JP5997553B2 - X-ray high voltage apparatus and control method thereof - Google Patents

Description

  The present invention relates to an inverter type X-ray high voltage apparatus that can cope with voltage fluctuations of a commercial power supply voltage.

  An X-ray CT apparatus and an X-ray imaging apparatus irradiate a subject with X-rays generated from an X-ray tube, and detect and image an X-ray dose transmitted through the subject. An X-ray high voltage device is used to apply a DC high voltage between the anode and cathode of the X-ray tube. The thermoelectrons generated by raising the temperature of the cathode are accelerated by a direct current high voltage, and collide with the anode to generate X-rays.

  There are various types of X-ray high-voltage devices depending on how high voltage is generated. In recent years, inverter-type X-ray high-voltage devices that are excellent in size and performance have become widespread. For example, as in Patent Document 1, an inverter-type X-ray high-voltage device takes in an AC voltage from a single-phase or three-phase commercial power source through an AC reactor, converts the AC voltage into a DC voltage, and boosts the voltage to a target voltage. . The converter circuit includes a plurality of diodes and switches (IGBT). The DC voltage output from the converter circuit is smoothed by a capacitor and input to the inverter circuit. The DC voltage is converted into an AC voltage having a frequency higher than the commercial frequency by an inverter circuit, and then boosted to a DC high voltage by a high voltage generator and applied between the anode and cathode of the X-ray tube as a load. The tube voltage is controlled by the inverter control circuit adjusting the switching phase difference, frequency or pulse width of the inverter circuit.

  As in Patent Document 1, a converter control circuit is connected to the converter circuit, and switches in the converter circuit are controlled so that the output voltage of the converter circuit is boosted to a target voltage. At this time, Patent Document 1 describes that the output voltage of the converter circuit is prevented from overshooting or dropping due to the load state of the converter circuit (X-ray exposure conditions, whether X-ray exposure is in progress, etc.). A technique for switching the control gain of a converter control circuit according to a load state is disclosed.

JP 2000-252094 A

  Patent Document 1 discloses that the control gain of the converter circuit is switched in accordance with the load state. However, the control gain set by switching is such that the power supply voltage supplied from the commercial power supply to the converter circuit is within a predetermined range. It is a control gain determined in advance. That is, when the commercial power supply voltage is 200 V, a control gain dedicated for 200 V is prepared in advance for each load state.

  In recent years, there have been increasing opportunities to install X-ray CT apparatuses and X-ray imaging apparatuses in countries and regions where power supply conditions are poor such as overseas and in remote islands and mountains in the country. When the power supply situation is bad, the commercial power supply voltage is not stable, and the voltage supplied to the X-ray high voltage apparatus varies. The inverter type X-ray high-voltage apparatus is designed to operate even in such a state as long as it is within the specified voltage fluctuation range (generally ± 10% of the commercial power supply voltage). However, even when the voltage fluctuates within that range (for example, the commercial power supply voltage fluctuates from 200 V to 180 V), the control gain of the converter circuit is set for a predetermined voltage (for example, 200 V). There is a possibility that it does not work in an optimal state. For example, if the supplied voltage and the set voltage at which the control gain operates optimally do not match, the input voltage / current waveform of the converter circuit may be distorted and the power factor may deteriorate. When the power factor deteriorates, the reactive power increases, so that the facility device having the commercial power supply voltage must be increased by the reactive power. Further, when the input voltage / current waveform is distorted, there is a possibility that abnormal noise is generated from the AC reactor. A power module such as a diode or IGBT used in a converter circuit also has a problem of increased loss when rectifying or switching a distorted input current.

  Even in regions where power supply conditions are stable, voltage fluctuation may occur when a plurality of medical devices that require high voltage are connected to a commercial power supply and operating simultaneously. In this case, the same problem as described above occurs even in a region where the power supply situation is stable.

  An object of the present invention is to provide an X-ray high-voltage apparatus capable of generating a high voltage stably and efficiently even when a voltage supplied from a commercial power supply fluctuates.

  In order to solve the above problem, the present invention acquires the magnitude of the voltage supplied from the commercial power supply to the rectifier booster circuit when all the plurality of switch circuits of the rectifier booster circuit are turned off. The control gain is switched accordingly.

  According to the present invention, even if the voltage of the commercial power supply fluctuates, it is possible to acquire the voltage and set the optimal control gain in the control circuit, and always keep the power factor of the X-ray high voltage device optimal. it can.

1 is a block diagram showing a circuit configuration of an X-ray high voltage apparatus according to Embodiment 1 of the present invention. The block diagram which shows the detailed structure of the gain control circuit part 11 of the X-ray high voltage apparatus of FIG. The flowchart which shows operation | movement of the direct-current power supply circuit control part 9 of the X-ray high-voltage apparatus of FIG. FIG. 4 is a graph showing changes in converter output voltage Vc during operation of FIG. 3. FIG. The block diagram which shows the circuit structure of the X-ray high voltage apparatus of Embodiment 2. FIG. Explanatory drawing which shows the determination method whether commercial power supply is 200V type | system | group or 400V type | system | group in Embodiment 3. FIG.

  In the X-ray high voltage apparatus of the present invention, a rectification booster circuit that rectifies and boosts a voltage supplied from a commercial power supply, an inverter circuit that converts the output of the rectification booster circuit into an AC voltage, and a rectifier that controls the rectification booster circuit And a boost control circuit. The rectification booster circuit includes a plurality of switch circuits and a plurality of rectifier circuits, and the rectification booster control circuit outputs a signal for controlling operations of the plurality of switch circuits. The rectification boost control circuit acquires the magnitude of the voltage supplied from the commercial power supply to the rectification booster circuit when all of the plurality of switch circuits are turned off, and switches the control gain according to the acquired voltage magnitude.

  That is, the voltage input to the converter circuit from the commercial power supply is detected in the full-wave rectification state where all the switch circuits of the converter circuit (rectifier booster circuit) are off, and the converter circuit is operated according to the input voltage. The control gain of the converter circuit is switched. Furthermore, it is desirable to switch the control gain to a plurality of types depending on the load state when the switch circuit of the converter circuit is operating.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<Embodiment 1>
FIG. 1 is a block diagram of the overall configuration of the inverter type X-ray high voltage apparatus according to the first embodiment. This X-ray high voltage device includes an AC reactor 2, a converter circuit 3, a smoothing capacitor 4, a converter output voltage detector 5, an inverter circuit 6, a high voltage transformer 7, a rectifier 21, and an X-ray. A tube 8 and a DC power supply circuit control unit 9 are provided. With this configuration, the AC power supplied from the AC commercial power supply 1 is converted into DC by the converter circuit 3, smoothed by the smoothing capacitor 4, and then converted into a high-frequency AC voltage using the inverter circuit 6. The AC voltage output from the inverter circuit 6 is boosted by the high voltage transformer 7 and then rectified by the rectifier 21, and the DC high voltage is supplied to the X-ray tube 8 to emit X-rays.

  The converter circuit 3 has a structure in which three arms in which two switch circuits (insulated gate bipolar transistor IGBT) 31 connected in antiparallel with the diode 32 are connected in series are connected in parallel. The three-phase (U, V, W) power supply wiring of the commercial power supply 2 is connected between the two switch circuits 31 of the three arms via the AC reactor 2.

  The DC power supply circuit control unit 9 includes a gain control circuit unit 11, a main control unit 12, a gain table storage unit 22, and an input voltage detection unit 10 that detects an input voltage to the converter circuit 3.

  FIG. 2 shows a detailed configuration of the gain control circuit unit 11 and the main control unit 12. The gain control circuit unit 11 in this embodiment includes an output voltage regulator 23, an input current regulator 24, a pulse distributor 25, and a gain switching unit 14. The output voltage regulator 23 includes a first comparison unit 26, a proportional adjustment unit 28, and an integration adjustment unit 29. The input current regulator 24 includes second comparison units 27a and 27b and proportional adjustment units 30a and 30b.

  The gain switching unit 14 reads out and sets the control gain values (proportional gain Kp28, integral gain Ki29, proportional adjustment gains Kc30a, 30b) of the output voltage regulator 23 and the input current regulator 24 from the gain table storage unit 22. . In the present embodiment, the gain table storage unit 22 stores control gains (Kp, Ki) for each load state of the converter circuit 3 (status: during X-ray imaging preparation, X-ray exposure, X-ray exposure end, etc.). , Kc) (gain table) is prepared, and this set (gain table) is prepared in advance for each input voltage value (for example, 180 V, 190 V, 200 V, 210 V, 220 V) input to the converter circuit 3. Stored.

  The main control unit 12 outputs a gain table selection signal for designating a gain table to be used to the gain switching unit 14 before the converter circuit 3 is driven. The gain table selection signal is output by the main control unit 12 according to the value of the voltage input from the commercial power source 1 to the converter circuit 3. In addition, after the converter circuit 3 is driven, the main control unit 12 gains the load state of the converter circuit 3 (when preparing for X-ray exposure, when X-ray exposure is performed, when X-ray exposure is completed, etc.) as a status signal. The switching unit 14 is instructed. The gain switching unit 14 selects a gain table in accordance with the gain table selection signal, and sets a set of control gains (Kp, Ki, Kc) in the gain table to a load state (during X-ray imaging preparation, X-ray exposure) At the end of X-ray exposure, etc.) and set in the output voltage regulator 23 and the input current regulator 24.

  The functions of the gain control circuit unit 11 and the main control unit 12 can be realized by a program and a CPU that reads and executes the program.

  Hereinafter, the operation of each unit of the DC power supply circuit control unit 9 will be described with reference to the flowchart of FIG. First, when the power source of the X-ray high voltage apparatus is turned on by the operator and power is supplied to the DC power supply circuit control unit 9, the gain control circuit unit 11 and the main control unit 12 in the DC power supply circuit control unit 9 and the like. Then, communication with the input voltage detector 10, the converter circuit 3, the converter output voltage detector 5 and the like is started (steps 61 and 62).

  Next, the main control unit 12 instructs the gain control circuit unit 11 to turn off all the switch circuits (IGBTs) 31 of the converter circuit 3 (standby state: step 63). Thereby, in the converter circuit 3, all the switch circuits 31 are turned off, and only the three-phase full-wave rectification operation is performed.

The operator sets exposure conditions such as tube voltage, tube current, and exposure time, and instructs preparation for X-ray imaging. The main control unit 12 receives an X-ray imaging preparation instruction from the operator as an X-ray imaging preparation signal (step 64). The input voltage detection unit 10 detects input voltages (V _U , V _v , V _W ) of the converter circuit 3. The main control unit 12 generates a gain table selection signal for designating an optimum gain table (control gain set) according to the input voltage, and outputs the gain table selection signal to the gain control circuit unit 11 (step 65). For example, when the input voltage is 190 V, the main control unit 12 outputs a gain table selection signal for designating selection of a gain table for 190 V to the gain control circuit unit 11. At the same time, the main control unit 12 outputs a status signal indicating a load state (status) to the gain control circuit unit 11. In step 65, since X-ray imaging preparation is in progress, a status signal indicating that “X-ray imaging preparation is in progress” is output to the gain control circuit unit 11. Further, the main control unit 12 obtains the target voltage of the converter circuit 3 by calculation from the set tube voltage or the like, and outputs the target voltage signal Vr1 to the gain control circuit unit 11.

  The gain switching unit 14 of the gain control circuit unit 11 selects a gain table (for example, a gain table for 190V) specified by the gain table selection signal. Further, the gain switching unit 14 selects a set of control gains (Kp, Ki, Kc) are read out and set in the output voltage regulator 23 and the input current regulator 24 (step 66). The target voltage signal Vr1 output from the main control unit 12 is input to the output voltage regulator 23.

  As a result, the gain control circuit unit 11 generates signals for turning on and off the six switch circuits 31 of the converter circuit 3 as follows, and outputs the signals to the converter circuit 3 for control. The converter circuit 3 performs a boosting operation by turning on and off the switch circuit 31, and makes the output voltage Vc of the converter circuit 3 coincide with the target voltage signal Vr1 (step 67).

  Specifically, the target voltage signal Vr 1 is input to the first comparison unit 26 of the output voltage regulator 23 in the gain control circuit unit 11. At the same time, the actual output voltage Vc of the converter circuit 3 detected by the converter output voltage detector 5 is input to the first comparison unit 26, and the deviation from the target voltage signal Vr1 is calculated. The calculation result from the first comparison unit 26 is input to the proportional adjustment unit 28. The proportional adjustment unit 28 multiplies the deviation ecle generated by the comparison unit 26 by the proportional gain Kp, and adds a value obtained by multiplying the integral value of the deviation ecle by the integral gain Ki to obtain a current command ir.

  The input current regulator 24 matches the phase voltage and phase current of the AC power source to improve the power factor, and controls the phase current to a sine wave. The current command ir sent from the output voltage regulator 23 is inputted to the input current regulator 24, which is multiplied by sin (ωt) and sin (ωt−2π / 3), and each of the U phase and the V phase. Current commands iur, ivr are obtained. The comparators 27a and 27b obtain deviations iue and ive so that the phase currents iu and iv detected by the input current detectors 8a and 8b of the converter circuit 3 coincide with the current commands iur and ivr, and a proportional controller for the deviations. The current control amount is obtained by multiplying the gain Kc of 30. The control amount of the current thus obtained is sent to the pulse distributor 25, and a converter control signal S1 corresponding to the processing result is output. This converter control signal S1 determines the switching timing of each switch circuit 31 of the converter circuit 3 in accordance with the output voltage signal Vr1 of the target converter circuit. If the movement of two phases of the three-phase phase current is determined, the remaining one is inevitably determined. Therefore, only two of the three-phase input currents (U phase and V phase) are detected.

  Thus, when the converter circuit 3 receives power from the commercial power supply 1 and rectifies it, the converter circuit 3 can match the output voltage Vc with the target output voltage signal Vr1. In addition, the power factor can be increased by making the input current sinusoidal and not causing a phase delay.

  If the output voltage Vc of the converter circuit 3 coincides with the target output voltage signal Vr1, the main control unit 12 determines that the preparation for photographing has been completed, and notifies the operator of the completion of photographing preparation by display or the like (step 68).

  When the operator performs an operation for instructing the start of imaging, the inverter 6 operates to supply a tube voltage and a tube current to the X-ray tube 8 to emit X-rays. At this time, the main control unit 12 switches the status signal to a signal indicating “during X-ray exposure”. The gain switching unit 14 reads out a control gain pair (Kp, Ki, Kc) corresponding to “during X-ray exposure” from the control gain pair of the selected gain table, and outputs the voltage regulator 23 and the input current regulator 24 are set (step 69).

  When the X-ray exposure for a predetermined time is completed, the main control unit 12 switches the status signal to a signal indicating “end of X-ray exposure”. As a result, the gain switching unit 14 reads out the control gain set (Kp, Ki, Kc) corresponding to “X-ray exposure end” from the control gain set of the selected gain table and outputs it. The voltage regulator 23 and the input current regulator 24 are set (step 70).

  Thus, by switching the status signal for each period of “preparing for X-ray imaging”, “during X-ray exposure”, and “after X-ray exposure is completed”, the load state of the converter circuit 3 for each of these periods The control gain can be switched in response to a large change in. FIG. 4 shows changes in converter output voltage Vc during the operation of FIG. In the X-ray high voltage apparatus, the converter output voltage Vc changes greatly every time “preparing for X-ray imaging”, “during X-ray exposure”, and “after completion of X-ray exposure”, and the X-ray load range is very Widely, there is a large change of three orders of magnitude from hundreds of watts to 100 kW in the output power. In this embodiment, the drop or overshoot of the output voltage Vc of the converter circuit 3 is caused by switching the control gain according to the load state. Can be prevented.

  When the operator instructs to continue imaging 71 for the current patient, the main control unit 12 returns to step 68 and repeats X-ray exposure (step 71). Further, when the operator does not continue the imaging of the current patient, the operation shifts to the standby state, and similarly to step 63, all the switch circuits 31 of the converter circuit 3 are turned off to enter the full-wave rectification state.

  In this state, if the operator gives an instruction to image a new patient, the process returns to step 64 to prepare for X-ray imaging (step 73). Thereby, in step 64, the magnitude of the voltage of the commercial power source 1 is detected again, and an optimum gain table corresponding to the magnitude of the voltage is selected. If the operator does not instruct the imaging of a new patient, the power is turned off (step 74).

  As described above, in the present embodiment, the commercial power source applied to the X-ray high-voltage apparatus by detecting the input voltage in the above-described step 65 when all the switch circuits 31 of the converter circuit 3 are off. A voltage of 1 can be detected. Thereby, the optimal gain table according to the voltage value of the commercial power source 1 can be selected. In the gain table, a set of control gains can be selected according to the load state (status) and set in the gain control circuit unit 11.

  Therefore, even when the commercial power supply voltage applied to the X-ray high-voltage device fluctuates, it is possible to always select the optimal gain table and set the control gain. Can be kept optimal. Thereby, even in an area or a state where the voltage of the commercial power source is unstable, reactive power can be reduced and power use efficiency can be increased.

  Furthermore, since the control gain can be set according to the load state, it is possible to suppress the output voltage of the converter circuit from overshooting at the time of preparation for X-ray imaging and at the end of X-ray exposure. Moreover, it can suppress that the output voltage of a converter circuit falls at the time of X-ray exposure. By using the output voltage of such a converter circuit as the DC power supply voltage of the inverter circuit 6, the output of the inverter circuit 6 can be made to coincide well with the target tube voltage, and a tube voltage waveform without fluctuation can be obtained.

  In the first embodiment, an appropriate one of the gain tables stored in advance is selected according to the voltage of the AC power supply, and an appropriate set of control gains is read out from the gain table and set according to the load state. However, the present invention is not limited to this, and it is of course possible to obtain an appropriate control gain by calculation from the AC power supply voltage and the load state.

<Embodiment 2>
Next, the X-ray high voltage apparatus of Embodiment 2 is demonstrated using FIG. The X-ray high voltage apparatus of FIG. 5 is different from the X-ray high voltage apparatus described in Embodiment 1 in that the commercial power supply voltage is not detected by the input voltage detection unit 10. In the X-ray high voltage apparatus of FIG. 5, a bus voltage detection unit 13 is provided in the DC power supply circuit control unit 9 instead of the input voltage detection unit 10. Since other configurations are the same as those of the X-ray high voltage apparatus of the first embodiment, description thereof is omitted.

  The actual converter output voltage Vc of the converter circuit 3 output from the converter output voltage detector 5 is input to the bus voltage detector 13 of the DC power supply circuit controller 9. In step 65 of FIG. 3, the bus voltage detection unit 13 obtains a commercial power supply voltage from the converter output voltage Vc. That is, the voltage of the commercial power source 1 is obtained by calculation by dividing the converter output voltage Vc detected by the converter output voltage detector 5 by √2. For example, when the converter output voltage Vc is 283V, the voltage of the commercial power supply 1 is about 200V. When the converter output voltage Vc is 255V, the voltage of the commercial power source 1 is about 180V. The other operations of the DC power supply circuit control unit 9 are the same as those in the flow of FIG.

  Thereby, it is also possible to obtain the calculation from the converter output voltage Vc without detecting the input voltage from the commercial power source 1 to the converter circuit 3. Also in this case, the same effects as those of the first embodiment can be obtained.

  The processing for obtaining the voltage of the commercial power supply 1 by calculation in the bus voltage detection unit 13 can be performed by the main control unit 12.

<Embodiment 3>
The commercial power supply voltage connected to the X-ray high voltage apparatus is different in each country in the world, for example, 200V or 400V in Japan, 380V in China, and 208V or 480V in the United States. Broadly divided, it can be divided into 200V system (200V, 208V, 220V, 230V, 240V) and 400V system (380V, 400V, 415V, 440V, 480V).

  Therefore, in the third embodiment, the main control unit 12 determines whether the commercial voltage is the 200V system or the 400V system based on the magnitude of the voltage supplied from the commercial power supply 1 to the converter circuit 3, and switches the control gain. Note that a gain table group for a 200 V system (for voltage fluctuation around 200 V) and a gain table group for a 400 V system (for voltage fluctuation around 400 V) are stored in advance in the gain table storage unit 22.

  In the third embodiment, in step 65, the main control unit 12 first determines whether the voltage of the commercial power source 1 is 200V system or 400V system. FIG. 6 is a diagram showing voltage fluctuations in the 200V system and the 400V system. The minimum voltage of the 200V system is 180V when the commercial power supply voltage is changed by -10% when the commercial power supply voltage is 200V. On the other hand, the maximum voltage is 264V when the commercial power supply voltage is 240V and fluctuates by + 10%. The minimum voltage of the 400V system is 342V when the commercial power supply voltage is 380V and fluctuates by -10%. On the other hand, the maximum voltage is 528V when the commercial power supply voltage is changed by + 10% when the commercial power supply voltage is 480V. That is, if the voltage detected by the input voltage detection unit 10 shown in FIG. 1 is 300 V or less using a voltage between the maximum voltage 264 V of the 200 V system and the minimum voltage 342 V of the 400 V system, for example, 300 V as a discrimination reference voltage, the 200 V system If it is 300V or higher, it can be determined as a 400V system. Thereby, a gain table group of 200V system (for voltage fluctuation around 200V) or a gain table group of 400V system (for voltage fluctuation around 400V) can be selected.

  Thereafter, as in step 65 of FIG. 3, an optimum gain table is selected from the voltage detected by the input voltage detection unit 10. Other operations are the same as described with reference to the flow of FIG.

  Further, it is also possible to make a determination based on the voltage detected by the bus voltage detector 13 shown in FIG. That is, as shown in FIG. 6, the voltage detected by the bus voltage detector 13 in FIG. 5 is a voltage between the maximum bus voltage 373V of the 200V system and the minimum bus voltage 484V of the 400V system, for example, 430V. If it is 430 V or less, it can be discriminated as a 200 V system, and if it is 300 V or more, it can be discriminated as a 400 V system.

DESCRIPTION OF SYMBOLS 1 ... Commercial power source, 2 ... AC reactor, 3 ... Converter circuit, 4 ... Smoothing capacitor, 5 ... Converter output voltage detector, 6 ... Inverter circuit, 7 ... High voltage transformer, 8 ... X-ray tube, 9 ... DC Power supply circuit control unit, 10 ... input voltage detection unit, 11 ... gain control circuit unit, 12 ... main control unit, 13 ... bus voltage detection unit, 14 ... gain switching unit

Claims (9)

An X-ray having a rectification booster circuit that rectifies and boosts a voltage supplied from a commercial power supply, an inverter circuit that converts an output of the rectification booster circuit into an AC voltage, and a rectification booster control circuit that controls the rectifier booster circuit A high voltage device,
The rectifier booster circuit includes a plurality of switch circuits and a plurality of rectifier circuits,
The rectification boost control circuit includes:
Outputting a signal for controlling the operation of the plurality of switch circuits;
Obtaining a magnitude of a voltage supplied from the commercial power supply to the rectifying booster circuit in a state where all of the plurality of switch circuits are off, and switching a control gain according to the magnitude of the obtained voltage. X-ray high voltage device.   The X-ray high voltage apparatus according to claim 1, wherein the rectification boost control circuit switches the control gain according to a combination of the acquired commercial power supply voltage and a load state of the rectification boost circuit. An X-ray high voltage apparatus characterized by the above.   The X-ray high voltage apparatus according to claim 1, wherein the rectification boost control circuit detects the magnitude of the voltage in an input wiring for supplying a voltage from the commercial power source to the rectification boost circuit. X-ray high voltage device.   3. The X-ray high voltage apparatus according to claim 1, wherein the rectification boosting control circuit detects an output voltage from the rectification boosting circuit to the inverter circuit, and calculates the output voltage from the commercial power source. An X-ray high voltage apparatus characterized by obtaining a magnitude of a voltage supplied to a rectifying booster circuit. 3. The X-ray high-voltage apparatus according to claim 2, wherein the rectifying boost control circuit stores a gain table that stores a plurality of gain tables indicating the control gain for each load state for each voltage level of the commercial power supply. Part
Output a gain table selection signal that specifies the gain table according to the voltage of the commercial power supply, and output a status signal indicating the load state,
An X-ray high voltage apparatus, wherein a gain table is selected according to the gain table selection signal, and a control gain corresponding to the load state indicated by the status signal is read from the selected gain table and used.   The X-ray high-voltage apparatus according to claim 1, wherein the rectification boost control circuit detects a voltage level of the commercial power supply and switches the control gain for each X-ray imaging of different patients. X-ray high voltage device.   3. The X-ray high-voltage apparatus according to claim 2, wherein the rectification boost control circuit controls the load in three states as preparation for X-ray imaging, during X-ray exposure, and after completion of X-ray exposure. An X-ray high voltage apparatus characterized by switching a gain.   The X-ray high voltage apparatus according to claim 1, wherein the rectification boost control circuit determines whether the commercial voltage is a 200 V system or a 400 V system according to a voltage supplied from the commercial power source to the rectification boost circuit. An X-ray high voltage apparatus characterized by switching the control gain. An X-ray having a rectification booster circuit that rectifies and boosts a voltage supplied from a commercial power supply, an inverter circuit that converts an output of the rectification booster circuit into an AC voltage, and a rectification booster control circuit that controls the rectifier booster circuit A method of controlling a high voltage device,
With all the plurality of switch circuits of the rectifying booster circuit being in an off state, the magnitude of the voltage supplied from the commercial power source to the rectifying booster circuit is acquired,
A control method for an X-ray high voltage apparatus, wherein a control gain is switched according to the magnitude of the acquired voltage.

Images