Analysis and Reduction of Zeroth‐Order Vibration in Integer Slot Distributed Salient‐Pole Wound Field Synchronous Machines

ABSTRACT The zeroth‐order vibration and noise are worthy of attention in integer slot motor vibration when it is applied to underwater vehicles. In this article, the source of the zeroth‐order vibration and the deep relationship between the rotor modulation and the radial force are demonstrated for the wound field synchronous machines (WFSM). First, based on the Maxwell tensor method and the modulation effect of the stator and rotor teeth, the generation mechanism of zeroth‐order vibration on the WFSM is clarified. Then, taking an integer slot distributed salient pole WFSM as an example, based on the modulation effect of the rotor teeth on the radial force density, the weakening mechanism of the zeroth‐order vibration is demonstrated in detail. The rotor structural parameters of the distributed salient pole WFSM are adjusted to weaken zeroth‐order vibration. In the finite element model, the radial force influence components of the zeroth‐order vibration, key electromagnetic performance, and vibration spectrum of the machine before and after improvement are compared. Finally, the vibration experiment on the prototype is carried out to verify the correctness and effectiveness of the analysis and improvement.