Optimized Design of Axial Flux Permanent Magnet Motors with Variable Air Gap Function

To enhance motor efficiency, reduce the complexity of optimization algorithms, and lower the cost of three-dimensional finite element analysis, this study focuses on minimizing cogging torque, maximizing output torque, and improving back electromotive force (EMF) as optimization objectives. A 20-pole, 24-slot axial-flux permanent magnet motor with dual stators and a single rotor was analyzed using the parameter scanning method to evaluate the impact of key structural parameters on motor performance. The pole arc coefficient, permanent magnet thickness, and air gap length were identified as critical factors. A functional permanent magnet design was proposed, maintaining the same volume as the original permanent magnet. Compared to conventional permanent magnets, this design reduces cogging torque and improves the waveform of back EMF, validating the rationality of the functional permanent magnet.