Parametric Sensitivity-Based Optimization of Additively Manufactured Permanent Magnets for Enhanced PMDC Motor Performance

A permanent magnet DC (PMDC) motor is among the most widely employed electrical machines due to its simple structure, high torque density, and cost-effectiveness. As energy efficiency, compact design, and operational reliability become increasingly critical in modern engineering systems, optimizing the design of PMDC motors has emerged as a significant area of interest. In particular, the configuration and material properties of permanent magnets strongly influence motor performance characteristics, including efficiency, torque production, and durability. Therefore, this paper presents a systematic approach that enhances the efficiency of PMDC motors by integrating detailed performance analysis with optimized design strategies. The contribution of magnetic effects to motor performance was analyzed in detail using the parameters of pole embrace, pole offset, and magnet thickness. A finite element method (FEM)-based numerical analysis is employed to perform a parametric sensitivity study of magnet geometry, aiming to reduce cogging torque and enhance electromagnetic torque and efficiency. The magnets of the 12 W, 2 pole, 1000 rpm PMDC motor were produced via additive manufacturing (AM). The fabricated samples were then tested and experimentally validated to assess their electromagnetic and performance characteristics. The results demonstrated an efficiency enhancement from 74.1% to 84.6% and a torque increase from 3.93 Nm to 4.93 Nm, while the cogging torque decreased from 0.0315 Nm to 0.009 Nm. The findings obtained from the FEM-based sensitivity analysis and electromagnetic field analyses validated the experimental design procedure of the proposed PMDC motor.