Torque ripple reduction in interior permanent magnet synchronous machines with single-layer fractional slot concentrated windings

High power density and reliability associated with single-layer fractional slot concentrated winding interior permanent magnet synchronous machines make them appealing for automotive and aerospace applications; however, the associated magnetomotive force contains extra harmonic components that result in higher torque ripple. Mechanical vibrations, acoustic noise and bearing damage are often caused by torque ripple and can significantly reduce the life of the machine. In this paper, a priori estimation of torque ripple is used to decrease the torque ripple of a single-layer fractional slot concentrated winding design. Finite element and experimental results are presented demonstrating that the control technique is effective. The losses associated with this controller are also evaluated.