dampers used in electrical transmission lines

DAMPERSSubmitted To:

Sir, Muhammad Shafiq Ahmad

PRESENTED BY:Rana Adeel BSET-01113066Shafiq-ur-Rehman BSET-01113035

DAMPING SYSTEMS

Due to wind, overhead transmission lines will be excited to vibrations and oscillations that can lead to damage on the conductor of the overhead transmission line, single parts or the pole. In order to reduce these vibrations and oscillations to an uncritical dimension, damping systems will have to be installed in the overhead transmission lines.

VIBRATION DAMPER IN TRANSMISSION LINE

Wind-induced vibration of overhead conductors is common worldwide and can cause conductor fatigue Near a hardware attachment.

EFFECT OF VIBRATION:

It should be understood that the existence of vibration on a transmission or distribution line doesn’t necessarily constitute a problem. However, if the magnitude of the vibration is high, damage in the form of abrasion or fatigue failures will generally occur over a period of time.

FEATURES:

Clampweights WireBolt

TYPES OF DAMPERS

1. Stockbridge Damper2. ELGRA dampers3. Tersional dampers4. Haro damper5. Twin Spacer Damper 6. Triple spacer Damper 7. Quadruple Spacer Damper 

STOCKBRIDGE DAMPER

These dampers are used to counteract vibrations excited by

wind, Depending on the type of the the conductor of theOverhead transmission line, several damper types with

manyDifferent models are available. The name of the damper

isdue to the scientist H. Stockbridge, who advanced thedevelopment of the damper in the 1920’s. The functionalmode has not changed up to now and is one of the

methodsfor reducing vibrations on overhead transmission lines

thatare spread most.

ELGRA DAMPERS

ELGRA dampers from Sweden were installed on the first 330kV lines emanating from the Snowy River. These consisted of a number of weights resting on elastomer pads around a central rod suspended vertically.

TORSIONAL DAMPERS

Torsional Damper is the most modern anti-galloping device available today which has been specially designed for use on bundled high voltage and extra high voltage (132kv and up to more) power transmission lines.

HARO DAMPER

The Haro damper, although expensive, virtually solved the

vibration problems at Saskatchewan Power. Its one disadvantage

was that it was over a meter in length and was difficult to

transport and install.

SPACER DAMPERS

Spacers serve to establish a distance between the partialconductors of a bundle line in order to prevent the

conductors from knocking together and thus avoid damage done toconductors. Spacer dampers will be used if vibrations

excited bywind need to be expected. the vibration amplitudes of the

conductorcan be reduced to an uncritical dimension. In this context,

manydifferent models of the spacers are available for different

bundlearrangements.

TWIN SPACER

Twin Spacer - Dampers are used to control vibration and conductor oscillation, maintain conductor spacing and restore conductor spacing after a short circuit occurs.

Material: Frame, arm and keeperAluminium alloyNut and bolt

TRIPLE SPACER DAMPER

Spacer dampers were originally developed to suppress bundle conductor sub span oscillations that could cause damage to multi-conductor bundle systems.

Spacer Dampers are designed to provide corona free performance on operating voltages up and including 500 kV. Special designs are available for 765 kV applications.

QUADRUPLE SPACER DAMPER

Spacer-damper installed on a square four conductor bundle to control both vibration and wake induced oscillation.

REPLACEMENT AND INSTALLED