AC MOTOR Russian patent published in 1997 - IPC

FIELD: electrical engineering; adjustable-speed ac motors. SUBSTANCE: motor armature mounts isolated internal and external annular magnetic cores with radial slots accommodating transformer secondary windings made in the form of figure-of-eight pole shaders wound on both magnetic cores; internal magnetic core accommodates two rigidly coupled transformers with U-shaped core and primary winding connected to external power circuit; transformers are free to turn within 90 deg. in either direction relative to motor shaft and to lock in any desired position. EFFECT: improved economic efficiency and stepless speed control within comprehensive range of its variation. 2 dwg