Electric Power Transmission Lines Research Articles

Multiple Fault Detection and Diagnosis in Electric Power Transmission Lines

Multiple Fault Detection and Diagnosis in Electric Power Transmission Lines

Soft Computing Methods for Fault Detection in Power Transmission Lines

Communication is a major aspect of our day to day life and for maintaining the transmission of the data; electric power transmission lines play a major role in acting as the medium for this transmission. The transmission lines can further be differentiated as an overhead transmission line and underground transmission line. But the transmission is often hindered by the physical factors or generally known as faults. In the past few years, the implementation of the underground cable has seen an upsurge as these cables are not easily affected by the physical factors as the overhead cables are, as a result, there have been various methods adopted by the engineers for the analysis, detection and control of these faulty lines. Depending on the supply range of a particular nation different materials are used for the transmission lines. Different fault detection methods are used for the exact location of the fault and implementing that in a digitized way is the optimum solution. Whenever there is a fault the entire transmission line is affected, to ensure that the safety of the transmission line a governing system has been implied in our proposed work. Locating a fault requires various detection methods, one such method is the time domain reflectometry (TDR) which we have inculcated in our analysis of fault lines. This technique incorporates the transmission of a pulse down the cable, any change in the characteristics impedance will cause a part of the incident pulse to reflect back, this knowledge is helpful for locating discontinuities in a system.

Analysis of Electric Power Transmission Line Presenting Only Long-Wise Inductance

Analysis of Electric Power Transmission Line Presenting Only Long-Wise Inductance

Analysis of Electric Power Transmission Line Resultant Wave Current in Polar Form

Analysis of Electric Power Transmission Line Resultant Wave Current in Polar Form

Analysis of Electric Power Transmission Line Wave Voltage Components in Polar Form

Analysis of Electric Power Transmission Line Wave Voltage Components in Polar Form

Hybrid Pattern Recognition and Multi-resolution Analysis (MRA) Based Fault Location in Power Transmission Lines

This paper proposes a fault (line-to-line) location on Ikeja West – Benin 330kV electric power transmission lines using wavelet multi-resolution analysis and neural networks pattern recognition abilities. Three-phase line-to-line current and voltage waveforms measured during the occurrence of a fault in the power transmission-line were pre-processed first and then decomposed using wavelet multi-resolution analysis to obtain the high-frequency details and low-frequency approximations. The patterns formed based on high-frequency signal components were arranged as inputs of the neural network, whose task is to indicate the occurrence of a fault on the lines. The patterns formed using low-frequency approximations were arranged as inputs of the second neural network, whose task is to indicate the exact fault type. The new method uses both low and high-frequency information of the fault signal to achieve an exact location of the fault. The neural network was trained to recognize patterns, classify data and forecast future events. Feed forward networks have been employed along with back propagation algorithm for each of the three phases in the Fault location process. An analysis of the learning and generalization characteristics of elements in power system was carried using Neural Network toolbox in MATLAB/SIMULINK environment. Simulation results obtained demonstrate that neural network pattern recognition and wavelet multi-resolution analysis approach are efficient in identifying and locating faults on transmission lines as the average percentage error in fault location was just 0.1386%. This showed that satisfactory performance was achieved especially when compared to the conventional methods such as impedance and travelling wave methods.

A fuzzy goal programming method to solve congestion management problem using genetic algorithm

The objective of this work is to present a priority-based fuzzy goal programming (FGP) method for solving the congestion management (CM) problem in electric power transmission lines by employing genetic algorithm (GA). To formulate the model for this problem, membership functions which are associated with the fuzzy model goals are converted into membership goals by assigning highest membership value (unity) as goal level and adding under- and over-deviational variables to each of them. In solution process, a GA computational scheme is addressed within the framework of FGP model to achieve aspired goal levels of goals according to their priorities in imprecise environment. The standard IEEE 30-Bus 6-Generator test system is taken as a case example to show the effectiveness of the approach. A comparison of model solution is also compared with solution of another approach studied previously.

Predictive machine learning and data acquisition for power quality improvement in facts devices with optimum power flow control based on cross difference progression and coordination examining algorithm

Flexible AC Transmission Systems (FACTS) present a decision to issue trouble relief for over-extended electric power transmission lines as a result of optimal power flow (OPF) by controlling. To keep away from conventional impacts among a few gadgets placed in a similar grid, an organized control is fundamental. To defeat the issues which happen in optimal power flow to actualize the cross difference progression and coordination inspects strategy, a supervisory controller giving difference progression power flow with numerous destinations is acquired for avoiding congestion, it gives secure transmission and farthest point dynamic power misfortunes. There is no information on gadgets that have been defined in this systematic control of Thyristor controlled series capacitor (TCSC) and Thyristor controlled phase shifting Transformer (TCPST), static VAR compensator (SVC), all of these compensators providing efficient improvements and situations are described. Different optimization techniques are used as a part of the character to deal with the problem of OPF. In some experimental works, the upgrade method is used for finding out all of the fuel costs or the environmental pollution that occurs during the generation of energy. However, in some further research actions, FACTS controlled devices are used to develop the flow of electricity without considering the cost of electricity generation. While a specific end goal of using the FACTS control devices is to help optimize the congestion in the power system, it also aggregates the power loss which enhances the load capacity of the structure. The FACTS and its practical limitations are executed into the IEEE 30-bus test power framework and customized utilizing the Cross Difference Progression and Coordination Examining (CDP&CE) algorithm with MATLAB and the outcomes are given. Here, IoT-based data analytics is defined as the process, which is used to examine varied data from the bus system using Principal Component Analysis (PCA) method, the results of which help to take the necessary decisions. The effect of FACTS gadgets is implemented on standard IEEE-30 transmission framework with supporting numerical outcomes by utilizing MATLAB Software.

Investigating tension in overhead high voltage power transmission line using finite element method

Transmission line failure is a serious problem in developing countries. The major cause of high voltage overhead transmission line failure in power system is prolonged excessive current. The determination of line segments where high tension is generated due to prolonged excessive current under the different arrangements of line spacing and current carrying conditions can lead us to analyze high tension zones for efficient design of transmission lines. In this context, the mechanical tension on an overhead high voltage electrical power transmission line resulting from excessive or normal currents was computed using Finite Element Method. Multiple segments of a long transmission line with symmetrical and unsymmetrical spacing under accidental and normal line current are examined. Therein, the line segments with high tension are determined. Maximum integrated tension is found in middle segments of both symmetrical and unsymmetrical spaced transmission line. While, maximum per unit tension is found in initial and bottom segments. However, variation in magnitude is found for symmetrical and unsymmetrical spacing. The present study may provide technical guidance to the transmission line design engineers and technicians regarding the risk and solutions related to electrical power transmission line systems.

The Dynamic Effect of Downburst Winds on the Longitudinal Forces Applied to Transmission Towers

Electric power transmission line systems are a key component in the development of our modern societies. The uninterrupted availability of electric power mandates building transmission line structures that can withstand severe natural hazards. The current study focuses on the performance of conductor line systems subjected to downburst loading, which along with other types of wind events are responsible for 80% of weather related failures of transmission lines. Due to the special configuration of downburst wind fields, a unique failure mode of transmission line structures can be found to damage the cross-arms of the supporting towers as a result of the development of longitudinal forces in the conductor lines. The main concern of the current study is to explore the dynamic effect of downburst loading on these longitudinal forces, and to examine the validity of using quasi-static analysis. This is done through two levels of analysis, model-scale and full-scale. The model-scale analysis is first used to propose a simulation technique that can predict the dynamic response of conductor systems due to downburst loading overcoming the complexity induced by time varying aerodynamic damping coefficients. The proposed model is validated using a unique experiment conducted at WindEEE dome testing facility at The University of Western Ontario in Canada. The validated model is used to conduct analysis at the full-scale level using a wind field generated by a Computational Fluid Dynamics (CFD) model. Results show that the longitudinal forces within the conductor system are dynamically insensitive and can therefore be treated quasi-statically. Lastly, to judge the applicability of the wind field used, a comparison was made between the CFD wind field and full-scale records. The comparison was done through two parameters that would affect the quasi-static response; the first relating the peak velocity to the post peak velocity, and the second defining the ramping period. It was concluded from the comparison that varying the defined parameters would result in a maximum difference of 5% in the computed reactions.

Minimizing Losses During Natural Gas Transportation

Abstract The processes of supplying natural gas are accompanied by significant losses. In this regard, the complex problem of minimizing losses and improving the efficiency of energy use is very relevant. Steel pipelines for transportation of oil and gas often cross the tracks or are located parallel to the lines of electric power transmission lines of alternating current. Most dangerous from the corrosive point of view of the combination of the chemical composition of the soil electrolyte and the vagal current density were established.

Determining Health Index of Transmission Line Asset using Condition-Based Method

Assessment of overhead transmission lines is a crucial task in the asset management of electric power infrastructures. Any assets have different life spans and require proper assessment and maintenance actions. Disruption of the power supply may cause national problems. Therefore, it is essential to ensure that the distribution and transmission of electric power from the power plant to end consumers is achieved without fail. This paper presents a proposed framework of health index of the transmission line using a condition-based method. This study refers to previous methods in determining the health index of electrical power assets, mainly transformer and transmission line. Three main indicators contributed and need to be considered in determining the health index. The indicators are structural, electrical and environmental aspects. The health index of these three indicators with 14 items was calculated, and the overall health index of the transmission line determined. From the case study conducted for this study, the specific location, tower and item can be acknowledged that cause the failure and the service interruption of energy supply to the consumer. It is found that the implementation of the health index calculation gives a more accurate description of the health status of a transmission line. The health index can be used for the prioritizing of maintenance, refurbishment or replacement to avoid disruption.

РОЗРОБЛЕННЯ ТА ДОСЛІДЖЕННЯ СИСТЕМИ КЕРУВАННЯ ЕЛЕКТРОПЕРЕДАЧІ ДИЗЕЛЬ-ПОЇЗДА НА ОСНОВІ МЕТОДІВ ЦИФРОВОГО УПРАВЛІННЯ

Розглянуті питання розробки та дослідження моделей систем автоматичного керування (САК) електропередачею дизель-поїзда з електроприводом змінного струму. Проведено огляд літературних джерел на задану тематику та аналіз існуючих підходів до розв’язання. Розглянуті як стандартні алгоритми керування окремих контурів системи управління так і варіанти з використанням методів цифрового управління. Побудовані математичні моделі, структурні схеми моделей контурів САК електропередачі, запропоновані рекурентні співвідношення для окремих контурів управління, проведене моделювання їхнього функціонування. Отримані аналітичні співвідношення, які можуть бути використані для розробки структури САК електропередачі дизель-поїзда і розрахунку її параметрів при забезпечені певного критерію якості. Визначені параметри САК вихідної напруги інверторів (каналу формування струму) асинхронного електродвигуна, які забезпечують задану якість керування та допустимі межі зміни параметрів САК.

The effects of electric power lines on the breeding ecology of greater sage-grouse.

Anthropogenic infrastructure can negatively affect wildlife through direct mortality and/or displacement behaviors. Some tetranoids (grouse spp.) species are particularly vulnerable to tall anthropogenic structures because they evolved in ecosystems void of vertical structures. In western North America, electric power transmission and distribution lines (power lines) occur in sagebrush (Artemisia spp.) landscapes within the range of the greater sage-grouse (Centrocercus urophasianus; sage-grouse). The U.S. Fish and Wildlife Service recommended using buffer zones near leks to mitigate the potential impacts of power lines on sage-grouse. However, recommended buffer distances are inconsistent across state and federal agencies because data are lacking. To address this, we evaluated the effects of power lines on sage-grouse breeding ecology within Utah, portions of southeastern Idaho, and southwestern Wyoming from 1998–2013. Overall, power lines negatively affected lek trends up to a distance of 2.7 and 2.8 km, respectively. Power lines died not affect lek persistence. Female sage-grouse avoided transmission lines during the nesting and brooding seasons at distances up to 1.1 and 0.8 km, respectively. Nest and brood success were negatively affected by transmission lines up to distances of 2.6 and 1.1 km, respectively. Distribution lines did not appear to affect sage-grouse habitat selection or reproductive fitness. Our analyses demonstrated the value of sagebrush cover in mitigating potential power line impacts. Managers can minimize the effects of new transmission power lines by placing them in existing anthropogenic corridors and/or incorporating buffers at least 2.8 km from active leks. Given the uncertainty we observed in our analyses regarding sage-grouse response to distribution lines coupled with their role in providing electric power service directly to individual consumers, we recommend that buffers for these power lines be considered on a case-by-case basis. Micrositing to avoid important habitats and habitat reclamation may reduce the potential impacts of new power line construction.

Bargaining local compensation payments for the installation of new power transmission lines

This paper analyzes transmission system operator (TSO)-host community negotiations over an efficient and socially-optimal compensation payment for the installation of new electric power transmission lines. We consider that the TSO has an incentive to negotiate over a transfer that will become a function of final demand. We thus develop a bargaining game within a vertical relationship framework to include the distribution system operator (DSO) and the end-users at the downside of the bargaining problem. We determine the equilibrium of the game, for three negotiation protocols (sequential, bilateral, and multilateral) as an alternative to the non-cooperative situation. We show that when the number of municipalities involved in the process is higher than 5, the multilateral bargaining procedure is the most profitable for all agents, including the municipalities. Inversely, when the number of municipalities is lower than 5, different cases can arise. A single municipality will prefer the non-cooperative outcome while municipalities will prefer the sequential case when there are 2 or the bilateral case when there are 3 or 4. However, from the TSO standpoint and for the society, multilateral negotiations are always the best outcome.

Development of an alternating electrical current meter mobile for low and high voltage: polarimetric analysis, mathematical model, design, and field tests

The measurement of current in electric power transmission lines is crucial for the electrical sector, thus demanding optimal control of the system. Such tasks can be carried out by optical sensors. We present a polarimetric study of an electric current sensor using magneto-optical crystal, as well as the complete development of a mobile optical meter for electric current in low- and medium-voltage lines. Based on our polarimetric study of the optical sensor (transducer), we discuss and compare Faraday rotation levels with the developed mathematical model, presenting a peak-to-peak amplitude variation of 1.8534 in the plane of polarization of light. The development of the transducer is described considering the measurement curves, calibration, linearity analysis, design of the mechanical structure, construction of the electronic structure of data acquisition, and the complete structure of the device. In the end, we present a field test. For the measurements carried out in the laboratory, the sensor presented a linear behavior with sensitivity of 2.4 mV / A, as well as a high degree of linearity, in comparison to a device with a linearity of 0.001 A. In addition, we show the development of the optical, mechanical, and electronic structures of the device, as well as field measurements in a distribution line of 13.8 kV. The measurements were performed in an energized line, and presented values compatible with those read in the feeder of the distribution company. At the time, the measured current was 220 A. Therefore, this work is presented as a solution for the realization of safe actions in certain high-voltage lines for companies that operate at high-voltage levels, primarily electric power distribution companies.

Monitoring electromagnetic fields and safe operation levels in electrical power transmission lines

Electrical power systems and their elements such as power transformers, transmission lines, capacitors, reactors and other elements, during normal operation generates electromagnetic fields that changes according with design, equipment distribution, current and voltage operation levels. This paper describes the monitoring electromagnetic fields and safe operation levels in electrical power transmission and distribution lines during the last five years in power lines located in warm climate with high salinity, corrosion and pollution level. A literature review was considered during the study. This paper characterizes power lines in order to guarantee safe operation to occupational exposure and general public since planning process. Results will be used in order to characterize power lines and will be used as a tool for utilities with the aim to reduce legal penalties and promote social responsibility. Results also were contrasted with International Commission on Non-Ionizing Radiation Protection (ICNIRP) recommendations with the reference levels for occupational exposure to time-varying electric and magnetic fields. Results provide recommendations for electrical grid utilities also the study compare real values with simulated values in order to guarantee an acceptable approach according with ICNIRP and international standards recommendations.

Reconstruction of Extensive Post-Electric Burn Scalp Defects With Exposed Bones: A Study of 12 Cases.

The scalp is a unique part of the human body with respect to its shape and position. It is the part of the body that is usually exposed in its original form, with no covering by any means of clothing. In workplaces, especially in the electrical industry in the area of electrical substations and power transmission lines it is this part of the body that can easily come in contact with high tension electrical wires. Others who can be prone to suffer such injuries are pedestrians, people working on heights, ladies hanging clothes on terraces.This case series includes 12 patients who sustained high-voltage electric burn injury to the scalp. Of the reconstructive options used, 2 were free flaps, 1 was a distant flap, and 9 were local flaps. Of the 2 free flaps, there was loss of 1 free flap due to thrombosis, which was later reconstructed with extracorporeal radial forearm flap.Of the 9 local flaps, therewas partial flap necrosis in 2 cases, which required debridement and the wounrds healed secondarily. There was recurrent osteomyelitis in 1 patient who underwent sequestrectomy. In conclusion, the results obtained, in all the patients, were satisfactory without necessitating a bony reconstruction.

Optimal statistical calculation of power cables disposition in tunnels, for reducing magnetic fields and costs

The allocation of electric power transmission lines in tunnels is a common practice in several applications, like underground lines in urban areas, connections of cables to substations, mining and railway systems. Construction of tunnels requires difficult and costly works. Besides, limitations of external and internal magnetic fields generated by the currents in the cables of the tunnel are needed. The present paper proposes and analyzes different statistical methods for calculation of optimal dispositions of cables and tunnel dimensions for reducing magnetic field and costs, for time varying currents in the cables. The implementation of these methods to a four-circuit real case probes their effectiveness.

Study on Unified Reference Source Phase-Check Technology Based on Synchronized Phasor Measurement

In the power system, the phase-check is a simple but very important work. The newly built, transformed and expanded power plant, transformer substation electrical equipment and power transmission lines before put into operation must be carried out phase-check test, in order to ensure voltage phase sequence and phase correct. At present, there are some limitations of traditional phase-check technology in China. In this paper, we study the method of unified reference source based on synchronized phasor measurement technology. Through the GPS time synchronization signal to realize synchronous sampling of source voltage signal in different regions, by comparing to the phase of a fixed reference source signal in the power network to determine the phase relationship between any two different power points, and thus to complete the work of phase-check. The unified reference source phase-check method based on the synchronized phasor measurement technique is simple, easy to operate, and has high efficiency, which has unique advantages. And wide area power grid phase-check can be realized.