Abstract: Superconducting electrodynamic suspension (EDS) trains achieve levitation and guidance through electromagnetic forces generated between onboard superconducting coils and ground 8-shaped null-flux coils. By utilizing the induced magnetic field of track coils, non-contact electromagnetic dampers (EMDs) and electromagnetic shunt dampers (EMSDs) to effectively suppress vibrations. This article establishes an electromechanical coupled dynamics model incorporating electromagnetic dampers, optimizes the electromagnetic parameters, and validates both the modeling approach and optimization results. First, coupling between mechanical and electromagnetic systems is modeled by integrating dynamic electrical circuits and motion equations. The electromagnetic model's accuracy is validated through comparisons with finite element simulations and experimental results. Subsequently, electromechanical coupling analysis between the suspension bogie and EMD/EMSD is conducted. Based on fixed-point theory, resistance, inductance, and capacitance parameters are optimized to achieve balanced vibration reduction across a wide frequency range. Finally, dynamic analyses under various external excitations are carried out using the optimized damper design. Results indicate effective suppression of suspension bogie vibrations in both free vibrations and random vibrations due to track irregularity excitations, with superior performance of the EMSD arising from resonance frequency matching. This study proposes an electromechanical modeling and optimization approach for passive EMSD for EDS train systems, providing significant scientific value and promising engineering application prospects.