What happens when a Transformer is Saturated?
The transformer core is composed of ferromagnetic materials that become saturated at specific magnetic flux densities.
Increasing the mmf does not result in a corresponding rise in magnetic field flux (Φ).
Each kind of core has its unique capacity to handle flux density.
It also has its own saturation characteristics:
Flux vs. Magnetizing Current,
where flux depends on supply frequency,
Flux = Voltage/Frequency
If the frequency reaches 0, the core enters the saturation area.
i.e., Pure D.C. supply has no frequency, so never try to supply D.C. to the transformer.
The same method The Imsin(Ꝋ) component is exactly proportional to flux, therefore once it increases to a certain level, the core will become saturated. where that is the power factor angle.