Answer / thowsif_emerson

One of the key concerns in the transmission of electricity
is the power loss in transmission lines, dissipated as heat
due to the resistance of the conductors.

High-voltage transmission lines are used to transmit
electric power over long distances. Normally, high voltage
(HV) transmission power lines are made of high voltage
(between 11 and 765 kilovolts) conducting lines of copper
and/or aluminum.

Assume the power to be transmitted is P, and the resistance
of the transmission line is r.
If the power is transmitted with voltage V, then the
current flow through the transmission line is I=P/V.

The power loss Ploss=I2*r=(P/V)2*r
Since P and r are fixed conditions, less power will be lost
if high voltages V are used.

Answer / nazeer

if voltage increase current decrease.in this way if we use
high voltage for transmission flow current can be reduced so
cable size and current loss can also be reduced.

Answer / sunil guru

As we move on to high voltages the current rating reduces(HV,EHV,UHV)AT ultra high voltages the current is very less (1150 kv and above)so the conductor size is less and thus the losses are less...... so high efficiency ........

R=(P*L)/A

FROM ABOVE EQ. IF AREA OF CONDUCTOR REDUCES SO RESISTANCE ALSO REDUCES AND AREA REDUCES ONLY IF CURRENT RATING IS REDUCED AND THAT IS POSSIBLE BY TRANSMITTING THE POWER AT HIGH VOLTAGES.

IF WE TRANSFER POWER AT SAY 230V THEN RECEIVING V WILL BE VERY LESS . REASON IS ALL POWER WILL BE DISSIPATED TO LOSSES..

FOR ANY DISAGREEMENT MAIL ME AT parmar20072008@yahoo.com

Answer / amarjeet sinha

230 V Supply is very low for transmission and this isn't
acceptable to transmission range. minimum value of
transmission of high tension line is 11Kv.

Answer / guest

Medium Voltage (11KV) is used for transmittion purpose
cause it reduce the size of cable. V=IR. The cable would be
large if 230V is used for transmittion since current would
be large. Basically, reduce the cost of transmission.

Answer / raja

Main pupuose is Core loss

Answer / dev

Min vol. for transmission is 33 kv not 11 kv
11 kv is max. distribution voltage

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