A fuzzy PID method for suppressing drilling stick-slip vibration by introducing a Smith predictor

During the drilling process of an oil rig, the torsional stiffness decrease as the drilling depth increase and it leads to a stick-slip vibration of the drill string system. The dynamic process of torsional stiffness and moment of inertia is complex while it is hard to control the influence of model parameters. In this paper, the mechanism of vibration that meets the actual situation is analyzed, and a new method that uses fuzzy PID control with the Smith predictor is proposed. The simulation and results show that the proposed method can suppress the hysteresis effect and has a certain inhibitory effect on the occurrence of stick-slip vibration.