Analysis and Control of Stick-Slip Oscillations in Drilling Systems
2016 (English)In: IEEE Transactions on Control Systems Technology, ISSN 1063-6536, E-ISSN 1558-0865, Vol. 24, no 5, 1582-1593 p.Article in journal (Refereed) Published
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.
Place, publisher, year, edition, pages
IEEE , 2016. Vol. 24, no 5, 1582-1593 p.
Control of drilling systems, delay-differential equations (DDEs), linearization of DDEs, stick-slip oscillations, time scale analysis and averaging
IdentifiersURN: urn:nbn:se:kth:diva-192716DOI: 10.1109/TCST.2015.2502898ISI: 000381506100005ScopusID: 2-s2.0-84949947222OAI: oai:DiVA.org:kth-192716DiVA: diva2:974256
QC 201609262016-09-262016-09-202016-09-26Bibliographically approved