A DEVICE AND A METHOD FOR DOWNHOLE ENERGY GENERATION

• US 20110049901A1
• Filed: 03/27/2009
• Published: 03/03/2011
• Est. Priority Date: 04/02/2008
• Status: Active Grant

• Current Assignee: Tendeka AS (Tendeka Oil & Gas Services Ltd.)
• Original Assignee: Tendeka AS (Tendeka Oil & Gas Services Ltd.)
• Inventors: Sørtveit, Håvar, Tinnen, Bård Martin
• Granted Patent: US 8,786,113 B2
• Time in Patent Office: Days
• US Class Current: 290/54
• CPC Class Codes: E21B 41/0085 Adaptations of electric power generating means for use in boreholes

Abstract

The present disclosure relates to a downhole electrical energy generating device (105) and a method for transforming energy from a fluid flow (107) passing the device (105), including: at least one vibrating assembly (250) influenced by the fluid flow (107) to oscillate, the vibrating assembly (250) including an elongated body (206) having a longitudinal axis being arranged non-parallel with the fluid flow (107), a stiff body (205) connecting the elongated body (206) to a portion of the device located downstream of said elongated body (206); at least one energy harvester (203) influenced by the vibrating assembly (250), wherein the energy generating device (105) is provided with means (204) for influencing the oscillation frequency of the vibrating assembly (250).

Claims

1-10. -10. (canceled)

11. A downhole electrical energy generating device for transforming energy from a fluid flow passing the device, comprising:

at least one vibrating assembly influenced by the fluid flow to oscillate, the vibrating assembly including an elongated body having a longitudinal axis being arranged non-parallel with the fluid flow, a stiff body connecting the elongated body to a portion of the device located downstream of said elongated body;

at least one energy harvester influenced by the vibrating assembly, wherein the energy generating device is provided with means for influencing the oscillation frequency of the vibrating assembly.

13. The device according to claim 11, wherein the means for influencing the oscillation frequency comprises a tuning device arranged for altering one or more characteristics of the downhole electrical energy generation device.

14. The device according to claim 11, wherein the tuning device comprises one of or a combination of two or more of:

means for changing the stiffness of the vibrating assembly;

means for changing a dominant oscillation mass of the vibrating assembly; and

/or

means for controlling the electric output from a generator.

15. The device according to claim 11, wherein the means for influencing the oscillation frequency comprises means for autonomous adjusting said frequency during operation.

16. The device according to claim 15, wherein the tuning device further comprises:

at least one sensor for sensing changes in energy levels of the vibrating assembly and/or energy produced by the harvester; and

at least one actuator controlled by a system controller, based on feedback from the sensor, to mechanically and/or electrically altering the characteristics of the vibrating assembly.

17. The device according to claim 11, wherein the stiff body is a rod extending into a sealed housing filled with a fluid, and wherein at least one energy harvester being arranged within said sealed housing.

18. The device according to claim 11, wherein the stiff body is a rod extending into a sealed housing filled with a fluid, and wherein at least one energy harvester being arranged in a portion of the elongated body.

19. The device according to claim 17, wherein the fluid is a gas.

20. The device according to claim 11, wherein the energy generating device is further provided with a pressure equalizing device arranged for adapting the pressure of the fluid within the housing to the surrounding pressure of the device.

12-1. The method according to claim 21, wherein the method further comprising providing the energy generating device with a pressure equalizing device arranged for adapting a fluid pressure within a portion of the device to a surrounding pressure of the device.

21. A method for optimising energy harvesting from a fluid flowing in a pipe, the method comprises the steps of arranging a downhole electrical energy generating device in the fluid flow, said device comprising at least one vibrating assembly influenced by the fluid flow, and at least one energy harvester influenced by the vibrating assembly, wherein the method further comprising providing the device with means for influencing the oscillation frequency of the vibrating assembly.

12. The device according to claim 11, wherein the elongated body is provided with at least one shield arranged for suppressing vortex shedding along a first direction of the elongated body, said first direction vortex shedding dampening desired vortex shedding along a second direction of the elongated body.