Coupling Mechanism between Electromagnetic Induction Generator and Triboelectric Nanogenerator toward Effective Ocean Energy Harvesting

Triboelectric nanogenerator (TENG), based on the coupling of triboelectric and electrostatic effects, provides an approach for efficiently harvesting blue energy, due to its high-voltage, low cost, and lightweight. Recently, most of the ocean energy harvesting devices based on TENG only rely on one mode. However, the output current of TENG is 3 sim 4orders of magnitude smaller than that generated by electromagnetic induction generator (EMG). Herein, the hybrid triboelectric-electromagnetic nanogenerator (HTEMG) based on the nodding duck structure multi-track freestanding TENG (NDM-FTENG) is proposed for ocean wave energy harvesting to improve the output performance of NDM-FTENG. The feasibility of HTEMG system is analyzed through theoretical modeling and simulation under the same frequency, and the output performance of the EMG and TENG coupling in series or parallel agrees well with the experimental results. Due to the large difference of open-circuit voltage (V {oc})and short-circuit current (I {sc})between EMG and TENG, the output performance including Voc and Isc of the HTEMG decreases in the coupling process. The power management circuit of the generated high-voltage for practical low-voltage applications is designed by Multisim software, which improves the coupling output power of EMG and TENG. Moreover, the HTEMG coupling in parallel shows superior output potential and higher power generation capacity compared to the HTEMGs connected in series and individual TENG, which is a 3-fold enhancement compared to that of the individual TENG for energy storage by charging capacitor 1 mu Fwithin 100s. This work not only renders a theoretical basis for coupling the EMG and TENG toward effective blue energy harvesting, but also presents great prospects for enabling self-powered smart ocean systems without the need of any power-consuming control electronic circuits.