A Survey of the Literature Relating to Electromagnetic Suspension Systems

摘要

The material is grouped into five headings. The first two relate to magnetic systems. Under this heading, the object is 'suspended' by forces that are principally magnetic. These include the attractive 'magnetic pull' on ferromagnetic objects and the repelling forces encountered in eddy current repulsion and cryogenic suspension systems. The term 'active direction' is used to indicate that direction in which the force is served to maintain stability. The third and fourth groups relate to electrostatic systems in which the forces are principally due to electric fields. Of the two systems, magnetic and electrostatic, the theory for the electrostatic system is both straightforward and complete (as far as the support forces are concerned). However, the magnetic system has been the most versatile laboratory tool. Both of these factors team up to make the literature on the electrostatic systems very sparse. Until the recent interest in the electrostatic gyroscope, little was done with electrostatic forces except for electrostatic generators. Now considerable effort is directed toward increasing the upper limit of the electric field strength before breakdown occurs. The fifth group is a wide selection of topics which are included not necessarily because they pertain directly to suspension systems, but because they seem to be relevant to other aspects of the over-all program -- only a part of which is the suspension of rotating machinery. (Author)