Design of Interior Permanent-Magnet Machines with Novel Semi-Overlapping Windings

In this paper, a novel winding topology, comprising of semi-overlapped very short-end windings with significantly low magneto-motor force (MMF) harmonics, has been proposed. The key design rules, basic properties, advantages, and disadvantages of such a winding have been explained in detail. In order to reveal the key performance characteristics of the proposed winding topology, an interior permanent-magnet (IPM) machine with proposed winding structure is designed and the obtained results have been compared with other IPM machines having conventional distributed and concentrated fractional windings. It has been shown that the proposed winding topology promises significant advantages; such as improved efficiency with substantially reduced total axial length and low eddy current losses over conventional winding topologies.