Novel modular design of a position-sensing resolver

The paper considers an idea of novel modular approach to a resolver design. The rotor of the resolver represents a simple piece of laminated steel with variable reluctance as in commercial resolvers. The stator part, however, is different. Each stator tooth is replaced with an H-core segment, which contains two windings: excitation and sensing. The design is unified in such a way that the same cores can be used in manufacturing resolvers of different sizes with different pole numbers. The size of the stator is significantly reduced because it can cover only about one saliency pitch of resolver. The solution is especially advantageous in electrical drives where the motor has a large number of poles. However, the side effect, which has a negative impact on the accuracy of a resolver with the proposed stator, should be considered during the design. The side effect is analyzed in the proposed resolver structure using the finite element method (FEM) and some approaches to reduce its negative effect are proposed.