Losses and cooling of a high-speed and high-output power homopolar inductor alternator

In order to support development of a high-speed and high-output power homopolar inductor alternator (1000-1500 kW, 16000 RPM), substantial research and engineering analyses were made. Attention is paid to the electromagnetic and heat transfer phenomena. Analysis is oriented to the specific components of the total losses, namely to the stray-load losses, caused by eddy currents in the rotor surface, and to the aerodynamic friction losses, caused by air turbulence in the airgap and in the end winding spaces. The origin, main decisive factors and conditions for generation of losses in question are thoroughly investigated. It is shown that these two losses component determine temperature of the rotor and of the stator winding. Therefore they also determine the maximum output power of a homopolar inductor alternator