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INTRODUCTION:
The main function of any transmission system is transfer power from a place to
another place or from a network to another network..
Any transmission system consists terminal substations,transmission lines and
intermediate substations.
The increasing need of transmission of greater power led to continuous
increase in the transmission voltages.By the urge Extra High Voltage tran-
smission is introduced.
HISTORY:
In 1886 in Great Barrington, Massachusetts, a 1 kV alternating current (AC) distribution system was first installed.
The first transmission of three-phase alternating current using high voltage
took place in 1891 during the international electricity exhibition in Frankfut.
A 25 kV transmission line ,approximately 175 km long connected between… Lauffen on the Neckar and Frankfut.
In India after 1970 trend of using transmission voltages
higher than 300kv came(known as Extra High Voltage).....
Now Ultra High Voltage transmission(above 765kv) is….
used over long distances.…………………………..…………