Why the transformer will burn if DC supply is given?

If DC supply is fed to a transformer's primary, then inductive reactance X1 and magnetising reactance X0 becomes zero. The no load branch contain a parallel combination of R0 and X0. As X0 is zero so that the impedance of no load branch is zero. and current being the ratio of Supply Voltage and no load impedance is very high as it burn the primary winding.

Xl=2*3.14*f*L

where the frequency of DC supply is zero,so the impedance will be zero

so Xl=0,it mean that no impedance against current ,so the current will be so biggest so it lead to damage coli and conductors (winding)

it will damage all primary stage of transformer

because the main power content will be dessipated in the form of heat.. the heat generated will further melt the insulation between the wires in coil..finally full coil which was been wounded as coil or turns will act as the single conductor

for transformation action u need to have flux changing "WITH RESPECT TO TIME" /i.e instantaneous ..iin theory we say dc pulse require no time for transition..but practically it does take..so some emf will be indused.. it will get damaged in few cycles only due to constant pulse for a time interval

If we give a DC voltage, the transformer coil will function as pure resistive load and reactance will be neglected and thereby producing large currents that will able the winding to be more heated as pure resistive load, and high core loss as high flux disipated by hysteresis loss.

because it will create high current passing through the transformer coiles

It may burn as Transformer Winding shows high Inductive Impedance to AC Supply,

 

But for DC Supply, Inductive Impedence is very very small & hence High DC current may flow leading to Winding Burn out due to Heating of Winding ..........

 

Dear,

I have two researches about it, one it will not damage because

1- According to the principle the alternating voltage in primary will generate a magnetic field which induces voltage in the secondary and thus the secondary voltage is generated. But if you give a DC supply , the DC voltage doesnt change , it just generates magnetic field in the core which will generate a pulse at the secondary. But the secondary voltage will be zero after the pulse may be because of the static secondary magnetic field. Transformers will work on DC a bit ineffectively , we can make them work giving DC series of pulses.

This theory applies in VFDs.

 

Second theory is it will damage, because:

2- If we give dc supply, because the main power content will be dissipated in the form of heat;the heat generated will further melt the insulation between the wires in coil..finally full coil which was been wounded as coil or turns will act as the single conductor.

 

Good Luck

transformer winding burn only because of high current . now if we apply same ammount of dc voltage say we applied230 volt dc insted of ac then avg volatge applied to winding is more and due to dc there is no impedance as frequency is zero so current increses and due to this heat produces in winding and insualtion got damaged 

ampere is the amount of current flowing through two straight parallel conductors 1 meter apart in a vacuum which produces a force 2 × 10-7 newtons per meter of conductor.

If DC is applied to the transformer winding then high current flows as there is no back emf produced to limit the current and hence the winding burns out. 

 

Where as when AC current flows in to primary winding it induces an alternating flux which also links with the secondary winding, and so secondary current flow in secondary winding due to primary current. Again the secondary current also induces an emf (Back emf) in secondary winding which opposes the induced emf of primary winding and thus controls the primary current.