A critique of Steinmetz model as a power transformer representation

When teaching transformer theory it is essential to discuss the Steinmetz t ransformer model. This representation forms a basis for understanding most of the transformer's electrical behaviour. However, care must be exercised when explaining the shunt magnetising and series leakage reactance componen ts of the Steinmetz model. The Steinmetz shunt and series branches will acc urately represent the mutual and leakage flux circuits respectively, of an iron core transformer. But for the air or partially cored transformer, this may not be the case.