Apparatus and Method for Controlling Arc in X-ray Tube

Abstract

The present invention relates to an apparatus and method for controlling an arc detected in an X-ray tube so as to enable a rapid response when an arc occurs. An arc control device in an X-ray tube according to an embodiment of the present invention includes an arc current sensing unit that senses an arc generated in an X-ray tube and measures an arc current value; a voltage changing unit that changes the measured current value into a voltage using centripetal resistors (R1) and (R2); a voltage amplification unit that amplifies the voltage value changed by the voltage changing unit using a non-inverting amplifier; a comparison unit that monitors the amplified voltage and transmits an arc-detecting (ARCING_DET) signal indicating that an arc has occurred through a photocoupler when the voltage is greater than or equal to a preset reference voltage; a signal transmission unit that outputs a blocking signal by converting the input arc-detecting signal to low to block the output signal; and an output signal generation unit that blocks the final output by operating a signal blocking MOSFET connected between the main MOSFET gate signal and GND using the blocking signal as input.

Description

Technology Field

[0001] The present invention relates to an apparatus and method for controlling an arc detected in an X-ray tube so as to enable a rapid response when an arc occurs. Background Technology

[0003] Generally, an X-ray generator consists of a cathode that generates an electron beam and an anode that generates X-rays when the electron beam from the cathode collides with it with high kinetic energy. In other words, the output of an X-ray generator is proportional to the current of the electron beam coming from the cathode (tube current) and the voltage applied between the cathode and the anode (tube voltage).

[0004] At this time, a target made of a metal material with a high atomic number, such as tungsten, molybdenum, or copper, is formed at the anode, and electrons striking the target emit X-ray radiation as they undergo acceleration due to electromagnetic interactions with the target atoms. Alternatively, X-rays are generated by exchanging momentum and energy with electrons striking the target, and then emitting electromagnetic radiation corresponding to the energy difference between the excited state and the ground state when returning to the ground state.

[0005] In a typical X-ray generator, the cathode is composed of a tungsten filament or a negative electrode heated by a tungsten filament, so ion bombardment does not significantly affect the electron beam emission performance or lifespan of the negative electrode. However, in a field-effect cathode with a nanometer-scale microstructure, ion bombardment can affect the shape and structure of the field emission tip, thereby reducing the lifespan and performance of the negative electrode. Additionally, the generation of secondary or tertiary electrons due to ion sputtering can cause over-emission of electrons, leading to overcurrent, or metal ions emitted by sputtering can accumulate on the surface of an insulator, reducing insulation performance, thereby causing permanent damage to the field emission device.

[0006] To resolve this problem, the system is configured to sense the arc current generated in the X-ray tube, detect rapid changes in current, and convert this into a signal, enabling safe use in high-voltage systems.

[0007] Methods for sensing arc current include 1) a method using a shunt resistor, 2) a method using a current transformer (CT), 3) a method using a Hall effect sensor, 4) an arc detection method using an optical sensor, and 5) a high-speed digital signal processing (DSP) method.

[0008] 1) The method using a sensing resistor is the simplest way to sense the current flowing through an X-ray tube. By using a sensing resistor, the arc current is sensed by detecting the voltage across the sensing resistor that occurs in proportion to the current when the current flowing through the X-ray tube passes through the sensing resistor.

[0009] To explain in more detail, the sensing resistor has a very small value (typically in the milliohm range) and therefore does not significantly affect the flow of current in the circuit. When an arc occurs, the current increases rapidly, and the voltage across the resistor surges accordingly. This voltage is detected and converted into an analog signal, which is then amplified or transmitted to the control system via a comparator circuit. Through this method, arc current can be detected simply and inexpensively.

[0010] However, this method has the disadvantage that the sensing resistor itself can generate heat and requires additional insulation design in very high-voltage environments.

[0011] 2) The method using a current converter is a method of indirectly measuring the current of an X-ray tube using a current converter. Unlike a sensing resistor, this method is not inserted directly into the circuit but measures using the magnetic field of the current.

[0012] To explain in more detail, when current flowing through an X-ray tube passes through a wire, a magnetic field is formed around the wire. The current transducer detects this magnetic field and generates an induced current in the secondary coil. This induced current is proportional to the current in the X-ray tube. Therefore, if an arc occurs and the current increases rapidly, the output current of the current transducer also surges; this is detected to monitor the change in current. Through this method, current can be measured without direct contact, allowing for safe use in high-voltage systems.

[0013] However, this method has the disadvantage of requiring a relatively complex design and the setting of an appropriate transformer ratio for accurate measurement.

[0014] 3) The method using a Hall effect sensor is a method of indirectly detecting current by measuring the magnetic field generated when current flows using a Hall effect sensor.

[0015] To explain in more detail, when the magnetic field formed by the current flowing through the X-ray tube is detected by the Hall effect sensor, a voltage is generated in the sensor due to the Hall effect. This voltage is proportional to the magnitude of the current; when an arc current occurs, the current increases rapidly, causing the sensor output voltage to change abruptly as well. Through this change, the arc current is detected and transmitted to the control system. This method allows for non-contact current detection and enables use in high-voltage and high-current environments.

[0016] However, this method may have lower sensitivity than current converters and has the disadvantage of requiring additional correction depending on the system design.

[0017] 4) The arc detection method using optical sensors allows for the detection of arcs occurring inside the X-ray tube under specific conditions, even though the arc is invisible. Through this, the arc current is sensed. This method primarily detects the arc itself as an optical signal rather than as a current.

[0018] To explain in more detail, when an arc occurs, a plasma discharge is generated due to high voltage and current, which can produce light. Optical sensors detect this light and can indirectly determine that an arc current has occurred by analyzing the sensitivity and pattern of the light. Through this method, an arc can be detected using physical characteristics different from current or voltage.

[0019] However, since light is not generated from every arc, this method can only be used under specific conditions, and it has the disadvantage that its accuracy may be lower compared to other methods.

[0020] 5), the high-speed digital signal processing method can detect arc current by analyzing changes in current or voltage signals in real time through high-speed digital signal processing technology.

[0021] To explain in more detail, rapid fluctuations occur in current or voltage signals when an arc current is generated; these fluctuations are digitized to analyze patterns. Then, a high-speed DSP is used to determine whether these signal changes are caused by an arc, and an immediate control signal is generated. Through this method, complex signal analysis is possible, and more accurate arc detection is enabled by analyzing various patterns.

[0022] However, this method requires high-speed processors and complex algorithms, and has the disadvantage that the system design can become complex. Prior art literature

[0024] Korean Registered Patent Publication No. 10-2515761 (Registered on March 27, 2023) Korean Published Patent Publication No. 10-2008-0090212 (Published on October 8, 2008) The problem to be solved

[0025] The present invention aims to provide an apparatus and method for controlling an arc detected in an X-ray tube so as to enable a rapid response when an arc occurs.

[0026] The present invention aims to provide an arc control device and method for an X-ray tube that enables a very fast and immediate response by detecting and controlling an arc in microsecond (us) units, thereby protecting the equipment by rapidly interrupting the current. means of solving the problem

[0028] An arc control device in an X-ray tube according to an embodiment of the present invention includes an arc current sensing unit that senses an arc generated in an X-ray tube and measures an arc current value; a voltage changing unit that changes the measured current value into a voltage using centripetal resistors (R1) and (R2); a voltage amplification unit that amplifies the voltage value changed by the voltage changing unit using a non-inverting amplifier; a comparison unit that monitors the amplified voltage and transmits an arc-detecting (ARCING_DET) signal indicating that an arc has occurred through a photocoupler when the voltage is greater than or equal to a preset reference voltage; a signal transmission unit that outputs a blocking signal by converting the input arc-detecting signal to low to block the output signal; and an output signal generation unit that blocks the final output by operating a signal blocking MOSFET connected between the main MOSFET gate signal and GND using the blocking signal as input.

[0029] The arc control device in the above X-ray tube monitors the measured current value through the voltage changed in the voltage changing unit.

[0030] The output signal generating unit above operates the MOSFET within a time of several microseconds (μs) or less through the blocking signal to switch the main switching unit, thereby blocking the final output.

[0031] The above voltage amplification unit and comparison unit are characterized by implementing an arc control circuit using an analog method utilizing a comparator or amplifier.

[0032] The arc control device in the X-ray tube above further includes a control unit that generates a control signal using the blocking signal and outputs it to the output signal generating unit, thereby controlling the output of the main switching unit to be blocked first.

[0033] The above control unit controls the secondary blocking of the output signal to be performed simultaneously with the primary blocking using the control CPU and the main system.

[0034] An arc control method in an X-ray tube according to an embodiment of the present invention comprises: a current measurement step in which an arc generated in an X-ray tube is sensed and an arc current value is measured in an arc current sensing unit; a voltage amplification step in which the measured current value is changed into a voltage using centripetal resistors (R1) and (R2) in a voltage changing unit, and the changed voltage value is amplified using a non-inverting amplifier; a voltage abnormality detection step in which the amplified voltage is monitored in a comparison unit, and if it is above a preset reference voltage, an arc-detecting (ARCING_DET) signal is transmitted through a photocoupler to indicate that an arc has occurred; a blocking signal output step in which the arc-detecting signal is converted to low and output as a blocking signal to block the output signal in a signal transmission unit; and a main MOSFET control step in which the operation of a signal blocking MOSFET connected between a main MOSFET gate signal and GND is controlled using the blocking signal to block the main switching unit.

[0035] The above current measurement step is characterized by detecting whether the current increases instantaneously upon X-ray irradiation.

[0036] The above voltage amplification step includes a step of monitoring the current value measured through the changed voltage.

[0037] The above main MOSFET control step operates the MOSFET within a time of several microseconds (μs) or less through the cutoff signal to switch the main switching unit, thereby cutting off the final output.

[0038] The arc control method in the X-ray tube described above further includes a first control step of generating a control signal using the blocking signal and outputting it to the output signal generating unit to control the output of the main switching unit to be blocked first.

[0039] The above first control step includes a second control step that controls the second blocking of the output signal to be performed using the control CPU and the main system simultaneously with the first blocking. Effects of the invention

[0041] According to an embodiment of the present invention, the following effects can be produced.

[0042] First, it can protect the equipment.

[0043] In other words, an arc is an unstable electrical discharge phenomenon occurring within an X-ray tube. This arc causes high current and voltage fluctuations, which can damage the X-ray tube and related circuits. Therefore, the present invention enables the detection and rapid control of arcs, thereby preventing serious damage to X-ray equipment and preventing a shortened equipment lifespan and increased repair costs.

[0044] Second, safety can be guaranteed.

[0045] In other words, since X-ray equipment uses high voltage, the occurrence of an arc can pose a threat to the safety of surrounding equipment or workers. Therefore, the present invention can contribute to maintaining a safe operating environment by reducing electrical hazards through arc control, thereby preventing explosive fluctuations in current or voltage within the equipment.

[0046] Third, X-ray output quality can be maintained.

[0047] In other words, if an arc occurs, the X-ray output may become unstable. Since X-ray equipment must maintain a constant output to ensure the quality of inspection or diagnosis, it is very important to prevent irregular X-ray output through arc control. The present invention can maintain image quality and ensure diagnostic accuracy.

[0048] Fourth, it can prevent system damage and downtime.

[0049] In other words, the impact of an arc on equipment can cause the entire system to shut down, which can lead to severe downtime in critical operating environments such as hospitals or research laboratories. This invention can prevent this and enhance the continuity and reliability of the equipment.

[0050] As such, by detecting and controlling the arc, the present invention has the effect of extending the stability and lifespan of the equipment and maintaining safe operation and high-quality X-ray output. Brief explanation of the drawing

[0052] FIG. 1 is a block diagram showing the configuration of an arc control device in an X-ray tube according to an embodiment of the present invention. FIG. 2 is a circuit diagram showing the configuration of an arc control device in an X-ray tube according to an embodiment of the present invention. FIG. 3 is a flowchart illustrating an arc control method in an X-ray tube according to an embodiment of the present invention. Specific details for implementing the invention

[0053] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms, and the embodiments of the present invention are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention. To explain the invention in detail, the drawings may be exaggerated, and like reference numerals in the drawings refer to like elements.

[0054] FIG. 1 is a block diagram showing the configuration of an arc control device in an X-ray tube according to an embodiment of the present invention, and FIG. 2 is a circuit diagram showing the configuration of an arc control device in an X-ray tube according to an embodiment of the present invention.

[0055] Referring to FIGS. 1 and 2, an arc control device in an X-ray tube according to an embodiment of the present invention includes an arc current sensing unit (10), a voltage changing unit (20), a voltage amplification unit (30), a comparison unit (40), a signal transmission unit (50), a control unit (60), an output signal generating unit (70), and a main switching unit (80).

[0056] The arc current sensing unit (10) senses the arc generated in the X-ray tube during X-ray irradiation and measures the arc current value. Through this, the arc current sensing unit (10) can detect whether the current increases rapidly instantaneously during X-ray irradiation.

[0057] The voltage changer (20) converts the measured current value into a voltage using centimeter resistors (R1) and (R2). The system can monitor the measured current value through the converted voltage.

[0058] At this time, the cent resistors (R1) and (R2) are sensors for measuring AC / DC current, and the first resistor (R1) and the second resistor (R2) are connected in parallel to the line to which the measured current value is input, thereby measuring the voltage generated by the current.

[0059] The voltage amplification unit (30) amplifies the voltage value changed in the voltage changing unit (20) using a non-inverting amplifier.

[0060] At this time, the non-inverting amplifier is a circuit in which the output signal is output identically to the input signal, and the voltage amplified by the voltage amplifier (30) is directly applied to the non-inverting terminal (+) of the operational amplifier (31), and the resistor connected to the other terminal (-) is grounded.

[0061] The comparator (40) monitors the voltage amplified by the voltage amplifier (30), and if it is above a preset reference voltage, it transmits an arc-detecting (ARCING_DET) signal through the photocoupler (51). The arc-detecting signal is a signal indicating that an arc has occurred in the system.

[0062] The signal transmission unit (50) converts the input arc-detecting signal to low and outputs a blocking signal that blocks the output signal.

[0063] The output signal generation unit (70) receives the blocking signal output from the signal transmission unit (50) as input and operates the signal blocking MOSFET (71) connected between the main MOSFET gate signal and GND. That is, the output signal generation unit (70) connects the main MOSFET gate signal to GND and operates the MOSFET (71) within a short time (within a time of 1 microsecond (1μs) or less) through the blocking signal (low blocking signal) output from the signal transmission unit (50) to switch the main switching unit (80) and block the final output.

[0064] Thus, the arc control device in an X-ray tube according to an embodiment of the present invention can detect and control the arc in a very short time, that is, in microseconds (μs), by implementing an arc control circuit using an analog method that utilizes a comparator (41), an amplifier (31), etc.

[0065] That is, when an arc occurs, a sudden change in current or voltage occurs, and a sensing circuit and an analog circuit (comparator (41), amplifier (31), etc.) that detect this immediately react to operate a signal-blocking MOSFET (71) to cut off the power supply through the main switching unit (80).

[0066] Since the present invention processes electrical signals in real time in an analog circuit, when a sudden change in current is detected, there is almost no delay time, and the arc can be quickly cut off within a time of 1 microsecond (1 μs) or less as soon as it occurs.

[0067] Accordingly, the arc control device for an X-ray tube according to the present invention is suitable for high-speed systems that must prevent electrical accidents in an extremely short time. For example, it can immediately block an arc generated in high-voltage equipment such as an X-ray tube to prevent loss or overload of the tube.

[0068] Meanwhile, the control unit (60) generates a control signal using a blocking signal input from the signal transmission unit (50) and outputs it to the output signal generation unit (70), thereby controlling the output of the main switching unit (80) to be blocked first, and simultaneously controls the control CPU (91) and the main system (92) to perform a second blocking of the output signal.

[0069] At this time, the second blocking is performed after the main switching unit (80) is first blocked, and the output signal by the CPU (91) and the main system (92) is secondarily blocked, thereby preventing damage to the X-ray system more stably.

[0071] Hereinafter, an arc control method in an X-ray tube according to an embodiment of the present invention will be described. The arc control method in an X-ray tube according to an embodiment of the present invention may be a method for processing a received signal using the aforementioned arc control device in an X-ray tube, and since the aforementioned details regarding the arc control device in an X-ray tube can be applied as is, the description of redundant details may be omitted.

[0072] FIG. 3 is a flowchart illustrating an arc control method in an X-ray tube according to an embodiment of the present invention.

[0073] Referring to FIG. 3, an arc control method in an X-ray tube according to an embodiment of the present invention first detects an arc generated in the X-ray tube during X-ray irradiation by sensing an arc in an arc current sensing unit (10) and measures an arc current value (S10). Through this, the arc current sensing unit (10) can detect whether the current increases rapidly instantaneously during X-ray irradiation.

[0074] Next, in the voltage changing unit (20), the measured current value is converted into a voltage using centimeter resistors (R1) and (R2) (S20), and then the voltage value converted in the voltage changing unit (20) is amplified using a non-inverting amplifier (S30). At this time, the system can monitor the measured current value through the changing voltage.

[0075] Next, the comparison unit (40) monitors the amplified voltage, and if it is above a preset reference voltage, it transmits an arc-detecting (ARCING_DET) signal through the photocoupler (51) (S40). At this time, the arc-detecting signal is a signal indicating that an arc has occurred in the system.

[0076] Then, in the signal transmission unit (50), the input arc-detecting signal is converted to low and a blocking signal is output to block the output signal (S50).

[0077] Then, using the output blocking signal, the operation of the signal blocking MOSFET (71) connected between the main MOSFET gate signal and GND is controlled to block the main switching unit (80) (S60). That is, the main MOSFET gate signal is connected to GND, and the MOSFET (71) is operated within a short time (within a time of 1 microsecond (1μs) or less) through the blocking signal (low blocking signal) to switch the main switching unit (80) and block the final output (first blocking).

[0078] Then, in the control unit (60), a control signal is generated using the blocking signal input from the signal transmission unit (50) to control the secondary blocking of the output signal through the control CPU (91) and the main system (92) (S70).

[0079] At this time, the secondary blocking is performed by the CPU (91) and the main system (92) after the main switching unit (80) is blocked first, thereby preventing damage to the X-ray system more stably.

[0081] In the foregoing, preferred embodiments of the present invention have been described and illustrated using specific terms, but such terms are intended solely to clarify the present invention, and it is obvious that various modifications and changes may be made to the embodiments and described terms of the present invention without departing from the technical spirit and scope of the following claims. Such modified embodiments should not be understood separately from the spirit and scope of the present invention, but should be considered to fall within the scope of the claims of the present invention. Explanation of the symbols

[0083] 10: Arc current sensing unit 20: Voltage changing unit 30: Voltage amplifier 31: Operational amplifier 40: Comparator 50: Signal Transmitter 51: Photocoupler 60: Control unit 70: Output signal generation unit 71: MOSFET 80: Main switching section 91: CPU 92: Main System

Claims

Claim 1 The apparatus comprises: an arc current sensing unit that senses an arc generated in an X-ray tube and measures an arc current value; a voltage changing unit that converts the measured current value into a voltage using centripetal resistors (R1) and (R2); a voltage amplification unit that amplifies the voltage value changed by the voltage changing unit using a non-inverting amplifier; a comparison unit that compares the amplified voltage with a preset reference voltage using an analog method with a comparator or amplifier, and transmits an arc-detecting (ARCING_DET) signal indicating that an arc has occurred through a photocoupler if the voltage is greater than or equal to the reference voltage; a signal transmission unit that outputs a blocking signal by converting the input arc-detecting signal to low to block the output signal; and an output signal generation unit that blocks the final output by operating a signal blocking MOSFET connected between the main MOSFET gate signal and GND using the blocking signal as input, wherein the output signal generation unit blocks the final output by switching the main switching unit within a time of several microseconds (μs) or less through the blocking signal processed in real time by the analog method. Arc control device in an X-ray tube. Claim 2 In claim 1, the arc control device in the X-ray tube monitors the measured current value through the voltage changed in the voltage changing unit. Claim 3 delete Claim 4 delete Claim 5 In claim 1, the arc control device in the X-ray tube further comprises a control unit that generates a control signal using the blocking signal and outputs it to the output signal generating unit, thereby controlling the output of the main switching unit to be blocked first. Claim 6 In claim 5, the control unit controls the secondary blocking of the output signal to be performed simultaneously with the primary blocking using a control CPU and a main system, in an arc control device for an X-ray tube. Claim 7 The arc current sensing unit includes a current measurement step for sensing an arc generated in an X-ray tube and measuring an arc current value; the voltage changing unit includes a voltage amplification step for converting the measured current value into a voltage using centrifugal resistors (R1) and (R2) and then amplifying the converted voltage value using a non-inverting amplifier; the comparison unit includes a voltage abnormality detection step for comparing the amplified voltage with a preset reference voltage in an analog manner using a comparator or amplifier, and transmitting an arc-detecting (ARCING_DET) signal indicating that an arc has occurred through a photocoupler if the voltage is greater than or equal to the reference voltage; the signal transmission unit includes a blocking signal output step for converting the arc-detecting signal to low and outputting it as a blocking signal to block the output signal; and the output signal generation unit includes a main MOSFET control step for blocking the main switching unit by controlling the operation of a signal blocking MOSFET connected between the main MOSFET gate signal and GND using the blocking signal, wherein the main MOSFET control step receives the blocking signal processed in real time by the analog method An arc control method in an X-ray tube characterized by blocking the final output by operating the signal blocking MOSFET within a time of less than a microsecond (μs) to switch the main switching unit. Claim 8 A method for controlling an arc in an X-ray tube according to claim 7, wherein the current measurement step is characterized by detecting whether the current increases instantaneously during X-ray irradiation. Claim 9 In claim 7, the voltage amplification step comprises a step of monitoring a current value measured through the changing voltage, in an arc control method in an X-ray tube. Claim 10 delete Claim 11 In claim 7, the arc control method in the X-ray tube further comprises a first control step of generating a control signal using the blocking signal and outputting it to the output signal generating unit to control the output of the main switching unit to be first blocked. Claim 12 A method for controlling an arc in an X-ray tube according to claim 11, wherein the first control step comprises a second control step that controls the second blocking of an output signal to be performed using a control CPU and a main system simultaneously with the first blocking.

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