Tractive Force Estimation for Hybrid PM-Electromagnetic Suspension System Maglev Train Prototype

Abstract

This paper presents a tractive force estimation method for a hybrid PM-electromagnetic suspension system within a maglev train prototype. The main structure of the levitation system consisted of levitation cores, levitation coils, and inserted permanent magnets installed on both sides of the train. The key variable affecting tractive force were magnetic flux density from the levitation coils and permanent magnets, the cross section of the levitation cores, and the permeability of air gaps. To estimate traction force, the magnetic circuits of the levitation systems were first analyzed accounting for air gap variation as a results of total train weight, as tractive force across air gaps would need to balance the weight of the train. The simulations were carried out using a finite element analysis (FEA) program with constant air gaps of 10mm, at which permanent magnets were installed. The simulation and estimation results were compared to verify the accuracy of the proposed estimation method.