Comparison of Electromagnetic Performance according to Winding Configuration for Modular Dual 3-Phase Permanent Magnet Machines

Abstract

A new winding structure for modular dual 3-phase permanent magnet machine, which makes it possible to reduce mutual coupling between two-winding sets of inverters and interference between phases that belong to the same inverter has been proposed in this study. The modular dual 3-phase system with overlapping winding technique has been widely employed in large-scale machine applications such as wind power production; how-ever, its drawbacks include large torque ripple, long end-winding, and large magnetic mutual interference. To address these problems, a new modular dual 3-phase winding can be achieved by replacing adjacent redundant coils in one of the same phase coils with nonoverlapping winding. For clarity, three dual 3-phase machines are selected to examine their differences. The first is 32-poles/96-slots adopting a conventional overlapping modular winding ('Conv-1'), the second is 32-poles/36-slots based on the conventional nonoverlapping winding ('Conv-2'), and the other is 32-poles/36-slots adopting the proposed modular winding configuration ('Pro-posed'). The validity of the proposed structure is confirmed from simulation results obtained using finite element analysis.