A dual-mode self-powered wind energy harvesting system for urban bridges with AI-enhanced wind speed monitoring

Bridges act as crucial components within urban transportation networks, which requires the safe and stable operation of sophisticated self-powered sensing systems. Traditional technologies encounter challenges such as low efficiency in micro-energy harvesting and difficulty initiating at low wind speeds. To overcome these challenges, this study introduces a dual-mode self-powered wind energy harvesting system specifically designed for urban bridge applications. This innovative system utilizes a dual-impeller drive mechanism and combines two primary power generation units: a double-deck Halbach electromagnetic generator with a coaxially counter-rotating coil disk and a rolling ellipsoidal triboelectric nanogenerator. The double-deck Halbach array aligns the potent magnetic surfaces of the magnet discs towards the central coil disc, thereby optimizing the electromagnetic conversion of ambient wind energy. The rolling ellipsoidal triboelectric nanogenerator captures fluctuations in wind speed through a rolling contact-separation mechanism. The experiment results of wind tunnel tests showed that the dual-mode wind energy harvesting system can obtain a maximum output power of 110.6 mW at 12 m/s. When wind speed is 5 m/s, the system can charge a 0.3 F capacitor to 3V in 56 s. Additionally, a predictive model of the wind field, developed using a deep learning algorithm based on gated recurrent units, achieves a wind speed prediction accuracy of 98.46%. The field test on bridge demonstrates that the device supports self-powered operation and provides early warnings of strong wind hazards through its wind speed monitoring capabilities. Accordingly, a comprehensive “self-powering and self-sensing” solution is offered for Internet of Things-enabled intelligent elevated bridges.