ELECTRIC MACHINE Russian patent published in 2014 - IPC H02K9/12 H02K5/16 H02K21/12 

FIELD: electricity.

SUBSTANCE: electric machine includes case with end screens, housing a laminated stator core with slots where winding coils are located and fixated by wedges, with rotor positioned inside stator cavity and including inducer actuating poles, permanent magnets, no-magnetic wedges and shaft, so that rotor length exceeds inducer length. Rotor end sections are made in the form of cylindrical bushings out of non-magnetic material, flush-mounted on external surface of inducer, rotor bearing unit allows for static gas and dynamic gas support, and for that purpose external rotor features cylindrical surface and is positioned inside cylindrical cavity of the bushing fixated in the stator cavity with gas supply for stator surface cooling, while case cavity has cooling gas supply and drain, and for that purpose internal surface of the case features longitudinal ducts joining radial ventilation ducts made between stator core stacks. According to invention, stator can be vented separately by at least two pipes in the case for cooling gas supply/drain to/from the case volume occupied by the stator, the bushing has longitudinal lugs matching stator core slots in number, positions and cross-section and fit into the slots, slot vent gap is left between lug surface and slot wedge, lengthwise holes are made in longitudinal lugs of the bushing and connect to radial feed orifices opened into internal cavity of the bushing, cylindrical bushings out of isolating material are installed in the case cavity coaxially to stator core cavity and attached by their ends to the ends of outmost stator core stacks, external surface on the ends facing end screens feature o-ring pairs, and end screen junction with the case is sealed. Cylindrical bushings serve as external cartridges of radial gas-dynamic leaf bearings, and rotor end sections serve as trunnions of the bearings, in addition the electric machine features at least one axial gas-dynamic leaf bearing, and orifices are made in end screens, with orifice inlets connected to lubricating gas source and outputs joining annular slot between o-ring pairs, which in its turn joins longitudinal through holes of the cylindrical bushing. Besides, a screen features pipe connected to separate source of cooling gas and joining permanent magnet cooling ducts formed by slot bottom section and permanent magnet surface facing them, via end sections of inducer, and at the opposite case end the ducts are connected to process gap of axial gas-dynamic leaf bearing which in its turn is connected to gas collector.

EFFECT: efficient cooling of stator winding and core, reduced weight and dimensions, improved service life of electric machines, minimum rotor bend, efficient cooling of permanent magnets, extended rotor stability range due to damping by radial gas-dynamic leaf bearings, prevention of rotor jamming at high circular velocities in vicinity of gas-dynamic leaf bearings.

4 cl, 3 dwg