Universal equivalent circuit model and verification of current source for triboelectric nanogenerator

In the field of energy harvesting and self-powered sensing, the universal equivalent circuit model of triboelectric nanogenerators (TENGs) is an important development tool for research and applications. Such a universal model of the current source is established to first order for the basic operating modes of a TENG, which provide the related theoretical models and electrical models used in simulation. The universal first-order equivalent circuit model demonstrates that the carrying capacity of a TENG separates into three regions of distinct output characteristics, namely, constant current, maximum power, and constant voltage. Moreover, employing electrometers, an electrometer and multimeters, and TENGs in series and parallel in successive experiments, we verify that the TENG can be considered a current source with a resistance of mega-ohms and a capacitance of nano-farads. Overall, our first-order model sets electrical standards for the internal circuit of the TENG and therefore provides theoretical guidance that lays the foundation for applications in high-performance supply and grid-connected power generation.