A New Structure of a Gap-Reactor to Reduce Electromagnetic Vibrations

Abstract

Magnetostriction is an inherent property of an electrical steel sheet (ESS). Experimental measurements have revealed that the magnetostrictions of Grain-oriented and Non-oriented ESSs are mostly opposite in their directions. Based on this, a novel structure of gap reactor is suggested to reduce the mechanical vibration of the reactor. The new structure follows the conventional manufacturing process, and is built by stacking Grain-oriented and Non-oriented cores alternately while a conventional one is by only Grain-oriented or Non-oriented core. In order to verify the effectiveness of the proposed structure, the electromagnetic vibration, stress and displacement of the reactor are analyzed based on the magneto-elastic coupled analysis. The measured magnetization and magnetostriction data of the ESSs are adopted during the numerical calculation. Prototypes of new and traditional structures with the same design parameters were also built and electromagnetic-induced vibration were measured and analyzed. Both the computational and experimental results showed that the proposed structure made much less electromagnetic vibration than the conventional one. Moreover, the noise level around the reactors were measured and the average noise level around the improved prototype was reduced by 16.7%.