In this study, the effects of critical geometric design parameters on the performance characteristics of Brushless Direct Current (BLDC) motors are investigated. Using the Finite Element Method (FEM), the effects of magnet thickness, pole embrace, and stator slot geometry were analyzed on a reference BLDC motor model selected for applications requiring high power density and efficiency. Parametric simulations conducted within the ANSYS Maxwell environment were optimized by taking into account magnetic saturation and air gap flux distribution. The analysis results demonstrate that motor performance and torque quality can be maximized without incurring additional material costs by determining the optimum saturation point for magnet thickness, selecting a pole embrace of 0.75, and modifying the stator slot geometry. Through this optimization, cogging torque was reduced by 94.01% compared to the reference model, thereby directly enhancing the acoustic comfort and mechanical lifespan of the motor. The limited variation of 1.67% in efficiency was successfully managed within a reasonable “Optimization Balance” favouring driving quality, attributed to the smoothness of torque transmission and the weight advantage gained from motor weight reduction.
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