Active electromagnetic damping of laterally vibrating ferromagnetic cantilever beam
Danjel Voncina2007, Mechatronics
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Abstract
In linear mechanical systems, the vibration of mechanical structures depends upon the boundary conditions, the mode of excitation and the dissipative or damping capacities of the system itself. The latter are the result of passive residual and structural friction. In the cases where passive damping of mechanical structures becomes inadequate, dynamic reactivity of the structure may be influenced by controlled active damping which is particularly suitable for non-linear systems where the structure response and excitation are directly interconnected. The present paper deals with active electromagnetic damping of lateral vibration of a clamped steel cantilever. The electromagnetic system consists of a switching current amplifier and a pair of electromagnets, which are mounted laterally at a right angle to the plane of the steel cantilever. A simulation model of control system has been produced and confirmed by experiments. Control algorithm is simple, efficient and ensures stability in operation.
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