Realistic control considerations for electromagnetically levitated urban transit vehicles

This paper discusses realistic control considerations of suspension dynamics and vehicle/guideway interaction for electro-magnetically-levitated urban transit vehicles in the context of revenue applications. The emphasis is on safety, reliability and maintainability rather than performance. An example urban transit system is described and the following considerations of dynamics and control are examined: stability, magnet force requirements, magnet airgap requirements, vehicle ride, and component failures. It is shown that it is a formidable problem to ensure suspension stability under all conditions; that operation on curves is a critical magnet and control system design case; that operation of the magnets in the non-linear regime is unavoidable and that component failures will be a major problem. However, good vehicle ride is to be expected. It is concluded that magnetic lévitation suspension technology requires substantial development effort before it can be considered suitable for revenue operation.