邻井距离随钻电磁探测系统的设计与实现

虚拟二维激光雷达是激光雷达扩展应用的组成部分，可以结合3D场景点云特征进行二维激光雷达扫描障碍物模拟。提出根据光线传导特征建立积分方程得到了在多障碍物场景下的激光雷达图生成的解析解，利用AutoCAD与Visual C#联合编程的方法进行了虚拟激光雷达的实现。最后，实验结果与真实二维激光雷达比对，虚拟激光雷达能从3D场景中准确提取物体的位置和距离信息。

Design and Implementation of Electromagnetic Detection System for Distance of Adjacent Wells

Adjacent wells distance measurement while drilling is one of the key technologies to fine-grained control of complex structures wellbore trajectory. Based on the principle of rotating magnet ranging, an electromagnetic adjacent well detection system while drilling is developed. A magnetic short section is designed and installed behind the drill bit to generate the alternating magnetic field, a tri-axial magnetic field sensor is located in the adjacent well as a signal receiver, and a low-noise, narrow pass band, high-precision data acquisition circuit is developed to detect the weak low-frequency magnetic field signal. A filtering method based on the modified DFT peak spectrum value is proposed to track the alternating magnetic frequency accuratly and extract the magnetic amplitude precisely. The Manchester code communication is used to transmit the downhole data to the surface instrument. The surface instrument calculates the distance and orientation between adjacent wells and guides drilling operations. The outdoor and field tests showed that the maximum measurement distance range of the developed system is up to 50 meters, which can meet the actual demand of drilling engineering.