Design of Novel Axial-Flux Dual Stator Doubly Fed Reluctance Machine

Abstract

This paper proposes a novel machine termed the axial-flux brushless doubly fed reluctance machine (AF-BDFRM) suitable for high-torque, low-speed direct drive applications. The main potential advantages of AF-BDFRM are its higher torque and power density compared with the radial-flux BDFRM. In addition, the proposed machine utilizes a bidirectional power converter of much lower rating as compared with the machine rating depending on the range of speed variation. The proposed machine axial-flux topology is composed of two stators and a reluctance iron rotor. The upper stator winding which is connected directly to the power grid, transfers active power to the grid and lower stator winding creates excitation for the machine and connects to the grid through a partially rated converter. The design principles of the proposed AF-BDFRM are studied in this paper. Furthermore, the transient 3-D finite-element analysis result of the improved design is presented.