OPTIMAL TRAJECTORY CONTROL FOR DIRECTIONAL DRILLING

摘要

A feedback control system for steering a tool along a well-plan. Optimum steering instructions may be generated by a recursive optimization of multiple objectives. These objectives can include accuracy and quality. The quality objective can include the objective of drilling a smooth borehole by minimizing strain energy and torsion. The accuracy objective can include the objective of minimizing the deviation of the borehole trajectory during the real-time drilling process from a predefined well-plan. The trajectory control problem, therefore, can be a multi-objective problem where, in some embodiments, the weightings of the individual objectives can be adjusted along the process.

主权项

1. A method for determining an optimal borehole trajectory in real-time for drilling a borehole in a drilling procedure using a drilling system through an earth formation, comprising:
receiving a well-plan, wherein the well-plan is designed to describe a goal borehole extending from a surface location to a goal in the earth formation, wherein the goal is a volume of hydrocarbons in the earth formation; receiving real-time drill bit and/or borehole data during the drilling procedure; and determining a borehole trajectory based on the well plan, the drill bit and/or borehole data, wherein the borehole trajectory is determined using a plurality of objectives comprising at least a first objective of minimizing at least one of strain energy and torsion and a second objective of minimizing deviation of the borehole trajectory from the well-plan.