Design Principles of Flux-Switch Alternators [includes discussion]

TLDR

The paper discusses the challenge of designing peak‑power, minimum‑volume high‑frequency alternators using the flux‑switch principle. It presents a design procedure that uses empirically derived constants to determine mechanical and electrical parameters. The authors analyze configuration, voltage, frequency, magnetic circuit, losses, and materials, and provide design charts and a sample design for a 50,000‑rpm 3‑kW alternator. The design charts enable flux‑switch alternators from 100 to 5,000 W at shaft speeds of 10,000–50,000 rpm.

Abstract

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.