Self-Powered Downhole Drilling Tools Vibration Sensor Based on Triboelectric Nanogenerator

The vibration state of the drilling tool is particularly important for its working condition monitoring. Here, a self-powered downhole drilling tools vibration sensor (hereafter referred to as V-TENG) based on triboelectric nanogenerator (TENG) is proposed. The V-TENG, which is designed as the single electrode and independent layer TENG, can synchronously realize the measurement of drilling tools vibration frequency and amplitude. Test results show that the frequency measuring range is 0 to 13 Hz, with an error of no more than 5%, and the amplitude measuring range is 0 to 130 mm, with a resolution of 10 mm and a maximum deviation of 5 mm. In addition, the possibility of the sensor converting vibration energy into electrical energy and providing power for other measuring instruments was explored, the test results show that the maximum power of the frequency measuring module is $88.92\times 10$ ⁻⁸ W with $10^{8} {\boldsymbol \Omega } $ resistance in series, while the amplitude measurement is $28.62\times 10$ ⁻⁹ W with $10^{9} {\boldsymbol \Omega }$ resistance in series. Compared with traditional downhole vibration sensors, the V-TENG can synchronously measure the drill string vibration frequency and amplitude in a self-powered model, which is more suitable for downhole conditions.