A current-flowing electromagnetic shunt damper for multi-mode vibration control of cantilever beams

Abstract

In this paper, a multi-mode electromagnetic shunt damper employing the current-flowing method is newly developed for the semi-active vibration control of flexible structures. The electromagnetic shunt damper, which is used for the electromagneto-mechanical coupling transduction between vibrating structures and the electrical shunt circuit, consists of a coil and a permanent magnet. The conducting coil is attached to the cantilever beams and the two ends of the coil are connected to the current-flowing shunt circuit for the reduction of vibration. For the analytical and experimental validation of the multi-mode electromagnetic shunt damper, the first two modes of the cantilever beam are semi-actively controlled. In light of the frequency responses, the vibration and damping characteristics of the flexible beams with the electromagnetic shunt damper are investigated with reference to changes in the circuit parameters. Also, the time responses of the integrated systems with an initial condition are experimentally examined for validation of the proposed damper. The effect of the magnetic intensity on the shunt damping is studied by varying the gap between the aluminum beam and the permanent magnet. The theoretical prediction of the frequency response of the electromagneto-mechanically coupled beams shows good agreement with the experimental results. The present results show that the current-flowing electromagnetic shunt damper can be successfully applied to reduce the multi-mode vibration of flexible structures.

Shunt Damping Vibration Control Technology: A Review

“…L and R are the total inductance and resistance vector of the electrical circuit. The governing equation of EMSD can be obtained by combing the structural and electrical equation together [34],…”

“…Cheng and Oh [34] extended the current flowing shunt damping from the piezo to the electromagnetics. An electromagnetic coil was bonded on the beam and a fixed permanent magnet was placed under the bottom of the coil.…”

“…Similar to PSD, when a shunt is connected across the terminals of the electromagnetic transducer, the kinetic energy of the vibrating structure can be dissipated through the coupling of the mechanical and electrical fields, the method is electromagnetic shunt damping [31], and a simplified model is shown in Figure 1b. After years of exploration, the parallel RLC shunt [32,33], the current flowing shunt [34], the synthetic shunt [35], the adaptive shunt [36] and the negative impedance shunt [37,38] have been studied to improve vibration control performance. Similar to the electromagnetic transducer, the magnetostrictive transducer consists of a rod of magnetic material and a coil surrounding it.…”

Vibration Suppression of a Cantilever Plate Using Magnetically Multimode Tuned Mass Dampers

“…Sodano et al [14][15][16] proposed the new concept of ECD device to attenuate the vibration of a cantilevered beam. Cheng and Oh [17,18] studied multimode vibration suppression using a permanent magnet and a coil with a shunt circuit for semiactive control.…”

Vibration suppression of a cantilever beam using magnetically tuned-mass-damper

“…Additionally, there are several studies [12][13][14][15][16][17][18][19][20][21][22] that have investigated the effects of magnetic fields on vibration in cantilever beams. Lee [13] studied the dynamic stability of conducting beam plates in a transverse magnetic field and demonstrated the existence of three regions of stability: damped stable oscillation, static asymptotic stability, and static divergence instability.…”