Well trajectory control technique by minimum curvature method

In order to further improve well trajectory calculation with minimum curvature method, a series of parametric equations are derived through mathematical analysis method in this article. These equations can directly calculate space coordinate, inclination angle, azimuth angle, instantaneous tool face angle, inclination angle varying rate, and azimuth angle varying rate of any well path point. The calculation of inclination angle and tool face angle is meticulously treated to overcome the defect of present equations. The influence of tool face angle on well trajectory variation is discussed, and the variation characteristics of inclination angle and azimuth angle in four typical conditions of preliminary tool face angle are analyzed. The calculation method presented can not only be used in the calculation of actual well trajectory, but also be used for well trajectory design, providing new ideas for optimizing plans. Besides, it can be used in well trajectory prediction and well trajectory control as well.