Nonlinear Hybrid Piezoelectric and Electromagnetic Energy Harvesting Driven by Colored Excitation

Abstract

It is well known that when excited by a stochastic base acceleration, the power absorbed by a nonlinear Duffing-type piezoelectric (PE) or electromagnetic (EM) energy harvester might not be increased effectively compared to a linear one. When intentionally introducing nonlinear magnetic forces into a doubly-clamped hybrid PE and EM energy harvester subjected to narrow-band (colored) excitation however, the power output could be improved to a much higher value. Also, in comparison with the typical nonlinear PE or EM generator, the influence of load and excitation parameters on the performance of a nonlinear hybrid energy harvester under colored excitation has been proven rather different as well. These results are derived analytically by solving the Fokker-Planck (FP) equation, and numerically by Monte Carlo (MC) simulations for validation. Besides, for a nonlinear hybrid configuration excited by colored noise approaching white Gaussian excitation, theoretical output characteristics are discussed and compared with results from a reported theory for white Gaussian excited case, which again verifies the feasibility of the theoretical analysis.