Patent ID: 6483218
Filing Date: 2002-11-19
Classification: H01F,H02K

Abstract:
A brushless exciter for a dynamoelectric machine, the exciter comprising:a shaft adapted to rotate about a first axis; a cylindrical ferrite core mounted to the shaft and comprising essentially a toroid having an L-shaped cross section; a first transformer winding comprising a first conductor wound circumferentially about the ferrite core co-axial with the first axis and having a first diameter; a ferrite casing surrounding said ferrite core and adapted to remain stationary, the ferrite casing having a cylindrical inner surface coaxial with the first axis and comprising essentially a cup having an open end into which the ferrite core is inserted; and a second transformer winding comprising a second conductor mounted on the ferrite casing inner surface concentric with the first transformer winding and having a second diameter larger than the first diameter by an amount just sufficient for the first transformer winding to rotate without contacting the second transformer winding; wherein the ferrite core and the ferrite casing form a substantially complete enclosure for the first transformer winding and the second transformer winding.