Rotationally symmetrical high-voltage pulse transformer with tesla resonance and energy recovery

• US 6,163,242 A
• Filed: 05/07/1999
• Issued: 12/19/2000
• Est. Priority Date: 05/07/1999
• Status: Active Grant

• Current Assignee: Scandinova Systems AB
• Original Assignee: Scanditronix Medical AB
• Inventors: Crewson, Walter Frederick John, Woodburn, David Kerr, Lindholm, Mikael Rolf
• Primary Examiner(s): Sterrett, Jeffrey
• Application Number:
  US09/306,728
• Time in Patent Office: 592 Days
• Field of Search: 336/145, 336/147, 336/182, 336/231, 363/20, 363/131
• US Class Current: 336/147
• CPC Class Codes: H01F 27/2847 Sheets; Strips H01F27/2866 takes precedence
• CPC Class Codes: H01F 30/08 without magnetic core
• CPC Class Codes: H05H 5/08 Particle accelerators using step-up transformers, e.g. resonance transformers

Abstract

A transformer of a Tesla type, and energy supply and particle accelerator devices that include such transformers. The electrical transformer includes a primary winding, a secondary winding which is electromagnetically coupled to the primary winding, and is characterized in that the primary winding consists of one single turn. The transformer operates without any soft magnetic core. The single turn is formed by at least two sector segments of a rotationally symmetric body, over which segments a voltage is applied. Preferably, the segments are equal in size, the voltages are equal in magnitude and one end of each segment is kept at ground potential. In an energy supply and an accelerator according to the present invention, a switch controlling the application of the voltage over the primary winding has controlled turn-on and turn-off preferably is an IGBT switch.

Claims

1. An electrical transformer comprising:

a primary winding, and

a secondary winding, electromagnetically coupled to said primary winding,

said primary winding consisting of one single turn and being formed by at least two sector segments of a rotationally symmetric body.

2. The electrical transformer according to claim 1, wherein said sector segments comprise electrical connections for applying a sector segment voltage between a first end and a second end, in circumferential direction, of each one of said sector segments.

3. The electrical transformer according to claim 2, wherein said sector segments are of equal size and said sector segment voltages are of equal magnitude.

4. The electrical transformer according to claim 3, wherein said first end of each one of said sector segments is kept at a common electric potential, whereby said first end of one sector segment is juxtaposed with said second end of another sector segment.

5. The electrical transformer according to claim 4, wherein said common electric is at ground potential.

6. The electrical transformer according to claim 1, wherein said sector segments are substantially sector segments of a hollow frustum of a cone.

7. The electrical transformer according to claim 1, wherein said electromagnetic coupling occurs in vacuum or a gas in the absence of a ferromagnetic core.

8. An energy supply device comprising a voltage supply, and a transformer having

a primary circuit having a primary winding and connected to said voltage supply, and a switching means controlling the application of a voltage of said voltage supply over said primary winding, said primary circuit having a resonant frequency,

a secondary circuit, having a secondary winding, electromagnetically coupled to said primary winding, said secondary circuit having the same resonant frequency as said primary circuit,

said primary winding consisting of one single turn, and being formed by at least two sector segments of a rotationally symmetric body, and

said switching means has controlled turn-on and turn-off.

9. The device according to claim 8, wherein said electromagnetic coupling between said primary winding and said secondary winding is selected substantially according to

10. The device according to claim 8, wherein said sector segments comprise electrical connections for applying a sector segment voltage between a first end and a second end, in circumferential direction, of each one of said sector segments.

11. The device according to claim 10, wherein said sector segments are of equal size, and said sector segment voltages are of equal magnitude.

12. The device according to claim 11, wherein said first end of each one of said sector segments is kept at a common electric potential, whereby said first end of one sector segment is juxtaposed with said second end of another sector segment.

13. The device according to claim 12, wherein said sector segment voltage is supplied by said voltage supply and in that said primary circuit comprises a number of switching means, having controlled turn-on and turn-off, each of said controlled switching means controls the application of said sector segment voltage to one of said sector segments.

14. The device according to claim 13, wherein said controlled switching means comprises an IGBT switch.

15. An electrodynamic accelerator device, comprising a voltage supply, a particle gun assembly, and a transformer having

a primary circuit having a primary winding and being connected to said voltage supply, and a switching means controlling the application of a voltage of said voltage supply over said primary winding, said primary circuit having a resonant frequency,

a secondary circuit, having a secondary winding, electromagnetically coupled to said primary winding, said secondary circuit having the same resonance frequency as said primary circuit and being electrically connected to said particle gun assembly,

said primary winding consisting of one single turn, and being formed by at least two sector segments of a rotationally symmetric body, and

said switching means has controlled turn-on and turn-off.

16. The device according to claim 15, wherein said electromagnetic coupling between said primary winding and said secondary winding is selected substantially according to

17. The device according to claim 15, wherein said sector segments comprise electrical connections for applying a sector segment voltage between a first end and a second end, in circumferential direction, of each one of said sector segments.

18. The device according to claim 17, wherein said sector segments are of equal size, and said sector segment voltages are of equal magnitude.

19. The device according to claim 18, wherein said first end of each one of said sector segments is kept at a common electric potential, whereby said first end of one sector segment is juxtaposed with said second end of another sector segment.

20. The device according to claim 19, wherein said sector segment voltage is supplied by said voltage supply arid in that said primary circuit comprises a number of switching means, having controlled turn-on and turn-off, each of said controlled switching means controls the application of said sector segment voltage to one of said sector segments.

21. The device according to claim 20, wherein said controlled switching means comprises an IGBT switch.

22. A method for producing electrical pulses with a voltage above 100 kV, comprising the steps of:

applying a primary voltage substantially simultaneously over each one of at least two sector segments of a primary winding, giving rise to a primary current;

producing an electromagnetic field through said primary winding;

inducing a secondary current in a secondary winding, by using electromagnetic coupling in vacuum or a gas in the absence of a ferromagnetic core, giving rise to a secondary voltage.

23. The method for producing electrical pulses according to claim 22, further comprising the step of connecting one end of each of said sector segments to a common potential.

24. The method for producing electrical pulses according to claim 23, wherein said common potential is ground potential.

25. The method for producing electrical pulses according to claim 22, wherein said primary voltage of each one of said sector segments are equal.

26. The method for producing electrical pulses according to claim 22, further comprising the step of tuning the resonance frequency of a primary circuit comprising said primary winding and the resonance frequency of a secondary circuit comprising said secondary winding to agree.

27. The method for producing electrical pulses according to claim 26, further comprising the step of tuning the electromagnetic coupling between said primary and secondary winding according to

28. The method for producing electrical pulses according to claim 26, further comprising the step of disconnecting said primary winding when said primary voltage is substantially zero.

29. The method for producing electrical pulses according to claim 28, further comprising the step of returning any energy not delivered to a particle beam or lost in heat to said primary circuit for use in a next pulse.

30. The method for producing electrical pulses according to claim 26, further comprising the step of disconnecting said primary winding when said secondary circuit contains an electric energy of substantially zero magnitude.

31. The method for producing electrical pulses according to claim 30, further comprising the step of returning any energy not delivered to a particle beam or lost in heat to said primary circuit for use in a next pulse.