LAUSR

High torque ripple is inherent in switched reluctance motors (SRMs) because of the motor's doubly salient structure and highly non-uniform torque and magnetisation characteristics. Direct torque control (DTC) for SRM is one of the torque ripple reduction strategies which gets wide attention for its simpleness and effectiveness. In this study, aiming at the torque ripple phenomenon of DTC for SRM, a novel method for torque-ripple reduction is proposed. With the new methods, sector zones were redivided into 9 and 12 sector zones based on six sector zones and new control rules were adopted. Consequently, the proposed methods make the selection of voltage vector more precise. A 12/8-pole three-phase SRM drive system was designed to verify the effectiveness of the proposed new methods. The results verified that the improved DTC algorithms with 9 and 12 sector zones could indeed minimise the torque ripple to a great extent.