDC link, including the modular multilevel converter (MMC) configuration, is suitable for wind power, photovoltaic energy, and other kinds of new energy delivery and grid-connection. Current studies are focused on the MMC principles and controls and few studies have been done on the overvoltage of transmission line for the MMC-HVDC link. The main reason is that environmental factors have little effect on DC cables and the single-phase/pole fault rate is low. But if the cables were replaced by the overhead lines, although the construction cost of the project would be greatly reduced, the single-pole ground fault rate would be much higher. This paper analyzed the main overvoltage types in multiple-terminal MMC-HVDC network which transmit electric power by overhead lines. Based on ±500 kV multiple-terminal MMC-HVDC for wind power delivery project, the transient simulation model was built and the overvoltage types mentioned above were studied. The results showed that the most serious overvoltage was on the healthy adjacent line of the faulty line caused by the fault clearing of DC breaker. Then the insulation coordination for overhead lines was conducted according to the overvoltage level. The recommended clearance values were given.

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Barakou, Steennis, and Wouters. "Accuracy and Reliability of Switching Transients Measurement with Open-Air Capacitive Sensors." Energies 12, no. 7 (April 11, 2019): 1405. http://dx.doi.org/10.3390/en12071405.

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Contactless capacitive (open-air) sensors are applied to monitor overvoltages near overhead line terminations at a substation or at the transition from underground cables to overhead lines. It is shown that these sensors, applied in a differentiating/integrating measuring concept, can result in excellent characteristics in terms of electromagnetic compatibility. The inherent cross-coupling from open-air sensors to other phases is dealt with. The paper describes a method to calibrate the sensor to line coupling matrix based on assumed 50 Hz symmetric phase voltages and in particular focuses on uncertainty analysis of assumptions made. Network simulation shows that predicted maximum overvoltages agree within typically 7% compared to reconstructed values from measurement, also with significant cross-coupling. Transient voltages from energization of an (extra-)high voltage connection can cause large and steep rising ground currents near the line terminations. Comparison with results obtained by a capacitive divider confirms the intrinsic capability in interference rejection by the differentiating/integrating measurement methodology.

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Benato, Roberto, Giovanni Rinzo, and Michele Poli. "Overcoming the Limits of the Charge Transient Fault Location Algorithm by the Artificial Neural Network." Energies 12, no. 4 (February 22, 2019): 722. http://dx.doi.org/10.3390/en12040722.

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In this paper, two algorithms for single-ended fault location are presented with reference to the unearthed sub-transmission Italian grid (with a voltage level of 60 kV). Both algorithms deal with the correlation between the ground capacitance charging frequency of sound phases and the fault position. In the former, the frequency response of a lumped parameter circuit in the Laplace domain is linked to the fault distance. With such a simplified lumped parameter circuit, the average error in locating a phase-to-ground (PtG) short circuit is 5.18% (total overhead line length equal to 60 km). Since this error is too high, another approach is presented. In this second algorithm, the frequency spectra of the transient current waveforms are used as a database for the training of an Artificial Neural Network (ANN). With this approach, the average error decreases significantly up to 0.36%. The fault location accuracies of the two proposed methods are compared in order to reveal their strengths and weaknesses. The developed procedures are applied to a single-circuit overhead line and to a double-circuit one, both modelled in the EMTP-rv environment, whereas the fault location algorithms are implemented in the MATLAB environment (for the ANN-based algorithm, the Deep Learning toolbox is used).

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Sidorov, Sergey, Valery Sushkov, and Ilya Sukhachev. "Development of a method for determining the location of a single line-to-ground fault of an overhead power line with voltage of 6(10) kV considering climatic factors." E3S Web of Conferences 124 (2019): 05003. http://dx.doi.org/10.1051/e3sconf/201912405003.

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One of the main causes of the high accidents and outages rate in 6(10)-kV distributed power supply systems of oil well clusters is damage to overhead power lines due to single line-to-ground faults. Widely conducted studies to locate a single line-to-ground fault have established a correlation between the accuracy of determination and a large number of changing factors, such as operating mode parameters, overhead power line parameters, type of damage, transition resistance, soil resistance, and others. Rationing of technical means for determining the location of a single line-to-ground fault by instrumental errors without taking into account the methodological component translates into the error in locating the damage up to 30%. Thus, relevant research is aimed at determining the primary parameters of power lines and minimizing the methodological error in determining the location of damaged power lines, considering climatic factors. The study takes into account the basic physical processes of propagation of an electromagnetic wave in the power line. The main principles of the theory of electrical circuits and the electromagnetic field and MATLAB Simulink package algorithms are used. As part of the study, a technique has been developed that allows determining the distance from 6(10)/0.4-kV substations to a single line-to-ground fault location in distribution networks of oil well clusters taking into account climatic factors. A simulation model of a 10-kV distribution network supplying oil well clusters was developed in MATLAB Simulink, taking into account the dependence of the primary power line parameters on climatic factors and soil resistivity.

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Ikbal, Muhamad. "TEGANGAN PEMULIHAN PADA KONTAK PEMUTUS DAYA TEGANGAN TINGGI UNTUK PROTEKSI TERHADAP GELOMBANG BERJALAN." Jurnal Qua Teknika 8, no. 1 (March 28, 2018): 11–21. http://dx.doi.org/10.35457/quateknika.v8i1.341.

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In general we have known the frequent disruption of transmission lines is a natural disturbance, such as lightning disturbance to the transmission network due to transmission network through the air, long, high and spread in various open areas and operate in all kinds of conditions. Among the considerations taken in the transmission line transmission design is the location of the ground wire against the phase wire. Because the ground wire only, so a small percentage on the phase wire. And until now there are no scholars who show the use of lightning for life, have not got a way to prevent or exploit the energy caused by the lightning. Nevertheless, human science continues to thrive with technological advances. With one safety device, an air wire (Overhead Ground Wire) to protect the phase wires from the transmission line.

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Ikbal, Muhamad. "TEGANGAN PEMULIHAN PADA KONTAK PEMUTUS DAYA TEGANGAN TINGGI UNTUK PROTEKSI TERHADAP GELOMBANG BERJALAN." JURNAL QUA TEKNIKA 8, no. 1 (March 28, 2018): 11–21. http://dx.doi.org/10.30957/quateknika.v8i1.341.

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In general we have known the frequent disruption of transmission lines is a natural disturbance, such as lightning disturbance to the transmission network due to transmission network through the air, long, high and spread in various open areas and operate in all kinds of conditions. Among the considerations taken in the transmission line transmission design is the location of the ground wire against the phase wire. Because the ground wire only, so a small percentage on the phase wire. And until now there are no scholars who show the use of lightning for life, have not got a way to prevent or exploit the energy caused by the lightning. Nevertheless, human science continues to thrive with technological advances. With one safety device, an air wire (Overhead Ground Wire) to protect the phase wires from the transmission line.

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Jia, Keyin, Cheng Wang, Shiyang Zheng, Junfeng Liu, and Minghongtian Chen. "Research and Application of Automatic Fault Diagnosis and Isolation Device for Distribution Line." E3S Web of Conferences 261 (2021): 01015. http://dx.doi.org/10.1051/e3sconf/202126101015.

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This paper takes the equipment of a specific project as an example to develop an automatic fault diagnosis and isolation device for 10kV overhead line or cable line when a user has grounding and shortcircuit faults, so as to realize fast fault location, isolation and recovery, reduce the power outage time of users, and thus improve the reliability of distribution network. The project takes the 10kV South and North Trunk Lines ‘hand in hand’ power supply network as the research object, and studies the solutions of the automatic fault isolation function and the restoration of power supply, hoping to further improve the level of rapid power recovery, reduce power loss, and improve the reliability, automation and information level of power supply for reference.

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Luo, Kewei. "Research on prediction model of construction period of overhead line project based on BP neural network." IOP Conference Series: Earth and Environmental Science 546 (August 12, 2020): 042073. http://dx.doi.org/10.1088/1755-1315/546/4/042073.

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Volokhovskiy, Vasily, Vasily Sukhorukov, and Victor Tzukanov. "Strength Assessment of Deteriorated OHL Conductors and Earth Wires Based on Non-Destructive Testing." Key Engineering Materials 569-570 (July 2013): 1156–63. http://dx.doi.org/10.4028/www.scientific.net/kem.569-570.1156.

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Safety operation of overhead lines depends on many factors including strength of conductors and earth wires. Therefore worn-out or defective conductors or earth wires must be detected. Estimation of conductor technical conditions is based on comparison of revealed flaws with requirements of overhead line project and build documentation. It is well known that conductors are affected by corrosion, friction and fatigue wear. All this factors may cause loss of strength and even breakage of conductor. Steel core is the most important part of conductor when it comes to mechanical loads. That is why it is very important to know actual technical conditions of steel core of conductor. Worn or defective wires must be repaired or replaced. Principles of strength assessment of deteriorated of steel-aluminum conductors and steel earth wires based on magnetic non-destructive testing technique are presented. The retention of overhead line conductor and earth wire is one of the most reasonable ways to eliminate the unacceptable clearances. The allowable magnifying tension, regarding the reliable operation, is set relying upon the non-destructive testing of conductors or earth wires in actual state. The measured loss of metallic cross-section area due to abrasion, corrosion etc. and local wire breaks are treated as input data for mechanical model of objects under test. The residual strength estimates give the specialists network company further information that helps to make a valid decision on testing time-limit and policy. Some results of assessing the strength of overhead line conductors and earth wires according to the NDT data are demonstrated.

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El-Sayed Gouda, Osama, and Noura Ahmed Elshesheny. "Simulation of the Lightning Back-Flashover for Medium Voltage Distribution Network." Indonesian Journal of Electrical Engineering and Computer Science 3, no. 2 (August 1, 2016): 264. http://dx.doi.org/10.11591/ijeecs.v3.i2.pp264-272.

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Lightning strikes represent a considerable cause of short interruptions in electrical overhead line networks. The over voltages caused by lightning cannot be avoided but their influence can be limited by appropriate over voltage protection. This paper presents analysis study on some factors affecting the back flashover of Egyptian 66 kV distribution lines using Alternative Transient Program (ATP). The study includes the modeling of 66 kV distribution lines, the effects of magnitude and the front and tail times of lightning wave on the back flashover voltages, the effects of the striking distance, and the using of counterpoise wires on the back flashover on the 66 kV line towers. In this paper the 66 kV lines sag is neglected and the soil ionization by the flow of the stroke current is considered.

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Pană, Adrian, Alexandru Băloi, and Florin Molnar-Matei. "Mathematical Explanations of a Paradox Observed in a HVAC (High Voltage Alternating Current) Untransposed Overhead Line." Energies 12, no. 4 (February 22, 2019): 734. http://dx.doi.org/10.3390/en12040734.

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The constructive asymmetry of the untransposed overhead lines of a high voltage alternating current is the cause of a great number of difficulties in their operation and modeling. In order to model the operating regimes of such lines, the symmetrical component method, based on constructive symmetry and thus the symmetry of the equivalent phase parameters, is inappropriate, which is why many research papers have been dedicated to either setting up improved modeling methods or to returning to phase coordinate modeling. This paper intends to justify a paradox found on some untransposed overhead lines of a high voltage alternating current during the no-load operating conditions by performing phase coordinate modeling. In such a situation, the transmission or distribution operators measured significant negative values for the active powers on one or two phases at the beginning of the lines. Considering the case of a real untransposed overhead line operating under no-load conditions, the paper starts from presenting the recorded electrical values. Then, the paper moves on to outlining the Carson’s simplified computing relations for calculating the series and shunt primitive equivalent parameters and Kron’s transformation relationships for calculating the phase equivalent parameters. After applying them to the real line, the calculation of the power flow for the no-load operating conditions, which is applied to an equivalent scheme of the line consisting of nine identical octopoles, is performed. Both the untransposed line and its transposed variant are studied here. The values of the electrical amounts obtained by the calculation for the untransposed line are basically similar to those obtained by measuring on the real line, which gives a mathematical confirmation of the so-called paradox. Its occurrence represents the effect of the asymmetry of the equivalent phase capacities, which causes a redistribution of the active powers between the phases of the network to which the overhead line operating in no-load conditions is connected.

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Li, Xiaoling, and Hai Hu. "QoS Routing Algorithm Based on Entropy Granularity in the Network Transmission." Cybernetics and Information Technologies 19, no. 4 (November 1, 2019): 61–72. http://dx.doi.org/10.2478/cait-2019-0036.

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Abstract With the rapid development of computer networks, more hosts are connected to the Internet where they could communicate with each other. The need for network service has exceeded the service capacity of the network, and the Quality of Service (QoS) is gradually declining. Based on existing Shortest Path First (SPF) algorithm, this paper proposes a new QoS required transmission path approach by considering the overhead balance of network resources. This paper uses the entropy granularity as the main line in the application of routing protocols. Firstly, it researches the optimization of routing algorithms for network load balancing resources, routing algorithms based on link traffic distributing weights, link weight optimization based on adaptive genetic algorithm and computational intelligence based on entropy granularity theory. This research proposes a method to apply entropy granularity to Open Shortest Path First (OSPF) routing, including the implementation of the method. After that, a case study is presented by using some examples.

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Lu, Di, and Jian Xin Wang. "The Analysis and Research on Electromagnetic Radiation Pollution of High Voltage Transmission Line." Advanced Materials Research 374-377 (October 2011): 8–13. http://dx.doi.org/10.4028/www.scientific.net/amr.374-377.8.

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With the development of China's power industry, many cities had renovated, expanded electricity power network ,110、220 kV and above the high voltage overhead transmission lines all around the urban areas and residential areas. As the electromagnetic radiation of high-voltage transmission lines inevitability pollute on urban environment, according to the Investigation, monitoring and analysis of high voltage, based on national standard of electromagnetic radiation, this paper proposed the controlling measures and recommendations of electromagnetic radiation. Therefore, the research that the electromagnetic radiation impact on the environmental has a very high value and academic significance.

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Singh, Eddie, Innocent E. Davidson, and Sindisiwe C. Malanda. "Lightning Performance and Economic Analysis of an Overhead 88 kV Power Delivery Network with Enhanced Protective Systems." Energies 13, no. 24 (December 10, 2020): 6519. http://dx.doi.org/10.3390/en13246519.

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Earthing and protective devices such as line surge arrestors (LSAs) play an important role in areas with high lightning occurrence for overhead HVAC lines’ performance. A lightning stroke of high magnitude can lead to back flash-overs, and the resultant power surge on the phase conductor can cause instigate the line breaker operating to extinguish the power surge. This operation of the protective devices leads to consumer interruptions on the network, a loss of production, and negatively affects the economy. Studies have shown that reducing an earthing system’s values, which itself is costly, may not be sufficient to prevent back flashover and the associated customer production cost loss. A code was developed to determine the possibility of back flashover and the cost of various earthing schemes utilizing the MATLAB software analysis tool. This paper determines the possibility of a back flashover for various combinations of lightning strokes and earthing profiles. Tower Footing Resistances as low as 9.8 Ω can cause back flashover, provided the lightning stroke exceeds 12 kA. Furthermore, the paper presents and discusses an innovative hybrid power line protection scheme, which estimates and considers the high cost associated with establishing an earthing system; it examines the impracticality of re-engineering an earthing scheme for implementation and results obtained by the inclusion of lightning surge arrester’s (LSA). The cost-saving resulting from dips is also established over 25 years for an 88 kV line, and the breakeven point is established. The results showed that the best scenario would be to reduce the tower footing resistance to 29.1 Ω and install 11 LSA per phase.

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Journal articles on the topic 'Overhead line network'

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