GB1489772A - Electromagnetic machines - Google Patents

Abstract

1489772 Cooling electromagnetic machines MARKON ENG CO Ltd 25 July 1975 [18 May 1974] 22271/74 Heading H2A Cooling of a salient pole rotor 10 of an electromagnetic machine having an impellor for directing a flow of coolant gas through the machine is improved by heat pipe structures 16 carried by the windings 13 on the salient pole 11, each structure 16 being positioned with its evaporator end 17 within the corresponding winding 13 and its condenser end 15 projecting out of the corresponding winding 13 and into the coolant gas flow path. Each structure 16 has its evaporator end 17 further from the rotor axis than its condenser end 15. Each pole 11 may have two structures 16, Figs. 2 and 3 (not shown) and Fig. 4, each formed from a plurality of abutting elements (16<SP>1</SP>), Fig. 3, with the evaporator ends 17 adjacent the pole shoes 12 and the evaporator-condenser end direction parallel to a radius to the rotor axis 2. The elements (16<SP>1</SP>) may be of equal thickness to rectangular section strip material forming windings 13. Alternatively the structure 16 may be oriented with the evaporator-condenser end directions extending generally longitudinaally of the rotor in which case each pole 11 may have four structures 16 in two back-to-back pairs with the evaporator ends 17 axially central of the rotor and the condenser ends 15 near the axial ends of the rotor, Figs. 5, 7, and 8 (not shown), and Fig. 6. Structures 16 each comprising a plurality of heat pipe elements in parallel, or each having an evaporator end centrally located between a pair of condenser ends, may also be used. The rotor may be completely laminated, or substantially solid but with laminated pole shoes 12.