Versatile Behaviors of Electromagnetic Shunt Damper With a Negative Impedance Converter

An electromagnetic shunt damper (EMSD) refers to the electromagnetic device connected to a specially designed shunt circuit that suppresses structural vibration. The analogy between mechanical and electrical systems offers the theoretical possibility of imitating various mechanical dampers using EMSDs. However, the inherent resistance of the whole circuit unfavorably affects the EMSD performance, including the analogous relationship. This study proposes a novel passive solution to address this practical limitation by using a negative impedance converter with voltage inversion (VNIC) to partially cancel the inherent resistance of shunt circuits. The benefit of the VNIC is revealed through theoretical and experimental studies. With the aid of a VNIC, a single electromagnetic device can mimic the versatile behaviors of different types of conventional dampers, such as viscous fluid, viscoelastic, inerter, and tuned inerter dampers, by conveniently adjusting the designs and parameters of shunt circuits. To the best of the authors' knowledge, the versatility of EMSDs presented in this paper has not been experimentally illustrated in the literature.