Enhancing electrical and magnetic performance of carbon fiber polymer composites with Fe₃Si for lightweight, high-efficiency synchronous reluctance motor rotors

The demand for lightweight and energy-efficient electric motors in electric vehicles, aerospace, and industrial systems has driven the exploration of alternative rotor materials. This study introduces a novel Fe₃Si-enhanced carbon fiber-reinforced polymer (CFRP) composite rotor designed for high-speed synchronous reluctance motor (SynRM) applications. Soft magnetic Fe₃Si microparticles were uniformly integrated into the CFRP matrix using a hand lay-up method with dry particle deposition, resulting in enhanced magnetic permeability and reduced electrical conductivity while preserving structural integrity. The optimized composite rotor core achieved a weight and rotational inertia reduction of 38.12% compared to conventional electrical steel (ES) rotors core, with a reduced density of 4857.95 kg/m³. Furthermore, by strategically reducing the rotor magnetic pole arc angle from 145° to 130°, the lower intrinsic permeability of the composite was effectively compensated. Electromagnetic simulations revealed that the optimized Fe 3 Si-enhanced CFRP composite rotor achieves a peak efficiency of 94.0%, closely matching the benchmark ES rotor (95.4%), while suppressing eddy current and core heating due to the discontinuous conductive network of the polymer matrix. These results highlight the potential of Fe 3 Si-CFRP composites as lightweight, high-efficiency core materials for next-generation electric machinery.