Novel energetic model of electrical machines using scaling of losses

The design and energetic evaluation of electric power train requires detailed energetic models of all the vehicle components connected to an entire vehicle model. The focus in modern vehicle propulsion lies on induction machines and permanent magnet synchronous machines. In the past these models where derived from measurements of the efficiency to obtain the losses over the whole operating range. To achieve a more flexible model that can predict the energetic behavior on the basis of few measured operating points a novel modeling approach based on scaling of losses is proposed within this work. Based on the nominal operating point and few additional parameters and assumptions the phasor diagram of the electrical machine is constructed. Scaling of the phasor diagram leads to the electrical behavior at the desired operating point. Depending on this behavior the losses are scaled as well. Experimental results show a good matching over the entire operating range.