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What are the criteria for the classification of transmission lines as short, medium and long lines?

What are the criteria for the classification of transmission lines as short, medium and long lines?

Answers

gregory
The network of transmission lines is formed by three phase AC system. This is required
for Bulk power transfer from large group of generating stations to main transmission
network.
Short power transmission line:
Short distance power transmission lines has voltage £ 11000 volts. These lines are
required to carry power from main sub-station to local distribution area. Further power
supply is distributed through pole mounted sub- station or plinth mounted sub-station.
Medium power transmission line:
Medium distance power transmission line has voltage range 33-132 kV. For the economic
voltages for medium lines an approximate rule is 1 kV/mile or 0.6 kV/km. kV= 5.5 km x
0.6 + kW/100. These lines supply power directly to big organization or industry, which
establishes own sub-station.
Long power transmission line
A long distance power transmission line has voltage range 220 kV to 750 kV. These lines
are used for transfer of power from sending end to receiving end or for system interconnection
for exchange of power between independently controlled networks. For longer
transmission lines, higher power transmission voltages are necessary (p  v2). Higher
voltage gives lesser current, lesser I2R losses, higher power transferability.
gregorymasila answered the question on February 22, 2018 at 16:29

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