Optimal Design of Gap Sensor for High-Speed Maglev Train

Abstract

The gap sensor plays an important role in high-speed maglev train which is able to measure the variation of trains’ suspension gap. The magnetic fields distribution is different clearly when the sensor is opposite to different position in a tooth-groove period of stator railway. The fluctuation of equivalent inductance leads to the slot-effect. The slot-effect is an important factor affecting the stability of the high-speed maglev train suspension control system. The distribution of magnetic field intensity of the flat rectangular coil in different gaps and positions is analysed, and the mechanism of slot-effect is revealed. A new coil is proposed in this paper and this optimized coil can create a smaller slot error than the flat rectangle coil. The simulation results show that the slot error of optimized coil is always less than the error of original coil in any gap distance. The slot error is reduced by half at the working air gap from 8mm to12mm. The slot error of the optimized coil reaches a maximum at 2mm and reaches its minimum at the rated suspension gap 10mm.