Bucking to improve permanent reservoir monitoring sensitivity

Patent metadata

Field	Value
Publication number	US-10948622-B2
Application number	US-201515759806-A
Country	US
Kind code	B2
Filing date	Dec 17, 2015
Priority date	Dec 17, 2015
Publication date	Mar 16, 2021
Grant date	Mar 16, 2021

Abstract

A well monitoring system includes a plurality of transmitter coils coupled to an exterior of a casing positioned within a wellbore, wherein one or more first transmitter coils are positioned at a first location and one or more second transmitter coils are positioned at a second location axially offset from the first location. At least one receiver coil is coupled to the exterior of the casing and positioned at the second location. A power source is communicably coupled to the one or more first and second transmitter coils. The one or more first transmitter coils generates a magnetic field detectable by the at least one receiver coil, and the one or more second transmitter coils generates a bucking signal that minimizes a direct coupling between the one or more first transmitter coils and the at least one receiver coil.

First claim

What is claimed is:

1. A well monitoring system, comprising:
a plurality of transmitter coils coupled to an exterior of a casing positioned within a wellbore, wherein one or more first transmitter coils are positioned at a first location and one or more second transmitter coils are positioned at a second location axially offset from the first location;
at least one receiver coil coupled to the exterior of the casing and positioned at the second location, wherein the at least one receiver coil and the one or more second transmitter coils are axially spaced from each other at the second location; and
a power source that generates a first cycle and a second cycle, the power source communicably coupled to the one or more first and second transmitter coils, wherein the one or more first transmitter coils generates a magnetic field detectable by the at least one receiver coil in response to the first cycle, and the one or more second transmitter coils generates a bucking signal that minimizes a direct coupling between the one or more first transmitter coils and the at least one receiver coil in response to the first cycle, wherein the one or more second transmitter coils generates a magnetic field detectable by the at least one other receiver coil in response to the second cycle, and the one or more first transmitter coils generates a bucking signal that minimizes a direct coupling between the one or more second transmitter coils and the at least one other receiver coil;
wherein casing is wellbore lining that includes lengths of pipe coupled end to end using at least one casing collar.

2. The well monitoring system of claim 1 , wherein the first and second locations correspond to casing collars coupled to the casing.

3. The well monitoring system of claim 1 , wherein the at least one receiver coil is a first receiver coil, the well monitoring system further comprising:
one or more third transmitter coils positioned at a third location axially offset from the second location such that the second location axially interposes the first and third locations;
a second receiver coil coupled to the exterior of the casing and positioned at the third location and axially offset from the one or more third transmitter coils;
a first power line extending from the power source and being communicably coupled to the one or more first and third transmitter coils; and
a second power line extending from the power source and being communicably coupled to the one or more second transmitter coils, wherein, in a first cycle, the first power line provides a main current to the one or more first and third transmitter coils to generate the magnetic field and the second power line provides a bucking current to the one or more second transmitter coils to generate the bucking signal, and
wherein, in a second cycle, the second power line provides the main current to the one or more second transmitter coils to generate the magnetic field and the first power line provides the bucking current to the one or more first and third transmitter coils to generate the bucking signal that minimizes a direct coupling between the one or more second transmitter coils and the second receiver coil.

4. The well monitoring system of claim 1 , wherein the at least one receiver coil is communicably coupled to a surface interface via a communication cable extended into the wellbore.

5. The well monitoring system of claim 4 , wherein the communication cable includes one or more optical waveguides and the surface interface comprises:
a light source that launches light into the one or more optical waveguides;
an optical detector that receives reflected light from the at least one receiver coil; and
a computer that processes measurement data from the optical detector.

6. The well monitoring system of claim 1 , wherein the at least one receiver coil is a first receiver coil, the well monitoring system further comprising:
one or more third transmitter coils positioned at a third location axially offset from the second location such that the second location axially interposes the first and third locations;
a second receiver coil coupled to the exterior of the casing and positioned at the third location and axially offset from the one or more third transmitter coils;
a third receiver coil coupled to the exterior of the casing and positioned at the first location and axially offset from the one or more first transmitter coils;
a first power line extending from the power source and being communicably coupled to the one or more first transmitter coils;
a second power line extending from the power source and being communicably coupled to the one or more second transmitter coils; and
a third power line extending from the power source and being communicably coupled to the one or more third transmitter coils,
wherein, in a first cycle, the first power line provides a main current to the one or more first transmitter coils to generate the magnetic field, the second power line provides a bucking current to the one or more second transmitter coils to generate the bucking signal, and the third power line is inactive,
wherein, in a second cycle, the second power line provides the main current to the one or more second transmitter coils to generate the magnetic field, the third power line provides the bucking current to the one or more third transmitter coils to generate the bucking signal that minimizes a direct coupling between the one or more second transmitter coils and the second receiver coil, and the first power line is inactive, and
wherein, in a third cycle, the third power line provides the main current to the one or more third transmitter coils to generate the magnetic field, the first power line provides the bucking current to the one or more first transmitter coils to generate the bucking signal that minimizes a direct coupling between the one or more first transmitter coils and the third receiver coil, and the second power line is inactive.

7. The well monitoring system of claim 1 , further comprising:
a power line that provides a signal to the one or more first and second transmitter coils,
wherein the one or more first transmitter coils are wound in a first direction over a first number of turns and the one or more second transmitter coils are wound in a second direction over a second number of turns, where the first direction is opposite the second direction, and the first number of turns is greater than the second number of turns.

8. The well monitoring system of claim 1 , further comprising:
a power line that provides a signal to the one or more first and second transmitter coils,
wherein at least one of the one or more second transmitter coils is wound in a first direction over a first number of turns and at least another one of the one or more second transmitter coils is wound in a second direction over a second number of turns, where the first direction is opposite the second direction, and the first number of turns is greater than the second number of turns.

9. A method, comprising:
generating, in a first cycle, a magnetic field and, in a second cycle, a bucking signal with at least one transmitting coil coupled to an exterior of a casing positioned within a wellbore, wherein the at least one transmitting coil is positioned at a first location along the casing;
detecting, in response to the first cycle, the magnetic field with at least one receiver coil coupled to the exterior of the casing and positioned at a second location axially offset from the first location;
generating, in the first cycle, i another bucking signal and, in the second cycle, another magnetic field with at least one bucking other transmitting coil coupled to the exterior of the casing at the seco

Assignees

• Halliburton Energy Services Inc

Inventors

• Samson Etienne
• Fouda Ahmed E
• Donderici Burkay
• Wilson Glenn Andrew

Classifications

• E21B47/113

  using electrical indications; using light radiations · CPC title

• G01V3/28 Primary

  using induction coils · CPC title

• E21B43/20

  Displacing by water · CPC title

• G01V3/34

  Transmitting data to recording or processing apparatus; Recording data · CPC title

• E21B47/10

  Locating fluid leaks, intrusions or movements · CPC title