Study on the Optimal Design of a Novel Slotless Resolver by FEM

An effective design method of a novel slotless resolver with a variable reluctance rotor is proposed using the finite-element method (FEM). The slotless resolver has an advantage in size, precision, and manufacturing cost over a general slot-type resolver. In designing the slotless resolver, the virtual slot section is introduced to wind the excitation coil, as well as the sin and cos output signal coils. The effective winding methods relative to coil position and coil turns in the virtual slot section are proposed to obtain precise position angle information of the resolver using FEM. To validate the proposed design method, the prototype slotless resolver with winding pattern in a flexible printed circuit board is tested, and the experimental result is compared with the simulation result.