Design and analysis of robust controllers for directional drilling tools

摘要

Directional drilling is a very important tool for the development of oil and gas deposits.Attitude control which enables directional drilling for the efficient placement of the directional drilling tools in petroleum producing zones is reviewed along with the variousengineering requirements or constraints. This thesis explores a multivariable attitude governing plant model as formulated in Panchal et al. (2010) which is used for developingrobust control techniques. An inherent input and measurement delay which accounts forthe plant's dead-time is included in the design of the controllers. A Smith Predictor controller is developed for reducing the effect of this dead-time. The developed controllersare compared for performance and robustness using structured singular value analysis andalso for their performance indicated by the transient response of the closed loop models. Results for the transient non-linear simulation of the proposed controllers are alsopresented. The results obtained indicate that the objectives are satisfactorily achieved.