Design and Optimization of a Multi-Turn Variable Reluctance Resolver

Multi-turn resolvers are supposed to be used in high accuracy industrial applications where both the high resolution and the absolute measurement are needed. The existed multi-turn resolvers are wound-rotor (WR) resolvers, while the variable reluctance (VR) resolvers are expected to be more cost efficient than WR resolvers, because they have a simple and solid rotor that makes them independent of using the rotary transformer. In this paper, a multi-turn VR resolver is proposed for such applications. Then, the proposed structure is optimized to decrease the ferromagnetic material's volume and improve the performance of the sensor under mechanical faults. The studied mechanical faults include run out, static, dynamic, and mixed eccentricities that are studied independently and simultaneously. The analysis is done using three-dimensional time-stepping finite-element method (3-D TSFEM), and the optimal structure is experimentally built to validate the success of the design and optimizations.