Answer / neeladree chakravorty

Yes we can .
In fact if we use higher frequency then according to the emf
relation of E=4.44fBAN,
we can see that for a given rated voltage, the Area of cross
section of the transformer core will reduce.
So the Volume of the transformer will be reduced and hence
it will be lighter and lower will be the material cost.

Answer / nagarjuna

i cant understand u r answer NEELADREE.WIL U TEL ME CAN WE USE R NOT,IF S HOW.IF NO Y.

Answer / neeladree

Nagarjuna,
I had mentioned my answer in the first line. "Yes we can".
the reason is clearly mentioned.
But mind it, that the transformer is designed for 70 Hz
operation and we are operating it at 70 Hz.

Answer / nithi

yes. we can use the transformer for 70 Hz with same voltage
rating.

Reason: For the same voltage rating if we increase the
frequency,the flux carried by the core material will be
reduced .Thereby the hysteresis loss is reduced which
results, reduced iron loss.

Answer / kc

a transformer can be operated at 70 hz but the kva and emf rating increases; also the lines connected to it should be capable of changing the freq at its entry and exit pts to synchronise with the line freq of 50 hz in india and 60 hz in the usa.also with higher freq the area of cross section of laminations decr which makes it diff and costly to manufacture.

Answer / arun

YES WE CAN IN FACT ON HIGHER FREQUENCY THE LOSSES WILL DECREASES AS Ph=Kh *f*Bmax1.6* (hystereis loss )
Pe=Ke*f2*Bmax2(eddy current loss)
V=4.44*f*Bmax*N
so if i put the value of Bmax from the third equetion then eddy curren loss will be independent of the frequency but hysterysis loss is inverly propotional to B(power .6 )
so from here its clear that if frequencuy increase then losses decreases so

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