In-Out Cylindrical Triboelectric Nanogenerators Based Energy Harvester

The arising need for self-powered devices have driven the research towards new energy harvesting techniques, especially the mechanical energy. Triboelectric nanogenerators (TENGs) are considered a very promising technique for harvesting mechanical energy. However, most of the studies in the literature have been focusing on rectangular TENGs with with a scarce research in cylindrical configurations. In this paper, a novel In-Out cylindrical TENG mode is proposed to serve as a potential candidate for different applications. A FEM model is constructed using COMSOL-Multiphysics to characterize the device intrinsic properties such as open circuit voltage $V_{oc}(x)$ and short circuit charges $Q_{sc}(x)$. Furthermore, an analytical model is developed to obtain a closed form $(V-Q-x)$ relation with its accuracy validated against the FEM model. The results show an excellent agreement with an average error of 5.2% due to FEM limitations, which was a motivation for establishing a Verilog-A model as a circuit element to describe the mode’s behavior under different loading conditions and explore its ability to be integrated into different applications.