Current harmonics in induction machine with closed-slot rotor

Usually an induction machine with closed slots on rotor has lower harmonics in line currents than that with open slots. However, in this paper, finite element analysis shows that some induction motors with single-layer windings may have an opposite characteristic, say, such motors with closed slots exhibit significant 5^th- and 7^th-order harmonics. This phenomenon is explained with theoretical analysis and validated with experiments. The study is of reference value for the induction motor design.