SYSTEMS AND METHODS FOR REDUCING UNDESIRED EDDY CURRENTS

• US 20180323007A1
• Filed: 11/09/2017
• Published: 11/08/2018
• Est. Priority Date: 05/12/2015
• Status: Active Grant

• Current Assignee: Tae Technologies, Inc.
• Original Assignee: Tae Technologies, Inc.
• Inventors: Rath, Nikolaus
• Granted Patent: US 10,418,170 B2
• Time in Patent Office: Days
• CPC Class Codes: G21B 1/052 reversed field configuration
• CPC Class Codes: H01F 2027/348 Preventing eddy currents
• CPC Class Codes: H01F 27/34 Special means for preventing or reducing unwanted electric or magnetic effects, e.g. no-load losses, reactive currents, harmonics, oscillations, leakage fields
• CPC Class Codes: H05H 1/10 using externally-applied magnetic fields only , e.g. Q-machines, Yin-Yang, base-ball
• CPC Class Codes: Y02E 30/10 Nuclear fusion reactors

Abstract

Systems and methods to reduce the amplitude of undesirable eddy currents in conducting structures, e.g., induced by the translation of an FRC into a confinement chamber, while leaving beneficial eddy currents unaffected. This is achieved by inducing opposing currents in the same conducting structures prior to plasma translation into the confinement chamber.

Claims

1. A method for reducing undesired eddy currents induced in a conducting structure, the method comprising the steps of:

inducing a first set of eddy currents in a conducting prior to inducing a second set of eddy currents in the conducting structure, wherein the first set of eddy currents having a distribution substantial equal to and opposite in sign to the distribution of the second set of eddy currents to substantial cancel the second set of eddy currents upon inducement of the second set of eddy currents in the conducting structure.

2. The method of claim 1 wherein the conducting structure is a wall of a plasma confinement vessel.

3. The method of claim 1 wherein the step of inducing eddy currents in a conducting structure includes the steps of

ramping up and holding coils about the conducting structure at a constant current until all eddy currents have decayed in the conducting structure, and

interrupting current to the coils to allow the first set of eddy currents to excite in the conducting structures conserving the magnetic flux through the structures.

4. The method of claim 1 further comprising the step of translating a plasma into the conducting structure, wherein the translating plasma injects a flux into the conducting structure that induces the second set of eddy currents in the wall of the vessel reducing the amplitude of eddy currents in the wall of the vessel back towards zero.

5. The method of claim 3 further comprising the step of translating a plasma into the conducting structure, wherein the translating plasma injects a flux into the conducting structure that induces the second set of eddy currents in the wall of the vessel reducing the amplitude of eddy currents in the wall of the vessel back towards zero.

6. The method of claim 1 wherein the step of inducing eddy currents in a conducting structure includes the steps of

ramping up and holding coils about the conducting structure at a constant current to produce the first set of eddy currents in the conducting structure, and

translating a plasma into the conducting structure, wherein the translating plasma injects a flux into the conducting structure that induces the second set of eddy currents in the conducting structure reducing the amplitude of eddy currents in the conducting structure back towards zero.

7. A system for reducing undesired eddy currents induced in a vessel wall, the system comprising:

a vessel having a wall and an interior,

a plurality coils positioned around the vessel, and

a control system coupled to the plurality of coils and configured to induce a first set of eddy currents in the wall of the vessel prior to a second set of eddy currents being induced in the wall of the vessel, wherein the first set of eddy currents having a distribution substantial equal to and opposite in sign to the distribution of the second set of eddy currents to substantial cancel the second set of eddy currents upon inducement of the second set of eddy currents in the wall of the chamber.

8. The system of claim 7 wherein the control system is further configured to ramp up and hold the plurality of coils at a constant current until all eddy currents in the wall of the vessel have decayed, and then interrupt the current to the plurality of coils to allow the first set of eddy currents to excite in the wall of the vessel conserving the flux through the vessel.

9. The system of claim 8 further comprising a formation section attached to an end of the vessel, wherein the control system is further configured to translate a plasma from the formation section into the interior of the vessel, wherein the translating plasma injects a flux into the wall of the vessel that induces the second set of eddy currents in the wall of the vessel reducing the amplitude of eddy currents in the wall of the vessel back towards zero.

10. The system of claim 7 wherein the control system is further configured to ramp up and hold the plurality of coils at a constant current to produce the first set of eddy currents in the conducting structure.

11. The system of claim 10 further comprising a formation section attached to an end of the vessel, wherein the control system is further configured to translate a plasma from the formation section into the interior of the vessel, wherein the translating plasma injects a flux into the wall of the vessel that induces the second set of eddy currents in the wall of the vessel reducing the amplitude of eddy currents in the wall of the vessel back towards zero.

12. A method for reducing undesired eddy currents induced in a conducting structure, the method comprising the steps of:

inducing a first set of eddy currents in a wall of a vessel having a wall and an interior prior to inducing a second set of eddy currents in the wall of the vessel, wherein the first set of eddy currents having a distribution substantial equal to and opposite in sign to the distribution of the second set of eddy currents to substantial cancel the second set of eddy currents upon inducement of the second set of eddy currents in the conducting structure.

13. The method of claim 12 wherein the step of inducing eddy currents in the wall of the vessel includes the steps of

ramping up and holding a plurality of coils positioned about the wall of the vessel at a constant current until all eddy currents have decayed in the conducting structure, and

interrupting current to the plurality of coils to allow the first set of eddy currents to excite in the wall of the vessel conserving the magnetic flux through the wall of the vessel.

14. The method of claim 12 further comprising the step of translating a plasma into the vessel, wherein the translating plasma injects a flux into the wall of the vessels that induces the second set of eddy currents in the wall of the vessel reducing the amplitude of eddy currents in the wall of the vessel back towards zero.

15. The method of claim 13 further comprising the step of translating a plasma into the vessel, wherein the translating plasma injects a flux into the wall of the vessels that induces the second set of eddy currents in the wall of the vessel reducing the amplitude of eddy currents in the wall of the vessel back towards zero.

16. The method of claim 13 wherein the plasma is translated from opposing formation sections attached to opposite ends of the vessel.

17. The method of claim 16, wherein an FRC plasma is formed in the opposing formation sections and translated into the vessel.

18. The method of claim 12 wherein the step of inducing eddy currents in the wall of the vessel includes the steps of

ramping up and holding a plurality of coils positioned about the wall of the vessel at a constant current to produce the first set of eddy currents in the wall of the vessel, and

translating a plasma into the vessel, wherein the translating plasma injects a flux into the wall of the vessel that induces the second set of eddy currents in the wall of the vessel reducing the amplitude of eddy currents in the wall of the vessel back towards zero.

19. The method of claim 18 wherein the plasma is translated from opposing formation sections attached to opposite ends of the vessel.

20. The method of claim 19, wherein an FRC plasma is formed in the opposing formation sections and translated into the vessel.