Introducing New Three Phase Fractional Slot Windings With Low Space Harmonic Contents

One of the most effective winding type for use in electric machines is fractional slot concentrated winding (FSCW). These winding type prepares the shortest end-winding length for electric machines. In addition, they can tolerate the fault condition more in compare to other windings type. Besides, higher copper fill factor, lower cogging torque, simple construction and field weakening capability are another merits of FSCWs. Unfortunately, in compare to conventional distributed-windings, FSCWs have high space Magnetomotive Force harmonics (MMF harmonics). These unwanted harmonics will cause core saturation (localized saturation), mechanical vibration, acoustic noise and iron losses. In order to develop winding benefits, many methods have been introduced. This manuscript introduces some new three-phase windings, by using the stator slot shifting concept. The novelty of this paper is introducing some new winding topologies for the first time. An analytical study and the 2-D FEM are applied to three sample-designed synchronous reluctance machines to evaluate the new winding's characteristics as case studies.