High-voltage X-ray generator

• US 20090009918A1
• Filed: 05/18/2008
• Published: 01/08/2009
• Est. Priority Date: 11/10/1999
• Status: Active Grant

• Current Assignee: Robert Beland
• Original Assignee: Robert Beland
• Inventors: Beland, Robert
• Granted Patent: US 7,936,544 B2
• Time in Patent Office: Days
• 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

1-62. -62. (canceled)

63. A shielded resistor circuit comprising:

a resistor mechanism having opposing end terminals; and

a shield for limiting electrical noise from interfering with the operation of the resistor mechanism, the shield including;

a plurality of paired conductive members disposed along the length of the resistor mechanism and having opposing end terminals, the pairs of conductive members separating the resistor mechanism into separate portions by providing alternating first and second pairs of conductive members along the length of the resistor mechanism;

a capacitor series comprising a plurality of serially connected capacitor mechanisms disposed a predetermined distance from the resistor mechanism and having opposing end terminals, each capacitor mechanism being connected between adjacent first and second pairs of conductive members being connected to the end terminals of the capacitor series, and the dynamic impedance of the capacitor series being less than the dynamic impedance of the resister mechanism;

a diode bridge series comprising a plurality of connected diode bridges coupled to the capacitor series;

wherein when the end terminals of the resistor mechanism are connected between a higher-voltage potential and a lower voltage potential, and the end terminals of the capacitor series are connected between the higher-voltage potential and ground, electrical noise is coupled to the capacitor series and does not interfere with the resistor mechanism.

64. The circuit as claimed in claim 63, further comprising an inductor mechanism intercoupled with said capacitor mechanism for limiting the rate of change of a transient voltage to a predetermined value.

65. The circuit as claimed in claim 64, wherein the inductor mechanism is a series of serially connected resistor mechanisms, the resistor mechanisms having a stray inductance.

66. The circuit as claimed in claim 64, wherein the diode bridges are serially connected, each of the diode mechanisms being connected in parallel with one of the capacitor mechanisms for preventing the voltage across the resistor mechanism from reversing polarity.

67. The circuit as claimed in claim 63, wherein each diode bridge has 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.

68. The circuit as claimed in claim 67 wherein the AC inputs to the AC source are through the capacitor series.

69. A shielded resistor circuit comprising:

a first insulating sheet and a second insulating sheet each having opposing inner and outer faces, the sheets being disposed in parallel with their inner faces adjacent one another, a resistor mechanism disposed between the inner faces;

a first series of paired conductive members disposed adjacent the resistor mechanism, each pair of the first series comprising a first member disposed on one of the inner faces and a second member disposed on the outer face opposing the other inner face, and means for connecting the first and second members;

a second series of paired conductive members disposed adjacent the resistor mechanism, each pair of the second series comprising a third member disposed on the outer face opposing the one inner face and a fourth member disposed on the other inner face, and means for connecting the third and fourth members, each pair of the second series being disposed between two pairs of the first series, the combined first and second series having opposing end terminals;

a capacitor series comprising a plurality of serially connected capacitor mechanisms disposed between the inner faces a predetermined distance from the resistor mechanism and having opposing end terminals, each capacitor mechanism being connected to an adjacent pair of the first series and pair of the second series, the end terminals of the conductive members being connected to the end terminals of the capacitor series, and the dynamic impedance of the capacitor series being less than the dynamic impedance of the resistor mechanism;

a diode bridge series comprising a plurality of connected diode bridges coupled to the capacitor series;

wherein the end terminals of the resistor mechanism are connected between a higher-voltage potential and a lower-voltage potential, and the end terminals of the capacitor series are connected between the higher-voltage potential and ground, electrical noise is coupled to the capacitor series and does not interfere with the resistor mechanism,

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

an X-ray generating source;

a regulator circuit which receives an input signal and regulates at least one of a duration and an amplitude of the input signal to produce a high-voltage output signal for operating the X-ray generating source; and

a protection circuit disposed between the regulator circuit and the X-ray generating source for limiting a rate of change of a transient voltage spike produced at the source to a predetermined value and protecting the regulator circuit, wherein the protection circuit comprises a plurality of series connected resistor mechanisms coupled to the source of the transient high-voltage spike, the resistor mechanisms having a stray inductance.

71. The apparatus of claim 70, wherein the resistor mechanisms are intercoupled with a high-voltage clamping mechanism.

72. The apparatus of claim 71, wherein the high-voltage clamping mechanism comprises a plurality of series connected voltage-limiting devices in parallel with the resistor mechanisms.

73. The apparatus of claim 72, wherein the voltage limiting devices comprise solid-state current conducting devices.

74. The apparatus of claim 70, wherein the protection circuit further comprises means for preventing the high-voltage spike from reversing polarity.

75. The apparatus of claim 74, wherein the preventing means includes a diode mechanism for preventing a voltage across the regulator circuit from reversing polarity.

76. The apparatus of claim 75, wherein the preventing means further includes at least one voltage limiting device connected in parallel with the diode mechanism.

77. The apparatus of claim 75, wherein the diode mechanism comprises a plurality of series connected diode bridges.

78. The apparatus of claim 77, wherein the plurality of diode bridges are four-diode bridges.

79. The apparatus of claim 77, 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.

80. The apparatus of claim 79, wherein the parallel connections of the AC inputs to the AC source are through coupling voltage limiting devices.

81. The apparatus of claim 80, wherein at least one DC return resistor mechanism is provided across at least one of the coupling voltage limiting devices.

82. The apparatus of claim 70, wherein the protection circuit does not comprise a resonant circuit.

83-89. -89. (canceled)