Reduced-order models for electro-magnetic-structural coupling phenomena

Electromagnetic devices such as electric machines are indispensable for vehicle electrification, power generation, and manufacturing. The distributed electromagnetic forces that exist in such devices can lead to structural deformations, particularly in devices with high power densities. These deformations may in turn lead to changes in electromagnetic forces. Consequently, the mechanical and electromagnetic behaviors are coupled, leading to electromagnetic-structural (EMS) phenomena. For an alternating current electric input, periodic forces generated by permanent magnets or windings and other disturbances to the electromagnetic device can lead to excitation of specific structural resonances due to the EMS coupling. In previous studies, the two-way coupling feedback between electromagnetic forces and structural deformations has been addressed using models with high computational cost. To address this issue, reduced-order models (ROMs) are proposed, which reduce the computational time of multi-physics analysis by projecting the equations of motion onto a modal space and/or using sector models for structures with cyclic symmetry. The multi-physics ROMs for EMS coupling are applied to investigate potential structural parametric excitations. This paper describes the construction of the multi-physics ROMs, and presents the findings of a stability analysis of systems susceptible to parametric resonance. In addition, parametric resonance is demonstrated using the proposed ROMs for a proof-of-concept design. The response predicted by the ROMs is verified using time domain analysis with high fidelity finite element models. Verification shows high computational accuracy and efficiency of the proposed ROMs. (c) 2021 Elsevier Ltd. All rights reserved.