Research on Electromagnetic Interference of Liquid Crystal Display Screen on Low-medium Speed Maglev Trains

Low-medium speed maglev trains might suffer from electromagnetic interference (EMI) during operation, which is specifically manifested as a blurred image on the liquid crystal display (LCD) screens of the passenger information system (PIS). In order to study the characteristics of the EMI, firstly, the working principle of PIS is analyzed in response to the fault phenomenon of the LCD screens. Possible interference sources are studied. Research results indicate that the leakage magnetic field generated by the transverse end effect of linear motors is the main interference source causing LCD screen faults. Secondly, the coupling mechanism of the EMI is analyzed. Results show that the transverse end effect can cause an increase in the ground potential of the LCD screen casing, resulting in a blurred image on the LCD screen. Finally, the EMI suppression method by suspending and grounding the LCD screen is proposed and its feasibility is verified. In this paper, we comprehensively study the EMI of LCD screens, which provides a theoretical basis for solving the tangible faults of maglev trains.