Optimization of Cogging Torque in Radial Flux Brushless DC Motor Using a Novel Stator Side Approach

Cogging torque, recognized as a predominant issue in permanent magnet motors, is the primary contributor to torque fluctuations, thereby inducing adverse effects such as audible noise and motor vibration. However, addressing cogging torque is feasible through tailored design modifications within the permanent magnet motor. This study investigates cogging torque in a radial-flux surface-mounted permanent magnet brushless DC (BLDC) motor using stator side design modification techniques. This proposed technique involves strategic alterations to the tooth edge inset width, specifically optimized for a BLDC motor rated at 1 kW, 48 V, and 510 rpm for electrical vehicle application. The reduction in cogging torque was meticulously examined utilizing electromagnetic analysis. The simulation results revealed promising outcomes, demonstrating a significant decrease in cogging torque while maintaining minimal deviation in both motor torque and back-emf. These findings underscore the effectiveness of these design modifications in mitigating cogging torque without adversely affecting other critical aspects of motor performance.