A design approach to reduce rotor losses in high-speed permanent magnet machine for turbo-compressor

In this paper, a design approach to reduce rotor losses in high-speed permanent magnet machines for turbo-compressor is discussed. In particular, the influence of materials chosen for the retaining sleeve is highlighted. The two topologies of high-speed permanent magnet machines with Inconel718 and Carbon-Fiber/Epoxy sleeves are employed for comparison of computed rotor losses by two-dimensional finite-element method and analytical field anaysis. It is shown that the Carbon-Fiber/Epoxy is superior to Inconel718 in terms of reducing rotor losses.