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Categories >> Engineering >> Electrical Engineering
 


 

 
Question
Why Power generation in India is at 50Hz while in America
its 60Hz so is there any advantage/Disadvantage of this ??
 Question Submitted By :: Electrical Engineering
  I also faced this Question!!      
Answer Posted By  
 Answers were Sorted based on User's Feedback
Answer
# 1
in US the frequency is 60hz and 110v supply. but in india
is about 240v,50hz supply. for a particular load say 100kw
the current will be 0.416A. but in US the same load will
consume about 0.9A. here the thing is the heat produced in
the cable bcoz of the flow of current will be large in US
compare to india. since US is a cold country they can use
this level but not by india. 

Is This Answer Correct ?    144 Yes 40 No
mullu
 
Answer
# 2
During the development of commercial electric power systems
in the late 19th and early 20th centuries, many different
frequencies (and voltages) had been used. Large investment
in equipment at one frequency made standardization a slow
process. However, as of the turn of the 21st century,
places that now use the 50 Hz frequency tend to use 220-240
V, and those that now use 60 Hz tend to use 100-120 V. Both
frequencies co-exist today (some countries such as Japan
use both) with no technical reason to prefer one over the
other and no apparent desire for complete world-wide
standardization.

Unless specified by the manufacturer to operate on both 50
and 60 Hz, appliances may not operate efficiently or even
safely if used on anything other than the intended
frequency. 

Is This Answer Correct ?    33 Yes 14 No
sarfraz
 
 
Answer
# 3
Mr 'Tripple X'. if u know the answer then u post it.It was
my opinion I have told to that question.if u have that much
of guts then u also post some unique answer.

BETTER TAKE CARE OF UR WORDS

u tell me where do u not find the backwardness in our
country......if u roam in atleast in one lane of India, u
will find many food less people...if u think that India is
such a forward country then there must not be any such kind
of hungry deaths or unemployment deaths. If India is such a
forward country then each and every person must be having
food 3times a day......
if u have that much guts bring back the money in swiss bank
accounts and give it to citizens.....so that they may live
happily from now onwards atleast....

aap ki desh prem ko main salaam kartha hoon lekin sachhayi
toh yahi hain naa.....shayad aap ki city main aur town main
aisa nahi ho lekin 70-80 % bharat log ko khana nahi mil raha
hai....

insaan ko ek baar main samaj mein aajaataah hai......main
expect kar raha hon ki aap ko samaj main aa gaya......

thank u....for giving me a chance to speak the burden in my
heart......and gud byee..... 

Is This Answer Correct ?    17 Yes 6 No
thuranga
 
Answer
# 4
The reasons for power supply frequency in India to be 50 Hz
and in US to be 60 HZ are:
1.ENVIRONMENTAL FACTORS :::::The average annual temperature
of India is greater than US
2.POWER GENERATION REASONS :To generate power of that
frequency it costs alot and the size of the alternator is
huge and it costs an incredible amount which we cant afford
3.EDDY CURRENT LOSSES :As frequency increases eddy current
and hysteriss losses increasesand hence power loss also
increases. 

Is This Answer Correct ?    13 Yes 6 No
hitesh pulluru
 
Answer
# 5
Early in the history or electricity, Thomas Edison's
General Electric
company was distributing DC electricity at 110 volts in the
United States.
Then Nikola Tesla the devised a system of three-phase AC
electricity at
240 volts. Three-phase meant that three alternating
currents slightly out
of phase were combined in order to even out the great
variations in
voltage occurring in AC electricity. He had calculated that
60 cycles per
second or 60Hz was the most effective frequency. Tesla
later compromised
to reduce the voltage to 110 volts for safety reasons.

Europe goes to 50Hz:
With the backing of the Westinghouse Company, Tesla's AC
system became the
standard in the United States. Meanwhile, the German
company AEG started
generating electricity and became a virtual monopoly in
Europe. They
decided to use 50Hz instead of 60Hz to better fit their
metric standards,
but they kept the voltage at 110V.

Unfortunately,
50Hz AC has greater losses and is not as efficient as 60HZ.
Due to the slower speed 50Hz electrical generators are 20%
less effective
than 60Hz generators. Electrical transmission at 50Hz is
about 10-15% less
efficient. 50Hz transformers require larger windings and
50Hz electric
motors are less efficient than those meant to run at 60Hz.
They are more
costly to make to handle the electrical losses and the
extra heat
generated at the lower frequency.

Europe goes to 220V
Europe stayed at 110V AC until the 1950s, just after World
War II. They
then switched over to 220V for better efficiency in
electrical
transmission. Great Britain not only switched to 220V, but
they also
changed from 60Hz to 50Hz to follow the European lead.
Since many people
did not yet have electrical appliances in Europe after the
war, the
change-over was not that expensive for them.

U.S. stays at 110V, 60Hz
The United States also considered converting to 220V for
home use but felt
it would be too costly, due to all the 110V electrical
appliances people
had. A compromise was made in the U.S. in that 220V would
come into the
house where it would be split to 110V to power most
appliances. Certain
household appliances such as the electric stove and
electric clothes dryer
would be powered at 220V.

My opinion on this is that even though high frequency can
save your cost in manufacture, but it also cause
significant loss in power transmission
especially for large scale power systems. So we need trade-
off.

In the debate 50 - 60 Hz, Prof Trevor Blackburn treated the
subject very well in the case of
transformers, cf below reference, appendix I.2. There are
several loss components that actually
increase with higher frequency (some even increase
proportional to the square of the frequency),
such as hysteresis loss, eddy current loss, losses caused
by harmonics and skin effect.
Higher frequencies would limit the size of transmission
lines and power
transmitted on high voltage transmission systems.





@Thuranga: Indian economy will surpass the US economy by
2050. 

Is This Answer Correct ?    12 Yes 5 No
mohit yadav
 
Answer
# 6
Well what i feel is that their is no particular reason for
US using 60 hz and we going for 50 hz. But the ratio V/f is
what really matters i.e. any m/c made to operate at a
particular v/f ratio will either be under rated or under
utilized if the ratio goes less and vice versa. With
increased freq., freq losses also increases and so eff.
goes low and o/p is reduced. 

Is This Answer Correct ?    10 Yes 5 No
gautam himmatramka
 
Answer
# 7
what may be the country ,if we increase the frequency load
requirement is less for example if we normally use 50Hz 220v
supply .now frequency is dropped to 49HZ then load
requirement is higher than 220v.so increase the frequency is
the way to tame the load requirement(refer cl.wadwha) 

Is This Answer Correct ?    9 Yes 6 No
prabveen patel
 
Answer
# 8
hey guys I found another answer for it......

if we consider the temperature parameters of the
America....then it is almost cool all through the
year,excepting 2 to 3 months maximum.

we all know that in conductors, heating the conductors will
lower its resistance,similarly,cooling also increases the
resistance.
so for preventing the losses, the driving current must be
high, but to maintain the power constant the voltage is
reduced to 110V. So to make the current high,frequency will
be high,and they found that losses were low on operation of
equipment at 60Hz than at 50Hz.

but when u take tropical places almost the whole operation
is with 50Hz.

but here arises another question that,equator passes through
America also,but even then they use 60Hz for their operation.?
My answer is, there will be no different power generations
with different ratings of voltage and frequencies,as all the
states are interconnected just similar to other countries to
meet the demand of power.
so for small number of states the whole country is not going
to change the operation of frequency. 

Is This Answer Correct ?    20 Yes 17 No
thuranga
 
Answer
# 9
in US the frequency is 60hz and 110v supply. but in india
is about 240v,50hz supply. for a particular load say 100kw
the current will be 0.416A. but in US the same load will
consume about 0.9A. here the thing is the heat produced in
the cable bcoz of the flow of current will be large in US
compare to india. since US is a cold country they can use
this level but not by india. 

Is This Answer Correct ?    10 Yes 8 No
hitesh
 
Answer
# 10
we all know that the power generation in India is at 220v at frequency 50hz but in America it is 110v at frequency 60hz,the main reason behind this is that the impedance of inductor increases with frequency and that of capacitor decreases.if we find over all impedance of the combination of inductor,capacitor and resister we can see that the current supply would increase with a little decrease of frequency.the formula for current calculation is given as..
i= v/(r^2+(wL-1/wC)^2).
where,
w=2*pi*f. 

Is This Answer Correct ?    2 Yes 1 No
shah alam
 

 
 
 
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