Electromagnetic harvesting of fluid oscillations for downhole power sources

• US 8,916,983 B2
• Filed: 09/10/2009
• Issued: 12/23/2014
• Est. Priority Date: 09/10/2009
• Status: Active Grant

• Current Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Original Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Inventors: Marya, Manuel P., Rytlewski, Gary L.
• Primary Examiner(s): GONZALEZ, JULIO CESAR
• Application Number:
  US12/556,655
• Publication Number:
  US 20110057449A1
• Time in Patent Office: 1,930 Days
• Field of Search: 290/54, 290/43, 166/66.5, 166/65.1
• US Class Current: 290/43
• CPC Class Codes: E21B 41/0085 Adaptations of electric power generating means for use in boreholes
• CPC Class Codes: F03B 13/02 Adaptations for drilling wells

Abstract

A downhole tool for generating power is provided that includes a conductive fluid disposed downhole within a tubular member, an energy harvesting apparatus, and a pressure changing apparatus. The energy harvesting apparatus includes a magnet configured to generate a magnetic field and an electrical conductor configured to move with respect to the magnet. The pressure changing apparatus is configured to supply a differential pressure across the energy harvesting apparatus, such that the electrical conductor moves with respect to the magnet.

Claims

1. An apparatus to generate power downhole, comprising:

a tubular member configured to have a fluid flow therein; and

an energy harvesting apparatus, comprising;

two or more permanent magnets connected together by a spring and configured to generate a magnetic field;

a liquid metal disposed around the two or more permanent magnets;

an inductance coil configured to move with respect to the two or more permanent magnets, wherein the inductance coil comprises at least one of a flexible diaphragm, a blade, or a flexible membrane;

a conductive fluid; and

a pressure changing apparatus having a fluid intake and a fluid outtake, the pressure changing apparatus configured to supply a differential pressure across the energy harvesting apparatus such that the inductance coil moves with respect to the two or more permanent magnets;

wherein the energy harvesting apparatus is disposed adjacent to the tubular member and is configured to receive a pressure change inflow from the tubular member via the fluid intake on a first side thereof and is configured to receive a pressure change outflow from the tubular member via the fluid outtake on a second side thereof to induce a current flow at the inductance coil when the conductive fluid flows through the tubular member, the flow of current being enhanced by the conductivity of the conductive fluid.