Twelve‐slot two‐saliency variable reluctance resolver with non‐overlapping signal windings and axial flux excitation

Abstract

In this study, a new 12-slot two-saliency variable reluctance (VR) resolver with simple non-overlapping windings is proposed. The excitation winding in the proposed resolver is replaced with one axial coil that is perpendicular to the signal windings. Both distributed and non-overlapping concentric windings with uniform coil turns are used. The rotor has two upper and lower saliencies located in front of each other. The shape and width of each saliency are determined based on the optimisation. Compared with conventional 12-slot VR resolvers, the proposed resolver has a simpler rotor structure and the advantages of two-saliency resolvers against eccentricity, absolute output position, and higher accuracy. The operation principle of the proposed resolver is analytically shown. Then, a three-dimensional time-stepping finite-element method (FEM) is used for the design, analysis, and optimisation of the proposed sensor. After optimisation, a prototype of the most accurate resolver is built. The good agreement obtained between the FEM and the practical results verifies the design and optimisation process.