Active sensor for torque measurement in a viscometer

Patent metadata

Field	Value
Publication number	US-11428615-B2
Application number	US-201716489104-A
Country	US
Kind code	B2
Filing date	Mar 31, 2017
Priority date	Mar 31, 2017
Publication date	Aug 30, 2022
Grant date	Aug 30, 2022

Abstract

Viscosity assemblies may be used to determine the viscosity of a sample fluid at a surface location under one or more downhole conditions prior to pumping or flowing of the sample fluid downhole. A viscosity assembly may include a bob assembly disposed in a container that includes a bob disposed about a magnet rotor that rotates when a shear force is applied by the flow of the sample fluid in the container. A stator coil may receive a control signal that induces a force or a voltage that causes the magnet rotor to rotate the bob by a predetermined distance to position the bob from the rotated position back to the initial position.

First claim

What is claimed is:

1. A viscosity measurement system, comprising:
a shaft;
a bob assembly disposed about the shaft, wherein the bob assembly comprises a bob, wherein the shaft is disposed through the bob, and wherein the bob is coupled to an outside of the shaft;
a container disposed about the bob assembly;
a magnet rotor coupled to the bob for rotating the bob due to a force, wherein the shaft is disposed through the magnet rotor, wherein the magnet rotor is coupled to the outside of the shaft;
a stator coil comprising a first winding and a second winding for inducing the force on the magnet rotor to cause the magnet rotor to rotate the bob, wherein the first winding and the second winding are disposed opposite each other;
a positional sensor disposed about the shaft to detect rotational position information associated with the bob; and
a processor device configured to:
cause a fluid within the container to impart a shear force on the bob that creates a torque on the bob to rotate the bob disposed within the container from an initial position;
determine a rotated distance of the bob from the initial position;
determine a counter torque required to rotate the bob by the rotated distance to position the bob back at the initial position;
transmit a control signal to the stator coil to include a counter torque force on the magnet rotor to rotate the bob back to the initial position; and
determine a viscosity of the fluid based, at least in part, on the counter torque.

2. The viscosity measurement system of claim 1 , further comprising an amplifier system to generate a control signal.

3. The viscosity measurement system of claim 2 , wherein the amplifier system comprises a summing amplifier and a bidirectional linear amplifier.

4. The viscosity measurement system of claim 2 , further comprising a proportional integral derivative (PID) controller.

5. The viscosity measurement system of claim 1 , wherein the magnet rotor is disposed within the bob assembly.

6. The viscosity measurement system of claim 1 , wherein the stator coil comprises at least two sensor windings.

7. The viscosity measurement system of claim 1 , wherein the stator coil is disposed about the magnet rotor.

8. A method for determining a viscosity of a fluid, comprising:
placing the fluid within a container;
placing a bob within the container at an initial position, wherein the fluid flows about the bob;
imparting a shear force by the fluid on the bob disposed within the container that creates a torque on the bob;
determining a rotated distance of the bob from the initial position;
determining a counter torque required to rotate the bob by the rotated distance to position the bob back at the initial position;
inducing the counter torque by a stator coil on a magnet rotor coupled to the bob to rotate the bob back to the initial position; and
determining the viscosity of the fluid based, at least in part, on the counter torque.

9. The method for determining the viscosity of the fluid of claim 8 , further comprising:
communicating positional information associated with the bob to a controller; and
determining a positional error value based, at least in part, on the positional information.

10. The method for determining the viscosity of the fluid of claim 8 , further comprising:
determining a friction compensation for the bob;
determining an inertial compensation for the bob;
determining a compensation voltage based on the friction compensation and the inertial compensation; and
wherein the counter torque is based, at least in part, on the compensation voltage.

11. The method for determining the viscosity of the fluid of claim 10 , further comprising:
determining a positional error based on the rotated distance and the initial position;
generating a positional rotation signal based on the compensation voltage; and
wherein the counter torque is based, at least in part, on the positional rotation signal.

12. The method for determining the viscosity of the fluid of claim 8 , wherein inducing the counter torque by the stator coil comprises energizing a plurality of windings to induce a magnetic field.

13. The method for determining the viscosity of the fluid of claim 8 , wherein inducing the counter torque by the stator coil comprises receiving a counter torque control signal, wherein the counter torque is based on the counter torque control signal.

14. The method of claim 8 , further comprising altering at least one of a temperature or a pressure of the fluid.

15. A non-transitory computer readable medium storing one or more instructions that, when executed, causes a processor to:
rotate a bob disposed within a container from an initial position by causing a fluid within the container to impart a shear force on the bob that creates a torque on the bob;
determine a rotated distance of the bob from the initial position;
determine a counter torque required to rotate the bob in a counter torque direction by the rotated distance to position the bob back at the initial position;
transmit a control signal to a stator coil to induce a counter torque on a magnet rotor coupled to the bob to rotate the bob back to the initial position; and
determine a viscosity of the fluid based, at least in part, on the counter torque.

16. The non-transitory computer readable medium of claim 15 , wherein the one or more instructions that, when executed, further cause the processor to determine a positional error value based, at least in part, on positional information associated with the bob received from the stator coil.

17. The non-transitory computer readable medium of claim 15 , wherein the one or more instructions that, when executed, further cause the processor to:
determine a friction compensation for the bob;
determine an inertial compensation for the bob;
determine a compensation voltage based on the friction compensation and the inertial compensation; and
wherein the counter torque is based, at least in part, on the compensation voltage.

18. The non-transitory computer readable medium of claim 15 , wherein the one or more instructions that, when executed, further cause the processor to:
determine a positional error based on the rotated distance and the initial position;
generate a positional rotation signal based on a compensation voltage; and
wherein the counter torque is based, at least in part, on the positional rotation signal.

19. The non-transitory computer readable medium of claim 15 , wherein the control signal comprises a predetermined voltage.

20. The non-transitory computer readable medium of claim 15 , wherein the one or more instructions that, when executed, further cause the processor to alter at least one of a temperature or a pressure of the fluid.

Assignees

• Halliburton Energy Services Inc

Inventors

• Gajji Bhargav
• Bhaidasna Ketan Chimanlal
• Morgan Richard Gary
• Sista Subrahmanyam Surya Venkata
• Mamilla Abhhilash
• Veedu Sandeep Mavinkal Kizhakke
• Vos Andrew David

Classifications

• G01N2011/147

  Magnetic coupling · CPC title

• G01N11/14 Primary

  by using rotary bodies, e.g. vane (G01N11/16 takes precedence) · CPC title

• G01N2203/0094

  Visco-elasticity · CPC title