Adjustable-speed drives with multiphase motors

Abstract

A new theory for multiphase motors which takes into account current harmonics and all space harmonics of the magnetomotive force (MMF) is presented. It is shown that a multiphase motor for an adjustable speed drive (ASD) should have a full pitch or nearly full pitch winding with nearly rectangular space distribution of the phase MMF. The results can be used in the design of ASDs with induction, synchronous and permanent magnet motors.