Abstract: In this study, spatial differences of Power Transmission Line (PTL) and effects of the situation before and after the urban regeneration are studied by using Geographical Information System (GIS). In addition, a questionable and analyzable structure is acquired by developed system. In the study area many parcels on the PTL were analyzed. The amount of the parcels, which are affected by the negativity of PTL is clearly seen with the aid of generated maps. Some kind of changes are exhibited in the system, which are created by GIS, for instance before urban regeneration PTL was very close to people’s private properties and huge parts of PTL were among the buildings, however; after urban regeneration electricity lines were changed their locations to the underground. According to the results, GIS can be used as a device in planning and managing of PTL in urban regeneration projects and can be used for analyses. By the help of GIS technology, necessary investigations should be carried out in urban regeneration applications for creating sustainable cities.
Abstract: Various studies have showed that about 90% of single line to ground faults occurred on High voltage transmission lines have transient nature. This type of faults is cleared by temporary outage (by the single phase auto-reclosure). The interval between opening and reclosing of the faulted phase circuit breakers is named “Dead Time” that is varying about several hundred milliseconds. For adjustment of traditional single phase auto-reclosures that usually are not intelligent, it is necessary to calculate the dead time in the off-line condition precisely. If the dead time used in adjustment of single phase auto-reclosure is less than the real dead time, the reclosing of circuit breakers threats the power systems seriously. So in this paper a novel approach for precise calculation of dead time in power transmission lines based on the network equivalencing in time domain is presented. This approach has extremely higher precision in comparison with the traditional method based on Thevenin equivalent circuit. For comparison between the proposed approach in this paper and the traditional method, a comprehensive simulation by EMTP-ATP is performed on an extensive power network.
Abstract: This paper presents a wavelet transform and Support
Vector Machine (SVM) based algorithm for estimating fault location
on transmission lines. The Discrete wavelet transform (DWT) is used
for data pre-processing and this data are used for training and testing
SVM. Five types of mother wavelet are used for signal processing to
identify a suitable wavelet family that is more appropriate for use in
estimating fault location. The results demonstrated the ability of SVM
to generalize the situation from the provided patterns and to
accurately estimate the location of faults with varying fault resistance.
Abstract: The line sleeves on power transmission line connects
two conductors while the transmission line is constructing. However,
the line sleeves sometimes cause transmission line break down,
because the line sleeves are deteriorated and decayed by acid rain.
When the transmission line is broken, the economical loss is huge.
Therefore the line sleeves on power transmission lines should be
inspected periodically to prevent power failure. In this paper, Korea
Electric Power Research Institute reviewed several robots to inspect
line status and proposes a robot to inspect line sleeve by measuring
magnetic field on line sleeve. The developed inspection tool can
reliable to move along transmission line and overcome several
obstacles on transmission line. The developed system is also applied
on power transmission line and verified the efficiency of the robot.
Abstract: This paper describes a finite-difference time-domainFDTD) method to analyze lightning surge propagation in electric transmission lines. Numerical computation of solving the Telegraphist-s equations is determined and investigated its effectiveness. A source of lightning surge wave on power transmission lines is modeled by using Heidler-s surge model. The
proposed method was tested against medium-voltage power
transmission lines in comparison with the solution obtained by using
lattice diagram. As a result, the calculation showed that the method is one of accurate methods to analyze transient
lightning wave in power transmission lines.
Abstract: Since large power transformers are the most
expensive and strategically important components of any power
generator and transmission system, their reliability is crucially
important for the energy system operation. Also, Circuit breakers are
very important elements in the power transmission line so monitoring
the events gives a knowledgebase to determine time to the next
maintenance. This paper deals with the introduction of the
comparative method of the state estimation of transformers and
Circuit breakers using continuous monitoring of voltage, current.
This paper gives details a new method based on wavelet to apparatus
insulation monitoring. In this paper to insulation monitoring of
transformer, a new method based on wavelet transformation and
neutral point analysis is proposed. Using the EMTP tools, fault in
transformer winding and the detailed transformer winding model
were simulated. The current of neutral point of winding was analyzed
by wavelet transformation. It is shown that the neutral current of the
transformer winding has useful information about fault in insulation
of the transformer.
Abstract: High-voltage power transmission lines are the back
bone of electrical power utilities. The stability and continuous
monitoring of this critical infrastructure is pivotal. Nine-Sigma
representing Eskom Holding SOC limited, South Africa has a major
problem on proactive detection of fallen power lines and real time
sagging measurement together with slipping of such conductors. The
main objective of this research is to innovate RFID technology to
solve this challenge. Various options and technologies such as GPS,
PLC, image processing, MR sensors and etc., have been reviewed
and draw backs were made. The potential of RFID to give precision
measurement will be observed and presented. The future research
will look at magnetic and electrical interference as well as corona
effect on the technology.
Abstract: A power cable is widely used for power supply in
power distributing networks and power transmission lines. Due to
limitations in the production, delivery and setting up power cables,
they are produced and delivered in several separate lengths. Cable
itself, consists of two cable terminations and arbitrary number of
cable joints, depending on the cable route length. Electrical stress
control is needed to prevent a dielectric breakdown at the end of the
insulation shield in both the air and cable insulation. Reliability of
cable joint depends on its materials, design, installation and operating
environment. The paper describes design and performance results for
new modeled cable joints. Design concepts, based on numerical
calculations, must be correct. An Equivalent Electrodes
Method/Boundary Elements Method-hybrid approach that allows
electromagnetic field calculations in multilayer dielectric media,
including inhomogeneous regions, is presented.