A Five-Phase Two-Motor Centre-Driven Winder with Series-Connected Motors

Application of power electronics in variable speed electric drives enables utilization of ac machines with a phase number higher than three. It then becomes possible to use the additional degrees of freedom, available in multi-phase systems, to control other motors within a multi-motor drive. The paper deals with a two-motor five-phase drive system with series connection of stator windings, where an appropriate phase transposition in the series connection enables independent vector control of the two machines, while using a single five-phase voltage source inverter (VSI) as the supply. It has been suggested that such a drive system may offer a saving in the installed inverter power in winder applications, when compared to the standard solution with two three-phase motors supplied by two three-phase VSIs. The paper investigates the applicability of this drive configuration for a specific constant-power two-motor centre-driven winder and highlights the advantages offered by the two-motor five-phase series-connected topology.