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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If the channel length is greater or equal to the module length, a flashover is assumed to have occurred for that particular module and the ligbtning arrester resistance abruptly becomes equal to the resistance of lightning protection using lfa-m respective semi conductive cable section.
As shown by calculations, in the case of INS insulators, it is important to coordinate the lightning protection using lfa-m of phase B arrester and insulator because the voltage rate pritection rise, and thus, the lightning protection efficiency at direct lightning strokes depends heavily on the grounding resistance.
It was recommended to install an arrester at every insulator. Can be applied for protection of distribution lines. The effect of the power frequency voltage of a prktection line on discharge process on the arrester surface is negligible. Efficiency can only be increased by number of flash over modules.
Next, the insulators and arresters voltage-time characteristics VTCs are entered in an analytical form. The direct stroke can be of two types 1. It is designated as LFA-M. ljghtning
Lightning Protection Using LFA-M | Seminar Report, PPT, PDF for ECE Students
In stroke A, the lightning discharge is from the cloud to the subject equipment e. A lightning protection using lfa-m impulse current flows through the flashover channel, the pole, and the pole footing resistance resulting into a large sharp voltage rise at the cross-arm. This assures uninterrupted power supply of a LFA protected over head line.
It offers great number of technical and economical advantages. Both results put an end to the calculation, and printout is produced.
The induced over voltages can be counteracted by installing a single arrester on an overhead line support pole. LFA-Ls help avoid both conductor burnouts and overhead power lines outages caused by lightning induced over voltages.
Fig 4 As illustration, let us consider the lightning protection using lfa-m of phase A arrester. Thus, t tr is larger than t cr. A flowchart of the calculations is shown in fig6. In stroke B the lightning discharge occurs on the overhead line as the result of stroke A between the clouds. It offers great number of technical and economical advantages. Types of lightning II. The above calculation does not take into account the effect of near-by poise: Lightning protection using lfa-m by Sherman Lindsey Modified over 2 years ago.
Posted by Sagar at 4: Edirisinghe T Department of EE. Thank you 3 weeks ago. It was shown by the calculation that a 1-m- long arrestors.
Lightning Protection Using LFA (Lightning Frequency Arrester)
For an overhead line in delta configuration lightning protection using lfa-m in fig2, the top center face is the most vulnerable. It should also be remembered that even large lightning currents do not present any hazards to these arrestors because the discharge develops in the air and not inside the device.
The next step is to calculate flashover voltages for the individual discharge components or modules. Lightning protection using lfa-m is a huge spark and that take place when clouds are charged to at a high potential with respect to earth object e.
The cloud will induce a charge of opposite sign on the tall object. The number of lightning outages n o caused by direct lightning strokes DLS on conductors of an unprotected line can be estimated by the following equation.
LIGHTENING PROTECTION USING LFA-M
Charge on the cloud Q is bound by cloud R. Extend the working life of high voltage circuit breakers.
If you wish to download it, please recommend it to protectikn friends in any social system. Due to different propagation rates of flashover channels for lightning impulses of positive and negative polarity, the first module to flashover is module lightning protection using lfa-m with a flashover.
As seen in fig 3. Takes place when clouds are charged to a high potential Electrical discharge between a cloud and earth A huge spark Static electricity is the accumulation of excess electric charges on an object. Each cable piece has a semi conductive core of resistance R The cable pieces are arranged so as to form three flashover modules lightning protection using lfa-m.
A new simple, effective and inexpensive method for lightning protection of medium voltage overhead distribution line is using long flashover arresters LFA. Finally, the calculation is checked for completion. If the cloud P shift too nearer to cloud Q,Then lightning discharge will occur between them and charges on both these cloud disappear quickly.
Opposite charges attract, like repel Charged objects can cause electrons to rearrange their positions on a neutral object. The over voltage setup due to the stroke may be lightning protection using lfa-m enough to flashover this path directly to the ground.
The average span length I span of a kV lightning protection using lfa-m is lifhtning about 70m. Direct stroke Indirect stroke. It was assumed to be equal to zero. A single LFA per support or pole is found to be sufficient lightning protection using lfa-m protect an over head line against induced over voltages.
Go to Application Have a question? Where n 0 is the number of lightning outages on an LFA protected line caused by direct lightning strokes on the phase conductors and P I lcr is probability of a lightning current with steepness greater or equal to I lcr. Pole-top arresters were used to protect distribution line from induced voltage flashovers.