Investigation of Winding Configuration on Electromagnetic Vibration in Modular Dual Three-Phase PM Machine

This article investigates the effect of winding configuration on the electromagnetic vibration of the 48-slot/8-pole modular dual three-phase (DTP) permanent magnet (PM) machine. First, two winding topologies are discussed based on the phase shift principle, and their phase shift angles are 30° and 60°, respectively. Second, the armature magnetomotive force (MMF) of different winding configurations is derived and compared. The modular DTP-PM machine with 30° phase shift produces the extra 2nd, 18th, 22nd, 26th, and 30th armature MMF harmonic components compared with the 60° phase shift one. Afterward, the electromagnetic force density and radial concentrated force of two modular DTP-PM machines are investigated. The result reveals that the modular DTP-PM machine with 30° phase shift induces the non-negligible 2nd-order vibration under the load condition. This is different from the modular DTP-PM machine with a 60° phase shift which mainly induces 0th-order vibration. Furthermore, the multiphysics field finite-element method is used to calculate the static deformation and vibration acceleration of two modular DTP-PM machines. Finally, the prototype of a 48-slot/8-pole modular DTP-PM machine with a 30° phase shift is manufactured. The experiments are conducted to validate the theoretical analysis.