面向油气钻井振动测量的空间三轴加速度传感器阵列研究

Method of drilling vibration measurement based on spatial array of accelerometers

在油气钻井领域中,由于钻杆柱长细比极大、地层非均质、作业参数不稳定等因素影响,钻头在井下存在多主频、多维度、多振幅复合的六自由度复杂振动,严重制约了油气钻井的安全高效进行。基于刚体运动理论,常规平面阵列方案存在方程欠定问题,难以进行角速度推算;常规空间阵列方案则需要在Z轴安装阵列传感器,无法满足钻井领域钻具内部中空预留流体通道的要求。文章设计了一种六棱柱框架的空间加速度传感器阵列,以同心圆形式预留中央流体通道,基于无约束最小二乘与神经网络推算,通过冗余配置实现了钻具三轴振动(加速度)与扭转(角速度、角加速度)的求解,载体等效坐标系振动参数推算误差小于5×10^(-3),符合油气钻井领域应用标准,为油气钻井领域振动调制创造了数据基础,并对常规领域传感器振动测试技术的工程实现具有一定的借鉴意义。

Affected by slenderness ratio of drilling string,anisotropism of formation,unstable parameter of operation,drilling bit suffers a complex vibration of six degrees of freedom with multiple dominant frequency,dimension and amplitude.It seriously restricts the safety and efficiency of drilling operation.According to the theory of rigid motion,the angular velocity reckoning is difficult by the current planar array scheme,and central fluid channel cannot be reserved by the conventional space array.In this paper,a spatial array with a central fluid channel was proposed.Least squares and neural network was also established to reckoned the vibration parameters.The average error of reckoned vibration parameters is less than 5×10^(-3),which meet the application requirements of drilling operation.The proposed method and array scheme provide the data base to the vibration conditioning of drilling string,and contribute to the research of sensor vibration test.