GB981727A - A drum-shaped rotor for a high-speed synchronous machine - Google Patents

Abstract

981,727. Dynamo-electric machine rotors. LICENTIA PATENT-VERWALTUNGSG.m.b.H. July 28, 1961 [July 28, 1960], No. 27453/61. Heading H2A. The rotor for a synchronous machine comprises a central cylindrical body provided with a plurality of spaced circumferential rectangular grooves along its length and a plurality of stacks of annular segmental laminations arranged in each of the grooves and held therein by axially extending pins passing through both the central core and the segmental laminations, winding slots being formed in the stacks of laminations between their ends and the ends coinciding with the centre lines of the poles of the rotor. The core 1, which may comprise either a single mass of iron or a plurality of parallel laminations, is provided, as shown in axial section in Fig. 3, with a plurality of circumferential rectangular grooves 9 in each of which there are inserted six stacks 2 of segmental laminations arranged around the periphery of the core. Pins 3 are passed axially through the stacks 2 to retain them in the grooves. Slots are stamped in the laminations in which windings 4 retained by slot wedges 5 are accommodated. The slot wedges 5 may be composed of a non-magnetic conductive material so as to serve additionally as part of a damping winding. Further laminations 6 are inserted between the stacks 2 in their pole regions and are secured thereto by axial pins 7; alternatively the comb portions 10 of the core 1 may be extended to the air-gap in the regions of the poles. The winding slots are made wider than the windings accommodated therein thus leaving a cavity to each side of the winding so that lateral insulation of the windings is not needed and also so that, as shown in Fig. 4, moulded plastic spacers 8 used for retaining the windings in place and the slot wedges 5 may be shaped so as to cause air or cooling gas to circulate around the windings when the rotor is in motion.