tansformer query
In case of designing SMPS...
1. To get design tool from SMPS IC maker.
2. To make sample and test good or not
---> normally a little good , need to tune something
At this point you need to know the parameter that you want to know.
1) hysterises losses
frequency is high ---> increase the loss and make heat
it is similiar to an iron spring tesion.
You have to check switching frequency and the matched frequence to TRANSFORMER.
2) eddy currents (loss)
It is the sensitive point for designing transformer
the iron core is normally laminated to decrease this loss, but ferrite is not.
To prevent generating EMI encapsule the coil; it is eddy current.
3) no load losses
Energy transformation will make loss all the times
In case of transformer, it is very littile but second voltage is high. Anyway even though making loss, you add dummy load to second voltage circuit.
4) primary resistive looses
the primary coil DC resistance.
P = I*I*R (this is also loss)
You should make lessen R ---> coil turns related
5) One more thing
E and I core is normally used to make transformer. sometimes insert film between E and I core. (It will be increase switching frequency)