Multiobjective Optimization of IPMSM With FSCW Applying Rotor Notch Design for Torque Performance Improvement

Fractional-slot concentrated-windings (FSCWs) interior permanent magnet (IPM) synchronous machines (IPMSMs) provide several advantages compared with other types of electric machines and have promising applications in electric vehicles (EVs). Minimizing the cogging torque and torque ripple of this type of motors is essential for improving output torque and driving stability. This article proposes a method for optimizing the torque performance of IPMSM with single-layer FSCW. At first, the theoretical analysis of cogging torque and torque ripple is conducted as the research basis for the optimization. The key point of this method is to describe the structure of the rotor notch as determined by seven design parameters. Then, the response surface methodology (RSM) is adopted to analyze the relationships between torque performance and design parameters. For the multiobjective optimization process, the seagull optimization algorithm (SOA) is introduced to obtain the optimal solution. After the optimization, the torque ripple of the motor achieves a significant reduction and the output torque is also improved. The advantages and reliability are compared and analyzed. Finally, a prototype is manufactured to verify the effectiveness of the proposed method.