Comparative study on guidance force characteristics of independent double-circuit asymmetric null-flux coil for guidance force enhancement

The Electrodynamic Suspension (EDS) systems are gaining significant attention as next-generation high-speed transportation technology due to their inherent self-stabilizing characteristics and superior lift-to-drag ratios. Conventional figure-eight null-flux coils used in EDS systems provide the advantage of simultaneously realizing levitation and guidance within a single structure. However, due to their structural mechanism, the levitation and guidance forces are strongly coupled, which limits the independent enhancement of guidance performance. To address the limitations of conventional cross-connected null-flux coils, this study proposes an independent inner-outer double-circuit asymmetric null-flux coil structure. The guidance characteristics of the proposed structure were quantitatively evaluated and compared with those of the conventional symmetric model using three-dimensional Finite Element Method (3D FEM) analysis. The simulation results demonstrate that the proposed asymmetric coil achieves approximately 6.47% improvement in guidance force at a 50 mm lateral displacement compared to the conventional model (20.08 kN), indicating its strong potential to enhance the driving stability of EDS systems.