Calculation of eddy current losses in conductive sleeves of synchronous machines

In this paper, analytical and finite element method (FEM) approaches to calculation of eddy current losses in conductive non-magnetic sleeves (cans) of synchronous or induction machines are presented. Those losses are especially important in high speed electrical machines as the sleeve losses are a function of the second power of rotational speed. In some applications, non-conductive sleeves, e.g. carbon graphite cannot be used due to problems with thermal compatibility of rotor and stator materials.