Spiral core made of grain-oriented electrical steel sheet

Abstract

Spiral cores made of grain-oriented electrical steel sheets (GO) were developed to be used as a high performance motor core. All teeth directions are coincident with the GO rolling directions (easy magnetization axis) in the spiral cores. The GO spiral cores have excellent properties because the GO has very low iron loss and very high permeability in the rolling direction. In the GO spiral cores, the iron losses decrease to a quarter and the inductions are 0.2 T higher at 800 A/m as compared with conventional spiral cores made usually of SPCC. Because the thickness of conventional spiral cores generally varies, applications are limited to automobile alternator cores. The thickness of GO spiral cores changes little during a spiral deformation because the core sheets are deformed transversely to the rolling direction of GO, that is, {011}; the {011} deformation of Fe does not create sheet thickness. As the stiffness and packing factor of a GO spiral core are high in the order of no thickness change, GO spiral cores have high performance for motor cores. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 118 (3): 58–66, 1997