Characteristics analysis of a novel two-phase SRM with T-type rotor pole surface

In this paper, a novel two-phase switched reluctance motor (SRM) with T-type rotor pole surface is proposed for a high speed air blower. The air blower has unidirectional rotation and requires a wide positive torque region without torque dead zone. To achieve the requirements, asymmetric inductance profile is considered. Unlike the previous research method, which tries to modify the air-gap to get the asymmetric inductance, the proposed method tries to keep the constant air-gap and modify the stack length of the rotor according to the rotor position to acquire the asymmetric inductance. Compared with stepper type, the proposed structure not only inherits the torque characteristics of the stepper type, but also improves the utilization of the material. That is, the material used in the proposed type is less than that in the stepper type. To verify the validity of the proposed structure, finite element method (FEM) is employed to get the characteristics of the conventional, stepper type and proposed SRM. Finally, the simulation results verify the validity of the proposed structure.