Analytical Evaluation of Flux-Linkages and Electromotive Forces in Synchronous Machines Considering Slotting, Saliency and Saturation Effects

An analytical approach to the evaluation of flux linkages and e.m.f.s in salient-pole synchronous machines is developed, capable to accurately allow for the actual winding structure, the stator and rotor airgap geometry (slotting and saliency), under any saturated, steady-state or transient operating condition. The method is based on a Park d-q decomposition of the stator m.m.f. distribution (preserving the spatial harmonics) and on the use of FEM identified saturation functions. A relevant feature is that the self and mutual inductances, evaluated in unsaturated conditions, are simply corrected by using the saturation functions. Several transient FEM simulations validate the method.