Analysis and control of stick-slip oscillations in drilling systemsBesselink, B., Vromen, T., Kremers, N. & van de Wouw, N., Sep-2016, In : IEEE Transactions on Control Systems Technology. 24, 5, p. 1582-1593 12 p.
Research output: Contribution to journal › Article › Academic › peer-review
This paper proposes feedback control strategies for the mitigation of torsional stick-slip oscillations in drilling systems using drag bits. Herein, we employ a model for the coupled axial–torsional drill-string dynamics in combination with a rate-independent bit-rock interaction law including both cutting and frictional effects. Using a singular perturbation and averaging approach, we show that the dynamics of this model generate an apparent velocity-weakening effect in the torque-on-bit, explaining the onset of torsional stick-slip vibrations. Based on this dynamic analysis, the (decoupled) torsional dynamics can be described by a delay-differential equation with a state-dependent delay. Using this model, we propose both state- and output-feedback control strategies for the mitigation of torsional stick-slip oscillations, where the latter strategy uses surface measurements only. The effectiveness of the proposed approaches is shown in a simulation study.
|Number of pages||12|
|Journal||IEEE Transactions on Control Systems Technology|
|Publication status||Published - Sep-2016|
- Analytical models, Delays, Drag, Mathematical model, Oscillators, Torque, Vibrations, Control of drilling systems, delay-differential equations (DDEs), linearization of DDEs, stick-slip oscillations, time scale analysis and averaging, SELF-EXCITED VIBRATIONS, OIL-WELL DRILLSTRINGS, DRAG BITS, COUPLED VIBRATIONS, MODEL, STABILITY, DELAY