The overhead transmission lines, regarded as the blood vessels in human body, play essential roles in energy transport and distribution as well as future "carbon emission reaching the peak and eventually carbon neutralization". On the demands of high-voltage delivery, the transmission lines are normally designed in extended span length and elevated height with wide cross-section, which are vulnerable to the aeolian vibration produced by Von Karman vortex. [5][6] This phenomenon will push the line into an up-and-down motion in vertical direction, causing fatigues, broken strands, even broken wires in transmission lines, seriously threatening the safety and reliability of power grid. [7][8][9] Thus, the aeolian vibration sensors are necessarily provided to monitor the state of transmission lines through the vibration amplitude and frequency. The fiberoptic and the piezoelectric-based sensors as the most common aeolian vibrations sensors have been applied for online-monitoring with unignorable limitations. [10][11][12][13][14] The major result deviations caused by the slight fluctuation of the light source as well as the high cost of fiber optic material restrict the further large-scale installation of the fiber-optic sensors. And the piezoelectric-based ones are also troubled with the serious nonlinear relational errors between the material Overhead transmission lines are vulnerable to aeolian vibrations that threaten the operation of the power grid. A triboelectric nanogenerator (TENG) based self-powered system offers a desirable way for vibration onlinemonitoring with potential for large-scale deployment. In this work, a selfpowered sensor network constructed by active vibration sensor (AVS) units with a spring-mass based TENG (S-TENG) is reported for effective energy harvesting and broadband vibration sensing. The basic TENG with structural parameters is first discussed from the aspects of efficiency and response characteristics, then the spring constant and mass weight are also adjusted for S-TENGs with different optimal operation regions, thus the overall vibration amplitude and frequency response are further enhanced by the mutual compensation of S-TENGs with a weight allocation strategy. Furthermore, the S-TENGs are combined with external circuits to compose the AVS units, which are deployed in a distributed manner on a simulated transmission line to demonstrate a self-powered wireless warning system and an aeolian vibration mapping system, enabling abnormal vibration warnings and vibration distribution monitoring over the whole line. This work represents a novel strategy for utilizing TENG technology for transmission line aeolian vibration monitoring and provides valuable guidance for further sensor network construction and power grid visualization.

An agglomeration phenomenon characterized by nanoparticle dispersion is a decisive factor that reflects the degree of the maintained overall performance of nanofluids and other nanocomposites. However, the quantitative characterization and non-destructive measurement for nanofluid dispersion (NFD) still remain challenged. Herein, an in situ NFD measurement system based on a variable frequency liquid-solid triboelectric nanogenerator (VFLS-TENG) is developed. This work utilizes VFLS-TENG as a passive probe and proposes an equivalent capacitance circuit model for detecting NFD based on the electric double layer model at liquid-solid interfaces. In the circuit model, a quantitative calculation process for both particle size and spacing is introduced through parameter identification using the Quantum Genetic and Levenberg-Marquardt hybrid algorithm, and parameter separation using the Runge-Kutta algorithm. The results demonstrates a good agreement with the traditional methods, among which the measured particle size is more accurate than the hydrodynamic diameter of dynamic light scattering by 28.6% with a high sensitivity of 1667 nm nF −1 . The proposed method is capable of measuring the effective charge on the nanoparticle surface in situ, and simultaneously obtaining the particle size and spacing for the online monitoring NFD, thus further facilitating the controllable preparation during the nano-composites modification, and quantitative optimization of nanofluid design performance.

Abnormal vibration is a direct response to the mechanical defects of electrical equipment, and requires reliable vibration sensing for health condition evaluation in the associated system. The triboelectric nanogenerator (TENG) triggered by random vibration to generate electrical energy/signal while giving feedback on the vibration state, paving a promising way towards self‐powered sensors. Here, an all‐in‐one sensing system configured with a vibration sensor demonstrates instantaneous discharge boosted TENG and IR wireless communication for vibration state online monitoring. The sandwich‐structured TENG combined with mechanical switches can release the co‐accumulated charges from dual triboelectric layers to yield giant instantaneous output power of 616 W, which is 106 times higher than that of the continuous discharge. Moreover, an IR LED as a transmitter driven by the TENG can form an all‐in‐one vibration sensor enabling wireless communication, where the sensor can be further integrated with repeaters and phones to establish a wireless vibration online monitoring system for vibration state visualization. This work presents a novel idea to implement high‐power TENG with IR communication integration for in situ vibration online monitoring. Such a strategy is potentially available for distributed sensor construction towards abnormal signal monitoring that reflects the operating state of equipment.

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