AXIAL AIR GAP BRUSHLESS ALTERNATOR

摘要

Brushless alternator volumetric efficiency is improved while increasing the radial field core dimension, thus preventing saturation and providing maximum alternator output. The alternator (10) has a stationary field coil (25) and field core (26) surrounded by a stationary coil (18) and core (19) with a cylindrical air gap being defined therebetween. A rotor assembly is fixed to a rotatable shaft (14) and has interweaved separate magnetic fingers (42, 43) joined together by a non-magnetic ring (44) wherein these fingers are rotated in the cylindrical gap. The stator and field core are radially disposed with respect to the rotatable shaft. The field core axially extends beyond the effective axial length of the field coil and provides at an axial position beyond the effective axial length of the field coil at least one low reluctance axial flux gap (53) between the field core and the magnetic fingers, for conducting a substantial portion of the flux created by the field.