Design Principles of Flux-Switch Alternators [includes discussion]

The general problem of the design of a peak-power minimum-volume high-frequency alternator which employs the flux-switch principle is discussed. Included in this paper are analyses of general configuration, generated voltage and frequency, magnetic circuit, generator losses, and materials. A design procedure which employs the use of a set of empirically derived constants which determine various mechanical and electrical parameters is presented. The design charts can be used for flux-switch alternators ranging in power from 100 to 5,000 watts and for shaft speeds from 10,000 to 50,000 rpm. A sample design based on the use of the design charts is developed for a 50,000-rpm 3-kw 250-volt single-phase flux-switch alternator with permanent magnet excitation.