ABSTRACT
The inverse d-q transformation is used to develop pole-changing 3-phase induction motors from change-pole 2-phase ones. Transformation procedures, common features of the original 2-phase and derived 3-phase windings, basic differences between derived and conventional 3-phase windings together with their limitations are discussed in detail. Single winding change pole arrangements for 3-phase machines are derived from 2-phase ones. In addition, a mathematical model is presented to take satisfactorily into account the effects of unbalanced impedances and multi harmonic interactions. Tests conducted both in 2 and 3-phase operations on a 10/6 change-pole machine are reported. The nature of agreement between the computed and experimental results validates the transformation technique and also the mathematical model used in the process.