Implementation of fractional slot concentrated windings to induction machines

The performance of an induction machine (IM), whose stator windings have been designed by using fractional slot concentrated winding (FSCW) technique, is investigated. Well known several advantages of FSCWs, including higher slot fill factor, better flux-weakening capability, higher power density, non-overlapping end turns, higher efficiency, are attempted to bring in IMs. However, detailed performance analyses including 3-phase short circuit fault analysis of the IMs designed with FSCWs have not been addressed in literature. In order to reveal the potential merits and demerits of the FSCWs when used in IMs, a conventional slot distributed winding (CSDW) IM having the same rated output values has also been designed and all results obtained from simulation have been compared. The comparison includes detailed machine dimensions, weights, magnetic flux density and line distributions, losses, efficiency, torque-speed curves, torque ripple levels, and also magnitude of forces acting on the stator and rotor windings under the steady-state and fault conditions. All simulations have been built in ANSYS Maxwell® electromagnetic field simulation software based on finite element method. This study will assist in answering lots of the questions raised about the advantages and disadvantages of using FSCWs in the IMs.