Reduction Method of Torque Ripple, DC Current Ripple, and Radial Force Ripple with Control Flexibility of Five-Phase SRM

This paper proposes a torque ripple, DC current ripple, and radial force ripple reduction method with five-phase switched reluctance motor (SRM). The proposed method makes these three ripples simultaneously zero, which is so-called "triple zero" in this paper, by improving control flexibility with five-phase. In particular, the triple zero is achieved with the same efficiency as the general driving method of SRM by utilizing the control flexibility effectively. A three-phase 18S/12P type SRM and a five-phase 20S/16P type SRM are used in finite-element analysis and experiment in order to validate the proposed method. As a result, the main components of the torque ripple, the DC current ripple, and the vibration are reduced by 92.8%, 95.5%, and -18.0bB respectively. In addition, in comparison with the single pulse-wide current drive, the current RMS in three-phase SRM is increased by 27.8% as a sacrifice of the triple zero, while the current RMS in five-phase SRM is increased by only 2.4%.