Answer / santhosh

hysterisis losses and eddy current losses depends upon v/f
ratio hysteris loss=kB^1.6 f v if v/f ratio is constant
hysterisis loss is prportional to frequency i.e B is
constant if v/f is not constant hyloss is prop to f^-0.6 so
if freq is is increased hyloss is reduced but eddy current
loss remain constant because eddyis prop to B^2 f^2 so if we
sub v/f in the place of B eddy loss is prop to V^2 so it is
indepentent of frequency

Answer / ik3232

If the frequency applied to a transformer is increased, the
inductive reactance of the windings is increased, causing a
greater ac voltage drop across the windings and a lesser
voltage drop across the load. However, an increase in the
frequency applied to a transformer should not damage .

But, the applied frequency of the transformer is less than
the normal Frequency, the reactance of the windings is
decreased and the current through the transformer winding is
increased. If the decreasing frequency is enough, the
resulting increasing current will damage the transformer.

For this reason a transformer may be used at frequencies
above its normal operating frequency, but not below that
frequency.

Answer / dinesh b.e

The same current will flow for both 50 and 100Hz frequency.The Only difference is hysteresis losses will be more if 100Hz given as input. .Which only used to test the transformer's for 60second to check insulation withstand capability. .Generally hysteresis losses will be there in transformers which depends upon core quality. .Magnetising and Demagnetizing of core for 100cycles leads to increase in hysteresis loss.That is losses in form of heat .Which gives raise to increase the oil temperature.Due to this effect , chemical reaction Will take place between copper and sulfur content in oil.finally formation of copper sulphate,which acts as a conductor and settled upon windings . circulating current Will be there due to mmf.which leads to heat and damages the windings dielectric strength.

Answer / supriya saha

Iron loss increased.

Answer / shinde kv

when we applied double freq. that time eddy current losses
increase means iron losses will be increase hence increase
the heat loss.

Answer / daxity

Current is the RATE of flow of CHARGE in a circuit.
Frequency is the number of CYCLES per second......NOW..if
frequency is increased,the rate of flow of charge is
increased that is current,which may damage the insullation
on transformer winding due to over heating.

one cable insulation resistance 200 mega ohm. how find 250 meter cable resistance.

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