I’m trying to simulate a thermal model of the transformer using PLECS. I was able to model the power losses (from core, winding, etc.), conduction thermal resistances and ambient as a thermal voltage source.

However, I’m facing problem while modelling convection and radiation parameters as these depend on the differential temperature between the surface and the ambient. Since the surface temperature would be unknown, I was wondering how to do that to complete my model. Or if there exists an alternative to do that which I might have missed.

Thank you!

Best Regards, Suyash