Optimizing algorithm for controlling drill string driver

Patent metadata

Field	Value
Publication number	US-11814942-B2
Application number	US-202017088735-A
Country	US
Kind code	B2
Filing date	Nov 4, 2020
Priority date	Nov 4, 2019
Publication date	Nov 14, 2023
Grant date	Nov 14, 2023

Abstract

Apparatus and methods for optimizing a stick-slip algorithm for controlling a driver of a drill string. A method may include commencing operation of a control system for controlling the driver. The control system may have a processor and a memory storing a computer program code, which may include the stick-slip algorithm. The operating control system may receive a plurality of different numerical parameters, and for each of the different numerical parameters, incorporate the numerical parameter into the stick-slip algorithm and execute the stick-slip algorithm to determine a control command that causes the driver to rotate the drill string to perform drilling operations while reducing amplitude of rotational waves travelling along the drill string.

First claim

What is claimed is:

1. An apparatus comprising:
a control system operable to control a driver for rotating a drill string, wherein the control system comprises one or more sensors operable to facilitate measurements indicative of one or more characteristics of one or more corresponding portions of the drill string, wherein the control system comprises a processor and a memory storing a computer program code, wherein the computer program code comprises a stick-slip algorithm, and wherein the control system is operable to:
execute the stick-slip algorithm to determine a control command that causes the driver to rotate the drill string to perform drilling operations while reducing rotational waves travelling along the drill string, wherein the stick-slip algorithm:
determines amplitude of the rotational waves travelling along the drill string based on the measurements for each of different numerical parameters; and
determines optimal ones of the different numerical parameters based on the determined amplitudes of the rotational waves, wherein the optimal ones of the different numerical parameters are associated with the lowest of the determined amplitudes of the rotational waves.

2. The apparatus of claim 1 wherein:
the one or more sensors comprise a torque sensor operable to facilitate torque measurements indicative of torque at a corresponding portion of the drill string; and
wherein the stick-slip algorithm determines amplitude of the rotational waves travelling along the drill string based on the torque measurements for each of the different numerical parameters.

3. The apparatus of claim 2 wherein the torque sensor is a surface torque sensor operable to facilitate torque measurements indicative of torque at an upper end of the drill string.

4. The apparatus of claim 1 wherein:
the one or more sensors comprise a rotational speed sensor operable to facilitate rotational speed measurements indicative of rotational speed of a corresponding portion of the drill string; and
wherein the stick-slip algorithm determines amplitude of the rotational waves travelling along the drill string based on the rotational speed measurements for each of the different numerical parameters.

5. The apparatus of claim 4 wherein the rotational speed sensor is a downhole rotational speed sensor operable to facilitate rotational speed measurements indicative of rotational speed at a lower end of the drill string.

6. The apparatus of claim 1 wherein the different numerical parameters comprise at least one of:
a speed integral constant;
a speed proportionality constant; and
a torque proportionality constant.

7. The apparatus of claim 1 wherein, before executing the stick-slip algorithm, the control system is further operable to:
receive an intended average rotational speed set-point of the drill string;
incorporate the intended average rotational speed set-point of the drill string into the stick-slip algorithm;
receive specifications of the drill string and/or the driver; and
incorporate the specifications of the drill string into the stick-slip algorithm.

8. The apparatus of claim 1 wherein, for each of the different numerical parameters, the control system is further operable to output a different torque command to the driver to thereby cause the driver to output a different amount of torque to rotate the drill string.

9. A method comprising:
commencing operation of a control system for controlling a driver of a drill string, wherein the control system receives measurements indicative of one or more characteristics of one or more corresponding portions of the drill string, wherein the control system comprises a processor and a memory storing a computer program code, wherein the computer program code comprises a stick-slip algorithm, and wherein the operating control system:
executes the stick-slip algorithm to determine a control command that causes the driver to rotate the drill string to perform drilling operations while reducing rotational waves travelling along the drill string, wherein the stick-slip algorithm:
determines amplitude of the rotational waves travelling along the drill string based on the measurements for each of different numerical parameters; and
determines optimal ones of the different numerical parameters based on the determined amplitudes of the rotational waves, wherein the optimal ones of the different numerical parameters are associated with the lowest of the determined amplitudes of the rotational waves.

10. The method of claim 9 wherein the operating control system:
receives torque measurements indicative of torque at a corresponding portion of the drill string; and
determines an amplitude of the rotational waves travelling along the drill string based on the torque measurements for each of the different numerical parameters.

11. The method of claim 9 wherein the operating control system:
receives rotational speed measurements indicative of rotational speed of a corresponding portion of the drill string; and
determines an amplitude of the rotational waves travelling along the drill string based on the rotational speed measurements for each of the different numerical parameters.

12. The method of claim 9 wherein the different numerical parameters comprise at least one of:
a speed integral constant;
a speed proportionality constant; and
a torque proportionality constant.

13. The method of claim 9 wherein, before executing the stick-slip algorithm, the operating control system also:
receives an intended average rotational speed set-point of the drill string;
incorporates the intended average rotational speed set-point of the drill string into the stick-slip algorithm;
receives specifications of the drill string and/or the driver; and
incorporates the specifications into the stick-slip algorithm.

14. The method of claim 9 wherein, for each of the different numerical parameters, the operating control system also outputs a different torque command to the driver thereby causing the driver to output a different amount of torque to rotate the drill string.

15. A method comprising:
commencing operation of a processing device to run a computer simulation of a drill string being rotated by a driver to drill a wellbore, wherein rotation of the driver is controlled by a stick-slip algorithm, and wherein the operating processing device:
executes the stick-slip algorithm to determine a control command that causes the driver to rotate the drill string to perform drilling operations while reducing amplitude of rotational waves travelling along the drill string, wherein the stick-slip algorithm:
determines the amplitude of the rotational waves travelling along the drill string for each of the different numerical parameters; and
determines optimal ones of the different numerical parameters based on the determined amplitudes of the rotational waves, wherein the optimal ones of the different numerical parameters are associated with the lowest of the determined amplitudes of the rotational waves.

16. The method of claim 15 wherein the different numerical parameters comprise at least one of:
a speed integral constant;
a speed proportionality constant; and
a torque proportionality constant.

17. The method of claim 15 wherein, before executing the stick-slip algorithm, the operating processing device also:
receives an intended average rotational speed set-point of the drill string;
incorporates the intended average rotational speed set-point of the drill string into the stick-slip algorithm;
receives specifications of the d

Assignees

• Schlumberger Technology Corp

Inventors

• Jeffryes Benjamin Peter
• Wicks Nathaniel
• Wu Jian

Classifications

• E21B44/04 Primary

  in response to the torque of the drive {; Measuring drilling torque (E21B44/06 takes precedence; measuring stresses in a well bore pipe E21B47/007)} · CPC title

• E21B44/08

  in response to the amplitude of the movement of the percussion tool, e.g. jump or recoil · CPC title