Gyroscope-based wind energy harvesting and piezoelectric-electromagnetic energy collection device for subway systems

This paper designs and investigates a gyroscopic-based subway wind energy harvesting and piezoelectric-electromagnetic hybrid energy conversion device (GB-PEH) for efficiently capturing the widely present yet underutilized piston wind energy in subway tunnels. The device employs a rotationally symmetric gyroscopic collector structure with low start-up wind speed characteristics, enabling response to airflow from any direction without requiring yaw mechanisms. Through the transmission mechanism, wind energy is converted into mechanical rotational motion, simultaneously driving piezoelectric generator sets and electromagnetic generator sets to achieve multi-mechanism coordinated conversion of wind energy. Experimental results demonstrate that within a wind speed range of 3–12 m/s, the turbine blades achieve rotational speeds of 280–1066 RPM. Under optimal configuration (terminal mass 2.4 g, 3 excitation magnets, load 200 kΩ), the piezoelectric unit outputs 11.64 mW of power, while the electromagnetic unit exhibits significantly increased output voltage with rising wind speeds. This device can provide stable power for low-power devices such as wireless sensor networks in subway tunnels, demonstrating excellent environmental adaptability and engineering application potential.