Affiliations: [a] School of Electronic & Machanical Engineering, Xidian University, Xi’an, Shaanxi 710071, China | [b] School of Astronautics, Northwestern Polytechnical University, Xi’an, Shaanxi 710072, China | [c] National Key Laboratory of Aerospace Flight Dynamics, Xi’an, Shaanxi 710072, China
Abstract: Magnetic suspension is a good choice for high precision manipulation. Several magnetic suspension systems have been proposed and shown to be effective for precision positioning. Most of these systems work with small air gaps and have a small movement range for suspended-load. Increasing the air gap will introduce uncertainty into the modeling and control of the system but is required for specific applications. The Large-Gap Magnetic Suspension and Balance System (LGMSBS) is a conceptual design for experiments which could be used to investigate the technology issues associated with magnetic suspension and accurate suspended-load control at large gaps. This paper investigates regulation and the control methods of magnetic suspension, and proposed a novel design comprised of a cylindrical element containing a permanent magnet, a planar electromagnet array, a position sensing system, a control system. In order to increase the uniformity of the magnetic field and have control over the distribution of the magnetic field, a new structure called planar electromagnet array is established. The magnetic properties are investigated through the mathematical modeling method. Since the magnetic suspension system is highly nonlinear and inherently unstable in operation, this paper deals with the problems of modeling and control strategy for the LGMSBS with 3D-movement control, and numerical simulations and experiments are provided to demonstrate the effectiveness and validity of our conclusions.
Keywords: Large-gap magnetic suspension and balance system, planar array of electromagnets, 3D-movement control
