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Question
why we step up voltage for reducing the loss, even if
voltage and current are proportional anr resistance remains
same
Question Submitted By :: Anupamdavv
I also faced this Question!!     Rank Answer Posted By

Re: why we step up voltage for reducing the loss, even if voltage and current are proportional anr resistance remains same
# 1
In this case ,we should not consider ohm's law... Generally
we step up voltage at the time of transmission right?? we
do this because it makes us to transmit power at high
voltage and low currents...and more over transmission
losses are calculated as copper losses=(I*I)R losses ..so
at low currents low transmission losses...Hope U
understand..

 Is This Answer Correct ? 31 Yes 6 No
Kaarthik

Re: why we step up voltage for reducing the loss, even if voltage and current are proportional anr resistance remains same
# 2
p=vi,since p is constant and if we increase "v" then "i"
will decrease i.e. loss will decrease.

 Is This Answer Correct ? 10 Yes 3 No
Rabindra

Re: why we step up voltage for reducing the loss, even if voltage and current are proportional anr resistance remains same
# 3
Rabindra for power loss we never use p=vi formula and the
logic u have given doesn't make any sense
power loss=i^2*r
that is why we step up voltage to reduce current.
While transmission we take care of current and in
distribution to consumer voltage is taken care of

 Is This Answer Correct ? 10 Yes 1 No
Shekhar

Re: why we step up voltage for reducing the loss, even if voltage and current are proportional anr resistance remains same
# 4
when we step up the voltage ,then current flowing in that
circuit will reduce. losses are directly proportional to
current.
cu. loss= i*i*r
so if we step up the voltage, then we can reduce the losses

 Is This Answer Correct ? 10 Yes 0 No
Naveen

Re: why we step up voltage for reducing the loss, even if voltage and current are proportional anr resistance remains same
# 5
For transmission we are step up the voltage, Not only
reducing the copper loss but there are many factor to step
up the voltage
1) Transmission line conductor is calculated behalf of
current capacity.To transmit high current we have to
provide big diameter lines.Which is costly, Tower cost
increase.
2) current less means conductor diameter size will
less.Conductor cost will be less.
3) Obiviously the copper loss is dependent upon current,
Current less, It will help to reduce the copper loss.

So main factor to step up voltage is, to reduce cost of
material.To make the rigid the system.Easy for maintenance.

 Is This Answer Correct ? 26 Yes 0 No
Abdurrahim

Re: why we step up voltage for reducing the loss, even if voltage and current are proportional anr resistance remains same
# 6

in my point view
for high current and low voltage transmission
1.AC current flow outermost conducter in grid bus,so
loss of skin effect more is one the factor
2.Current carring capacity is high,so it is need spical
type bushing and transmission tower,in bteween lines need
more support.it is diffecult maintance

 Is This Answer Correct ? 4 Yes 4 No
Gtmanikandan

Re: why we step up voltage for reducing the loss, even if voltage and current are proportional anr resistance remains same
# 7
For transmission we are step up the voltage, Not only
reducing the losses but there are many reason to step
up the voltage
1) Transmission line conductor is calculated behalf of
current capacity.To transmit high current we have to
provide big diameter cable/line, and big diameter line
cable weight is more.Which is costly, Tower cost
increase.
2) current less means conductor diameter size will
less.Conductor cost will be less.
3) Obiviously the copper loss is dependent upon current,
Current less, It will help to reduce the copper loss.

So main reason to step up voltage is, to reduce cost of
material.To make the rigid the system.Easy for maintenance.

Exm.:- In generation station first we generate 11 kv, and
after generation we provide stape up transformer.

 Is This Answer Correct ? 6 Yes 1 No
Pranav Pathak

Re: why we step up voltage for reducing the loss, even if voltage and current are proportional anr resistance remains same
# 8
In the transmission line we have more losses due to the flowing of current bcz when the current is flowing from conductor it faces the skin effect ..so due to that reason we have to decrees flow of current in T/L.... for that we need
to increase voltage....
AND...
In other words...
cu loss=i*i*r..
so due to above equation losses are directly prop to square of
current so if flow of current will decrease than losses will
decrease

 Is This Answer Correct ? 0 Yes 0 No
Pavan Kumar.m

Re: why we step up voltage for reducing the loss, even if voltage and current are proportional anr resistance remains same
# 9
In a Transmission line we used Step-up voltage for transmit
the power, there are so many reasons for use of high
voltage, some is as follow:-
1) The resistance loss is I*I*R. By the formula if current
is low them resistance loss will low and line efficiency
will increase.
2) For a low current value, we should use a conductor with a
low cross section area for same power, as such cost of the
conductor & weight of conductor will also reduce.
3) As the weight of conductor will reduce, the weight of
Tower structures for carrying the low weight conductor will
also reduce and the cost of tower / project will reduce. As
such the capital cost of line also reduce.
4) As the tower weight is reduce, the foundation volume for
tower is also reduce. As such the capital cost of line is
reduce.

On the consideration of the above losses and the reduction
of capital cost of project. We will use a high voltage
system to transmit the power.

Regards.
Vishal kr. Sharma.
(Simplex Infra. ltd.)

 Is This Answer Correct ? 1 Yes 1 No
Vishal Kumar Sharma.

Re: why we step up voltage for reducing the loss, even if voltage and current are proportional anr resistance remains same
# 10
Voltage is proportional to Current as we consider Ohms Low.But in the case of Transformer how the current reduce while stepping up voltage.all right it is for reducing loss and make transmission is cost effective..

But why the current is reducing and which formula or theory can explain the exact reason about this question.?

let me know from anyone??

 Is This Answer Correct ? 0 Yes 0 No
Abdul

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