A contactless energy transmission system is essential to supply onboard systems of electromagnetically levitated vehicles without physical contact to the guide rail. One of the possibilities to realise a contactless power supply (CPS) is by integrating the primary actuator into the guide rail of an electromagnetic guiding system (MGS). The secondary actuator is mounted on the elevator car. During the energy transmission, load dependent non-linear losses occur in the guide rail. The additional losses, which are caused by the leakage flux penetrating into the guide rail, cannot be modelled using the classical approach of iron losses in the equivalent circuit of a transformer, which is a constant parallel resistance to the mutual inductance. This paper introduces an approach for modelling the load dependent non-linear losses occurring in the guide rail using additional variable discrete circuit elements.