INDUCTION MACHINE Russian patent published in 1997 - IPC

FIELD: variable-speed electric drives or AC generators with regulated output characteristics of generated electricity at variable speed of prime mover. SUBSTANCE: stator has, apart from main magnetic circuit 1 carrying AC winding 2, also additional magnetic core 3 on unipolar machines with two unipolar ring-type field windings 4 and 5 and two unipolar modules 6, 7 which are, essentially, self-contained structural assemblies. First unipolar module 6 incorporates sealed chamber 14 formed by external hollow barrel 15 of additional magnetic core 16 of stator rigidly secured to fixed part of sliding contact member in the form of fifth ferromagnetic barrel 17 with nonmagnetic conducting bars, butt-end rings 19 and adjacent end rings 20, as well as first part of internal barrel 21 with butt-end ring 22 and adjacent end ring 23 bearing insulation 24, first ferromagnetic barrel 25 and second one 26; chamber is filled with liquid metal. Second unipolar module 7 has similar structural parts. Apart from main magnetic core 8 with winding, rotor has three additional magnetic cores 9, 10, 11. Fourth ferromagnetic barrel 37 of second unipolar module 7 is divided along generating line into insulated parts, as many as there are teeth on rotor toothed magnetic core 11 so that single-turn coils are formed for unlike-polarity magnetic system similar to first ferromagnetic barrel 25 of first unipolar module 6. Speed is controlled by varying current through unipolar field winding 5. EFFECT: facilitated speed control. 2 dwg