Toroidal choke inductor for wireless communication and control

• US 7,055,592 B2
• Filed: 10/20/2003
• Issued: 06/06/2006
• Est. Priority Date: 01/24/2000
• Status: Expired due to Fees

• Current Assignee: Shell Oil Company (Shell Plc)
• Original Assignee: Shell Oil Company (Shell Plc)
• Inventors: Savage, William Mountjoy, Bass, Ronald Marshall, Burnett, Robert Rex, Vinegar, Harold J., Carl, Frederick Gordon Jr.
• Primary Examiner(s): Bagnell, David
• Assistant Examiner(s): Stephenson, Daniel P
• Application Number:
  US10/689,470
• Publication Number:
  US 20040079524A1
• Time in Patent Office: 960 Days
• Field of Search: 166/65.1, 166/66.5, 174/71.C, 174/74.A, 174/105.R, 3408543-8546, 340/854.8, 324/355, 324/368, 324/373, 324/371, 324/363
• US Class Current: 166/66.5
• CPC Class Codes: E21B 17/003 with electrically conducting or insulating means E21B17/028 and E21B17/023 take precedence
• CPC Class Codes: E21B 17/0283 characterised by the coupling being contactless, e.g. inductive
• CPC Class Codes: E21B 17/0285 characterised by electrically insulating elements
• CPC Class Codes: E21B 2200/22 Fuzzy logic, artificial intelligence, neural networks or the like
• CPC Class Codes: E21B 33/1294 characterised by a valve, e.g. a by-pass valve
• CPC Class Codes: E21B 34/066 electrically actuated
• CPC Class Codes: E21B 34/08 responsive to flow or pressure of the fluid obtained E21B34/10 takes precedence
• CPC Class Codes: E21B 34/16 Control means therefor being outside the borehole control systems for submerged well heads E21B33/0355
• CPC Class Codes: E21B 37/06 using chemical means for preventing or limiting , e.g. eliminating, the deposition of paraffins or like substances
• CPC Class Codes: E21B 41/0085 Adaptations of electric power generating means for use in boreholes
• CPC Class Codes: E21B 41/02 in situ inhibition of corrosion in boreholes or wells
• CPC Class Codes: E21B 43/12 Methods or apparatus for controlling the flow of the obtained fluid to or in wells E21B43/25 takes precedence; valve arrangements E21B34/00
• CPC Class Codes: E21B 43/1235 characterised by electromagnetic actuation
• CPC Class Codes: E21B 43/14 Obtaining from a multiple-zone well
• CPC Class Codes: E21B 43/16 Enhanced recovery methods for obtaining hydrocarbons
• CPC Class Codes: E21B 47/06 Measuring temperature or pressure
• CPC Class Codes: E21B 47/103 using thermal measurements
• CPC Class Codes: E21B 47/107 using acoustic means
• CPC Class Codes: E21B 47/11 using tracers; using radioactivity
• CPC Class Codes: E21B 47/12 Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling
• CPC Class Codes: E21B 47/13 : by electromagnetic energy, e.g. radio frequency
• CPC Class Codes: H04B 13/02 : Transmission systems in which the medium consists of the earth or a large mass of water thereon, e.g. earth telegraphy

Abstract

An induction choke in a petroleum well where a voltage potential is developed across the choke to power and communicate with devices and sensors in the well. Preferably, the induction choke is a ferromagnetic material and acts as an impedance to a time-varying current, e.g. AC. The petroleum well includes a cased wellbore having a tubing string positioned within and longitudinally extending within the casing. A controllable gas lift valve, sensor, or other device is coupled to the tubing. The valve sensor, or other device is powered and controlled from the surface. Communication signals and power are sent from the surface using the tubing, casing, or liner as the conductor with a casing or earth ground. For example, AC current is directed down a casing or tubing or a lateral where the current encounters a choke. The voltage potential developed across the choke is used to power electronic devices and sensors near the choke. Such induction chokes may be used in many other applications having an elongated conductor such as a pipe, where it is desirable to power or communicate with a valve, sensor, or other device without providing a dedicated power or communications cable.

Claims

1. A passive impedance device for creating a voltage differential when time variant current is applied to a tubular connected to a top and bottom connection to the passive impedance device, the passive impedance device comprising:

a tubular having a threaded connection at a first end of the tubular and a threaded connection at a second end of the tubular;

a plurality of subsections surrounding the tubular, each subsection comprising a plurality of layers of a ferromagnetic alloy, each layer separated by an electrically insulating material;

a non-electrically conductive insulator between each of the subsections; and

a protective covering over the plurality of subsections.

2. The passive impedance device of claim 1 wherein the protective covering is a shrink-wrapped polymer tube.

3. The passive impedance device of claim 1 wherein the protective covering is a shrink-wrapped polymer sheet.

4. The passive impedance device of claim 1 wherein the ferromagnetic alloy comprises about 86% nickel and about 14% iron.

5. The passive impedance device of claim 1 wherein the ferromagnetic alloy has a magnetic permeability of about 50,000.

6. The passive impedance device of claim 1 wherein the non-electrically conductive insulator between each of the subsections is a polymeric washer.

7. The passive impedance device of claim 6 wherein the polymeric washer is a polytetrafluoroethylene washer.

8. The passive impedance device of claim 1 wherein the subsections each comprise about 60 layers of the ferromagnetic alloy.

9. The passive impedance device of claim 1 wherein each of the layers of ferromagnetic alloy is about 0.014 inches in thickness.

10. The passive impedance device of claim 1 further comprising an electrical conductor passing from a connection to first end of the tubular extending outside of the subsections to a terminal near the second end of the tubular.

11. The passive impedance device of claim 10 further comprising an electrically operated device driven by voltage differences between the terminal and an electrical connection at the second end of the tubular.