Explore Lightning Protection Using LFA-M with Free Download of Seminar Report and PPT in PDF and DOC Format. Also Explore the Seminar Topics Paper on. The important feature of this modular long flashover arrester (LFA-M) is that it can be applied for lightning protection of overhead distribution line against both. Presentation on theme: “LIGHTENING PROTECTION USING LFA-M”— System ”-A system of lightning protection conductors lightning rods -installed on the.
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Thus, the number of outages caused by direct lightning strokes can be lowered with portection use of LFA arresters by an order of magnitude or more even for high values of grounding resistance. It is seen from Fig. Induced over voltages can lightning protection using lfa-m counteracted by installing a single arrestor on an overhead line support. The next step is to calculate flashover voltages for the individual discharge components or modules.
Automatically changes to Flash or non-Flash embed. The induced over voltages can be counteracted by installing a single arrester on an lightning protection using lfa-m line support pole.
LIGHTENING PROTECTION USING LFA-M
The above calculation does not take into account the effect of near-by poise: With one or both outer phase arresters activated, a two or three phase lightning flashover is kightning. An LFA-M lightning protection using lfa-m consists of two cables like pieces.
Aim is lfa-n reduce the number of air terminals required by a lightning protection using lfa-m Franklin-type system. On the other hand, the potential of the adjacent phases also increases due to electromagnetic coupling between conductors but at much slower rate than that applied to the top phase insulator consequently, an outer phase arrester operates under much easier coordination conditions than a top phase arrester.
Electricity The movement of charge from one place to another Requires energy to move the charge Also requires conductors. About project SlidePlayer Terms of Service. Where k is the outage reduction factor of lightning outages caused by direct lightning protection using lfa-m strokes.
A heavy impulse current flows through the flashover channel, the pole, and the pole lightning protection using lfa-m resistance resulting into a large sharp voltage rise at the cross-arm. For the protection of lines against direct lightning strokes, the arresters are connected between the poles and all of the phase lightning protection using lfa-m in parallel with the insulators.
Each cable piece has a semi conductive core of resistance R. You do not have the permission to view this presentation. When the potential between the cloud and line exceed the breakdown value of air, the lightning discharge occurs between the cloud and the line.
Lightning Protection Using LFA (Lightning Frequency Arrester)
Before flash over, the total resistance of the arrester can be assumed to be infinitely large. Extend the working life of high voltage circuit breakers. As seen in fig 3. Lightning protection using lfa-m assures uninterrupted power supply of a LFA protected over head line.
When the potential between the cloud and line exceed the breakdown value of air, the lightning discharge occurs between the cloud lightning protection using lfa-m the line. Systems that provide an increased zone of protection Systems that eliminate lightning strikes altogether.
Types of Lightening Strokes Types of lightning II. It protectuon great number of technical and economical advantages. The important feature of this modular long flashover arrester LFA-M is that it can be applied for lightning protection of overhead distribution line against both induced overvoltages and direct lightning strokes. The result is that negative lightning protection using lfa-m rushes along the line is both directions in the form of traveling wave.
The cable pieces are arranged lf-m as to form three flashover modules 1,2,3 as shown in figure1.
After the LFA A fully flashed over, the lightning current travels through the pole and its footing. Lightning is an electrical discharge between cloud and the earth, between clouds or between the fla-m centers of the same cloud.
Therefore, the nearest pole is not to be taken into account in the coordination analysis of the LFA A. A long flashover arrester LFAwhich comprises of three flashover modules using the creeping discharge effect, is lightning protection using lfa-m in this paper.
Thus the total voltage is applied to each flashover module at the same moment, and all the three flashover modules 1, 2 and 3 are assured conditions for simultaneous initiation of creeping discharges lightning protection using lfa-m respective modules flashed over, develop a single long flashover channel PowerPoint Presentation: Protection against Lightning Overvoltages Overvoltages due to lightning strokes can be avoided or minimized in practice by d shielding the overhead lines.
Seminar for you: Lighting protection using LFA-M
The cable pieces are arranged so as to form three flashover modules 1,2,3 uing shown in figure1. From the line, current path may be over the insulators down to the pole to the ground. Provides a low-impedance path for the lightning lightning protection using lfa-m to lessen the heating effect. The flashover length, L is oightning for lines with wooden structures rather than lightning protection using lfa-m or concrete structures, because wooden Cross-arm increases the flashover path.
In stroke B the lightning discharge occurs on the overhead line as the result of stroke A between the clouds. The rate of decrease of the critical gradient slows down for larger fault currents.
The over voltage setup due to the stroke may be large enough to flashover this path directly to the ground. Edirisinghe T Department la-m EE.
Therefore, this new lightning protection system is thought to feature simple design, low lightning protection using lfa-m, and high reliability.
Charge on the cloud Q is bound by cloud R. The calculation is carried out for a linear increase of the lightning protection using lfa-m current, that is. Each cable piece lightning protection using lfa-m a semi conductive core of resistance R The cable pieces are arranged lf-am as to form three flashover modules 1,2,3.
A new simple, effective and inexpensive method for lightning protection of medium voltage overhead distribution line is using long flashover arresters LFA. It offers great number of technical and economical advantages. The voltage-time characteristics of this modular arrestor assure reliable protection of medium voltage overhead lines against both induced over voltages and direct lfaa-m strokes. Thus, the insulators of the healthy phases are stressed and flashed over by lightning protection using lfa-m voltage equal to the potential difference between the cross arm and the phase conductor.
Lightning is a huge spark and that take protecton when clouds are charged to at a high potential with respect to earth object e. Direct stroke Indirect stroke. In direct stroke, the lightning discharge is directly from the cloud to the an overhead line.
Indirect stroke result from eletrostatically induced charges on the conductors due to the presence of charged lighyning.