Control system of adjustable bipolar secondary focusing voltage for X-ray source

Abstract

The invention discloses a control system of adjustable bipolar secondary focusing voltage for an X-ray source. The system comprises a setting module used for outputting a given voltage; the voltage output module is connected with a focusing sheet load of the X-ray source and is used for outputting a first positive voltage or a first negative voltage to the focusing sheet load of the X-ray source according to the magnitude of the given voltage; when the given voltage is greater than the preset voltage, the voltage output module outputs a first positive voltage; when the given voltage is smaller than or equal to the preset voltage, the voltage output module outputs first negative voltage; the voltage feedback module is used for generating sampling voltage according to the first positive voltage or the first negative voltage; and the control module is connected with the setting module and the voltage feedback module, is also connected with the voltage output module, and is used for generating an adjusting voltage according to the magnitude of the given voltage and the sampling voltage, and the voltage output module is used for adjusting the magnitude of the first positive voltage or the first negative voltage according to the adjusting voltage. The power supply and adjustment effects of the X-ray source are improved.

Description

Technical Field

[0001] This invention relates to the field of X-ray source technology, and in particular to a control system for an adjustable bipolar secondary focusing voltage for an X-ray source. Background Technology

[0002] In recent years, the electronics and new energy industries have developed rapidly, leading to an increasing demand for X-ray sources in both industrial and medical fields. Simultaneously, the requirements for penetration voltage and focal size have become increasingly stringent. Currently available X-ray sources are primarily single-stage focusing and positive voltage focusing modes. As customers demand higher penetration voltage and focal size, single-stage focusing and positive voltage focusing modes can no longer meet the high penetration and high resolution requirements of high-voltage micro-focus X-ray sources, resulting in excessively large focal sizes and poor resolution.

[0003] However, in the secondary focusing mode, when powering the focusing plate load of the X-ray source, the existing technology provides a poor power supply and regulation effect for the X-ray source. Summary of the Invention

[0004] This invention provides a control system for an adjustable bipolar secondary focusing voltage for an X-ray source, in order to solve the problem of poor power supply and adjustment effect of the X-ray source.

[0005] According to one aspect of the present invention, a control system for an adjustable bipolar secondary focusing voltage for an X-ray source is provided, comprising:

[0006] The setting module is used to output a given voltage;

[0007] A voltage output module, connected to the focusing plate load of the X-ray source, is used to output a first positive voltage or a first negative voltage to the focusing plate load of the X-ray source according to the magnitude of the given voltage; when the given voltage is greater than a preset voltage, the voltage output module outputs the first positive voltage; when the given voltage is less than or equal to the preset voltage, the voltage output module outputs the first negative voltage.

[0008] A voltage feedback module, connected to the voltage output module, is used to generate a sampling voltage based on the first positive voltage or the first negative voltage;

[0009] The control module is connected to the setting module and the voltage feedback module, and also to the voltage output module. It is used to generate an adjustment voltage based on the magnitude of the given voltage and the sampled voltage. The voltage output module is used to adjust the magnitude of the first positive voltage or the first negative voltage based on the adjustment voltage.

[0010] Optionally, the control module includes: a comparison unit and a control unit;

[0011] The first input terminal of the comparison unit is connected to the output terminal of the setting module, the second input terminal of the comparison unit is connected to the output terminal of the voltage feedback module, and the output terminal of the comparison unit is connected to the input terminal of the control unit. The comparison unit is used to generate a comparison voltage based on the magnitude of the given voltage and the sampled voltage.

[0012] The output terminal of the control unit is connected to the voltage output module, and the control unit is used to generate an adjustment voltage based on the comparison voltage.

[0013] Optionally, the comparison unit includes: a first comparator, a first resistor, a third resistor, a fourth resistor, a tenth resistor, a first capacitor, a fourth capacitor, a fifth capacitor, and a thirteenth capacitor;

[0014] The fourth resistor is connected between the output terminal of the setting module and the inverting input terminal of the first comparator; the fourth capacitor and the third resistor are connected in series between the first and second terminals of the fourth resistor; the fifth capacitor is connected between the inverting input terminal and the output terminal of the first comparator; the first capacitor and the first resistor are connected in series between the first and second terminals of the fifth capacitor.

[0015] The tenth resistor is connected between the positive input terminal of the first comparator and the output terminal of the voltage feedback module; the first terminal of the thirteenth capacitor is connected to the positive input terminal of the first comparator; and the second terminal of the thirteenth capacitor is grounded.

[0016] The first comparator generates a comparison voltage based on the magnitude of the given voltage and the sampled voltage.

[0017] Optionally, the control unit includes: a first transistor, a second transistor, a second resistor, a seventh resistor, an eleventh resistor, a second capacitor, a third capacitor, an eighth capacitor, an eleventh capacitor, and a twelfth capacitor;

[0018] The first end of the seventh resistor is connected to the output terminal of the first comparator, the second end of the seventh resistor is connected to the control terminal of the first transistor, the eleventh resistor and the eleventh capacitor are both connected between the control terminal and the ground terminal of the first transistor, the eighth capacitor is connected between the first end of the first transistor and the ground terminal, the second end of the first transistor is grounded, the first end of the first transistor is connected to the second end of the second resistor, the first end of the second resistor is connected to the first end of the second transistor, the control terminal of the second transistor is connected to the first end of the first transistor, the twelfth capacitor is connected between the second end of the second transistor and the ground terminal; the first end of the second transistor is also connected to the first power supply terminal, and the second capacitor and the third capacitor are both connected between the first power supply terminal and the ground terminal.

[0019] Optionally, the setting module includes: a second operational amplifier, a sixth resistor, a ninth resistor, and a tenth capacitor;

[0020] The inverting input of the second operational amplifier is connected to its output. The output of the second operational amplifier is also connected to the first input of the control module. The non-inverting input of the second operational amplifier is connected to the second terminal of the sixth resistor. The first terminal of the sixth resistor is connected to the first terminal of the ninth resistor. The second terminal of the ninth resistor is connected to ground. The second terminal of the sixth resistor is connected to the first terminal of the tenth capacitor. The second terminal of the tenth capacitor is connected to ground. The first terminal of the sixth resistor is used to receive a set voltage. The second operational amplifier is used to generate the given voltage based on the set voltage. The set voltage and the given voltage are equal in magnitude.

[0021] When the given voltage is greater than the preset voltage, the voltage output module is used to adjust and output the first positive voltage according to the adjusted voltage;

[0022] When the given voltage is less than or equal to the preset voltage, the voltage output module is used to adjust and output the first negative voltage according to the adjustment voltage.

[0023] Optionally, the voltage output module includes: a pulse width modulation unit and a boost unit, the pulse width modulation unit is connected to the second power supply terminal, and the pulse width modulation unit is used to alternately output a first modulation voltage and a second modulation voltage, wherein the voltage waveforms of the first modulation voltage and the second modulation voltage are symmetrical;

[0024] The boost unit is connected to the pulse width modulation unit and is used to receive the first modulation voltage and the second modulation voltage, and output a first positive voltage or a first negative voltage.

[0025] Optionally, the pulse width modulation unit includes:

[0026] Pulse width modulation chip, fifth resistor, eighth resistor, twelfth resistor, thirteenth resistor, seventeenth resistor, eighteenth resistor, nineteenth resistor, twenty-fourth resistor, twenty-fifth resistor, twenty-sixth resistor, thirtieth resistor, thirty-first resistor, thirty-second resistor, thirty-fourth resistor, sixth capacitor, ninth capacitor, fourteenth capacitor, sixteenth capacitor, eighteenth capacitor, twentieth capacitor, twenty-third capacitor, twenty-sixth capacitor, twenty-ninth capacitor, thirty-first capacitor, first switching transistor and second switching transistor;

[0027] The first, second, and twelfth pins of the pulse width modulation chip are connected to the ground terminal, the fifth and seventh pins of the pulse width modulation chip are connected to the ground terminal through the eighteenth capacitor, and the sixth pin of the pulse width modulation chip is connected to the ground terminal through the eighteenth resistor.

[0028] The 26th resistor, the 32nd resistor, and the 34th resistor are connected in series between the 16th pin of the pulse width modulation chip and the ground terminal. The 15th pin of the pulse width modulation chip is connected to the second power supply terminal. The 9th capacitor is connected between the second power supply terminal and the ground terminal. The 6th capacitor is connected between the 16th pin of the pulse width modulation chip and the second terminal of the 9th capacitor.

[0029] The fourteenth pin of the pulse width modulation chip is connected to the control terminal of the first switching transistor through the eighth resistor. The twelfth resistor is connected between the control terminal and the second terminal of the first switching transistor. The first terminal of the first switching transistor is connected to the first input terminal of the boost unit. The fifth resistor and the fourteenth capacitor are connected in series between the first terminal of the first switching transistor and the ground terminal.

[0030] The thirteenth pin of the pulse width modulation chip is connected to the thirteenth resistor, the sixteenth capacitor, and the twentieth capacitor. The second end of the thirteenth resistor is connected to the second power supply terminal, and the second ends of the sixteenth capacitor and the twentieth capacitor are connected to the ground terminal.

[0031] The eleventh pin of the pulse width modulation chip is connected to the control terminal of the second switching transistor through the nineteenth resistor. The twenty-fourth resistor is connected between the control terminal and the second terminal of the second switching transistor. The second terminal of the twenty-fourth resistor is also connected to the second terminal of the twelfth resistor. The first terminal of the second switching transistor is connected to the second input terminal of the boost unit. The seventeenth resistor and the twenty-third capacitor are connected in series between the first terminal of the second switching transistor and the ground terminal.

[0032] The tenth pin of the pulse width modulation chip is connected to the first end of the twenty-ninth capacitor, the thirty-first capacitor, the thirty-first resistor, and the thirty-second resistor, and the second end of the twenty-ninth capacitor, the thirty-first capacitor, and the thirty-second resistor is connected to the ground terminal.

[0033] The ninth pin of the pulse width modulation chip is connected to the ground terminal through the thirty-first resistor, and is also connected to the first terminal of the twenty-sixth resistor through the twenty-fifth resistor.

[0034] Optionally, the boost unit includes: a transformer, a seventh capacitor, a fifteenth capacitor, a thirty-fifth capacitor, a second diode, and a third diode;

[0035] The first input terminal of the transformer is connected to the first terminal of the first switching transistor, the second input terminal of the transformer is connected to the first terminal of the second switching transistor, and the third input terminal of the transformer is connected to the output terminal of the control module.

[0036] The first output terminal of the transformer is connected to the first terminal of the seventh capacitor, the second terminal of the seventh capacitor is connected to the first terminal of the second diode, and also to the second terminal of the third diode. The fifteenth capacitor is connected between the second terminal of the second diode and the first terminal of the third diode. The second output terminal of the transformer is connected to the first terminal of the fifteenth capacitor. The thirty-fifth capacitor is connected between the second terminal of the fifteenth capacitor and the ground terminal. The thirty-fifth capacitor is also connected in parallel with the fourth power supply.

[0037] The second output terminal of the transformer is used to output the first positive voltage or the first negative voltage.

[0038] Optionally, the voltage feedback module includes: a voltage conversion unit, a voltage inversion unit, and a voltage follower unit;

[0039] The input terminal of the voltage conversion unit is connected to the output terminal of the voltage output module, and the voltage conversion unit is used to generate a conversion voltage based on the first positive voltage or the first negative voltage.

[0040] The input terminal of the voltage inversion unit is connected to the output terminal of the voltage conversion unit, and is used to convert the converted voltage into an inverted voltage, wherein the inverted voltage and the converted voltage are opposites of each other;

[0041] The input terminal of the voltage follower unit is connected to the output terminal of the voltage inversion unit, and the output terminal of the voltage follower unit is connected to the second input terminal of the control module, for generating the sampling voltage based on the inverted voltage, wherein the inverted voltage is the same magnitude as the sampling voltage.

[0042] Optionally, the voltage conversion unit includes: a 25th capacitor, a 27th capacitor, a 20th resistor, a 29th resistor, a 33rd resistor, and a third operational amplifier;

[0043] The 25th capacitor is connected between the output terminal of the voltage output module and the input terminal of the voltage inverting unit; the 20th resistor is connected in parallel with the 25th capacitor; and the 27th capacitor is connected between the second terminal of the 25th capacitor and the ground terminal.

[0044] The 29th resistor and the 33rd resistor are connected in series between the second terminal of the 25th capacitor and the ground terminal;

[0045] The voltage reversing unit includes: a 21st resistor, a 22nd resistor, a 27th resistor, a 19th capacitor, a 22nd capacitor, a 28th capacitor, a 32nd capacitor, and a 33rd capacitor;

[0046] The first end of the 27th resistor is connected to the second end of the 25th capacitor, the second end of the 27th resistor is connected to the inverting input of the third operational amplifier, the 22nd resistor is connected between the non-inverting input of the third operational amplifier and the ground terminal, the first power supply terminal of the third operational amplifier is connected to the second power supply terminal, the 19th capacitor and the 22nd capacitor are connected in parallel between the second power supply terminal and the ground terminal; the second power supply terminal of the third operational amplifier is connected to the third power supply terminal, and the 32nd capacitor and the 33rd capacitor are connected in parallel between the third power supply terminal and the ground terminal;

[0047] The voltage follower unit includes: a fourteenth resistor, a twenty-third resistor, a twenty-eighth resistor, and a fourth operational amplifier;

[0048] The fourteenth resistor is connected between the inverting input and output of the fourth operational amplifier, the twenty-third resistor is connected between the output of the third operational amplifier and the non-inverting input of the fourth operational amplifier, and the twenty-eighth resistor is connected between the fifth power supply terminal and the non-inverting input of the fourth operational amplifier.

[0049] The technical solution provided in this invention, by setting a control module, can adjust the output voltage of the voltage output module according to the relationship between the given voltage of the setting module and the sampled voltage of the voltage feedback module, so that the output voltage of the voltage output module has the characteristics of low ripple, high precision, controllability, and stability. Furthermore, by setting different preset voltages, the voltage output module can output both a first positive voltage and a first negative voltage, realizing the output of different positive and negative voltages. Therefore, this invention achieves the adjustment of the secondary focusing voltage of the focusing plate load of the X-ray source, and also achieves positive and negative voltage control, exhibiting good control performance.

[0050] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0051] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0052] Figure 1 This is a schematic diagram of a control system for an adjustable bipolar secondary focusing voltage for an X-ray source, provided by an embodiment of the present invention.

[0053] Figure 2 This is a schematic diagram of another control system for an adjustable bipolar secondary focusing voltage for an X-ray source provided by an embodiment of the present invention;

[0054] Figure 3 This is a schematic diagram of the structure of another control system for an adjustable bipolar secondary focusing voltage for an X-ray source provided by an embodiment of the present invention;

[0055] Figure 4 This is a schematic diagram of the structure of another control system for an adjustable bipolar two-stage focusing voltage for an X-ray source provided by an embodiment of the present invention. Detailed Implementation

[0056] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0057] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0058] This invention provides a control system for an adjustable bipolar secondary focusing voltage for an X-ray source. Figure 1 This is a schematic diagram of a control system for an adjustable bipolar two-stage focusing voltage for an X-ray source, provided as an embodiment of the present invention. (Reference) Figure 1 The system includes: a setting module 1, a voltage output module 2, a voltage feedback module 3, and a control module 4. The setting module 1 outputs a given voltage. The voltage output module 2 is connected to the focusing plate load 5 of the X-ray source and outputs a first positive voltage or a first negative voltage to the focusing plate load 5 of the X-ray source according to the magnitude of the given voltage; when the given voltage is greater than a preset voltage, the voltage output module 2 outputs the first positive voltage; when the given voltage is less than or equal to the preset voltage, the voltage output module 2 outputs the first negative voltage. The voltage feedback module 3 is connected to the voltage output module 2 and generates a sampling voltage based on the first positive voltage or the first negative voltage. The control module 4 is connected to the setting module 1 and the voltage feedback module 3, and also to the voltage output module 2. It generates an adjustment voltage based on the magnitude of the given voltage and the sampling voltage. The voltage output module 2 adjusts the magnitude of the first positive voltage or the first negative voltage based on the adjustment voltage.

[0059] In a multi-stage focusing system, after the first-stage focusing completes the initial convergence of the electron beam, the second-stage focusing serves as a subsequent fine-tuning stage. By applying a second-stage focusing voltage, the shape, size, and focusing accuracy of the electron beam are further controlled. Its core principle is to utilize the electric field generated by the voltage to perform secondary confinement of the electron beam, achieving higher focusing performance and facilitating features such as a smaller spot size and a more concentrated energy distribution. Therefore, outputting a precise second-stage focusing voltage to the focusing plate load 5 of the X-ray source is crucial.

[0060] Specifically, the setting module 1 can output a given voltage to the control module 4. Simultaneously, the voltage feedback module 3 generates a sampling voltage based on the first positive or first negative voltage output by the voltage output module 2. The control module generates an adjustment voltage based on the error between the given voltage and the sampling voltage. When the sampling voltage is higher than the given voltage, the voltage output module 2 controls the first positive or first negative voltage to decrease according to the magnitude of the adjustment voltage. When the sampling voltage is lower than the given voltage, the voltage output module 2 controls the first positive or first negative voltage to increase according to the magnitude of the adjustment voltage. Therefore, the voltage output module 2 adjusts the first positive or first negative voltage according to the magnitude of the adjustment voltage, keeping the output voltage of the voltage output module 2 stable and accurate. The first positive and first negative voltages constitute the secondary focusing voltage.

[0061] Since the regulated voltage is related to the given voltage output by the setting module 1, and the output voltage of the voltage output module 2 is related to the regulated voltage, the given voltage is also used to control the voltage output module 2 to output a first positive voltage or a first negative voltage.

[0062] When the given voltage is less than or equal to the preset voltage, the sampling voltage is adjusted to be equal to the given voltage, and the sampling voltage is also less than or equal to the preset voltage. At this time, the sampling voltage of the voltage feedback module 3 can only be less than or equal to the preset voltage when the voltage output module 2 outputs the first negative voltage.

[0063] When the given voltage is greater than the preset voltage, adjusting the sampling voltage to be equal to the given voltage will also result in a sampling voltage greater than the preset voltage. In this case, the sampling voltage of the voltage feedback module 3 can only be greater than the preset voltage if the voltage output module 2 outputs a first positive voltage. Therefore, by setting different given voltage values, the positive and negative voltages output by the voltage output module 2 can be adjusted.

[0064] The technical solution provided in this invention, by setting a control module, can adjust the output voltage of the voltage output module according to the relationship between the given voltage of the setting module and the sampled voltage of the voltage feedback module, so that the output voltage of the voltage output module has the characteristics of low ripple, high precision, controllability, and stability. Furthermore, by setting different preset voltages, the voltage output module can output both a first positive voltage and a first negative voltage, realizing the output of different positive and negative voltages. Therefore, this invention achieves the adjustment of the secondary focusing voltage of the focusing plate load of the X-ray source, and also achieves positive and negative voltage control, exhibiting good control performance.

[0065] Figure 2 This is a schematic diagram of another control system for an adjustable bipolar two-stage focusing voltage for an X-ray source, provided as an embodiment of the present invention. (Refer to...) Figure 2 Based on the above embodiments, optionally, the control module includes a comparison unit 41 and a control unit 42. The first input terminal of the comparison unit 41 is connected to the output terminal of the setting module 1, the second input terminal of the comparison unit 41 is connected to the output terminal of the voltage feedback module 3, and the output terminal of the comparison unit 41 is connected to the input terminal of the control unit 42. The comparison unit 41 is used to generate a comparison voltage based on the magnitude of the given voltage and the sampled voltage. The output terminal of the control unit 42 is connected to the voltage output module 2, and the control unit 42 is used to generate an adjustment voltage based on the comparison voltage.

[0066] The comparison unit 41 receives the given voltage output by the setting module 1 and the sampled voltage output by the voltage feedback module 3, and generates a comparison voltage based on the relationship between the given voltage and the sampled voltage. When the control unit 42 receives the comparison voltage, it generates an adjustment voltage based on the comparison voltage. The adjustment voltage is used to control the voltage output module 2 to adjust its output voltage.

[0067] Specifically, when the sampled voltage is less than the given voltage, the comparison unit 41 generates a comparison voltage, and the control unit 42 generates an adjustment voltage based on the comparison voltage. The voltage output module 2 controls the first positive voltage or the first negative voltage to decrease.

[0068] When the sampled voltage is greater than the given voltage, the comparison unit 41 generates a comparison voltage, and the control unit 42 generates an adjustment voltage based on the comparison voltage. The voltage output module 2 controls the first positive voltage or the first negative voltage to increase.

[0069] Therefore, by setting up a comparison unit and a control unit, the generation of the regulated voltage is realized, so that the voltage output module 2 can adjust the output voltage according to the regulated voltage, thereby enabling the voltage output module 2 to output a more accurate first positive voltage or first negative voltage.

[0070] Figure 3 This is a schematic diagram of a control system for an adjustable bipolar two-stage focusing voltage for an X-ray source, provided as an embodiment of the present invention. (Reference) Figure 3 Based on the above embodiments, optionally, the comparison unit includes 41: a first comparator U1, a first resistor R1, a third resistor R3, a fourth resistor R4, a tenth resistor R10, a first capacitor C1, a fourth capacitor C4, a fifth capacitor C5, and a thirteenth capacitor C13. The fourth resistor R4 is connected between the output terminal of the setting module 1 and the inverting input terminal of the first comparator U1. The fourth capacitor C4 and the third resistor R3 are connected in series between the first and second terminals of the fourth resistor R4. The fifth capacitor C5 is connected between the inverting input terminal and the output terminal of the first comparator U1. The first capacitor C1 and the first resistor R1 are connected in series between the first and second terminals of the fifth capacitor C5. The tenth resistor R10 is connected between the positive input terminal of the first comparator U1 and the output terminal of the voltage feedback module 3. The first terminal of the thirteenth capacitor C13 is connected to the positive input terminal of the first comparator U1, and the second terminal of the thirteenth capacitor C13 is grounded. The first comparator U1 generates a comparison voltage based on the magnitude of the given voltage and the sampled voltage.

[0071] The sampled voltage output by voltage feedback module 3 is transmitted to the positive input terminal of the first comparator U1 through a filter circuit composed of the tenth resistor R10 and the thirteenth capacitor C13. A PID control circuit, composed of the first resistor R1, the third resistor R3, the fourth resistor R4, the first capacitor C1, the fourth capacitor C4, the fifth capacitor C5, and the first comparator U1, controls the input voltage. The set voltage output by setting module 1 and the filtered sampled voltage pass through this PID control circuit, and a comparison voltage is output through the output terminal of the first comparator U1.

[0072] Continue to refer to Figure 3Based on the above embodiments, optionally, the control unit 42 includes: a first transistor T1, a second transistor T2, a second resistor R2, a seventh resistor R7, an eleventh resistor R11, a second capacitor C2, a third capacitor C3, an eighth capacitor C8, an eleventh capacitor C11, and a twelfth capacitor C12. The first terminal of the seventh resistor R7 is connected to the output terminal of the first comparator U1, and the second terminal of the seventh resistor R7 is connected to the control terminal of the first transistor T1. The eleventh resistor R11 and the eleventh capacitor C11 are both connected between the control terminal and ground of the first transistor T1. The eighth capacitor C8 is connected between the first terminal and ground of the first transistor T1. The second terminal of the first transistor T1 is grounded. The first terminal of the first transistor T1 is connected to the second terminal of the second resistor R2, and the first terminal of the second resistor R2 is connected to the first terminal of the second transistor T2. The control terminal of the second transistor T2 is connected to the first terminal of the first transistor T1. The twelfth capacitor C12 is connected between the second terminal and ground of the second transistor. The first terminal of the second transistor T2 is also connected to the first power supply terminal, and the second capacitor C2 and the third capacitor C3 are both connected between the first power supply terminal and ground. For example, the first power supply terminal can be used to provide a 24V voltage.

[0073] When the given voltage represented by the comparison voltage is greater than the sampling voltage, the seventh resistor R7 and the eleventh resistor R11 can be used to divide the comparison voltage, and the divided comparison voltage is filtered by the eleventh capacitor C11. At this time, the voltage and current at the control terminal of the first transistor T1 decrease, so the current at the first terminal of the first transistor T1 decreases, and the voltage drop of the second resistor R2 also decreases. Simultaneously, the 24V DC voltage at the first power supply terminal is connected to the first terminal of the second transistor T2 through the second capacitor C2, the third capacitor C3, and the second terminal of the second transistor T2. Because the voltage drop of the second resistor R2 decreases, the voltage and current at the control terminal of the second transistor T2 increase, and the voltage at the second terminal of the second transistor T2 increases. The voltage at the second terminal of the second transistor T2 is the adjustment voltage generated by the control unit 42. The voltage output module 2 can increase the output of the first positive voltage or the first negative voltage according to the increased adjustment voltage.

[0074] When the given voltage represented by the comparison voltage is less than the sampling voltage, the voltage and current at the control terminal of the first transistor T1 increase, thus increasing the current at the first terminal of the first transistor T1. Simultaneously, the voltage drop across the second resistor R2 increases. Because the voltage drop across the second resistor R2 increases, the voltage and current at the control terminal of the second transistor T2 decrease, and the voltage at the second terminal of the second transistor T2 decreases. The voltage output module 2 can then reduce the output of either the first positive voltage or the first negative voltage based on the reduced adjustment voltage.

[0075] Continue to refer to Figure 3Based on the above embodiments, optionally, the setting module 1 includes: a second operational amplifier U2, a sixth resistor R6, a ninth resistor R9, and a tenth capacitor C10. The inverting input terminal of the second operational amplifier U2 is connected to the output terminal of the second operational amplifier U2, and the output terminal of the second operational amplifier U2 is also connected to the first input terminal of the control module 4. The non-inverting input terminal of the second operational amplifier U2 is connected to the second end of the sixth resistor R6. The first end of the sixth resistor R6 is connected to the first end of the ninth resistor R9, and the second end of the ninth resistor R9 is connected to the ground terminal. The second end of the sixth resistor R6 is connected to the first end of the tenth capacitor C10, and the second end of the tenth capacitor C10 is connected to the ground terminal. The first end of the sixth resistor R6 is used to receive the setting voltage, and the second operational amplifier U2 is used to generate a given voltage according to the setting voltage; the setting voltage and the given voltage are equal in magnitude.

[0076] The set voltage is filtered by RC filters through resistor R9 (ninth resistor), resistor R6 (sixth resistor), and capacitor C10 (tenth capacitor) before entering the output of the second operational amplifier U2. Therefore, the given voltage output by the second operational amplifier U2 is the same as the set voltage. The set voltage can be adjusted by adjusting the magnitude of the given voltage.

[0077] Figure 4 This is a schematic diagram of a control system for an adjustable bipolar two-stage focusing voltage for an X-ray source, provided as an embodiment of the present invention. (Reference) Figure 4 Based on the above embodiments, optionally, the voltage output module 2 includes a pulse width modulation unit 21 and a boost unit 22. The pulse width modulation unit 21 is connected to a second power supply terminal and is used to alternately output a first modulation voltage and a second modulation voltage, the voltage waveforms of which are symmetrical. The boost unit 22 is connected to the pulse width modulation unit 21 and is used to receive the first modulation voltage and the second modulation voltage, and output a first positive voltage or a first negative voltage. Exemplarily, the second power supply terminal can be used to provide a 12V voltage.

[0078] Optionally, the pulse width modulation unit 21 includes: a pulse width modulation chip 211, a fifth resistor R5, an eighth resistor R8, a twelfth resistor R12, a thirteenth resistor R13, a seventeenth resistor R17, an eighteenth resistor R18, a nineteenth resistor R19, a twenty-fourth resistor R24, a twenty-fifth resistor R25, a twenty-sixth resistor R26, a thirtieth resistor R30, a thirty-first resistor R31, a thirty-second resistor R32, a thirty-fourth resistor R34, a sixth capacitor C6, a ninth capacitor C9, a fourteenth capacitor C14, a sixteenth capacitor C16, an eighteenth capacitor C18, a twentieth capacitor C20, a twenty-third capacitor C23, a twenty-sixth capacitor C26, a twenty-ninth capacitor C29, a thirty-first capacitor C31, a first switch Q1, and a second switch Q2. The first pin D1, the second pin D2, and the twelfth pin D12 of the pulse width modulation chip 211 are connected to the ground terminal. The fifth pin D5 and the seventh pin D7 of the pulse width modulation chip 211 are connected to the ground terminal through the eighteenth capacitor C18. The sixth pin D6 of the pulse width modulation chip 211 is connected to the ground terminal through the eighteenth resistor R8. The twenty-sixth resistor R26, the thirty-second resistor R32, and the thirty-fourth resistor R34 are connected in series between the sixteenth pin D16 of the pulse width modulation chip 211 and the ground terminal. The fifteenth pin D15 of the pulse width modulation chip 211 is connected to the second power supply terminal. The ninth capacitor C9 is connected between the second power supply terminal and the ground terminal. The sixth capacitor C6 is connected between the sixteenth pin D16 of the pulse width modulation chip 211 and the second terminal of the ninth capacitor C9.

[0079] Pin 14 of the pulse width modulation chip 211, D14, is connected to the control terminal of the first switching transistor Q1 via resistor R8. Resistor R12 is connected between the control terminal and the second terminal of the first switching transistor Q1. The first terminal of the first switching transistor Q1 is connected to the first input terminal of the boost unit 22. Resistor R5 and capacitor C14 are connected in series between the first terminal of the first switching transistor Q1 and the ground terminal. Pin 13 of the pulse width modulation chip 211, D13, is connected to resistor R13, capacitor C16, and capacitor C20. The second terminal of resistor R13 is connected to the second power supply terminal, and the second terminals of capacitor C16 and capacitor C20 are connected to the ground terminal. Pin 11 of the pulse width modulation chip 211 is connected to the control terminal of the second switch Q2 through resistor R19. Resistor R24 ​​is connected between the control terminal and the second terminal of the second switch Q2. The second terminal of resistor R24 ​​is also connected to the second terminal of resistor R12. The first terminal of the second switch Q2 is connected to the second input terminal of the boost unit 22. Resistor R17 and capacitor C23 are connected in series between the first terminal of the second switch Q2 and ground. Pin 10 of the pulse width modulation chip 211 is connected to the first terminal of capacitor C29, capacitor C31, resistor R30, and resistor R32. The second terminal of capacitor C29, capacitor C31, and resistor R30 is connected to ground. Pin 9 of the pulse width modulation chip 211 is connected to ground through resistor R31 and is also connected to the first terminal of resistor R6 through resistor R25.

[0080] The eighteenth resistor R18 and the eighteenth capacitor C18 are used to adjust the voltage frequency output by pins eleven (D11) and fourteenth (D14) of the pulse width modulation chip 211. When the eighteenth resistor R18 and the eighteenth capacitor C18 are fixed, the voltage frequency output by pins eleven (D11) and fourteenth (D14) is fixed. The twenty-fifth resistor R25 and the thirty-first resistor R31 form a voltage divider with the output voltages of pins eleven (D11) and nine (D9) of the pulse width modulation chip 211. For example, pin eleven (D11) of the pulse width modulation chip 211 can be fixed to output a voltage of 5.1V, so the output voltage of pin nine (D9) of the pulse width modulation chip 211 is also fixed.

[0081] Meanwhile, the 26th resistor R26, the 32nd resistor R32, and the 34th resistor R34 connected to the 16th pin D16 of the pulse width modulation chip 211, along with the 30th resistor R30, the 29th capacitor C29, and the 31st capacitor C31 connected to the 10th pin D10 of the pulse width modulation chip 211, together constitute a protection circuit for the pulse width modulation chip 211. For example, when the pin voltage of the pulse width modulation chip 211 exceeds the safe voltage, the pulse width modulation chip 211 stops operating; the safe voltage can be 1V.

[0082] Specifically, the thirty-fourth resistor R34 is the sampling resistor at the input of the boost unit 22. When the circuit is running normally, the voltage of the thirty-fourth resistor R34 is relatively small. When the circuit malfunctions, the current increases, causing the voltage of the thirty-fourth resistor R34 to increase. At this time, the voltage of the tenth pin D10 of the pulse width modulation chip 211 also increases. When this voltage is greater than 1V, the pulse width modulation chip 211 stops working, thereby ensuring the stable operation of the entire circuit.

[0083] Pin 11 of the pulse width modulation chip 211 outputs a first modulation voltage through resistor R8 and the first switch Q1. Pin 14 outputs a second modulation voltage through resistor R19 and the second switch Q2. By controlling the alternating conduction of the first and second switches Q1 and Q2, and in conjunction with pull-down resistors R12 and R24, the waveforms of the first and second modulation voltages are highly symmetrical. Resistor R5 and resistor C14 adjust the voltage waveform of the first modulation voltage, thereby eliminating noise. Resistor R17 and resistor C23 adjust the voltage waveform of the second modulation voltage, thereby eliminating noise.

[0084] Therefore, the pulse width modulation unit provided in this embodiment of the invention has a relatively safe and stable voltage output effect.

[0085] Continue to refer to Figure 4Based on the above embodiments, optionally, the boost unit 22 includes: a transformer TB1, a seventh capacitor C7, a fifteenth capacitor C15, a thirty-fifth capacitor C35, a second diode CR2, and a third diode CR3. The first input terminal of transformer TB1 is connected to the first terminal of the first switching transistor Q1; the second input terminal of transformer TB1 is connected to the first terminal of the second switching transistor Q2; and the third input terminal of transformer TB1 is connected to the output terminal of the control module 4. The first output terminal of transformer TB1 is connected to the first terminal of the seventh capacitor C7; the second terminal of the seventh capacitor C7 is connected to the first terminal of the second diode CR2 and also to the second terminal of the third diode CR3; the fifteenth capacitor C15 is connected between the second terminal of the second diode CR2 and the first terminal of the third diode CR3; and the second output terminal of transformer TB1 is connected to the first terminal of the fifteenth capacitor C15. The thirty-fifth capacitor C35 is connected between the second terminal of the fifteenth capacitor C15 and the ground terminal, and is also connected in parallel with the fourth power supply DY4. The second output terminal of transformer T2 is used to output a first positive voltage or a first negative voltage.

[0086] Transformer TB1 receives the first and second modulation voltages, and then outputs voltage through the first and second output terminals. When the first output terminal outputs electrical energy, the seventh capacitor C7 stores energy; when the second output terminal outputs electrical energy, the fifteenth capacitor C15 stores energy. The fourth power supply DY4 can be a 400V DC power supply, used to stabilize the potential at the second terminal of the fifteenth capacitor C15. The voltage at the second output terminal of transformer TB1 is either the first positive voltage or the first negative voltage. The energy stored in the fifteenth capacitor C15 can be used to adjust the first positive voltage or the first negative voltage. The fifteenth resistor R15 and the sixteenth resistor R16 can serve as dummy loads for the output voltage, replacing the focusing plate load of the X-ray source.

[0087] Because the fourth power supply DY4 can regulate the second terminal of the fifteenth capacitor C15 to a lower voltage of -400V, by providing different voltages to the first terminal of the fifteenth capacitor C15, the fifteenth capacitor C15 can store higher voltages, thereby achieving higher or lower voltage outputs. For example, the first positive voltage can be in the range of 0V-300V, and the first negative voltage can be in the range of -300V-0V.

[0088] Continue to refer to Figure 4Based on the above embodiments, optionally, the voltage feedback module includes: a voltage conversion unit 31, a voltage inversion unit 32, and a voltage follower unit 33. The input terminal of the voltage conversion unit 31 is connected to the output terminal of the voltage output module 2, and the voltage conversion unit 31 is used to generate a converted voltage based on a first positive voltage or a first negative voltage. The input terminal of the voltage inversion unit 32 is connected to the output terminal of the voltage conversion unit 31, and it is used to convert the converted voltage into a reverse voltage, the reverse voltage being the opposite of the converted voltage. The input terminal of the voltage follower unit 33 is connected to the output terminal of the voltage inversion unit 32, and the output terminal of the voltage follower unit 33 is connected to the second input terminal of the control module 4, and it is used to generate a sampled voltage based on the reverse voltage, the reverse voltage being the same magnitude as the sampled voltage.

[0089] Optionally, the voltage conversion unit 31 includes: a twenty-fifth capacitor C25, a twenty-seventh capacitor C27, a twentieth resistor R20, a twenty-ninth resistor R29, a thirty-third resistor R33, and a third operational amplifier U3.

[0090] The 25th capacitor R25 is connected between the output terminal of the voltage output module 2 and the input terminal of the voltage inverting unit 32. The 20th resistor R20 is connected in parallel with the 25th capacitor C25. The 27th capacitor C27 is connected between the second terminal of the 25th capacitor C25 and the ground terminal. The 29th resistor R29 and the 33rd resistor R33 are connected in series between the second terminal of the 25th capacitor C25 and the ground terminal. The voltage inverting unit 32 includes: the 21st resistor R21, the 22nd resistor R22, the 27th resistor R27, the 19th capacitor C19, the 22nd capacitor C22, the 28th capacitor C28, the 32nd capacitor C32, and the 33rd capacitor C33. The first terminal of the twenty-seventh resistor R27 is connected to the second terminal of the twenty-fifth capacitor C25. The second terminal of the twenty-seventh resistor R27 is connected to the inverting input terminal of the third operational amplifier U3. The twenty-second resistor R22 is connected between the non-inverting input terminal and the ground terminal of the third operational amplifier U3. The first power supply terminal of the third operational amplifier U3 is connected to the second power supply terminal. The nineteenth capacitor C19 and the twenty-second capacitor C22 are connected in parallel between the second power supply terminal and the ground terminal. The second power supply terminal of the third operational amplifier U3 is connected to the third power supply terminal. The thirty-second capacitor C32 and the thirty-third capacitor C33 are connected in parallel between the third power supply terminal and the ground terminal. The voltage follower unit 33 includes: the fourteenth resistor R14, the twenty-third resistor R23, the twenty-eighth resistor R28, and the fourth operational amplifier U4. The fourteenth resistor R14 is connected between the inverting input terminal and the output terminal of the fourth operational amplifier U4. The twenty-third resistor R23 is connected between the output terminal of the third operational amplifier U3 and the non-inverting input terminal of the fourth operational amplifier U4. The twenty-eighth resistor R28 is connected between the fifth power supply terminal and the non-inverting input terminal of the fourth operational amplifier U4. For example, the third power supply terminal can be used to provide a voltage of -12V, and the fifth power supply terminal can be used to provide a voltage of 5V.

[0091] Among them, the twentieth resistor R20, the twenty-ninth resistor R29, the thirty-third resistor R33, the twenty-fifth capacitor C25, and the twenty-seventh capacitor C27 are used to sample the voltage at the second output terminal of transformer TB1 and generate a converted voltage. The magnitude of the converted voltage is used to reflect the magnitude of the first positive voltage or the first negative voltage.

[0092] An inverter composed of resistor R21 (21st), resistor R22 (22nd), resistor R27 (27th), diode CR1 (1st), diode CR4 (4th), and operational amplifier U4 (4th) can reverse the converted voltage to an inverted voltage.

[0093] The 23rd resistor R23 can have the same resistance value as the 28th resistor R28. The 23rd resistor R23 and the 28th resistor R28 can divide the 5V voltage. The sampled voltage can be output by the fourth operational amplifier U4 and transmitted to the positive input terminal of the first operational amplifier U1 through the filter circuit composed of the 10th resistor R10 and the 13th capacitor C13.

[0094] Optionally, when the given voltage is greater than the preset voltage, the voltage output module 2 is used to adjust and output a first positive voltage according to the adjusted voltage. When the given voltage is less than or equal to the preset voltage, the voltage output module 2 is used to adjust and output a first negative voltage according to the adjusted voltage.

[0095] As mentioned above, when the given voltage represented by the comparison voltage is greater than the sampling voltage, the voltage at the second terminal of the second transistor T2 increases. Since the second terminal of the second transistor T2 is connected to the center tap of the transformer TB1, the input voltage of the transformer TB1 increases. At this time, the output voltage of the transformer TB1 also increases, thereby increasing the voltage across the fifteenth capacitor C15, which in turn increases the output voltage of the voltage output module until the given voltage is raised to the magnitude of the sampling voltage.

[0096] When the given voltage is less than the sampling voltage, the voltage at the second terminal of the second transistor T2 decreases, so the input voltage of transformer TB1 decreases. At this time, the voltage across the fifteenth capacitor C15 decreases, so the input voltage of transformer TB1 decreases. At this time, the output voltage of transformer TB1 also decreases, thereby causing the voltage across the fifteenth capacitor C15 to decrease, which in turn reduces the output voltage of the voltage output module until the given voltage is reduced to the size of the sampling voltage.

[0097] After adjusting the given voltage to the sampling voltage, the given voltage = sampling voltage = (5 - reverse voltage) / 2 = (5 + conversion voltage) / 2.

[0098] For example, the preset voltage can be 2.5V. When the given voltage is less than or equal to the preset voltage, the given voltage = sampling voltage = (5 + conversion voltage) / 2 ≤ 2.5. At this time, the conversion voltage is negative. Therefore, the voltage output by the voltage output module is also negative, and the voltage output module outputs the first negative voltage.

[0099] When the given voltage is greater than the preset voltage, the given voltage = sampling voltage = (5 + conversion voltage) / 2 > 2.5. At this time, the conversion voltage is positive, so the voltage output by the voltage output module is also positive, and the voltage output module outputs the first positive voltage.

[0100] Therefore, by using different given voltage values, the embodiments of the present invention achieve output control of the first positive voltage or the first negative voltage of the voltage output module, so that the voltage output module can output both positive and negative voltages, and can also adjust the first positive voltage or the first negative voltage according to the magnitude of the given voltage and the sampling voltage. This makes the present invention applicable to the focusing plate load of various X-ray sources that require power supply of different voltage values, thereby improving the applicability of the present invention.

[0101] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0102] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A control system for an adjustable bipolar two-stage focusing voltage for an X-ray source, characterized in that, include: The setting module is used to output a given voltage; A voltage output module, connected to the focusing plate load of the X-ray source, is used to output a first positive voltage or a first negative voltage to the focusing plate load of the X-ray source according to the magnitude of the given voltage; when the given voltage is greater than a preset voltage, the voltage output module outputs the first positive voltage; when the given voltage is less than or equal to the preset voltage, the voltage output module outputs the first negative voltage. A voltage feedback module, connected to the voltage output module, is used to generate a sampling voltage based on the first positive voltage or the first negative voltage; The control module is connected to the setting module and the voltage feedback module, and also to the voltage output module. It is used to generate an adjustment voltage based on the magnitude of the given voltage and the sampled voltage. The voltage output module is used to adjust the magnitude of the first positive voltage or the first negative voltage based on the adjustment voltage.

2. The control system for the adjustable bipolar two-stage focusing voltage of an X-ray source according to claim 1, characterized in that, The control module includes: a comparison unit and a control unit; The first input terminal of the comparison unit is connected to the output terminal of the setting module, the second input terminal of the comparison unit is connected to the output terminal of the voltage feedback module, and the output terminal of the comparison unit is connected to the input terminal of the control unit. The comparison unit is used to generate a comparison voltage based on the magnitude of the given voltage and the sampled voltage. The output terminal of the control unit is connected to the voltage output module, and the control unit is used to generate an adjustment voltage based on the comparison voltage.

3. The control system for the adjustable bipolar secondary focusing voltage of an X-ray source according to claim 2, characterized in that, The comparison unit includes: a first comparator, a first resistor, a third resistor, a fourth resistor, a tenth resistor, a first capacitor, a fourth capacitor, a fifth capacitor, and a thirteenth capacitor; The fourth resistor is connected between the output terminal of the setting module and the inverting input terminal of the first comparator; the fourth capacitor and the third resistor are connected in series between the first and second terminals of the fourth resistor; the fifth capacitor is connected between the inverting input terminal and the output terminal of the first comparator; the first capacitor and the first resistor are connected in series between the first and second terminals of the fifth capacitor. The tenth resistor is connected between the positive input terminal of the first comparator and the output terminal of the voltage feedback module; the first terminal of the thirteenth capacitor is connected to the positive input terminal of the first comparator; and the second terminal of the thirteenth capacitor is grounded. The first comparator generates a comparison voltage based on the magnitude of the given voltage and the sampled voltage.

4. The control system for the adjustable bipolar secondary focusing voltage of an X-ray source according to claim 3, characterized in that, The control unit includes: a first transistor, a second transistor, a second resistor, a seventh resistor, an eleventh resistor, a second capacitor, a third capacitor, an eighth capacitor, an eleventh capacitor, and a twelfth capacitor; The first end of the seventh resistor is connected to the output terminal of the first comparator, the second end of the seventh resistor is connected to the control terminal of the first transistor, the eleventh resistor and the eleventh capacitor are both connected between the control terminal and the ground terminal of the first transistor, the eighth capacitor is connected between the first end of the first transistor and the ground terminal, the second end of the first transistor is grounded, the first end of the first transistor is connected to the second end of the second resistor, the first end of the second resistor is connected to the first end of the second transistor, the control terminal of the second transistor is connected to the first end of the first transistor, the twelfth capacitor is connected between the second end of the second transistor and the ground terminal; the first end of the second transistor is also connected to the first power supply terminal, and the second capacitor and the third capacitor are both connected between the first power supply terminal and the ground terminal.

5. The control system for the adjustable bipolar secondary focusing voltage of an X-ray source according to claim 1, characterized in that, The setting module includes: a second operational amplifier, a sixth resistor, a ninth resistor, and a tenth capacitor; The inverting input of the second operational amplifier is connected to its output. The output of the second operational amplifier is also connected to the first input of the control module. The non-inverting input of the second operational amplifier is connected to the second terminal of the sixth resistor. The first terminal of the sixth resistor is connected to the first terminal of the ninth resistor. The second terminal of the ninth resistor is connected to ground. The second terminal of the sixth resistor is connected to the first terminal of the tenth capacitor. The second terminal of the tenth capacitor is connected to ground. The first terminal of the sixth resistor is used to receive a set voltage. The second operational amplifier is used to generate the given voltage based on the set voltage. The set voltage and the given voltage are equal in magnitude. When the given voltage is greater than the preset voltage, the voltage output module is used to adjust and output the first positive voltage according to the adjusted voltage; When the given voltage is less than or equal to the preset voltage, the voltage output module is used to adjust and output the first negative voltage according to the adjustment voltage.

6. The control system for the adjustable bipolar secondary focusing voltage of an X-ray source according to claim 1, characterized in that, The voltage output module includes a pulse width modulation unit and a boost unit. The pulse width modulation unit is connected to the second power supply terminal. The pulse width modulation unit is used to alternately output a first modulation voltage and a second modulation voltage. The voltage waveforms of the first modulation voltage and the second modulation voltage are symmetrical. The boost unit is connected to the pulse width modulation unit and is used to receive the first modulation voltage and the second modulation voltage, and output a first positive voltage or a first negative voltage.

7. The control system for the adjustable bipolar secondary focusing voltage of an X-ray source according to claim 6, characterized in that, The pulse width modulation unit includes: Pulse width modulation chip, fifth resistor, eighth resistor, twelfth resistor, thirteenth resistor, seventeenth resistor, eighteenth resistor, nineteenth resistor, twenty-fourth resistor, twenty-fifth resistor, twenty-sixth resistor, thirtieth resistor, thirty-first resistor, thirty-second resistor, thirty-fourth resistor, sixth capacitor, ninth capacitor, fourteenth capacitor, sixteenth capacitor, eighteenth capacitor, twentieth capacitor, twenty-third capacitor, twenty-sixth capacitor, twenty-ninth capacitor, thirty-first capacitor, first switching transistor and second switching transistor; The first, second, and twelfth pins of the pulse width modulation chip are connected to the ground terminal, the fifth and seventh pins of the pulse width modulation chip are connected to the ground terminal through the eighteenth capacitor, and the sixth pin of the pulse width modulation chip is connected to the ground terminal through the eighteenth resistor. The 26th resistor, the 32nd resistor, and the 34th resistor are connected in series between the 16th pin of the pulse width modulation chip and the ground terminal. The 15th pin of the pulse width modulation chip is connected to the second power supply terminal. The 9th capacitor is connected between the second power supply terminal and the ground terminal. The 6th capacitor is connected between the 16th pin of the pulse width modulation chip and the second terminal of the 9th capacitor. The fourteenth pin of the pulse width modulation chip is connected to the control terminal of the first switching transistor through the eighth resistor. The twelfth resistor is connected between the control terminal and the second terminal of the first switching transistor. The first terminal of the first switching transistor is connected to the first input terminal of the boost unit. The fifth resistor and the fourteenth capacitor are connected in series between the first terminal of the first switching transistor and the ground terminal. The thirteenth pin of the pulse width modulation chip is connected to the thirteenth resistor, the sixteenth capacitor, and the twentieth capacitor. The second end of the thirteenth resistor is connected to the second power supply terminal, and the second ends of the sixteenth capacitor and the twentieth capacitor are connected to the ground terminal. The eleventh pin of the pulse width modulation chip is connected to the control terminal of the second switching transistor through the nineteenth resistor. The twenty-fourth resistor is connected between the control terminal and the second terminal of the second switching transistor. The second terminal of the twenty-fourth resistor is also connected to the second terminal of the twelfth resistor. The first terminal of the second switching transistor is connected to the second input terminal of the boost unit. The seventeenth resistor and the twenty-third capacitor are connected in series between the first terminal of the second switching transistor and the ground terminal. The tenth pin of the pulse width modulation chip is connected to the first end of the twenty-ninth capacitor, the thirty-first capacitor, the thirty-first resistor, and the thirty-second resistor, and the second end of the twenty-ninth capacitor, the thirty-first capacitor, and the thirty-second resistor is connected to the ground terminal. The ninth pin of the pulse width modulation chip is connected to the ground terminal through the thirty-first resistor, and is also connected to the first terminal of the twenty-sixth resistor through the twenty-fifth resistor.

8. The control system for the adjustable bipolar secondary focusing voltage of an X-ray source according to claim 7, characterized in that, The boost unit includes: a transformer, a seventh capacitor, a fifteenth capacitor, a thirty-fifth capacitor, a second diode, and a third diode; The first input terminal of the transformer is connected to the first terminal of the first switching transistor, the second input terminal of the transformer is connected to the first terminal of the second switching transistor, and the third input terminal of the transformer is connected to the output terminal of the control module. The first output terminal of the transformer is connected to the first terminal of the seventh capacitor, the second terminal of the seventh capacitor is connected to the first terminal of the second diode, and also to the second terminal of the third diode. The fifteenth capacitor is connected between the second terminal of the second diode and the first terminal of the third diode. The second output terminal of the transformer is connected to the first terminal of the fifteenth capacitor. The thirty-fifth capacitor is connected between the second terminal of the fifteenth capacitor and the ground terminal. The thirty-fifth capacitor is also connected in parallel with the fourth power supply. The second output terminal of the transformer is used to output the first positive voltage or the first negative voltage.

9. The control system for the adjustable bipolar secondary focusing voltage of an X-ray source according to claim 1, characterized in that, The voltage feedback module includes: a voltage conversion unit, a voltage inversion unit, and a voltage follower unit; The input terminal of the voltage conversion unit is connected to the output terminal of the voltage output module, and the voltage conversion unit is used to generate a conversion voltage based on the first positive voltage or the first negative voltage. The input terminal of the voltage inversion unit is connected to the output terminal of the voltage conversion unit, and is used to convert the converted voltage into an inverted voltage, wherein the inverted voltage and the converted voltage are opposites of each other; The input terminal of the voltage follower unit is connected to the output terminal of the voltage inversion unit, and the output terminal of the voltage follower unit is connected to the second input terminal of the control module, for generating the sampling voltage based on the inverted voltage, wherein the inverted voltage is the same magnitude as the sampling voltage.

10. The control system for the adjustable bipolar secondary focusing voltage of an X-ray source according to claim 9, characterized in that, The voltage conversion unit includes: a 25th capacitor, a 27th capacitor, a 20th resistor, a 29th resistor, a 33rd resistor, and a third operational amplifier; The 25th capacitor is connected between the output terminal of the voltage output module and the input terminal of the voltage inverting unit; the 20th resistor is connected in parallel with the 25th capacitor; and the 27th capacitor is connected between the second terminal of the 25th capacitor and the ground terminal. The 29th resistor and the 33rd resistor are connected in series between the second terminal of the 25th capacitor and the ground terminal; The voltage reversing unit includes: a 21st resistor, a 22nd resistor, a 27th resistor, a 19th capacitor, a 22nd capacitor, a 28th capacitor, a 32nd capacitor, and a 33rd capacitor; The first end of the 27th resistor is connected to the second end of the 25th capacitor, the second end of the 27th resistor is connected to the inverting input of the third operational amplifier, the 22nd resistor is connected between the non-inverting input of the third operational amplifier and the ground terminal, the first power supply terminal of the third operational amplifier is connected to the second power supply terminal, the 19th capacitor and the 22nd capacitor are connected in parallel between the second power supply terminal and the ground terminal; the second power supply terminal of the third operational amplifier is connected to the third power supply terminal, and the 32nd capacitor and the 33rd capacitor are connected in parallel between the third power supply terminal and the ground terminal; The voltage follower unit includes: a fourteenth resistor, a twenty-third resistor, a twenty-eighth resistor, and a fourth operational amplifier; The fourteenth resistor is connected between the inverting input and output of the fourth operational amplifier, the twenty-third resistor is connected between the output of the third operational amplifier and the non-inverting input of the fourth operational amplifier, and the twenty-eighth resistor is connected between the fifth power supply terminal and the non-inverting input of the fourth operational amplifier.

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