Answer / shirish

1.generation efficency increased
2.less copper conductor is used for 3 phase power generation
as compared to 1 phase power generation.
3.more efficiency of eqvipment as compared to 1 phase

Answer / gunasekaran

power loss will more in single phase than 3 phase for
example we have to transmit 100A current for single phase
system .
2*Isqr*R= 2*10000*R=20000Rwatts
for 3 phase system 3*Isqr*R=3*57.7sqr*R=10000R watts power
has dissipated so 3 phase system better than 1phase

Answer / pradeebha

1.in case a fault occurs in a line ,unlike single phase the
continuity of power supply will not be affected i.e the
other two lines of 3 phase will not get affected.
2.single phase loads can also be operated by connecting it
between line and neutral.

Answer / paul

I do not think the previous answer is correct. Three phase is more efficient (Power In v Power Out) in respect to AC motors, and is also more cost economical in regards to power transmission as less copper is required for the same delivered power (given the 3 phase line voltage is taken as being he same as the equivalent single phase voltage therefore allowing the use of cable with the same voltage rating), however..

The transmission power loss (and therefor transmission efficiency) in a three phase systems is the same as in a single phase system (again, assuming same total load power and line voltage).

The previous response has omitted the fact that, even though there is no neutral wire the return current in a three phase system will be subject to I^2*R losses in the associated conductors. Taking R as the loop resistance (supply and return), a single phase system power loss can be calculated as I^2*R. For a balanced three phase system, the single phase equivalent losses will be ((I/root3)^2)*R. Therefore total losses = 3*((I/root3)^2)*R = I^2*R.

Answer / bala

l.power generation is 3 phase. so power transmission also
in 3 phase.
2.Quantity of power transmission also consider in case of 3
phase we can transmit more power than conpare to single
phase.

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