基于加速度计和磁强计的定向钻进姿态测量及方位校正

描述了用三轴加速度计与三轴磁强计测量地下钻头倾斜角、工具面向角和方位角的方法,给出了具体的系统结构和详细的姿态解算。针对由于钻具铁磁性材料引入干扰磁场对方位测量的误差,提出了利用当地地磁场进行方位角校正的方法,并给出仿真结果。结果表明,这种校正方法能够在不更换钻具即测量装置仍放在一段无磁钻铤内部的情况下,获得准确的方位角,因此可以大大减少无磁钻铤的长度,节省钻进成本。

Directional Drilling Attitude Measurement and Azimuth Correction with Accelerometers and Magnetometers

This paper proposes an approach of determining the pitch,the roll and the azimuth with three mutually orthogonal accelerometers and magnetometers.The configuration of the system and the calculation of the attitude were firstly described.In order to compensate for the effects of perturbing magnetic fields associated with magnetized sections of the drill collar,a correction method of determining the azimuth which relies on the knowledge of local geomagnetic field was described in great detail.Furthermore,the correction process and simulation were presented.Results from simulation show that the correction method can determine an absolute azimuth by means of using a measuring instrument disposed in a relatively short non-magnetic drill collar,so it minimizes the length of non-magnetic drill collar and saves drilling costs greatly.