On the analytical estimation of the airgap field in synchronous reluctance machine

Synchronous reluctance motors with rotor flux barriers are a promising type of electric machines thanks to various benefits, among the others, the absence of permanent magnets and rotor excitation. A challenge in the study of these motors is the accurate prediction of their air-gap field analytically taking into proper account the effects of rotor flux barriers. This paper proposes a technique for this purpose based on reluctance network solution and winding functions. The reluctance associated to each flux barrier is computed by means of conformal mapping. Furthermore, the slotting effect is also considered through appropriate permeance function definition. Analytical results are compared to finite element analysis showing a good matching for various machine topologies characterized by a different number of flux barriers.