Presentation by Dr. Geoff Downton, Schlumberger - Control Systems ...

Supporting Slides for the
Call for Abstracts
Joint Society Invited Session on Drilling Systems
Automation and Control
2011 IEEE Multi-Conference on Systems and Control
September 28-30, Denver, Colorado
G C Downton
Schlumberger

Introduction
• Recently the drilling community supported by the
Society of Petroleum Engineers (SPE) has shown great
interest in the automation of the drilling process, for
reasons of efficiency, consistency of operation, safety,
and the ability to solve many problems beyond human
control.
• The relevance of Control Systems Engineering to these
new drilling challenges has never been stronger.
• This call for abstracts seeks work that combines Control
Systems Engineering with Borehole Drilling Systems.
• Topics of interest mentioned in the call follow.

System Overview

Managed Pressure Drilling (MPD) Control
Systems
• While drilling a borehole, a special drilling-fluid is
pumped into the borehole to flush the rock cuttings to
the surface.
• The distributed pressures and flow rates of this fluid
influence the ebb and flow of fluids into the rock.
• Too much pressure and the rock splits and fluid is lost,
too little and the well flows back to the surface.
• MPD significantly improves the situation by actively
managing the state of the drilling-fluid by automatically
adjusting valves and pumps at the surface or downhole.

Architectures
• Suitable control system architectures are
needed to support the evolution of reliable
and safe automated drilling systems to have
guaranteed performance and guaranteed
robustness in the face of changing
uncertainties and poor models.

Power Control Architectures

Communication Architectures

Control Architectures

Optimization and control of the speed
of drilling
• The challenge here is how best to control the
rotation and loads applied to a long slender beam
(drill string) in the absence of full knowledge
about how it is contacting the borehole while
passing through rock formations with uncertain
and rapidly changing properties?
• This subject has many aspects, including the
• This subject has many aspects, including the
control of vibrations in distributed media and the
efficiency of delivering drilling energy to the bit.

Complex Interface Interactions

Complex System Dynamics

Automating the steering and trajectory control
of a directionally controlled drilling system
• A particular problem is how to deal with the
effects of spatial and temporal delays created
by sensor placements and slow
communications systems.

Determining Position

Determining Future Direction

Action Space
• The drilling process is made up of many
discrete actions - what are the best tools and
techniques to capture the full variety of
behaviours.

Model Inversion and Wired Drill Pipe
• In order to optimize and control any process a
model is required. In drilling these models
concern systems that are spatially distributed, are
of uncertain form, and under go change as a
consequence of drilling.
• To day the measurement of state are slow,
delayed, and sparse but with the advent of wired
drill pipe communication speeds and distribution
of sensors improve massively.
• Given this recent advance what does the state of
the art in model inversions allow us to achieve?

High Bandwidth Bi Directional Communication between
surface and tools down hole

Supervisory control
• Considerations of how intelligent systems and
humans can work effectively together
• Potential topics may include reliability of man-
machine systems, the modelling of human
cognitive response, automatic fault detection,
system robustness to unforeseen failures, etc..

Drilling Systems Automation – highly distributed
sensing, control and communications systems

Education
• What training is needed to ensure control
systems engineers are equipped to research
and develop future solutions to the
automation of drilling ?

Questions