An integrated radiation source for dental CBCT

Abstract

The invention relates to the technical field of ray sources, and discloses an integrated ray source for dental CBCT, including an inverter board and a high-voltage box, wherein the inverter board is used to provide the high-frequency current required by the high-voltage box and drive the tube filament, and the high-voltage box is used to further boost the high-frequency alternating current and rectify it into a direct current to be added to the two poles of the tube for generating the required X-rays; the high-voltage box includes a high-voltage transformer, and the output end of the high-voltage transformer is connected to a voltage doubling circuit, and the voltage doubling circuit is used to multi-stage boost rectification to obtain a KV voltage supplied to the tube, and the KV voltage is fed back to the inverter board through a KV feedback circuit, and the inverter board is connected to an error amplifier adjustment circuit, and the error amplifier adjustment circuit is used to adjust the KV feedback signal to reduce voltage fluctuations and output as an input control signal for a subsequent PWM drive. The ray source has a compact structure, a small volume, a high output voltage, and a small KV ripple, and can meet the needs of most applications.

Description

Technical Field

[0001] The present invention relates to the technical field of radiation sources, and in particular to an integrated radiation source for dental CBCT. Background Art

[0002] Medical diagnostic high-frequency X-ray machines (including analog X-ray machines and digital X-ray machines) are used to examine all parts of the human body and are used by medical institutions for X-ray photography diagnosis. X-ray machines can be used in multiple departments, such as orthopedics, wards, emergency rooms, operating rooms, ICUs, etc.

[0003] As a powerful tool for oral examination and treatment, oral CBCT imaging equipment has developed rapidly, but at the same time, higher requirements have been placed on one of its core components, the high-voltage radiation source. The function of the radiation source is to produce high-quality x-rays for generating medical images. The maximum output voltage of conventional dental CBCT radiation sources is only 90kV, and they are usually complex in structure, with low output voltage and large ripple. Currently, they can no longer meet the needs of system manufacturers for complex image algorithms. Summary of the invention

[0004] In view of the deficiencies in the prior art, an object of the present invention is to provide an integrated CBCT radiation source with a more compact structure, higher power and better radiation quality.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] An integrated radiation source for dental CBCT, comprising an inverter board and a high-voltage box, wherein the inverter board is used to provide the high-frequency current required by the high-voltage box and drive the filament of the tube, and the high-voltage box is used to further boost the high-frequency alternating current and rectify it into direct current to be added to the two poles of the tube for generating the required X-rays;

[0007] The high-voltage box includes a high-voltage transformer, and the output end of the high-voltage transformer is connected to a voltage doubling circuit. The voltage doubling circuit is used for multi-stage boost rectification to obtain a KV voltage supplied to the bulb. The KV voltage is fed back to the inverter board through a KV feedback circuit. The inverter board is connected to an error amplifier adjustment circuit. The error amplifier adjustment circuit is used to adjust the KV feedback signal to reduce voltage fluctuations and output it as an input control signal for the subsequent PWM drive.

[0008] In the present invention, further, the voltage doubling circuit includes multi-stage voltage regulation, and KV+ and KV- voltages are obtained respectively through the multi-stage voltage regulation, wherein each stage of the voltage regulation part includes a high-voltage diode and a capacitor.

[0009] In the present invention, further, the KV feedback circuit includes a resistor R3, and the KV+ voltage is transmitted to the inverter board after being divided by the resistor R3.

[0010] In the present invention, further, the error op amp adjustment circuit includes an amplifier U31D, a follower U31B and an error amplifier U35A, the KV feedback signal is input to the in-phase end of the amplifier U31D, the output end of the amplifier U31D is connected to the inverting end of the follower U31B, and the output end of the follower U31B is connected to the inverting end of the error amplifier U35A.

[0011] In the present invention, further, the high-voltage box includes a voltage doubler plate, the high-voltage transformer is embedded in the middle of the voltage doubler plate, cathode plates and anode plates are respectively arranged on both sides of the voltage doubler plate, and the cathode plates and anode plates are respectively connected to the positive and negative poles of the bulb.

[0012] In the present invention, further, a filament transformer is embedded on the voltage multiplier plate, and the filament transformer is connected to the filament in the bulb through a cathode plate, and the bulb is located at the bottom of the high-voltage box.

[0013] In the present invention, further, a sealing plate is provided on the upper side of the voltage doubler plate, and a plurality of terminals are provided on the sealing plate to be connected with the inverter plate to realize signal transmission.

[0014] In the present invention, further, it also includes a power board, which is connected to the inverter board, and the power board is used to provide direct current required for the inverter board to work.

[0015] In the present invention, preferably, the voltage doubling circuit is provided with a connection terminal P1 and a connection terminal P2 of a high-voltage transformer, and the voltage doubling circuit includes a resistor R6, one end of the resistor R6 is connected to the connection terminal P1, and the other end is connected to the anode of the high-voltage diode D2, the cathode of the high-voltage diode D2 is connected to the capacitor C8 and the anode of the high-voltage diode D3, the cathode of the high-voltage diode D3 is connected to the capacitor C13 and the anode of the high-voltage diode D4, the cathode of the high-voltage diode D4 is connected to the capacitor C9 and the anode of the high-voltage diode D5, the cathode of the high-voltage diode D5 is connected to the capacitor C14 and the anode of the high-voltage diode D6, the cathode of the high-voltage diode D6 is connected to the capacitor C10 and the anode of the high-voltage diode D7, and the cathode of the high-voltage diode D7 obtains a KV+ voltage.

[0016] In the present invention, preferably, the connection end P2 is connected to a capacitor C24, the capacitor C24 is connected to the cathode of a high-voltage diode D13, the anode of the high-voltage diode D13 is connected to a capacitor C18 and a cathode of a high-voltage diode D14, the anode of the high-voltage diode D14 is connected to a capacitor C25 and a cathode of a high-voltage diode D15, the anode of the high-voltage diode D15 is connected to a capacitor C19 and a cathode of a high-voltage diode D6, the anode of the high-voltage diode D16 is connected to a capacitor C26 and a cathode of a high-voltage diode D17, and the anode of the high-voltage diode D17 obtains a KV- voltage.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] (1) The present invention realizes multi-stage voltage boosting through a voltage doubling circuit. Without increasing the volume, the maximum output voltage is increased to 120 kV, which meets the needs of most applications. At the same time, the present invention is provided with a KV feedback circuit, which feeds back the output signal of part of the voltage doubling circuit to the inverter board, thereby stabilizing the static operating point of the voltage doubling circuit and stabilizing the circuit, thereby achieving the effect of high output voltage and small KV ripple.

[0019] (2) In order to ensure the stability of the system and to have sufficient frequency response so that the system can obtain a smaller voltage fluctuation when the load changes, the present invention sets an error amplifier adjustment circuit, specifically using three types of error amplifier adjusters, which have two zeros and three poles, with the zeros in front and the poles in the back, which can enhance more phases, push up the shear frequency, and improve the system response speed. In addition, when the KV set value changes, this circuit can ensure a fast and stable response of the KV output to avoid oscillation or slow response.

[0020] (3) The interior of the high-voltage box of the present invention is rationally arranged around the voltage doubler board as a whole. By integrating most of the circuits onto a circuit board, the connections between the modules are reduced as much as possible. The high-voltage transformer is embedded in the middle of the voltage doubler board, which effectively reduces the thickness of the box. An integrated insulating sleeve is used for insulation between the primary and secondary of the filament transformer, which also greatly reduces the size of the transformer. In the above manner, the high-voltage box is made more compact. In addition, the main heat-generating component, the bulb, is arranged at the bottom of the box, which is conducive to the flow of insulating oil and makes the heat dissipation effect better. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0022] Figure 1 This is a diagram of the overall working principle of an integrated radiation source for dental CBCT of the present invention;

[0023] Figure 2 It is a schematic diagram of partial circuit connection of an integrated radiation source for dental CBCT of the present invention;

[0024] Figure 3 It is a schematic diagram of the internal connection of a high-voltage box of an integrated radiation source for dental CBCT of the present invention;

[0025] Figure 4 It is a circuit diagram of a voltage doubling circuit and a KV feedback circuit of an integrated radiation source for dental CBCT of the present invention;

[0026] Figure 5 It is a circuit diagram of an error amplifier adjustment circuit of an integrated radiation source for dental CBCT of the present invention;

[0027] In the figure: 1. Power supply board; 2. Inverter board; 3. High-voltage box; 4. Voltage doubler board; 5. Sealing board; 6. High-voltage transformer; 7. Filament transformer; 8. Cathode board; 9. Anode board; 10. Tube; 11. Voltage doubler circuit; 12. KV feedback circuit; 13. Error amplifier adjustment circuit. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] It should be noted that when a component is referred to as being "fixed to" another component, it may be directly on the other component or there may also be a component centered. When a component is considered to be "connected to" another component, it may be directly connected to the other component or there may also be a component centered. When a component is considered to be "set on" another component, it may be directly set on the other component or there may also be a component centered. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0031] Please also see Figure 1 to Figure 2 The present invention provides an integrated radiation source for dental CBCT in a preferred embodiment, including a power board 1, an inverter board 2 and a high-voltage box 3. The power board 1 is connected to the inverter board 2, and the inverter board 2 is connected to the high-voltage box 3. The power board 1 is used to provide the required direct current for the inverter board 2 to work, the inverter board 2 is used to provide the high-frequency current required by the high-voltage box 3 and drive the filament of the tube 10, and the high-voltage box 3 is used to further boost the high-frequency alternating current and rectify it into direct current to be added to the two poles of the tube 10 for generating the required X-rays.

[0032] Specifically, in this embodiment, the power board 1 has two functions: one is to provide the DC voltage required by the inverter board 2, including +24V, +15V and -15V, and the other is to provide the DC bus required by the integrated circuit on the inverter board 2.

[0033] The inverter board 2 is the control core of this system. The inverter board 2 integrates the main control module, IGBT module, filament drive module and communication module. The IGBT module and filament drive module are connected to the main control module. The IGBT module is used to chop the DC power of the power board 1 into high-frequency AC power. The main control module provides the main control function, including the setting of exposure parameters, the control of the exposure process and fault detection. The filament drive module is used to provide the filament drive function of the tube 10. The communication module of this solution uses 232 communication mode to facilitate the conversion of the interface and communication mode.

[0034] The high-voltage box 3 is one of the core components of the radiation source. Since it needs to be designed to balance weight and size with the radiation receiving device, i.e., the flat-panel detector, if it is too large, it will affect the appearance design of the whole machine and require additional weights, which increases the cost. The improvement focus of the present invention is also mainly on the improvement of the volume of the high-voltage box 3, the internal circuit and the parameters. The volume of the high-voltage box 3 of the radiation source is reduced by more than one third compared with the existing products on the market, but the insulation performance and heat dissipation rate are higher, which is conducive to reducing the risk of internal insulation failure, improving the KV voltage level, and achieving the purpose of longer use time under the same conditions of use.

[0035] The specific working principle is: the power board 1 inputs an AC 220V power supply, and after the rectification and filtering circuit of the power board 1, a stable DC voltage of about 310V is generated. The DC voltage is provided to the inverter board 2, and then the IGBT module on the inverter board 2 chops it into high-frequency AC power, where the amplitude of the AC power is determined by the set voltage KV value. It is a hardware closed-loop control system, which will be explained in the subsequent introduction.

[0036] The high-frequency alternating current generated by the inverter board 2 is provided to the high-voltage box 3, and after multi-stage voltage doubling and rectification by the high-voltage box 3, the required DC high voltage is finally generated. The high-voltage box 3 contains a tube 10, which is a component that generates x-rays. After the DC high voltage is applied to both ends, a high-voltage electric field is formed inside it. The filament inside the tube 10 is lit under the drive of the filament driving circuit on the inverter board 2, generating a large number of free electrons. Under the action of the high-voltage electric field, these electrons move at high speed and hit the anode target surface of the tube 10, generating x-rays.

[0037] In the present invention, further, as Figure 3As shown, the high-voltage box 3 includes a voltage multiplier plate 4, a sealing plate 5 is provided on the upper side of the voltage multiplier plate 4, and a plurality of terminals are provided on the sealing plate 5 to connect with the inverter plate 2 to realize signal transmission. The voltage transmitted by the inverter plate 2 is introduced through the sealing plate 5, which increases the sealing of the connection between the two. The high-voltage transformer 6 is embedded in the middle of the voltage multiplier plate 4, and a cathode plate 8 and an anode plate 9 are respectively provided on both sides of the voltage multiplier plate 4. The cathode plate 8 and the anode plate 9 are respectively connected to the cathode and cathode of the bulb 10. In addition, a filament transformer 7 is also embedded in the voltage multiplier plate 4, and the filament transformer 7 is connected to the filament in the bulb 10 through the cathode plate 8. The bulb 10 is located at the bottom of the high-voltage box 3.

[0038] In one embodiment provided by the present invention, for example, the high-frequency alternating current generated by the inverter board 2 enters the primary terminals E1 and E2 of the high-frequency high-voltage transformer 6 in the high-voltage box 3 through the terminal SJ1 on the sealing plate 5, and its secondary output terminals E8 and E9 are high-frequency alternating current after voltage boosting. The high-frequency alternating current boosted by the high-voltage transformer 6 enters the input of the voltage doubler circuit 11, and after voltage doubler rectification, its cathode enters the cathode plate 8 through the E6 terminal, and the current limiting resistor R1 on the cathode plate 8 starts the current limiting protection function. The other end of the current limiting resistor R1 is connected to the cathode of the bulb 10 through the E4 terminal, which is also one end of the filament. The anode output of the voltage doubler board 4 enters the anode plate 9 through the E7 terminal, and is also connected to the anode end of the bulb 10 through the current limiting resistor R1.

[0039] The filament driving signal generated by the filament driving circuit on the inverter board 2 enters the primary terminals E3, E4 and E5 of the filament transformer 7 through the SJ2 port on the sealing board 5, where E3 is the common terminal. The secondary output E1 of the filament transformer 7 is connected to the other end of the filament through the E3 terminal on the cathode board 8, and the secondary output E2 of the filament transformer 7 is connected to the E4 terminal, which has the same potential as the cathode KV.

[0040] The entire box is rationally laid out around the voltage doubler board 4. By integrating most of the circuits onto a circuit board (voltage doubler board 4), the connections between the modules are reduced as much as possible. The design of the cathode plate 8 and the anode plate 9 reduces the distribution of cables in the box. The high-voltage transformer 6 and the filament transformer 7 are embedded on the voltage doubler board 4, which effectively reduces the thickness of the box. The primary and secondary of the filament transformer 7 are insulated with an integrated insulating sleeve, which also greatly reduces the size of the transformer. In the above manner, the high-voltage box 3 is made more compact. In addition, the main heating component, the bulb 10, is arranged at the bottom of the box, which is conducive to the flow of insulating oil and makes the heat dissipation effect better.

[0041] The maximum output voltage of conventional dental CBCT radiation sources is only 90kV, and the KV ripple is greater than 2%, which currently cannot meet the needs of system manufacturers for complex image algorithms. This radiation source increases the maximum output voltage to 120kV without increasing the volume, meeting the needs of most applications.

[0042] Specifically, the output end of the high-voltage transformer 6 is connected to a voltage doubling circuit 11, which is used for multi-stage boost rectification to obtain a KV voltage supplied to the bulb 10. The KV voltage is fed back to the inverter board 2 through a KV feedback circuit 12. The inverter board 2 is connected to an error amplifier adjustment circuit 13, which is used to adjust the KV feedback signal to reduce voltage fluctuations and output it as an input control signal for the subsequent PWM drive.

[0043] The high-frequency alternating current generated by the inverter board 2 is provided to the high-voltage box 3, and is further boosted by the high-voltage transformer 6 inside the high-voltage box 3. The output of the high-voltage transformer 6 is connected to the voltage doubling circuit 11, and after multi-stage voltage doubling rectification, the required DC high voltage is finally generated. Among them, in the present invention, part of the voltage output by the voltage doubling circuit 11 is fed back to the inverter board 2 through the KV feedback circuit 12, and the KV feedback signal generated by the inverter board 2 is adjusted by the error amplifier adjustment circuit 13 to reduce the voltage fluctuation and output as the input control signal of the subsequent PWM drive, which is used to control the filament drive circuit on the inverter board 2, thus forming a hardware closed-loop control system. The present ray source reduces the ripple to less than 0.5% through the above-mentioned optimization design method, which is of great help in improving image clarity, reducing noise, and reducing the difficulty of image processing.

[0044] In the present invention, preferably, only a transformer is usually used for boosting, and the boosting multiple is limited. In order to output a higher voltage, the design adopts a multi-stage voltage doubler circuit 11, and the voltage doubler circuit 11 includes multi-stage voltage regulation, and the KV+ and KV- voltages are obtained through multi-stage voltage regulation, wherein each stage of voltage regulation includes a high-voltage diode and a capacitor. The KV feedback circuit 12 includes a resistor R3, and the KV+ piezoelectric is transmitted to the inverter board 2 after voltage division by the resistor R3, thus forming a KV negative feedback circuit to stabilize the static operating point of the voltage doubler circuit 11.

[0045] For example, Figure 4 As shown, the voltage doubling circuit 11 is provided with a connection terminal P1 and a connection terminal P2 of a high-voltage transformer 6, and the voltage doubling circuit 11 includes a resistor R6, one end of the resistor R6 is connected to the connection terminal P1, and the other end is connected to the anode of the high-voltage diode D2, the cathode of the high-voltage diode D2 is connected to the capacitor C8 and the anode of the high-voltage diode D3, the cathode of the high-voltage diode D3 is connected to the capacitor C13 and the anode of the high-voltage diode D4, the cathode of the high-voltage diode D4 is connected to the capacitor C9 and the anode of the high-voltage diode D5, the cathode of the high-voltage diode D5 is connected to the capacitor C14 and the anode of the high-voltage diode D6, the cathode of the high-voltage diode D6 is connected to the capacitor C10 and the anode of the high-voltage diode D7, and the cathode of the high-voltage diode D7 obtains a KV+ voltage.

[0046] The connection end P2 is connected to a capacitor C24, the capacitor C24 is connected to the cathode of the high-voltage diode D13, the anode of the high-voltage diode D13 is connected to the capacitor C18 and the cathode of the high-voltage diode D14, the anode of the high-voltage diode D14 is connected to the capacitor C25 and the cathode of the high-voltage diode D15, the anode of the high-voltage diode D15 is connected to the capacitor C19 and the cathode of the high-voltage diode D6, the anode of the high-voltage diode D16 is connected to the capacitor C26 and the cathode of the high-voltage diode D17, and the anode of the high-voltage diode D17 obtains a KV- voltage.

[0047] Specifically, P1 and P2 are two output terminals of the high-voltage transformer 6, where P1 is connected to the signal ground GND. When the voltage of P1 is higher than that of P2, C8 is charged through R6 and D2; when P1 and P2 are reversed, C18 is charged through D13; this is repeated many times, and finally a KV+ voltage is obtained at the cathode of D7 and a KV- voltage is obtained at the anode of D17. The KV+ voltage is divided by the voltage-dividing resistor R3 and fed back to the inverter board 2.

[0048] In the present invention, further, existing products can usually only have fixed parameter exposure and cannot achieve dynamic adjustment of KV. In order to ensure system stability and sufficient frequency response so that the system can obtain smaller voltage fluctuations when the load changes, this design adopts the error amplifier adjustment circuit 13 of the three types of error amplifier regulators to achieve the function of dynamically adjusting the exposure parameters and has a faster response speed.

[0049] Specifically, Figure 5As shown, the error operational amplifier adjustment circuit 13 includes an amplifier U31D, a follower U31B and an error amplifier U35A. The KV feedback signal KV_feedback is input to the in-phase end of the amplifier U31D through a resistor R111, a diode CR56 and a resistor R112. The inverting end of the amplifier U31D is connected to a resistor R116 and one end of a capacitor C108. The other ends of the resistor R116 and the capacitor C108 are connected to the output end of the amplifier U31D. The nodes of the resistor R116, the capacitor C108 and the inverting end of the amplifier U31D are connected in series with resistors R115, R114 and R113 to ground in sequence. The output end of the amplifier U31D is connected to the inverting end of the follower U31B through a resistor R30. The output end of the follower U31B is connected to the inverting end of the follower U31B through a resistor R102, resistor R124, and capacitor C14 are connected to the inverting end of the error amplifier U35A. The voltage KV set value KV_SET_OUT is input into the inverting end of the error amplifier U35A through the resistor R31. The KV set value determines the amplitude of the alternating current generated by the IGBT module on the inverter board 2. Resistor R102 is connected to one end of resistor R123. The other end of resistor R123 is connected to the inverting end of the error amplifier U35A and two nodes are set thereon. One node is connected to the output end of the error amplifier U35A through resistor R125 and capacitor C113, and the other node is connected to the output end of the error amplifier U35A through capacitor C112. Finally, the output end of the error amplifier U35A outputs KV_LOOP through resistor R127 as the input control signal of the subsequent PWM drive.

[0050] As mentioned above, this design uses three types of error amplifier regulators, which have two zeros and three poles, with zeros in front and poles in the back, which can improve more phases. Pushing up the shear frequency improves the system response speed. When the KV setting value changes, this design can ensure the fast and stable response of the KV output, avoid oscillation or slow response, and realize the dynamic adjustment of exposure parameters, and the exposure parameters have a sub-millisecond response speed.

[0051] In this embodiment, the working principle is:

[0052] The power board 1 inputs an AC 220V power supply, which generates a stable DC voltage of about 310V after being rectified and filtered by the power board 1. The DC voltage is provided to the inverter board 2, and then chopped into high-frequency AC power by the IGBT module on the inverter board 2. The amplitude of the AC power is determined by the set voltage KV value.

[0053] The high-frequency AC power generated by the inverter board 2 is provided to the high-voltage box 3. After further boosting by the high-voltage transformer 6 inside the high-voltage box 3, the output of the high-voltage transformer 6 is connected to the voltage doubler circuit 11, and after multi-stage voltage doubler rectification, the required DC high voltage is generated. On the one hand, the DC high voltage is fed back to the inverter board 2 through the KV feedback circuit 12, and the generated KV feedback signal is input to the error amplifier adjustment circuit 13 for adjustment and following to reduce voltage fluctuations, and finally input to the reverse end of the error amplifier U35A, while the voltage KV set value is input to the in-phase end of the error amplifier U35A, and finally output as the input control signal for the subsequent PWM drive to drive the filament drive circuit on the inverter board 2.

[0054] On the other hand, the generated DC high voltage is provided to the tube 10, forming a high-voltage electric field inside the tube 10. The filament in the tube 10 is driven by the filament driving circuit on the inverter board 2 to light up, generating a large number of free electrons. Under the action of the high-voltage electric field, these electrons move at high speed and hit the anode target surface of the tube 10, generating x-rays.

[0055] The above description is a detailed description of the preferred feasible embodiments of the present invention, but the embodiments are not intended to limit the scope of the patent application of the present invention. All equivalent changes or modified changes completed under the technical spirit suggested by the present invention should fall within the patent scope covered by the present invention.

Claims

1. An integrated radiation source for dental CBCT, It is characterized in that It includes an inverter board and a high-voltage box, wherein the inverter board is used to provide the high-frequency current required by the high-voltage box and drive the filament of the bulb tube, and the high-voltage box is used to further boost the high-frequency alternating current and rectify it into direct current to be added to the two poles of the bulb tube for generating the required X-rays; The high-voltage box includes a high-voltage transformer, the output end of the high-voltage transformer is connected to a voltage doubling circuit, the voltage doubling circuit is used for multi-stage boost rectification to obtain a KV voltage supplied to the bulb, the KV voltage is fed back to the inverter board through a KV feedback circuit, the inverter board is connected to an error amplifier adjustment circuit, the error amplifier adjustment circuit is used to adjust the KV feedback signal to reduce voltage fluctuations and output as an input control signal for a subsequent PWM drive; The error op amp adjustment circuit includes an amplifier U31D, a follower U31B and an error amplifier U35A. The KV feedback signal KV_feedback is input to the non-inverting end of the amplifier U31D. The output end of the amplifier U31D is connected to the inverting end of the follower U31B through a resistor R30. The output end of the follower U31B is connected to the inverting end of the error amplifier U35A. The voltage KV set value KV_SET_OUT is input to the non-inverting end of the error amplifier U35A through a resistor R31. The KV set value determines the amplitude of the alternating current generated by the IGBT module on the inverter board. The output end of the error amplifier U35A outputs KV_LOOP through a resistor R127 as the input control signal of the subsequent PWM drive.

2. The integrated radiation source for dental CBCT according to claim 1, It is characterized in that The voltage doubling circuit includes multiple stages of voltage regulation, through which KV+ and KV- voltages are obtained respectively, wherein each stage of voltage regulation includes a high-voltage diode and a capacitor.

3. The integrated radiation source for dental CBCT according to claim 2, It is characterized in that The KV feedback circuit includes a resistor R3, and the KV+ voltage is divided by the resistor R3 and then transmitted to the inverter board.

4. The integrated radiation source for dental CBCT according to claim 1, It is characterized in that The error operational amplifier adjustment circuit includes an amplifier U31D, a follower U31B and an error amplifier U35A. The KV feedback signal is input to the in-phase terminal of the amplifier U31D. The output terminal of the amplifier U31D is connected to the inverting terminal of the follower U31B. The output terminal of the follower U31B is connected to the inverting terminal of the error amplifier U35A.

5. The integrated radiation source for dental CBCT according to claim 1, It is characterized in that The high-voltage box comprises a voltage doubler plate, the high-voltage transformer is embedded in the middle of the voltage doubler plate, cathode plates and anode plates are respectively arranged on both sides of the voltage doubler plate, and the cathode plates and anode plates are respectively connected to the positive and negative poles of the bulb.

6. The integrated radiation source for dental CBCT according to claim 5, It is characterized in that The voltage multiplier plate is also embedded with a filament transformer, which is connected to the filament in the bulb through a cathode plate. The bulb is located at the bottom of the high-voltage box.

7. The integrated radiation source for dental CBCT according to claim 5, It is characterized in that A sealing plate is disposed on the upper side of the voltage multiplier plate, and a plurality of terminals are disposed on the sealing plate to be connected with the inverter plate to realize signal transmission.

8. The integrated radiation source for dental CBCT according to claim 1, It is characterized in that It also includes a power board, which is connected to the inverter board and is used to provide direct current required for the inverter board to work.

9. The integrated radiation source for dental CBCT according to claim 2, It is characterized in that The voltage doubling circuit is provided with a connection terminal P1 and a connection terminal P2 of a high-voltage transformer, and includes a resistor R6, one end of the resistor R6 is connected to the connection terminal P1, and the other end is connected to the anode of a high-voltage diode D2, the cathode of the high-voltage diode D2 is connected to a capacitor C8 and an anode of a high-voltage diode D3, the cathode of the high-voltage diode D3 is connected to a capacitor C13 and an anode of a high-voltage diode D4, the cathode of the high-voltage diode D4 is connected to a capacitor C9 and an anode of a high-voltage diode D5, the cathode of the high-voltage diode D5 is connected to a capacitor C14 and an anode of a high-voltage diode D6, the cathode of the high-voltage diode D6 is connected to a capacitor C10 and an anode of a high-voltage diode D7, and the cathode of the high-voltage diode D7 obtains a KV+ voltage.

10. The integrated radiation source for dental CBCT according to claim 9, It is characterized in that The connection end P2 is connected to a capacitor C24, the capacitor C24 is connected to the cathode of a high-voltage diode D13, the anode of the high-voltage diode D13 is connected to a capacitor C18 and the cathode of a high-voltage diode D14, the anode of the high-voltage diode D14 is connected to a capacitor C25 and the cathode of a high-voltage diode D15, the anode of the high-voltage diode D15 is connected to a capacitor C19 and the cathode of a high-voltage diode D6, the anode of the high-voltage diode D16 is connected to a capacitor C26 and the cathode of a high-voltage diode D17, and the anode of the high-voltage diode D17 obtains a KV- voltage.

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