Abstract:
This paper presents an improved model of permanent magnet synchronous motors (PMSMs)
considering core losses. The core losses of a surface mounted PMSM were measured at no-load
and load, and the analysis on experimental results shows that the core losses in a PMSM can be
attributed to the components produced by the rotor permanent magnets and the stator currents.
The conventional equivalent circuit model of PMSM with core loss can account for the former
but not the latter, and therefore, an additional core loss resistor is required to account for the
additional core loss component due to the armature reaction. The nonlinear resistance for the
no-load core loss is explained from the core loss model of magnetic materials. The method to
determine these core loss resistances from the no-load and load tests is also presented. The
relation between the core loss components and the corresponding resistors is clearly
demonstrated by the analysis of experimental results.
