Experimental study of a self-powered and sensing MR-damper-based vibration controlsystem

Abstract

The paper deals with a semi-active vibration control system based on a magnetorheological(MR) damper. The study outlines the model and the structure of the system, and describesits experimental investigation. The conceptual design of this system involves harvestingenergy from structural vibrations using an energy extractor based on an electromagnetictransduction mechanism (Faraday’s law). The system consists of an electromagneticinduction device (EMI) prototype and an MR damper of RD-1005 series manufactured byLord Corporation. The energy extracted is applied to control the damping characteristics ofthe MR damper.The model of the system was used to prove that the proposed vibration control system isfeasible. The system was realized in the semi-active control strategy with energy recoveryand examined through experiments in the cases where the control coil of the MR damperwas voltage-supplied directly from the EMI or voltage-supplied via the rectifier, or suppliedwith a current control system with two feedback loops. The external loop used thesky-hook algorithm whilst the internal loop used the algorithm switching the photorelay, atthe output from the rectifier. Experimental results of the proposed vibrationcontrol system were compared with those obtained for the passive system (MRdamper is off-state) and for the system with an external power source (conventionalsystem) when the control coil of the MR damper was supplied by a DC powersupply and analogue voltage amplifier or a DC power supply and a photorelay.It was demonstrated that the system is able to power-supply the MR damper and canadjust itself to structural vibrations. It was also found that, since the signal of inducedvoltage from the EMI agrees well with that of the relative velocity signal across thedamper, the device can act as a ‘velocity-sign’ sensor.