Scaling laws for electrodynamic suspension in high‐speedtransportation

Abstract

Electrodynamic suspension (EDS) relies on the repulsive force created by eddy currents in a stationary conductive body (rail) and a magnetic field generated by an excitation system on a moving vehicle (pod). The excitation system in this paper consists of permanent magnets in a Hallbach array. EDS generates lift forces that levitate the pod reliably at high speeds of the vehicle since no mechanical suspension is required. Therefore, it gains interest for high-speed transportation applications such as the Hyperloop project, driven by the Space Exploration Technologies Corporation (SpaceX). Electrodynamic fields and forces have been analysed in detail in the literature; however, the sophistication and/or limited applicability of analytical approaches or the computational burden of FEM/numerical methods render those impractical for the initial design of EDS systems. Therefore, power and loss scaling laws for EDS systems are derived in this study. A 3D simulation for a design example shows that the scaling law is within 10% deviation. Finally, the drag coefficient of EDS systems is compared with other forms of commercial high-speed ground and air transportation systems. A pod with EDS running in vacuum has the potential of decreasing energy consumption significantly above the cruising speeds of modern subsonic airliners.