# Transformer

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What happens to the energy loss if the iron core in a transformer is taken out? I think the energy loss will reduce, is it right?

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hello people. Long time

As far as I know, a transformer cannot function without a soft iron core. This is because the e.m.f in the primary coil induces a magnetic field on the iron that then induces an e.m.f in the secondary coil. So I don't see how a transformer could work without that.

And besides, the loss due to eddy fields and heat, etc. are so small that they are negligible in most cases. Therefore a transformer's efficiency is about 95-98 %. Can someone pls. verify this ?

So there is no real need for removing the iron core even for efficiency reasons.

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it all depends on what frequencies youre running at, Air Core transformers exist

they are often for high frequency applications where a Core (iron or ferrite) would Decrease their efficiency.

take a look here, you should find this interesting: http://www.allaboutcircuits.com/vol_2/chpt_9/7.html

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it all depends on what frequencies youre running at, Air Core transformers exist

they are often for high frequency applications where a Core (iron or ferrite) would Decrease their efficiency.

Yes, air core transformer exists. Generally, air-core transformers are used when the voltage source has a high frequency (above 20 kHz). Iron-core transformers are usually used when the source frequency is low (below 20 kHz

I've got a look at it,but I still can't figure out the answer.

Is it all the P=[power given out by the primary transformer minus power loss by the main three ways]must be absorbed in the secondary circuit whatever the load is?

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The iron core concentrates the field lines, so that the secondary sees a larger field, and thus a larger changing field, so Faraday's law tells you you get a larger voltage out the other side. If you take the core out the load is reduced, so I think you will just draw less current in the primary.

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actualy removal of the core will cause the primary to burn out, its value in Henries will alter, as will its imepedance for the application it was matched for and simply get Very hot and burn out (Ive tried before many years ago), in general, they Dont Like It!

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V1/V2=N1/N2

This can be applied only when the magnetic flux does not pass to other objects except the 2nd coil?

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• 3 years later...

hello,

I am doing project for my 3rd year about the transformer.I attached the equivalent circuit in my attachment.

I have several question to ask,

1)how to calculate the transfer function from the circuit so I can manage to get the resonant frequency?

2)Is transfer function in this circuit same with its gain?

Thanks..

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