指向式旋转导向钻井系统角位置测量方法

Angular position measurement method for directional rotary steerable drilling system

指向式旋转导向工具在国内的研究起步晚,许多技术环节还处于攻关阶段。该系统钻头轴(或偏心轴)与钻铤的相对角位置测量是工具在导向过程中保持工具面相对大地稳定的关键和前提,其精确度和实时性至关重要。在研究指向式旋转导向系统工具结构和工具面测量原理的基础上,对利用旋转变压器的2种角位置测量方法——反正切法和鉴相法进行适用性对比分析,对2种算法进行了仿真,并优选鉴相法开展实验室平台验证。仿真及实验结果证明,在电动机模拟井下转动并受干扰的情况下,鉴相法比反正切法处理后的信号具有更强的稳定性,能够较好地实时跟踪并高精度还原工具偏心轴相对于外部钻铤的转动角度,为钻头轴工具面角的测量、导向控制以及整个工具的研制提供了基础。

The study of directional rotary steerable drilling tool started relatively late in our country and many key parts are stillin research stage. The measurement of relative angular position of bit axis （eccentric shaft） and drill collar of the system is the key andprerequisite for drilling tool maintaining a relatively large stable tool face during steering, so its accuracy and instantaneity are verycritical. Based on the research on tool structure and tool face measurement principle of directional rotary steerable drilling system,contrastive analysis was conducted to the applicability of arctangent method and phase discrimination method, which are two kinds ofangular position measurement methods using resolver. Two corresponding algorithms are simulated and confirmatory tests are carriedout for phase discrimination method in lab. The simulation and test results prove that, in the case of simulated downhole motor rotationand interference, phase discrimination method has higher stability in signals treated by arctangent method, and can track in real-time andreduce in high precision the rotation angle of tool eccentric shaft relative to drill collar, providing basis for tool face angle measurement,steering control and development of the entire tool.