Simultaneous seismic mitigation and harvesting performance of an electromagnetic energy-harvesting nonlinear energy sink

A novel electromagnetic energy-harvesting nonlinear energy sink (EH-NES) is proposed for simultaneous vibration mitigation and energy harvesting. Considering parasitic effects, shaking table tests are conducted to examine the device performance, followed by parameter identification. Numerical models are validated in terms of both mechanical and electrical responses, followed by parametric studies to quantify the impact of critical parameters on the dual-functional performance. Moreover, seismic robustness analyses evaluate the potential of the EH-NES for synchronized vibration mitigation and energy harvesting across various seismic scenarios. Experimental results indicate that the EH-NES reduces structural displacement by over 20%, while harvesting a peak voltage and power of 376 mV and 83.22 mW, respectively, at a peak ground acceleration (PGA) of 0.25 g . Parametric studies identify the optimal EH-NES mass ratio between 7.5% and 10%. The EH-NES performance degrades markedly with increasing inertance ratio, whereas an inertance ratio below 10% is an acceptable limit. In addition, increasing load resistance enhances vibration mitigation by 5%-8%, whereas output voltage approaches saturation as harvested power continuously decreases. Seismic robustness analyses reveal that the EH-NES performance is highly sensitive to PGAs, exhibiting a marked improvement with increasing seismic intensity. Across diverse seismic scenarios with an Arias intensity of 1 m/s, the EH-NES yields an average RMS reduction ratio, peak output voltage, and peak power of 22.44%, 340.9 mV, and 149.66 mW, respectively. These findings confirm the spectral robustness of the EH-NES for simultaneous vibration mitigation and energy harvesting under seismic excitations.