High-voltage X-ray generator

• US 7,936,544 B2
• Filed: 05/18/2008
• Issued: 05/03/2011
• Est. Priority Date: 11/10/1999
• Status: Expired due to Term

• Current Assignee: EMD Technologies Inc (Benchmark Electronics Incorporated)
• Original Assignee: EMD Technologies Inc (Benchmark Electronics Incorporated)
• Inventors: Beland, Robert
• Primary Examiner(s): Fureman; Jared J
• Assistant Examiner(s): BAUER, SCOTT ALLEN
• Application Number:
  US12/154,013
• Publication Number:
  US 20090009918A1
• Time in Patent Office: 1,080 Days
• Field of Search: 361/58, 378101-118
• US Class Current: 361/58
• CPC Class Codes: H02M 1/0077 Plural converter units whose outputs are connected in series
• CPC Class Codes: H02M 1/088 for the simultaneous control of series or parallel connected semiconductor devices
• CPC Class Codes: H02M 3/3376 with automatic control of output voltage or current
• CPC Class Codes: H02M 7/003 Constructional details, e.g. physical layout, assembly, wiring or busbar connections
• CPC Class Codes: H02M 7/49 Combination of the output voltage waveforms of a plurality of converters
• CPC Class Codes: H05G 1/10 Power supply arrangements for feeding the X-ray tube supply circuits with converters in general H02M; supply circuits for emitters and amplifiers H04B1/16 - H04B1/1623
• CPC Class Codes: H05G 1/12 with dc or rectified single-phase ac or double-phase
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
• CPC Class Codes: Y10T 29/49071 by winding or coiling

Abstract

A power supply for a device which has a load, comprising a first resonant generator and a second resonant generator, coupled in parallel, each generator having a phase output. The power supply further comprises a control circuit coupled to the first and second generators controlling the first and second phase outputs, wherein the first phase output and the second phase output are summed to provide a variable power supply to the load.

Claims

1. An X-ray generating source and regulated power supply comprising:

an X-ray generating source;

a regulator circuit which receives input high-frequency, medium-voltage signals having regulated at least one of a duration and an amplitude of the input signals and produces a summed output signal having a selected power based on said duration and said amplitude, said selected power being employed for operating the X-ray generating source; and

a protection circuit constructed and arranged for the X-ray generating source and constructed to limit a rate of change of a transient voltage spike produced at the X-ray generating source to a predetermined value, wherein the protection circuit comprises a plurality of series connected resistor mechanisms located at a high-voltage module providing high-voltage to the X-ray generating source, the resistor mechanisms having plurality of resistors connected in series and an equivalent inductor designed to prolong a rise time of the transient high-voltage spike.

2. The apparatus of claim 1, wherein the resistor mechanisms are intercoupled with a high-voltage clamping mechanism.

3. The apparatus of claim 2, wherein the high-voltage clamping mechanism comprises a plurality of series connected voltage-limiting devices in parallel with the resistor mechanisms.

4. The apparatus of claim 3, wherein the voltage limiting devices comprise solid-state current conducting devices.

5. The apparatus of claim 1, wherein the protection circuit further comprises means for preventing the high-voltage spike from reversing polarity.

6. The apparatus of claim 5, wherein the preventing means includes a diode mechanism for preventing a voltage across the regulator circuit from reversing polarity.

7. The apparatus of claim 6, wherein the preventing means further includes at least one voltage limiting device connected in parallel with the diode mechanism.

8. The apparatus of claim 6, wherein the diode mechanism comprises a plurality of series connected diode bridges.

9. The apparatus of claim 8, wherein the plurality of diode bridges are four-diode bridges.

10. The apparatus of claim 8, wherein the plurality of diode bridges have a DC output and an AC input, wherein the DC outputs are connected in series and the AC inputs are connected in parallel to an AC source.

11. The apparatus of claim 10, wherein the parallel connections of the AC inputs to the AC source are through coupling voltage limiting devices.

12. The apparatus of claim 11, wherein at least one DC return resistor mechanism is provided across at least one of the coupling voltage limiting devices.

13. The apparatus of claim 1, wherein the protection circuit does not comprise a resonant circuit.

14. The apparatus of claim 1, wherein the X-ray generating source provides X-ray radiation for pulsed fluoroscopy.

15. The apparatus of claim 1, wherein the X-ray generating source provides X-ray radiation for computed tomography scans.

16. An X-ray generating source and regulated power supply comprising:

an X-ray generating source;

a regulator circuit which receives medium-voltage high-frequency input signals each having a controlled phase and each having a power provided in a resonant arrangement to a transformer constructed and arranged to sum said input signals in a load sharing way for providing a combined output signal of selected power, said selected power being employed for operating the X-ray generating source; and

a protection circuit coupled to the X-ray generating source for limiting a rate of change of a transient voltage spike produced at the X-ray generating source to a predetermined value, wherein the protection circuit comprises a plurality of series connected resistor mechanisms at a high-voltage module providing high-voltage to the X-ray generating source, the resistor mechanisms having plurality of resistors connected in series and an equivalent inductor designed to prolong a rise time of the transient high-voltage spike.

17. The apparatus of claim 16, wherein the resistor mechanisms are intercoupled with a high-voltage clamping mechanism.

18. The apparatus of claim 17, wherein the high-voltage clamping mechanism comprises a plurality of series connected voltage-limiting devices in parallel with the resistor mechanisms.

19. The apparatus of claim 18, wherein the voltage limiting devices comprise solid-state current conducting devices.

20. The apparatus of claim 16, wherein the protection circuit further comprises several diode bridges.

21. The apparatus of claim 20, wherein the several diode bridges have a DC output and an AC input, wherein the DC outputs are connected in series and the AC inputs are connected in parallel to voltage limiting devices.

22. The apparatus of claim 16, wherein the X-ray generating source provides X-ray radiation for pulsed fluoroscopy.

23. The apparatus of claim 16, wherein the X-ray generating source provides X-ray radiation for computed tomography scans.

24. An X-ray generating source and regulated power supply comprising:

an X-ray generating source;

a regulator circuit constructed to regulate relative phase of several medium-voltage high-frequency signals being magnetically coupled using a transformer having several coils constructed and arranged to add said medium-voltage high-frequency signals in a load sharing way to provide a combined output signal having power selected for operating the X-ray generating source; and

a protection circuit designed for the X-ray generating source for limiting a rate of change of a transient voltage spike produced at the X-ray generating source to a predetermined value, wherein the protection circuit comprises a plurality of series connected resistors located at a high-voltage module providing high-voltage to the X-ray generating source and having a stray inductance to function as an equivalent inductor designed to prolong a rise time of the transient high-voltage spike and to prevent resonance between a high-voltage cable and an equivalent capacitance of a high voltage generator.

25. The apparatus of claim 24 further including a plurality of series connected voltage-limiting devices in parallel with said resistors.

26. The apparatus of claim 25, wherein said voltage limiting devices comprise solid-state current conducting devices.

27. The apparatus of claim 24, wherein the protection circuit further comprises several diode bridges.

28. The apparatus of claim 24, wherein the X-ray generating source provides X-ray radiation for pulsed fluoroscopy.

29. The apparatus of claim 24, wherein the X-ray generating source provides X-ray radiation for computed tomography scans.