Research on Wireless Power Transmission Technology for Underground Deformation 3-D Measurement Device

Monitoring underground displacement is crucial for landslide disaster early warning. In this work, an innovative approach is proposed to use the measurement coil in the device as a wireless power transmission (WPT) coil at the same time. Through the magnetic coupling resonance method, WPT between the sensing units is realized, thus solving the problems of inconvenient transportation and vulnerability to lightning damage caused by wired power transmission in the original device. The transmission efficiency of the system is studied based on the coil intrinsic model topology and the series–series (SS) topology transmission circuit. The results show that by connecting appropriate compensation capacitors in series with the coil, the SS topology transmission model can achieve higher transmission efficiency and faster charging time. Furthermore, continuous wireless energy transfer between three sensing units is achieved through relay-based WPT, with a transmission efficiency of up to 80%. The tilt angle experiments indicate that the device can be applied to 3-D measurement of underground deformation, providing a basis for early warning of future landslide disasters.