the efficiency of transformer is more than alternator, because 1- the alternator have friction and windage loss but in transformer this not occure. 2- in the alternator the flux leak is more than the transformer, because in case of alternator the flux move through the air which is dimagnet and in transformer flux move through silicon steel. 3- in the other hand alternator have dc compound generator for exciation (depend on other electric course 220volt) but in t/f is not need.
The flux density is set at the most the core material can stand, which for standard laminated transformer iron is around 1 Weber per square metre. Based on that and the cross-section area of the core, the volts per turn figure is calculated for both the primary and the secondary winding. If the operating voltage stays constant, so will the flux density and the iron losses.
The phase shift is caused by inductance in the transformer. Any inductance from magnetic flux that fails to link both windings is called leakage flux, and the resulting inductance is called leakage inductance.
The changing magnetic flux in the iron core of the transformer induces a voltage in the windings.
A generator, in general.
when a load is connected to a transformer current(say I2) flows through secondary coil thus an M.M.F (N2I2) is produced ,this produces the secondary flux. This flux reduces the the main flux induced in the primary & also reduces E.M.F E1 in the primary As a result more current is drawn from the supply. This additional current drawn is due to the load component(say I2' ) This I2' is anti-phase with I2.This I2' sets a flux which opposes the secondary flux & helps the main flux. The load component flux neutralises the secondary flux produced by I2 .The M.M.F N1I2' balances N2I2.Thus the net flux is always at constant level. As practically flux is constant,the core loss is constant for all loads. Hence a transformer is always called a Constant Flux Machine.
when a load is connected to a transformer current(say I2) flows through secondary coil thus an M.M.F (N2I2) is produced ,this produces the secondary flux.This flux reduces the the main flux induced in the primary & also reduces E.M.F E1 in the primaryAs a result more current is drawn from the supply. This additional current drawn is due to the load component(say I2' )This I2' is anti-phase with I2.This I2' sets a flux which opposes the secondary flux & helps the main flux.The load component flux neutralises the secondary flux produced by I2 .The M.M.F N1I2' balances N2I2.Thus the net flux is always at constant level.As practically flux is constant,the core loss is constant for all loads.Hence a transformer is always called a Constant Flux Machine.
The flux is set by the voltage applied to the transformer. In most applications, the voltage is constant, and therefore the flux is constant also.
transformer cannot be worked on DC because as the dc is constant there will be no change of flux & may lead to shot circuit.
According to Faraday's Law only if there is change in flux linkage of a conductor then current is induced between mutual inductors. Now DC will induce a constant a constant flux in the transformer core, consequently in the secondary coil. So constant flux cannot induce a current in the secondary. SUBHRA JYOTI SAHA
No.it is not possible.as transformes action based upon induction principle it requirs varying flux.for dc the flux is constant.
In a 3-ph transformer the flux also rotates round the 3 cores but you don't see anything moving.
since the volt amphere turns in secondary neautralises the primary voltamphere turns making the magnetic flux in the core remain constant
In transformers, it is the no.of turns of winding which is constant is use to merely step up or down voltage or current. The magnetic flux is linked with the coils due to current flowing through the coil and nothing more.Hence Transformer is a passive device.
Transformer works with varying flux. DC won't create it. Only AC produce varying flux.
dc flux is caused by dc current (flux and current are proportional), it is a constant value. Put an inductor (or transformer winding) across a battery and you will get dc flux. ac flux is caused by ac current (flux and current are proportional), it is a moving value, the flux moves with the current, typically cyclical but the waveform is arbitrary as long as we're moving.
the efficiency of transformer is more than alternator, because 1- the alternator have friction and windage loss but in transformer this not occure. 2- in the alternator the flux leak is more than the transformer, because in case of alternator the flux move through the air which is dimagnet and in transformer flux move through silicon steel. 3- in the other hand alternator have dc compound generator for exciation (depend on other electric course 220volt) but in t/f is not need.