Enhanced energy harvesting using time-delayed feedback control from random rotational environment

Motivated by improving performance of a bi-stable vibration energy harvester (VEH) from the viewpoint control, time-delayed feedback control displacement and velocity are constructively proposed into an electromechanical coupled VEH mounted on rotational automobile tire, which is subject to colored noise periodic excitation. Using improved stochastic averaging procedure based energy-dependent frequency, expressions stationary probability density (SPD) signal-to-noise ratio (SNR) obtained analytically. Then, efficiency response resonance (SR) for delay-controlled explored in detail theoretically. Results show that both noise-induced SR delay-induced can occur. Time delay able not only enhance behavior but also weaken it. Furthermore, larger negative gain positive more beneficial VEH. Interesting finding optimal combination time maximizing harvested performance, such as harvest power, output voltage power conversion efficiency, almost perfectly consistent with SNR. Compared uncontrolled VEH, achieve certain desirable optimization harvesting choosing appropriate delays gains.