Drilling Systems Modeling & Automation, Part 5: Supervisory Logic Design

Drilling systems of today are designed around the human operator; the human verifies that equipment is reacting per applied set-points and interprets sensor readouts to decide proper actions. For future drilling control systems, it is likely that the greatest drilling cost savings will come from applications that not only use control to automate the drilling machines and equipment, but also to automate decisions in the supervisory control of these machines and equipment. The equipment controls are preprogrammed to act repeatedly based on defined inputs and known states, such as the auto driller.

In this video, we design an auto driller that senses the mass & current position of the top drive and automatically adjusts the motor speed setpoint. This is done by implementing the look-up table as a supervisory controller using state-based logic. We show how the supervisory control algorithm steps through the drawworks operating states such as raising and lowering the drillstring and stopping. This is implemented in Stateflow.

Stateflow enables you to design and develop supervisory control by building state charts. You can visualize system behavior using state diagram animations to highlight active states and transitions in your charts. Stateflow also allows you to graphically describe how MATLAB® algorithms and Simulink® models react to input signals, and time-based conditions.

Additional Resources:

- MATLAB for the Oil and Gas Industry: https://bit.ly/2FZqYXh - Simulator codes on File Exchange: https://bit.ly/31uCQZO - Simulator codes on GitHub: https://github.com/jonlesage/Drawwork...