Search

Some previous research showed that average daily exposure to extremely low frequency (ELF) magnetic fields (MF) of more than 0.3 or 0.4 μT could potentially increase risk of childhood leukaemia.

The work proposes an original method for modeling and simulating the triggering of 110 kV interconnection power lines in case of common faults, such as transient or persistent faults. Urban and industrial areas, surrounding urban areas, require a high energy consumption that is being supplied through 110 kV overhead power lines, responsible for distributing power to the industrial and domestic consumers. High voltage distribution power lines are most prone to failure, due to their exposure, affecting a large number of consumers if a fault occurs. Faults of power lines in service certify that currently there is no perfectly controllable operation mode in terms of load rating, environmental factors, insulation resistance, or mechanical resistance, which would allow total avoidance of faults, it is only possible to reduce the impact they have on the network as a whole. Mathematical models have been developed to determine the experimental voltage and current responses describing the fault propagation, expressed as a 7th-degree polynomial curve, as a second-order transfer function or as the Gaussian model type. By comparing these mathematical models, the most probable answers that can lead to the development of a control structure for rapid identification of a fault were obtained, with the possibility of triggering the line protection relay. In the final part of the manuscript, the viability of applying artificial intelligence techniques, for the approached fault management application, is proven. The developed control structure evaluates the nature of the fault and determines a faster reaction of the line protection causing an increase in the performance of the distribution service. [ABSTRACT FROM AUTHOR]

This paper presents a novel installation protocol to build a reliable and economical line monitoring system on high voltage power lines. The proposed method is able to iteratively determine the required number of sensors and their installation location for a predefined level of risk. First, it requires a general analysis of the transmission line, which ends with a critical span analysis. Then the risk arising from the variability of weather parameters along the transmission line must be determined. Finally, it is necessary to consider what kind of problem the thermal overheating can cause at the conductor (sagging, annealing) and which additional stages can be used to reduce the risk factor to the permissible level. A case study was investigated with the data of a Central-European high voltage power line to present how the proposed method works. The results showed that there are power lines on which only distributed sensor installation concepts result in a safe and economical solution. Applying the proposed method, a comprehensive and robust sensor system can be implemented, which can be a solid basis for any dynamic line rating (DLR) system.

• A novel mobile robot is designed to remove debris from high-voltage power lines. • A novel mobile robot that can be integrated with a drone for transportation. • A mobile robot was developed and tested in high-voltage power lines up to 138 kV. The importance of electrical energy in human life has grown considerably, resulting in a great surge in demand for this energy form. As a consequence, numerous power transmission lines are continuously under construction. Periodic inspections and maintenance of equipment and accessories associated with these lines are crucial to ensuring their proper functioning. Thus, this paper introduces a novel mobile robot designed to remove debris from high-voltage power lines up to 138 kV. This robot offers several advantages, including reduced costs related to maintenance operations that require specialized human labor, increased task efficiency, and reduced risks to human physical integrity by eliminating the need for manual tasks in direct contact with high-voltage lines. This paper outlines the development and validation of a novel robot that can be integrated with a drone for transportation, bringing an innovation to the format for carrying out maintenance in the electric power distribution system. After reviewing robots applied to debris removal, our study presents the novel robot's design and control system. The robot was developed and tested in both simulated and real environments, proving to be efficient and cost-effective in improving debris removal from high-voltage lines while ensuring linemen's safety. [ABSTRACT FROM AUTHOR]

The work proposes an original method for modeling and simulating the triggering of 110 kV interconnection power lines in case of common faults, such as transient or persistent faults. Urban and industrial areas, surrounding urban areas, require a high energy consumption that is being supplied through 110 kV overhead power lines, responsible for distributing power to the industrial and domestic consumers. High voltage distribution power lines are most prone to failure, due to their exposure, affecting a large number of consumers if a fault occurs. Faults of power lines in service certify that currently there is no perfectly controllable operation mode in terms of load rating, environmental factors, insulation resistance, or mechanical resistance, which would allow total avoidance of faults, it is only possible to reduce the impact they have on the network as a whole. Mathematical models have been developed to determine the experimental voltage and current responses describing the fault propagation, expressed as a 7th-degree polynomial curve, as a second-order transfer function or as the Gaussian model type. By comparing these mathematical models, the most probable answers that can lead to the development of a control structure for rapid identification of a fault were obtained, with the possibility of triggering the line protection relay. In the final part of the manuscript, the viability of applying artificial intelligence techniques, for the approached fault management application, is proven. The developed control structure evaluates the nature of the fault and determines a faster reaction of the line protection causing an increase in the performance of the distribution service.

Aim. The synthesis of single-circuit system of active shielding of magnetic field, generated by group of high voltage power lines, with different spatial arrangement of shielding coil. Methodology. The synthesis is based on the decision of a multi-criteria stochastic game, in which the vector payoff is calculated on the basis of the Maxwell equations solutions in the quasi-stationary approximation. The game decision is based on the stochastic multiagent optimization algorithms by multiswarm particles. The initial parameters for the synthesis of active shielding system are the location of the high voltage power lines with respect to the shielding space, geometry and number of shielding coils, operating currents, as well as the size of the shielding space and normative value magnetic flux density, which should be achieved as a result of shielding. The objective of the synthesis of the active shielding system is to determine their number, configuration, spatial arrangement, wiring diagrams and shielding coils currents, setting algorithm of the control systems as well as the resulting of the magnetic flux density value at the points of the shielding space. Results. Three variant of single-circuit robust system of active shielding with different spatial arrangement of shielding coil synthesis results for reduction of a magnetic field generated by group of high voltage power lines is given. The possibility of a significant reduction in the level of magnetic flux density of the magnetic field source within and reducing the sensitivity of the system to uncertainty of the plant parameters is given. Originality. For the first time carried out the synthesis, theoretical and experimental research of the robust system of active shielding of magnetic field generated by group of high voltage power lines with different spatial arrangement of compensation coil. Practical value. Practical recommendations from the point of view of the practical implementation on reasonable choice of the spatial arrangement of shielding coil of robust single-circuit system of active shielding of the magnetic field generated by the group of high voltage power lines is given.

The purpose of the work is the development of the method for the synthesis of a robust feed-forward active shielding system of the magnetic field, generated by high voltage power lines for reducing the initial magnetic field induction to the sanitary standards level and decreasing the system sensitivity to the plant parameters’ variations. This work is devoted to the solution of a multicriterion stochastic game, in which the vector payoff is calculated based on the Maxwell equations solutions in the quasi-stationary approximation. The multicriterion game solution depends on the multiswarm particles optimization algorithms. The initial parameters for the synthesis of the active shielding system are the location of the high voltage power lines with respect to the protected from transmission line space, geometry and number of buses, operating currents, as well as the size of the protected space and magnetic field induction normative value. The aim is achieved by determination of the number, configuration, spatial arrangement, and currents in compensation coils, setting algorithm of the robust feed-forward active shielding system of the magnetic field, as well as the resulting value of the induction magnetic field at the points of the protected space. New scientific results of the theoretical and field experimental researches of the effectiveness of a single circuit active shielding system with a single compensation coil are carried out. The possibility of reduction of the initial magnetic field induction level is obtained. It is shown that the experimental and calculated magnetic field induction values differ up to 20 %.

Aim. The synthesis of robust active shielding system of magnetic field, generated by group of high voltage power lines for reducing the induction of the initial magnetic field to the sanitary standards level and reducing the sensitivity of the system to variations in the plant parameters is given. Methodology. The synthesis is based on the solution of a multi-criteria stochastic game, in which the gain vector is calculated on the basis of the Maxwell equations solutions in the quasi-stationary approximation. The equilibrium state of the game is based on the stochastic multiagent optimization algorithms of the multiswarm particles. The initial parameters for the synthesis of active shielding system are the location of the high voltage power lines with respect to the protected from transmission line space, geometry and number of cables, operating currents, as well as the size of the protected space and normative value magnetic field induction, which should be achieved as a result of screening. The objective of the synthesis of the active shielding system is to determine their number, configuration, spatial arrangement, wiring diagrams and compensation cables currents, setting algorithm of the control systems as well as the resulting value of the induction magnetic field at the points of the protected space. Results. Robust active shielding system synthesis results for reduction of a magnetic field generated by group of high voltage power lines is given. The possibility of a significant reduction in the level of induction of the magnetic field source within and reducing the sensitivity of the system to variations in the plant parameters is given. Originality. For the first time carried out the synthesis of the robust active shielding systems of magnetic field generated by group of high voltage power lines within a given region of space. Practicalvalue. Practical recommendations on reasonable choice of the number and spatial arrangement of compensating cables of robust active shielding systems of the magnetic field generated by the group of high voltage power lines is given.

Purpose. Analyze the spatial and temporal distribution of the magnetic field of high voltage power lines with different design allowing and development of recommendations for the design of active screening systems by magnetic field of high voltage power lines. Methodology. Analysis of the spatial and temporal distribution of the magnetic field of high voltage power lines of different design allowing is made on the basis of Maxwell's equations solutions in the quasi-stationary approximation. Determination of the number, configuration, spatial arrangement and the compensation coil currents is formulated in the form of multiobjective optimization problem that is solved by multi-agent multiswarm stochastic optimization based on Pareto optimal solutions. Results of active screening system for the synthesis of various types of transmission lines with different numbers of windings controlled. The possibility of a significant reduction in the level of the flux density of the magnetic field source within a given region of space. Originality. For the first time an analysis of the spatial and temporal distribution of the magnetic field of power lines with different types and based on findings developed recommendations for the design of active screening system by magnetic field of high voltage power lines. Practical value. Practical recommendations on reasonable choice of the number and spatial arrangement of compensating windings of active screening system by magnetic field of high voltage power lines of different design allowing for the spatial and temporal distribution of the magnetic field. Results of active screening system synthesis of the magnetic field of industrial frequency generated by single-circuit 110 kV high voltage power lines with the supports have 330 - 1T «triangle» rotating magnetic field with full polarization in a residential five-storey building, located near the power lines. The system contains three compensating coil and reduces the level of induction of the magnetic field source to the sanitary standards of 0.5 µT in almost of all the house space.

In this paper, the effectiveness of lightning overvoltage protection of cables in high voltage overhead cable lines has been analyzed. Because of the high overvoltage level, the cables are protected by surge arresters and by metallic sheath earthing. However, in practice, quite a lot of cases of electricity-evoked damage to the cable outer sheaths are observed, proving that the effectiveness of the protection used is insufficient. As a result, the cables are exposed to environmental factors, especially moisture penetration, which contributes to cable degradation. To explain the causes of this situation, simulation studies were carried out to determine the relevant factors affecting the level of expected overvoltages. The circuit-field model of the overhead cable line in EMTP-ATP, COMSOL and MATLAB software was used for determining overvoltages on the main cable insulation and the outer protective sheath. The studies reveal that the efficiency of the cable insulation overvoltage protection is ensured regardless of the lightning strike location and the crest value of its current. However, the obtained results confirm that no matter the applied protection, the cable outer sheaths may be exposed to overvoltages with higher values than those of the main insulation. Although the analysis was performed for 110 kV lines, the conclusions are general and are also applicable to power lines with higher rated voltages.

Copyright of Electrical Engineering & Electromechanics is the property of National Technical University, Kharkiv Polytechnic Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

High-voltage overhead transmission lines on farmland imply a permanent easement. System operators should compensate for expropriation of land and depreciation of the remaining farm area, but recognize only the former. Therefore, landowners often appeal to the law courts for fairer refunds. This study highlights that the area occupied by plinths and cabins, the height of pylons and the type of intersection are the main sources of depreciation. Moreover, electric transmission lines depreciate the residual farm area, but involving only two narrow strips of land on either side of infrastructures. Finally, the depreciation tends to decrease rapidly as the distance from the transmission line increases. [ABSTRACT FROM AUTHOR]

Copyright of Electrical Engineering & Electromechanics is the property of National Technical University, Kharkiv Polytechnic Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Corona ions produced by high voltage power lines (HVPL) can alter the local atmospheric electrical environment downwind, potentially increasing electrostatic charge on airborne particulates via ion-aerosol attachment. However, previous epidemiological assessments attempting to assess this 'corona ion hypothesis' have used proxies e.g. ion concentration or distance from HVPL, rather than aerosol charge state directly, due to difficulties in modeling this quantity. We present a quasi-1D model incorporating both Gaussian plume dynamics and ion-aerosol and ion-ion interaction microphysics which could be applied to future studies of charged aerosol near HVPL. The response of the model to changes in a range of input parameters is characterized, and validation is attempted by means of comparison with previous work where ion- and aerosol concentrations and properties (including electrical mobility and electric charge states) upwind and downwind of HVPL are measured. [ABSTRACT FROM AUTHOR]

Corona ions from high voltage power lines (HVPL) can increase electrostatic charge on airborne pollutant particulates, possibly increasing received dose upon inhalation. To investigate the potential increased risk of childhood leukemia associated with residence near alternating current (AC) HVPL, we measured the particle charge state and atmospheric electricity parameters upwind, downwind and away from HVPL. Although we observed noticeable charge state alteration from background levels, most HVPL do not significantly increase charge magnitude. Particular HVPL types are shown to have most effect, increasing net charge to 15 times that at background. However, the magnitude of charge alteration during rainfall is comparable with the most extreme HVPL measurement. On current evidence, based on the current adult lung model, we suggest that although charge is sometimes enhanced to levels which may alter atmospheric particle dynamics, increased lung deposition is unlikely. [ABSTRACT FROM AUTHOR]

Copyright of Electrical Engineering & Electromechanics is the property of National Technical University, Kharkiv Polytechnic Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents the use of neuralnetworks in the study of electromagnetic interferencesbetween high voltage power lines and metallicunderground pipelines, for various constructivegeometries. Results gained with neural networks arecompared to the finite element solutions considered asstandard ones. Our contribution relates to theimplementation of the neural network AI technique, tothe study of electromagnetic interference problems andthe testing of the neural networks used in the studiedcase.

In recent years, the media impact of the damage from electromagnetic fields generated by high voltage power lines on human health has grown considerably. Hence, judges increasingly require the assessment of the compensation concerning the land depreciation for the ;''perception'' of the health risk from land market operators, regardless of the land use and the ascertainment of the health damage. The aim of this paper is the assessment of the ''perceptive'' devaluation of the Apulia agricultural lands in the presence of high voltage power lines and for different crop systems, in order to present a methodological approach that could support the experts appointed by judges. The analysis clearly shows that the perception of the risk of damage to human health is strongly felt by land market operators, causing an average devaluation of 33% and even up to 50% for greenhouses and farm buildings. [ABSTRACT FROM AUTHOR]

Copyright of Monatsschrift Kinderheilkunde is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Allium cepa bulbs were germinated in pots for three days on treatment area on which 380 kV high voltage power lines are passing. Ten bulbs were set up for each treatment area (0 m (meter), 10 m, 25 m, 50 m and 100+ m for control from power lines). Triticum baeoticum Boiss. subsp. baeoticum seeds were collected at same distance from power lines on planted field. Ten seeds from each area were germinated in Petri dishes for three days in laboratory. The treatment groups were compared with the control group for mitotic index and chromosome aberrations. Data obtained showed that electromagnetic fields from high voltage power lines increased the mitotic index and chromosome aberrations. [ABSTRACT FROM AUTHOR]

Investigations on exposure to electromagnetic have generated conflicting results both in epidemiological and laboratory studies, leaving their possible health consequences largely inconclusive. One of the well-reported reasons for the discrepancies is that there is no generally accepted theory to describe the interactions between the very weak electromagnetic fields and the living cells. This work presents a critical evaluation of three theories that describes the effects of weak electromagnetic fields on channel proteins in the cell membrane. The forced ion vibration model appears to explain the opening of ion channel proteins for exposures to low-frequency magnetic fields in the mili-Tesla range. No resonance frequencies or amplitude window effects are predicted in this method. We identify inconsistencies in the forced vibration model and show that the environmental magnetic fields that would be required to elicit opening of channel proteins are much stronger than predicted by the proposers of this model. The Ion Parametric Resonance model predicts a biological response at well-defined resonance frequencies for magnetic fields exceeding about 10 micro-Tesla. The oscillating magnetic field is assumed to act on proteins together with the earth's static magnetic field. This model predicts amplitude windows. We explain how a purely magnetic interaction, where in a two-stage ion magnetic resonance model, the conformation of a protein is changed under the influence of ions attached to its surface, which in turn, changes the function of the protein, can overcome the inherent signal-to-noise problem caused by electric thermal noise. The hydrogen nuclear polarization model predicts a biological response for oscillating magnetic field strengths above 0.1 micro-Tesla. The presence of a static magnetic field is required, and biological effects can be expected for frequencies below a few hundred hertz. All models except the forced vibration model can be applied for amplitude modulated microwaves. [ABSTRACT FROM AUTHOR]

Abstract: High voltage power lines produce corona ions which can create disturbances in the Earth''s vertical potential gradient. It has been hypothesised that these ions mediate adverse health effects such as the observed increase in leukaemia near to power lines. A fixed site monitoring station has been installed near two high voltage power lines which measures the vertical potential gradient throughout the year in all conditions. Ten minute samples of time varying potential gradient are sorted by wind direction to indicate whether the monitoring station is downwind of a power line and assessed for its variability by calculating mean, inter-quartile range and the number of turning points. Mean and inter-quartile range are related to wind direction, showing higher values when the wind is coming from the power lines. [Copyright &y& Elsevier]