Electromechanical coupling modeling research on the piecewise-linear piezoelectric energy harvester

In this study, we propose an electromechanical coupling model to reduce the errors between the theoretical and experiment values of the pure mechanical model of the present piecewise-linear piezoelectric energy harvester. The amplitude-frequency response equation of voltage is provided on the basis of the electromechanical coupling model. The experiment results on the generating performance of the piecewise-linear piezoelectric energy harvester are obtained by processing the experimental unit and constructing the experiment platform. The comparison between the experimental and theoretical values of the pure mechanical model and the theoretical value of the electromechanical coupling model shows that the electromechanical coupling model can effectively reduce the errors between the experimental and theoretical values in comparison with the pure mechanical model. The relative errors of the voltage peak value decreased from 15.8% to 12.72% with an external excitation acceleration of 2 m/s2 and the impact distance of 1 mm. Accordingly, the relative errors of the frequency bandwidth reduced from 24.42% to 4.41%. Moreover, the investigations on different excitation accelerations and strike intervals show that the proposed electromechanical coupling model is more applicable to further research on the parameter optimization of the piecewise-linear piezoelectric energy harvester. © 2016, Editorial Department of Journal of HEU. All right reserved.