井下能量收集与自供电转速测量传感技术研究

Research on downhole energy collection and self-powered speed measurement sensing technology

摘要:

小直径高造斜钻探中井下钻具的转速是反映工况的关键参数，目前转速测量的方案需要配套独立的传感单元与外部供电系统，不仅大幅增加了井下系统的复杂度，还容易受到井下极端环境的干扰，导致可靠性难以保障。摩擦纳米发电机（Triboelectric Nanogenerator, TENG）技术可以将环境中的机械能转化为电能，具有能量收集与自供电传感的双重属性，为破解井下供电与状态监测的双重难题提供了全新的技术路径。本研究设计了一套基于TENG的井下能量收集与自供电转速测量一体化传感器，并完成了传感器样机的加工装配，搭建了模拟井下工况的实验测试平台。结果表明：所设计的传感器工作转速范围在100-500 r/min之间，主能量收集区开路电压稳定在1.2 kV左右，300 rpm常规工况下峰值输出功率达4.273 mW，可实现4.7-220 μF储能电容的有效充电，具备较好的旋转机械能收集能力。

Abstract:

The rotational speed of the downhole drilling tool is a key parameter to reflect the working conditions. At present, the scheme of rotational speed measurement needs to be equipped with independent sensing unit and external power supply system, which not only greatly increases the complexity of the downhole system, but also is vulnerable to the interference of the underground extreme environment, which makes the reliability difficult to guarantee. Triboelectric nanogenerator ( TENG ) technology can convert mechanical energy in the environment into electrical energy, and has the dual attributes of energy collection and self-powered sensing, which provides a new technical path for solving the dual problems of downhole power supply and condition monitoring. In this study, a set of integrated device for downhole energy collection and self-powered speed measurement based on TENG was designed, and the processing and assembly of the device prototype was completed, and an experimental test platform for simulating downhole working conditions was built. The results show that the working speed range of the designed device is between 100-500 r/min, the open circuit voltage of the main energy collection area is stable at about 1.2 kV, and the peak output power is 4.273 mW at 300 rpm under conventional conditions. The device can realize the effective charging of 4.7-220 μF energy storage capacitor and has good rotating mechanical energy collection ability.