Magnetic-coupling characteristics analysis of a dual redundancy axial flux permanent magnet synchronous motor

Abstract

The permanent magnet synchronous motor (PMSM) is widely used as the driving device for electric vehicles, robots and other systems due to their high-power density and wide speed range. In order to improve the reliability of PMSM, redundant structure can be used. In this paper, a topology of dual-redundant axial flux PMSM (DR-AFPMSM) and a analytical method for magnetic coupling characteristics was proposed. To reduce the axial length and the magnetic coupling between the two redundancies, the middle rotor disk consists of a set of permanent magnets (PMs) embedded in a coreless skeleton. From the perspective of inductance and armature reaction, the magnetic characteristics of each redundancy and the magnetic coupling between redundancies have been analyzed by 3-dimensional finite element analysis (3D-FEA) in this paper. Tests under different conditions, namely no-load, load, and phase-to-phase short-circuit have been carried out. Results show that the prototype meets the design requirements and the proposed structure can effectively decrease the magnetic coupling between the two redundancies.

Keywords

• Permanent magnet synchronous motor
• Dual redundancy
• Magnetic coupling
• Finite-element method (FEM)
• Self-inductance and mutual-inductance