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CSEE Journal of Power and Energy Systems 2024年第1期10卷 351-360页

作者： Xianglong Lian Tong Qian Zepeng Li Xingyu Chen Wenhu Tang Q.H.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China

In power systems,failures of vulnerable lines can trigger large-scale cascading failures,and vulnerability assessment is dedicated to locating these lines and reducing the risks of such *** on a structure and attribute network embedding(SANE)algorithm,a novel quantitative vulnerability analysis method is proposed to identify vulnerable lines in this ***,a two-layered random walk network with topological and electrical properties of transmission lines is ***,based on the weighted degree of nodes in the two-layered network,the inter-layer and intra-layer walking transition probabilities are developed to obtain walk ***,a Word2Vec algorithm is applied to obtain lowdimension vectors representing transmission lines,according to obtained walk sequences for calculating the vulnerability index of transmissions ***,the proposed method is compared with three widely used methods in two test *** show the network embedding based method is superior to those comparison methods and can provide guidance for identifying vulnerable lines.

关键词： Network embedding random walk transmission lines vulnerability assessment

Steady-state Voltage Reactive Compensation Method for Half-wavelength transmission lines Considering Equivalent Power Supply Impedance

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CSEE Journal of Power and Energy Systems 2020年第4期6卷 841-847页

作者： Jun Yi Wei Hu Zijie Zhang Lu Qiu Ansi Wang Bowen Yan Canbing Li Quanyou Yue China Electric Power Research Institute Beijing 100192China State Key Laboratory of Department of Electrical Engineering Tsinghua UniversityBeijing 100084China Hunan Key Laboratory of Intelligent Information Analysis and Integrated Optimization for Energy Internet Hunan UniversityChangsha 410006China Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Half-wavelength AC transmission(HWACT)refers to transmission along lines with an electrical distance of half the power frequency *** voltage amplitude at the sending terminal is equal to that at the receiving terminal in ***,the voltage at the receiving terminal does not vary with ***,the electrical distance has been extended in actual HWACT lines because of the impact of the equivalent power supply impedance,so the attractive characteristics no longer *** a result,reactive power compensation methods with constant power factor and constant voltage are needed and these are presented in this *** steady-state operational characteristics,the calculation methods of additional reactive power compensation and the admittance of a controllable shunt reactor are also *** methods proposed in this paper are relatively simple to implement,and the calculations involved are straightforward,resulting in effective voltage *** results indicate that such compensation methods can increase the transmission capacity while maintaining a relatively low voltage along the line.

关键词： half-wavelength AC transmission(HWACT) reactive power compensation steady state transmission lines

Mechanical response of transmission lines based on sliding cable element

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Journal of Central South University 2014年第8期21卷 3370-3377页

作者：刘云钱振东夏开全 College of Civil and Transportation Engineering Hohai University Intelligent Transportation System Research Center Southeast University China Electric Power Research Institute

In order to study the sliding characteristics when the cable is connected with the other rods in the transmission line structures,a linear sliding cable element based on updated Lagrangian formulation and a sliding catenary element considering the out-of-plane stiffness coefficient are put forward.A two-span and a three-span cable structures are taken as examples to verify the sliding cable *** comparing the tensions of the two proposed cable elements with the existing research results,the error is less than 1%,which proves the correctness of the proposed *** sliding characteristics should be considered in the practical engineering because of the significant difference between the tensions of sliding cable elements and those of cable element without considering *** out-of-plane stiffness coefficient and friction characteristics do not obviously affect the cable tensions.

关键词： transmission lines sliding cable element updated Lagrangian formulation geometric nonlinearity mechanical response

Dynamic Analysis of Overhead transmission lines under Turbulent Wind Loading

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Open Journal of Civil Engineering 2015年第4期5卷 359-371页

作者： Alok Dua Mathias Clobes Thomas Hobbel Vasant Matsagar Department of Civil Engineering Indian Institute of Technology(IIT)DelhiIndia Institut fur Stahlbau Technische Universitat Carolo‐WilhelminaBraunschweigGermany

transmission tower-line systems are designed using static loads specified in various codes. This paper compares the dynamic response of a test transmission line with the response due to static loads given by Eurocode. Finite element design software SAP2000 was used to model the towers and lines. Non-linear dynamic analysis including the large displacement effects was carried out. Macroscopic aspects of wind coherence along element length and integration time step were investigated. An approach is presented to compare the probabilistic dynamic response due to 7 different stochastically simulated wind fields with the response according to EN-50341. The developed model will be used to study the response recorded on a test line due to the actual wind speed time history recorded. It was found that static load from EN overestimated the strength of conductor cables. The response of coupled system considering towers and cables was found to be different from response of only cables with fixed supports.

关键词： Dynamic Analysis Finite Element Method SAP2000 transmission Towers transmission lines

Analytical Frequency-Dependent Model for transmission lines on RF-CMOS Lossy Substrates

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Tsinghua Science and Technology 2007年第6期12卷 752-756页

作者：叶佐昌喻文健余志平 Institute of Microelectronics Tsinghua University Department of Computer Science and Technology Tsinghua University

transmission lines （T-lines） are widely used in millimeter wave applications on silicon-based complementary metal-oxide semiconductor （CMOS） technology. Accurate modeling of T-lines to capture the related electrical effects has, therefore, become increasingly important. This paper describes a method to model the capacitance and conductance of T-lines on CMOS multilayer, Iossy substrates based on conformal mapping, and region subdivision. Tests show that the line parameters （per unit length） obtained by the method are frequency dependent and very accurate. The method is also suitable for parallel multiconductor interconnect modeling for high frequency circuits.

关键词： transmission lines frequency dependence capacitance radio frequency complementary metaloxide semiconductor (RF-CMOS) circuit characteristics

State Inspection for transmission lines Based on Independent Component Analysis

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Journal of Shanghai Jiaotong university(Science) 2009年第2期14卷 129-132页

作者：任丽佳江秀臣盛戈嗥杨巍巍 Department of Electrical Engineering Shanghai Jiaotong University Urban Power Supply Company Shanghai Municipal Electric Power Company Northeast China Grid

Monitoring transmission towers is of great importance to prevent severe thefts on them and ensure the reliability and safety of the power grid *** component analysis(ICA) is a method for finding underlying factors or components from multivariate statistical data based on dimension reduction methods,and it is applicable to extract the non-stationary *** based on negentropy is presented to effectively extract and separate the vibration signals caused by human activity in this paper.A new method combined empirical mode decomposition(EMD) technique with the adaptive threshold method is applied to extract the vibration pulses,and suppress the interference *** practical tests demonstrate that the method proposed in the paper is effective in separating and extracting the vibration signals.

关键词： state inspection transmission lines independent component analysis (ICA) negentropy adaptive threshold empirical mode decomposition (EMD)

Progress in research on ice accretions on overhead transmission lines and its influence on mechanical and insulating performance

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Frontiers of Electrical and Electronic Engineering in China 2012年第3期7卷 326-336页

作者： Shaohua WANG Xingliang JIANG Zhejiang Electric Power Test and Research Institute Hangzhou 310014China College of Electrical Engineering Chongqing University Chongqing400044 China

Atmospheric ice accretion on transmission lines is of great danger to the security of service of electrical power system. This paper reviews the progress in research dealing with the formation of ice accretions on transmission lines and the effects of ice on the mechanical and electrical performance of transmission lines. The results show that ice accretions on transmission lines can be categorized into five types： glaze, hard rime, soft rime, hoar frost, and snow and sleet. In all types of ice accretions, glaze grown in a wet regime is of the greatest danger to the transmission lines. Meteorological conditions, terrain and geographic conditions, and some other factors significantly influence the ice accumulation speed and the ice amount. Drastic decrease of mechanical property and electric property as a result of severe icing is the main reason for ice accidents. The amount of ice, the asymmetrical ice accretion, and the asynchronous ice shedding can considerably change the conductor strain, conductor sag, variation amount of the span, displacement of the insulator string, and the tension difference. The amount and type of ice, the uniformity of ice accumulation, and the con- ductivity of freezing water have significant influence on the flashover voltage of ice-covered insulators.

关键词： transmission lines icing mechanical perfor-mance electrical performance

Fiber Bragg grating monitors for thermal and stress of the composite insulators in transmission lines

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Global Energy Interconnection 2018年第3期1卷 382-390页

作者： Heming Deng Wei Cai You Song Jinsong Liu Christopher Redman Qiandong Zhuang NARI Group (State Grid Electric Power Research Institute) co.ltd State Grid Xinjiang Electric Power Company Physics department Lancaster University

Running composite insulators are prone to failure due to their harsh surrounding work environment, which directly affects the safe operation of transmission lines. This paper puts forward the method of using fiber Bragg grating(FBG) as the monitors to parameters correlated with thermal and stress of the composite insulators in transmission lines at working status. Firstly, monitoring points are found out by the mechanical test on composite insulator samples. Secondly, based on the monitoring theory, this paper introduces the feasibility design frame of the composite insulator with FBG implanted in the rod and the online monitor system. At last, it describes applications of this monitor system in the field of transmission lines.

关键词： Thermal monitoring Stress monitoring Composite insulators transmission lines Fiber Bragg grating monitors

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Multi-transmission lines Loaded by Linear and Nonlinear Lumped Elements： FDTD Approach

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Journal of Electrical Engineering 2017年第2期5卷 67-73页

作者： Ismail ALAOUI ABDALLAOUI Hassane KABBAJI Philippe DESCAMPS ~idi Mohammed Ben Abdellah University -LSSC-B.P. 2202- Route d'Immouzzer Fes Morocoo Normandie University ENSICAEN CRISMA T UMR6580. 6 boulevard Marechal Juin 14050 Caen cedex 04 France

In this paper, we are interested on studying the Multi-transmission lines, the analysis is ensured by the FDTD （finite difference temporal domain） method combined with the ABC （absorbing boundary conditions） to predict the current and voltage behavior resulting from the electromagnetic fields all along lines. Simulated results will be compared to commercial software to validate the proposed algorithm.

关键词： transmission lines FDTD method ABC-PML Maxwell equations lumped elements

Minimization of Electric Power Losses on 132 kV and 220 kV Uganda Electricity transmission lines

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Energy and Power Engineering 2023年第2期15卷 127-150页

作者： Ounyesiga Living Stephen Ndubuisi Nnamchi Kelechi John Ukagwu Abubakar Abdulkarim Zaid Oluwadurotimi Jagun Department of Electrical Telecom and Computer Engineering SEAS Kampala International University Kampala Uganda Department of Mechanical Engineering SEAS Kampala International University Kampala Uganda Department of Electrical Engineering Faculty of Engineering Ahmadu Bello University Zaria Nigeria Department of Computer Engineering Olabisi Onabanjo University Ago-Iwoye Nigeria

The classical minimization of power losses in transmission lines is dominated by artificial intelligence techniques, which do not guarantee global optimum amidst local minima. Revolutionary and evolutionary techniques are encumbered with sophisticated transformations, which weaken the techniques. Power loss minimization is crucial to the efficient design and operation of power transmission lines. Minimization of losses is one way to meet steady grid supply, especially at peak demand. Thus, this paper has presented a gradient technique to obtain optimal variables and values from the power loss model, which efficiently minimizes power losses by modifying the traditional power loss model that combines Ohm and Corona losses. Optimality tests showed that the unmodified model does not support the minimization of power losses on transmission lines as the Hessian matrix portrayed the maximization of power losses. However, the modified model is consistent with the gradient method of optimization, which yielded optimum variables and values from the power loss model developed in this study. The unmodified (modified) models for Bujagali-Kawanda 220 kV and Masaka West-Mbarara North 132 kV transmission lines in Uganda showed maximum power losses of 0.406 (0.391) and 0.452 (0.446) kW/km/phase respectively. These results indicate that the modified model is superior to the unmodified model in minimizing power losses in the transmission lines and should be implemented for the efficient design and operation of power transmission lines within and outside Uganda for the same transmission voltages.

关键词： Minimization Power Losses transmission lines Corona and Ohms Losses transmission Model