Modeling and reduction of stator teeth eddy-current losses in IPM machines

A known drawback of interior permanent magnet synchronous machines are the high eddy-current losses in the stator teeth, especially in the field-weakening region. For a deep analysis of this phenomenon, an analytic loss modeling approach solely based on fundamental machine parameters like the inductances, the permanent magnet flux, and the magnet configuration is derived. Due to its formulation, the method allows a hybrid modeling with numerically calculated inductances and thus yields reasonable results even at the presence of saturation. It provides a deep understanding of key influencing parameters and reveals the dependency of eddy-current losses in the stator teeth on the direct and quadrature component of the stator current. Different parameter studies are performed with the model and compared to FEM simulations to underline the validity of the derived formulation.