Fuzzy Control of Nonlinear Electromagnetic Suspension Systems

Abstract

Owing to its environmental, commercial and technological attractions, the electromagnetic suspension system [91] has been widely adopted in many real applications. Systems, such as that in high-speed maglev passenger trains [231, 105], levitation of wind tunnel models, levitation of molten metal in induction furnaces, vibration isolation and frictionless bearings, are mostly based on electromagnetic suspension systems. Therefore, in this view, electromagnetic suspension systems can be regarded as repulsive system or attractive system which is based on the source of electromagnetic levitation forces. Due to the involvement of magnetic force, these kind of systems are mostly modeled by highly nonlinear differential equations and usually unstable, thus making it difficult when considering controller design. Over the past few years, various controller design schemes have been considered to manipulate electromagnetic suspension systems, see for example, [38, 84, 103, 182, 183, 191, 204].