Enhancing the performance of Bi-stable Energy Harvester using Chaos control

Chaotic behavior in bi-stable energy harvesters severely reduces the harvested energy. Besides reducing the energy extracted, this behavior makes the interface circuits' design and production complicated and costly. In this study, chaos control in bi-stable energy harvesters has been investigated. A controller with delayed feedback control has been added to the bi-stable energy harvester to eliminate chaos. Then, the stability range of the control gain is calculated by using the Poincare section. Also, the effect of the main harvesting parameters on the control system stability has been studied. The controlled bi-stable energy harvester's numerical simulation response shows that chaotic behavior is well converted to periodic behavior by the controller. The energy balance diagram shows that the controlled harvester can recover the consumed energy in the actuator in a relatively short time. A bi-stable energy harvester with a chaotic controller has improved in energy and output power compared to a bi-stable harvester without a controller. Changing the control gain, the cross-time in which the harvested energy of the controlled harvester passes the harvested energy by the uncontrolled one is optimized to its minimum possible amount.