Conceptualization of an electromagnetic automatic transmission via mathematical modeling for vehicle drive-train applications

Abstract

This research presents a comprehensive investigation of electromagnetic gearing systems for automotive powertrain applications, evaluating their potential to replace conventional mechanical automatic transmissions. Three fundamental electromagnetic architectures - Variable Volume Approach (VVA), Fixed Volume Approach (FVA or separate drive of individually magnetized ring), and Fixed Volume Approach Pole-based (FVAP) - are analyzed through five distinct design configurations employing harmonic and geometric sequencing. A rigorous analytical framework is developed to assess electromagnetic coupling dynamics, evaluating critical parameters including energy density, volumetric constraints, magnetic flux distribution, and torque transmission characteristics. Performance assessment using Gray Relational Analysis (GRA) reveals the FVAP configuration as superior (GRA grade: 0.95), demonstrating optimal torque density (3.01 MNm/m³ FEM) and specific torque (320-344 Nm/kg). Comparative analysis shows electromagnetic systems achieve 20–22 % higher specific torque than optimal range of mechanical planetary gears about (267–282 Nm/kg), though their volumetric torque density remains below conventional systems (3–5 MNm/m³). The study identifies key performance trade-offs: VVAH (0.72) and VVAG (0.68) deliver competitive torque but exhibit elevated flux leakage, while FVAG (0.58) and FVAH (0.64) show balanced but limited performance. The research highlights electromagnetic gearing as a transformative technology for weight-sensitive applications, offering inherent advantages including contactless operation, adaptive torque control, and reduced maintenance. Findings suggest these systems are particularly suitable for electric and hybrid vehicle architectures where power density and efficiency are critical. Future development pathways focus on advanced magnetic materials and superconducting implementations to bridge the volumetric performance gap. This work provides a foundational framework for next-generation transmission systems, establishing quantitative performance benchmarks and design guidelines for electromagnetic gearing in automotive applications.