Fractional-slot and dead-coil windings

THE expression “fractional-slot windings” is commonly applied to machines where the number of slots is not an integer multiple of the product of the number of poles and phases. Dead-coil windings (D.W.) refer to windings where some of the slots contain wedges instead of coil sides. We shall use the term (F.W.) in this paper to comprise all windings which are not (D.W.). The term (F.W.) therefore comprises both whole-slot as well as fractional-slot windings which contain no dead coils.