METHOD TO OPTIMIZE DRILLING EFFICIENCY WHILE REDUCING STICK SLIP

摘要

Reducing or eliminating stick-slip and vibrations downhole may include controlling top drive torque in order to adjust drill bit angular speed in a manner that prevents, eliminates, or reduces stick-slip and vibration. Control methods and systems may include solving one or more optimization problems including an objective function. The objective function may be subject to conditions including a physical model of the drilling system. The objective function may be minimized without reference to a model, but instead by reference to estimated stick-slip frequency based upon a drill bit angular speed profile. In addition, actual downhole measurements for use in control methods and systems, such as drill bit angular speed, may be estimated using an observer.