Electrostatic energy harvesting device with dual resonant structure for wideband random vibration sources at low frequency

In this paper, we present design and test of a broadbandelectrostaticenergy harvester with a dualresonant structure, which consists of two cantilever-mass subsystems each with a mass attached at the free edge of a cantilever. Comparing to traditionaldevices with singleresonant frequency, the proposeddevice with dualresonant structure canresonate at two frequencies. Furthermore, when one of the cantilever-masses is oscillating atresonance, the vibration amplitude is large enough to make it collide with the other mass, which provides strong mechanical coupling between the two subsystems. Therefore, thisdevice can harvest a decent power output from vibration sources at a broad frequency range. During the measurement, continuous power output up to 6.2-9.8μW can be achieved under external vibration amplitude of 9.3 m/s2 at a frequency range from 36.3 Hz to 48.3 Hz, which means the bandwidth of thedevice is about 30% of the central frequency. The broad bandwidth of thedevice provides a promising application forenergy harvesting from the scenarios withrandom vibration sources. The experimental results indicate that with the dualresonant structure, the vibration-to-electricityenergy conversion efficiency can be improved by 97% when an externalrandom vibration with a low frequency filter is applied.

Source: Review of Scientific Instruments - December 5, 2016 Category: Physics Authors: Yulong Zhang, Tianyang Wang, Ai Zhang, Zhuoteng Peng, Dan Luo, Rui Chen and Fei Wang Source Type: research