Improved Configuration Proposal for Axial Reluctance Resolver Using 3-D Magnetic Equivalent Circuit Model and Winding Function Approach

Resolver is a position sensor that is widely employed in motor servo systems under harsh working conditions. In this article, a novel axial flux resolver with a fractional-slot sinusoidal distributed winding configuration is developed, which has the advantages of a simple structure and convenient mass production. Sinusoidal distribution winding expands the optional range of pole-slot combinations, and its harmonic suppression capability is proposed and verified by the winding function approach (WFA). Furthermore, the magnetic equivalent circuit (MEC) model is formulated to analyze the impact of structural parameters on the induced voltage envelope, through which the optimal parameters on the resolver are developed. In terms of computation time and accuracy, the results of the MEC model under healthy and eccentric conditions are compared with the finite-element method (FEM). In addition, the antiaxial offset capability of the half-wave resolver is illustrated and verified. The effectiveness and superiority of the proposed resolver are illustrated and verified based on numerical simulations and experimental tests.