Analytical prediction of eddy current losses in retaining sleeves for surface mounted PM synchronous machines

The aim of this paper is to investigate and evaluate the eddy current losses in conductive retaining sleeves of Permanent Magnet Synchronous Motors (PMSMs). High speed synchronous machines with surface-mounted PMs often require a bandage to fix the magnets to the rotor surface. A stainless steel sleeve is potentially a viable solution: the eddy current losses in this region are investigated using an analytical approach. The power losses due to the eddy-currents induced in the sleeve are evaluated in several different no-load and loaded working conditions. Finite-Element Method (FEM) simulations with two-dimensional and three-dimensional models validate the analytical results.