Linear freestanding electret generator for harvesting swinging motion energy: Optimization and experiment. (November 2019)

• Record Type: Journal Article
• Authors: Wang, Shiwen; Bi, Mingzhao; Cao, Zeyuan; Ye, Xiongying
• Is Part Of: Nano energy. Volume 65(2019)
• Publication Date: 2019-11
• Subjects: Energy harvesting -- Electret -- Linear generator -- Swinging motion -- Optimization; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2019.104013
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: Nowadays, harvesting mechanical energy from body motion for powering wearable electronics has gained great attention. Swinging motion is a common motion in the human body. Herein, we demonstrate a linear grating-structured freestanding electret generator with the electrodes as the slider for harvesting arm swinging energy. The analytical solutions of the outputs of the generator under uniformly accelerated motion are obtained from its theoretical model. It is verified that the formula of average power under uniform motion can be used to estimate the matched load resistance and optimize the parameters of the generator under uniformly accelerated motion, and the optimized results are independent of the motion mode. The generator gets the maximum power when the effective length of the slider is half that of the stator and can double the output power compared with conventional generators with electrodes as the stator. We optimized the generator by taking the fringe effect of the electric field and the parasitic capacitance into consideration, and the optimized generator generates tens of microwatts of power from arm swinging. Graphical abstract: Image 1 Highlights: A linear freestanding electret generator with electrodes as the rotor doubles the output power than conventional ones. Formula of average power for uniform motion is verified to be used to optimize generator parameters for accelerated motion. The optimization of the generator considering fringe effect and parasitic capacitance simultaneously is conducted.