Research on anti-adsorption control in hybrid maglev system with permanents and electromagnets

Anti-adsorption control in hybrid maglev system with permanents and electromagnets was researched in this paper. The mathematical model of single-point suspension system was established, and proportional-integral-differential controller aimed to fixed-current suspension was designed firstly. In order to avoid hybrid magnet adsorbing the guideway, variation law of gap was used to estimate whether adsorption would occur in the future. The optimal negative current, which should be adopted when adsorption estimation was true, was calculated according to the formula of levitation force. This kind of anti-adsorption control method was applied in a practical hybrid maglev system, and its effect was proved based on appropriate area of state variables. The conclusion was drawn that suspension magnet was prevented from adsorbing guideway effectively under this control when suspension control system could work normally.