Fundamental study on rotor eddy current losses in high frequency machines due to current harmonics

The main goal of this paper is to fundamentally address the behavior of the extra eddy current losses in a high speed/frequency synchronous reluctance machine (HS-SynRM). Both stator core and rotor eddy current solid losses, due to the current harmonics, under Variable Speed Drive (VSD) operation, have been studied. First, the root-cause of these losses is explained and developed through an analytical and qualitative approach. Then, the 3D Finite Element Method (FEM) based simulations are used to quantify the extra eddy losses. Afterward, finding and investigating some solutions for reduction of the eddy current losses are followed. The last goal is to introduce, distinguish and develop simple means, tools and methods for dimensioning the solutions for eddy current reduction.