Operation of induction machine with combined star delta stator winding

An induction machine with combined star-delta stator winding is analyzed in the paper. This type of winding is used in order to suppress the selected groups of higher spatial harmonics of the current layer, magnetic flux density in the air gap, and the flux in the yoke and thus lower the losses and improve the energy efficiency. The mathematical model of the machine has been developed. The possibility to suppress higher harmonics in such machines has been demonstrated. The validity of the equations has been verified by experimental measurements on a physical model of the machine.