Influence of winding design on the axial flux in laminated-stator cores

The magnetic field of an isolated winding of helical form is obtained both theoretically and by measurement on a small model. The axial and radial fields of that winding are compared with those of straight windings with conventional ends, both when the windings are in air, and inside a slotless, laminated core. It is found that a knowledge of the field in air of a winding is not of itself helpful in predicting the axial-field distribution when the winding is placed inside a laminated core. Experimental results of the axial-flux distribution inside the core are also presented. They demonstrate that axial flux is reduced when the winding radius and overhang are reduced. The axial flux continues to decrease even when the endwinding ceases to project from the core end.