Transformers- conservation of energy? (1 Viewer)

Sexygirl1989

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Hey can anyone explain to me how the action of transformers are related to conservation of energy? thx!
 

twilight1412

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this is simple concept

in a PERFECT world, which does not exist
where there is no energy lost to heat

in a transformer

Pin = Pout

where P is power which is Energy over time

P = E/T

and if

Pin = Pout

then energy is conserved
 

davidw89

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twilight1412 said:
this is simple concept

in a PERFECT world, which does not exist
where there is no energy lost to heat

in a transformer

Pin = Pout

where P is power which is Energy over time

P = E/T

and if

Pin = Pout

then energy is conserved
P=E/T??
 

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The ideal power input and output is 1:1 in, but output cannot be >1.
Whatever you supply in the transformer must be equal to the amount released, but there are other factors that affect the power output that decrease it, NEVER increase it.
You know one of the most important laws of physics don't you ? The Law of Energy Conservation ?

So the power supplied into the primary coils should be the same as the power released from the secondary coil, in an ideal transformer.
But that can't happen because eddy currents are created, causing around 1% of power to be dissipated as heat, a good transformer has a power input-output ratio of 1.00:0.95
 

airie

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The assumption that input power = output power must hold for that Vp/Vs = np/ns formula to hold, but conservation of energy from the primary coils to the secondary coils cannot hold if there is flux leakage. That's why you need soft iron core in both primary and secondary coils to act as a medium for power transfer, instead of just hollow coils.
 

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airie said:
The assumption that input power = output power must hold for that Vp/Vs = np/ns formula to hold, but conservation of energy from the primary coils to the secondary coils cannot hold if there is flux leakage. That's why you need soft iron core in both primary and secondary coils to act as a medium for power transfer, instead of just hollow coils.
And uhhh ... laminated as well to reduce the eddy currents because they represent heat loss. In large transformers, especially those in substations they may be oil or water cooled perhaps, again to dissipate heat and increase efficiency on a small scale.

Yes, I see iron cores there to help "propagate" or channel the magnetic flux to the other winding.
Only works with AC, no change in current then no change in magnetic flux, I think that's how you put it.
 

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