Enhancement of a dynamic vibration absorber by means of an electromagnetic shunt

Abstract

In this study, we address the reduction of structural vibrations by means of an electromagnetic shunt damper (EMSD) combined with a mechanical dynamic vibration absorber (DVA). Two architectures, that differs in the placement of the EMSD with respect to the DVA, are tested, showing that one of them enhances the vibration control. In parallel, three shunt architecture are tested: a resistive shunt, a resonant conservative shunt and a resonant dissipative shunt. Optimal values of the EMSD and DVA parameters are obtained; then, the performances of all architecture, according to relevant criteria, are estimated and compared to a single DVA or a single EMSD. The case of a conservative DVA, that creates an anti-resonance, is particularly targeted. It is shown that the performances rely on two free parameters only: the mass ratio for the DVA and the electromagnetic coupling factor for the EMSD, thus giving generic abacuses that can be applied to any practical cases. Finally, experiments are proposed and a good agreement with the theoretical results is obtained, thus validating them.

Tunable electromagnetic resonant shunt using pulse-width modulation

“…The theoretical optimal tuning of the parameters is, with a one mode model (N = 1 in Eq. ( 16), see [9] and reference therein):…”

“…Equivalent damping properties can be obtained using electromechanical shunts, in which a transducer converts the vibratory energy of the host structure into electrical energy in a dedicated electronic circuit, designed to dissipate it and/or to counteract the structure's vibrations. Depending on the physics of the transducer, piezoelectric or electromagnetic shunts have been proposed in the pioneering works [6,7], and have been addressed in a huge number of contribution since (see [8,9] and reference therein).…”

“…(i) If it has a broadband frequency content, one is often interested in attenuating as much as possible one or several resonances of the host structure. Depending on the figure of merit of the absorber (the mass ratio for the DVA; the electromechanical coupling factor for the shunts) and the damping ratio of the considered mechanical mode, substantial vibration reduction can be obtained on a single resonance [5,9,10,11]. Several resonances can also be attenuated with more complex circuits [12].…”

“…Several resonances can also be attenuated with more complex circuits [12]. (i) For a tonal excitation signal, DVAs and resonant shunts, damped as less as possible, can be efficiently used to almost cancel the vibration energy by creating an antiresonance at the absorber natural frequency [9]. In those two cases of broadband or tonal excitation signal, the fine tuning of the absorber natural frequency, either on a particular host structure resonance or on the excitation frequency, is mandatory.…”

Hybrid skyhook mass damper

“…It can easily be realized using an AMD and a direct velocity feedback [19][20][21], but the system is not hyperstable and the fail-safe behavior is not certain as the actuator is not tuned on the main resonance as for a TMD. Recently, [22] proposed to combine a dynamic vibration absorber (DVA) with an electromagnetic shunt damper, showing that this association allows damping the resonances while keeping the strict antiresonance created by the DVA. A semi-active controller can also be a good candidate for hybridization [23], to reduce the energy demand again.…”