Electrical – Push Pull Converter Transformer Saturation Rating

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How do you determine the required saturation rating for a transformer to be used in a push pull converter? Can a transformer in this topology pass more than the saturation rating since it is not storing the energy as it would in a flyback type converter?

Some background:
I am building a push pull converter that will take 24V at up to 1A peak and convert it to 15V. I found a transformer (VPH5-1200-R) with a RMS current rating of 1.7A but a saturation current rating of only 0.14A. Will this transformer saturate out before it reaches the 1A through the primary?

Best Answer

You need to do some learning here. Transformer saturation is almost 100% unrelated to load currents. If you apply a voltage to the primary, with the secondary unloaded, it will (largely) saturate no more or no less than under full load conditions.

I know this sounds unintuitive but any current in the primary that is due to secondary load current produces a magnetic field that is totally cancelled by the magnetic field produced by secondary current.

If this were not the case then Faraday's law of induction would be violated.