Radio frequency cavity tuning control device and method

Abstract

The invention discloses a radio frequency cavity tuning control device and method. The device comprises a cavity frequency detection unit, a tuning control unit, a frequency coarse tuning unit and a frequency fine tuning unit, the cavity frequency detection unit is used for collecting a radio frequency cavity resonant frequency signal of the radio frequency cavity and outputting the signal to the tuning control unit; the tuning control unit is used for obtaining a frequency difference according to the radio frequency cavity resonant frequency signal and a target resonant frequency signal, generating a corresponding tuning signal according to the frequency difference and outputting the tuning signal to the frequency coarse tuning unit and the frequency fine tuning unit; the frequency coarse adjustment unit is used for acting on the radio frequency cavity during working and is also used for preliminarily adjusting the resonant frequency of the radio frequency cavity; and the frequency fine adjustment unit is used for acting on the radio frequency cavity during working and is also used for finely adjusting the resonant frequency of the radio frequency cavity. According to the invention, the resonant frequency of the radio frequency cavity is adjusted by adopting a scheme of combining two modes of coarse adjustment and fine adjustment, and large-range and high-precision control of the resonant frequency of the radio frequency cavity is realized.

Description

Technical Field

[0001] This invention relates to the field of particle accelerator technology, and more particularly to a radio frequency cavity tuning control device and method. Background Technology

[0002] The radio frequency (RF) cavity is the core component of a particle accelerator, providing a stable high-frequency electromagnetic field for accelerating charged particle beams. During operation, the resonant frequency of the RF cavity can drift due to various disturbances, such as: mechanical disturbances (micro-deformation of the cavity caused by coolant pressure and flow fluctuations or external vibrations); thermal disturbances (thermal expansion / contraction of the cavity walls due to RF power loss or changes in ambient temperature); radiation pressure and Lorentz force detuning (radiation pressure generated by the strong electromagnetic field itself during high-power operation causes cavity deformation); and beam loading effects (energy is drawn from the cavity by the beam, causing changes in the cavity's equivalent parameters). Therefore, changes in the RF cavity frequency require higher energy injection to maintain the original RF accelerating field, which significantly increases the accelerator's operating costs.

[0003] To address this, existing solutions propose a dynamic tuning device that uses a motor as the tuning actuator, offering the advantage of a wide tuning range. However, the tuning control method based on a motor suffers from relatively low tuning accuracy due to the large operating range of the motor.

[0004] Therefore, existing technologies still need to be improved and developed. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a radio frequency cavity tuning control device and method to solve the problem of low tuning accuracy in existing radio frequency cavity tuning schemes.

[0006] The technical solution of the present invention is as follows: In a first aspect, the present invention provides a radio frequency cavity tuning control device, which includes: a cavity frequency detection unit, a tuning control unit, a frequency coarse tuning unit, and a frequency fine tuning unit; The cavity frequency detection unit is connected to the tuning control unit and is used to acquire the radio frequency cavity resonant frequency signal of the radio frequency cavity and output it to the tuning control unit; The tuning control unit is connected to the frequency coarse tuning unit and the frequency fine tuning unit respectively, and is used to obtain the frequency difference based on the RF cavity resonant frequency signal and the target resonant frequency signal, and generate a corresponding tuning signal based on the frequency difference and output it to the frequency coarse tuning unit and the frequency fine tuning unit. The frequency coarse adjustment unit is used to connect to the RF cavity and also to perform preliminary adjustment of the RF cavity resonant frequency. The frequency fine-tuning unit is used to connect to the radio frequency cavity and to finely adjust the resonant frequency of the radio frequency cavity.

[0007] In a further embodiment of the present invention, the cavity frequency detection unit includes: an IQ demodulator, a downconverter, and an ADC sampling unit; The IQ demodulator is used to demodulate the acquired radio frequency cavity resonant frequency signal using IQ demodulation. The downconverter is connected to the IQ demodulator and is used to convert the radio frequency cavity resonant frequency signal into an intermediate frequency signal. The ADC sampling unit is connected to the downconverter and the tuning control unit respectively, and is used to sample the resonant frequency signal of the radio frequency cavity and input it to the tuning control unit.

[0008] In a further embodiment of the present invention, the frequency coarse adjustment unit includes: a motor driver and a motor; The motor driver is connected to both the tuning control unit and the motor, and is used to output a drive current to drive the motor according to the tuning signal output by the tuning control unit. The motor is used to act on the radio frequency cavity during operation and to adjust the radio frequency cavity frequency according to the drive current.

[0009] In a further embodiment of the present invention, the driving current is a stepped wave.

[0010] In a further embodiment of the present invention, the frequency coarse adjustment unit further includes an optocoupler; the optocoupler is built into the motor driver and connected between the tuning control unit and the motor driver.

[0011] In a further embodiment of the present invention, the frequency fine-tuning unit includes: a piezoelectric ceramic driver and a piezoelectric ceramic; The piezoelectric ceramic driver is connected to the tuning control unit and the piezoelectric ceramic respectively, and is used to output a driving voltage to the piezoelectric ceramic according to the tuning signal; The piezoelectric ceramic is used to act on the radio frequency cavity during operation and to adjust the resonant frequency of the radio frequency cavity according to the driving voltage.

[0012] In a further embodiment of the present invention, the tuning signal includes an enable signal, a direction signal, and a pulse signal.

[0013] Secondly, the present invention also provides a radio frequency cavity tuning control method based on the radio frequency cavity tuning control device described above, the method comprising the following steps: Obtain the resonant frequency signal of the radio frequency cavity; The frequency difference is obtained based on the radio frequency resonant frequency signal and the target resonant frequency signal; Based on the frequency difference, coarse or fine tuning is selected and a corresponding tuning signal is generated to adjust the resonant frequency of the RF cavity to the target resonant frequency.

[0014] A further provision of the present invention includes the step of selecting coarse or fine tuning based on the frequency difference and generating a corresponding tuning signal to adjust the resonant frequency of the radio frequency cavity to the target resonant frequency, comprising: The resonant frequency signal of the radio frequency cavity is analyzed; When the frequency deviation is high-frequency and small-amplitude, the fine adjustment method is selected to adjust the resonant frequency of the RF cavity. When the frequency deviation is low and large, the coarse adjustment method is selected to adjust the resonant frequency of the RF cavity.

[0015] In a further embodiment of the present invention, the frequency coarse adjustment unit includes: a motor driver and a motor; the step of adjusting the resonant frequency of the RF cavity by selecting a coarse adjustment method when the frequency deviation is low frequency and large amplitude includes: The drive signal of the motor driver is subdivided to output a subdivided drive current to the motor; wherein the drive current is a stepped wave.

[0016] This invention provides a radio frequency cavity tuning control device and method. The device includes: a cavity frequency detection unit, a tuning control unit, a coarse frequency tuning unit, and a fine frequency tuning unit. The cavity frequency detection unit is connected to the tuning control unit and is used to acquire the radio frequency cavity resonant frequency signal and output it to the tuning control unit. The tuning control unit is connected to both the coarse and fine frequency tuning units and is used to obtain the frequency difference between the radio frequency cavity resonant frequency signal and the target resonant frequency signal, and generate a corresponding tuning signal based on the frequency difference, which is then output to the coarse and fine frequency tuning units. The coarse frequency tuning unit is connected to the radio frequency cavity and is also used to perform preliminary adjustment of the radio frequency cavity resonant frequency. The fine frequency tuning unit is connected to the radio frequency cavity and is also used to perform fine adjustment of the radio frequency cavity resonant frequency. This invention uses a combination of coarse and fine tuning methods to adjust the resonant frequency of the radio frequency cavity, achieving wide-range and high-precision control of the resonant frequency. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the radio frequency cavity tuning control device in this invention.

[0019] Figure 2 This is a schematic diagram of the signal isolation principle of the motor driver in this invention.

[0020] Figure 3 This is a schematic diagram of the motor microstepping control principle in this invention.

[0021] Figure 4 This is a schematic diagram of the non-divided drive current in this invention.

[0022] Figure 5 This is a schematic diagram of the drive current subdivision in this invention.

[0023] Figure 6 This is a schematic diagram of the control principle of the piezoelectric ceramic in this invention.

[0024] Figure 7 This is a flowchart illustrating the radio frequency cavity tuning control method of the present invention.

[0025] Figure 8 This is a flowchart of the fast-slow tuning control logic in one embodiment of the present invention.

[0026] The labels in the attached diagram are as follows: 1. Cavity frequency detection unit; 11. IQ demodulator; 12. Down-converter; 13. ADC sampling unit; 2. Tuning control unit; 3. Coarse frequency tuning unit; 31. Motor driver; 32. Motor; 33. Optocoupler; 4. Fine frequency tuning unit; 41. Piezoelectric ceramic driver; 42. Piezoelectric ceramic; 5. RF cavity. Detailed Implementation

[0027] This invention provides a radio frequency cavity tuning control device and method. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0028] In the implementation methods and claims, unless otherwise specified in the text, the terms "a," "an," "the," and "the" may also include plural forms. If the embodiments of the present invention involve descriptions of "first," "second," etc., such descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features.

[0029] It should be further understood that the term "comprising" as used in this specification means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that when an element is referred to as "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements present. Furthermore, "connected" or "coupled" as used herein can include wireless connections or wireless coupling. The term "and / or" as used herein includes all or any of the units and all combinations thereof of one or more associatedly listed items.

[0030] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined as herein.

[0031] Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0032] Please also refer to Figures 1 to 6 The present invention provides a preferred embodiment of a radio frequency cavity tuning control device.

[0033] In some embodiments, such as Figure 1 As shown, this invention provides a radio frequency cavity 5 tuning control device, comprising: a cavity frequency detection unit 1, a tuning control unit 2, a frequency coarse adjustment unit 3, and a frequency fine adjustment unit 4. The cavity frequency detection unit 1 is connected to the tuning control unit 2 and is used to acquire the resonant frequency signal of the radio frequency cavity 5 and output it to the tuning control unit 2. The tuning control unit 2 is connected to both the frequency coarse adjustment unit 3 and the frequency fine adjustment unit 4, and is used to obtain the frequency difference between the resonant frequency signal of the radio frequency cavity 5 and the target resonant frequency signal, and generate a corresponding tuning signal based on the frequency difference, which is then output to the frequency coarse adjustment unit 3 and the frequency fine adjustment unit 4. The frequency coarse adjustment unit 3 is used to act on the radio frequency cavity during operation and to perform preliminary adjustment of the resonant frequency of the radio frequency cavity 5. The frequency fine adjustment unit 4 is used to act on the radio frequency cavity during operation and to perform fine adjustment of the resonant frequency of the radio frequency cavity 5.

[0034] In this embodiment, the cavity frequency detection unit 1 is connected to the radio frequency cavity 5 and can acquire the current resonant frequency signal of the radio frequency cavity 5 and feed it back to the tuning control unit 2. The tuning control unit 2 can be an FPGA control circuit board. The frequency coarse adjustment unit 3 can perform coarse adjustment of the resonant frequency of the radio frequency cavity 5, meaning it can adjust the resonant frequency over a wide range with low precision. The frequency fine adjustment unit 4 can perform fine adjustment of the resonant frequency of the radio frequency cavity 5 over a small range with high precision.

[0035] The tuning control unit 2 receives the target resonant frequency signal of the radio frequency cavity 5 and can calculate the frequency difference between the currently acquired resonant frequency signal of the radio frequency cavity 5 and the target resonant frequency signal. Therefore, it can select either the coarse frequency adjustment unit 3 to adjust the resonant frequency of the radio frequency cavity 5, or the fine frequency adjustment unit 4 to adjust the resonant frequency of the radio frequency cavity 5. In other words, it can choose to perform coarse adjustment first and then fine adjustment, or it can perform coarse adjustment directly. For example, the tuning control unit 2 first outputs a motor control signal to control the motor to perform coarse adjustment of the radio frequency cavity 5. After the resonant frequency of the radio frequency cavity 5 approaches the target resonant frequency, the tuning control unit 2 outputs a piezoelectric ceramic 42 control signal to perform fine adjustment of the resonant frequency of the radio frequency cavity 5. The tuning signal includes an enable signal, a direction signal, and a pulse signal, etc.

[0036] In the above technical solution, the present invention acquires the resonant frequency signal of the radio frequency cavity 5, compares the currently acquired resonant frequency signal of the radio frequency cavity 5 with the target resonant frequency signal, and makes a judgment, so that the resonant adjustment unit outputs the corresponding tuning signal to the frequency coarse adjustment unit 3 or the frequency fine adjustment unit 4, thereby realizing the adjustment of the resonant frequency of the radio frequency cavity 5 over a wide range and with high precision. Thus, when adjusting the resonant frequency of the radio frequency cavity 5, both adjustment efficiency and adjustment accuracy are guaranteed.

[0037] In some embodiments, such as Figure 1 As shown, the cavity frequency detection unit 1 includes: an IQ demodulator 11, a downconverter 12, and an ADC sampling unit 13; wherein, the IQ demodulator 11 is used to demodulate the acquired radio frequency cavity resonant frequency signal; the downconverter 12 is connected to the IQ demodulator 11 and is used to convert the radio frequency cavity resonant frequency signal into an intermediate frequency signal; the ADC sampling unit 13 is connected to the downconverter 12 and the tuning control unit 2 respectively, and is used to sample the radio frequency cavity resonant frequency signal and input it to the tuning control unit 2.

[0038] In this embodiment, the resonant frequency of the radio frequency cavity 5 is generally around 1.3 GHz. The radio frequency signal of the radio frequency cavity 5 is led out from the radio frequency cavity 5 through the radio frequency cable and sent to the IQ demodulator 11. The IQ demodulator 11 demodulates the acquired resonant frequency signal of the radio frequency cavity 5, and further mixes it through the downconverter 12 to reduce the resonant frequency signal of the radio frequency cavity 5 to an intermediate frequency signal. Then, it is acquired by the ADC acquisition unit and input to the tuning control unit 2.

[0039] In some embodiments, such as Figure 1 As shown, the frequency coarse adjustment unit 3 includes a motor driver 31 and a motor 32; the motor driver 31 is connected to the tuning control unit 2 and the motor 32 respectively, and is used to output a drive current to drive the motor according to the tuning signal output by the tuning control unit 2; the motor is used to act on the radio frequency cavity 5 during operation, and is used to adjust the frequency of the radio frequency cavity 5 according to the drive current.

[0040] In this embodiment, the frequency coarse adjustment unit 3 uses a motor 32 to achieve a wide range of adjustment. When the motor driver 31 receives the tuning control signal output by the tuning control unit 2, the motor driver 31 outputs a driving current to drive the motor to adjust the resonant frequency of the radio frequency cavity 5.

[0041] In some embodiments, such as Figure 1 and Figure 2 As shown, the frequency coarse adjustment unit 3 also includes an optocoupler 33; the optocoupler 33 is built into the motor driver and connected between the tuning control unit 2 and the motor driver 31.

[0042] In this embodiment, the motor driver 31 receives the tuning control signal through the optocoupler 33, which can achieve isolation between the control signal (low power) and the drive signal (high power) and avoid signal cross-interference.

[0043] In some embodiments, such as Figure 3 , Figure 4 and Figure 5 As shown, the driving current is a stepped wave.

[0044] In this embodiment, the motor driver 31 is equipped with a subdivision algorithm, which can subdivide the drive signal and output the subdivided drive current to the motor, so that the drive current changes from a square wave to a stepped wave. By using the subdivision algorithm to adjust the drive current into a stepped wave, the minimum movement distance of the motor is reduced to one-hundredth to one-ten-thousandth of the original distance.

[0045] It's important to understand that existing tuned motor controllers typically output a square wave current. The tuned motor's motion is a full-step motion. For commonly used two-phase stepper motors, this full-step motion results in a 1.8° rotation, leading to low tuning resolution and generating vibration and noise that affects the RF cavity 5's operating state. By subdividing the square wave current output by the motor driver 31 into a stepped wave, adding intermediate states, the motor's full-step motion is transformed into microstep motion. For commonly used two-phase stepper motors, this microstep motion results in a 1.8° / N rotation, significantly improving the tuning resolution. Taking a two-phase stepper motor as an example, without the subdivision algorithm, the current is as shown above. Figure 4 As shown, the motor operates "step by step," rotating 1.8° per step. When the microstepping algorithm is applied, assuming a microstepping value of 200, the motor rotates 1.8° / 200 = 0.009° per step. Therefore, using the microstepped drive current output to the motor, compared to the existing square wave output current, can improve the motor's positioning accuracy and reduce vibration and noise during motor movement. Furthermore, the continuously varying input current further reduces motor vibration and noise.

[0046] In some embodiments, a servo control scheme can also be used, where the controller provides the target position, the driver compares the actual position fed back by the encoder, and calculates the required current command. This can replace the subdivision scheme of motor control and provide more accurate positioning.

[0047] In some embodiments, such as Figure 1 and Figure 6 As shown, the frequency fine-tuning unit 4 includes a piezoelectric ceramic driver 41 and a piezoelectric ceramic 42. The piezoelectric ceramic driver 41 is connected to both the tuning control unit 2 and the piezoelectric ceramic 42, and is used to output a driving voltage to the piezoelectric ceramic 42 according to the tuning signal. The piezoelectric ceramic 42 acts on the radio frequency cavity 5 during operation and is used to adjust the resonant frequency of the radio frequency cavity 5 according to the driving voltage.

[0048] In this embodiment, the frequency fine-tuning unit 4 uses a piezoelectric ceramic 42 to achieve fine frequency adjustment of the radio frequency cavity 5. When the piezoelectric ceramic driver 41 receives a tuning signal, it outputs a driving voltage to the piezoelectric ceramic 42 to control the piezoelectric ceramic 42 to extend and retract onto the radio frequency cavity 5, thereby achieving fast and accurate tuning of the radio frequency cavity 5.

[0049] In some embodiments, the frequency fine-tuning unit 4 can also employ a fast-tuning actuator (such as a novel piezoelectric material or magnetostrictive material) with higher bandwidth and a larger dynamic range, in conjunction with model predictive control, adaptive filtering, or a deep learning controller. The algorithm can predict disturbance trends and provide more accurate compensation before or during disturbance occurrence. This approach expands the effective compensation bandwidth of fast tuning, enabling it to handle disturbances that originally belonged to the slow-tuning frequency band.

[0050] In some embodiments, such as Figure 7 As shown, the present invention also provides a radio frequency cavity tuning control method based on the radio frequency cavity tuning control device described above, the method comprising the following steps: S100: Obtain the radio frequency cavity resonant frequency signal of the radio frequency cavity; S200. Obtain the frequency difference based on the radio frequency resonant frequency signal and the target resonant frequency signal; S300: Select coarse or fine adjustment based on the frequency difference and generate a corresponding tuning signal to adjust the resonant frequency of the radio frequency cavity to the target resonant frequency.

[0051] In this embodiment, the tuning control unit controls the cavity frequency acquisition unit to acquire the resonant frequency signal of the RF cavity. The tuning control unit receives the target resonant frequency signal of the RF cavity and can calculate the frequency difference between the currently acquired RF cavity resonant frequency signal and the target resonant frequency signal. Based on this frequency difference, it can select either a coarse frequency adjustment unit to adjust the resonant frequency of the RF cavity, or a fine frequency adjustment unit to adjust the resonant frequency of the RF cavity, so that the resonant frequency of the RF cavity is adjusted to the target resonant frequency. For example, the tuning control unit first outputs a motor control signal to control the motor to coarsely adjust the RF cavity. After the resonant frequency of the RF cavity approaches the target resonant frequency, the tuning control unit outputs a piezoelectric ceramic control signal to finely adjust the resonant frequency of the RF cavity. This invention can achieve a wide range and high precision adjustment of the resonant frequency of the RF cavity, thus ensuring both adjustment efficiency and adjustment accuracy when adjusting the resonant frequency of the RF cavity.

[0052] In some embodiments, the step of selecting coarse or fine tuning based on the frequency difference and generating a corresponding tuning signal to adjust the radio frequency cavity resonant frequency to the target resonant frequency includes: S310. Analyze the resonant frequency signal of the radio frequency cavity; S320. When the frequency deviation is high-frequency and small-amplitude, the fine adjustment method is selected to adjust the resonant frequency of the RF cavity. S330. When the frequency deviation is low or large, select the coarse adjustment method to adjust the resonant frequency of the RF cavity.

[0053] In this embodiment, please refer to Figure 8 The tuning control unit compares the currently acquired RF cavity resonant frequency signal with the target resonant frequency signal, calculates the frequency difference, and analyzes the frequency deviation. When the frequency deviation is high-frequency and small-amplitude, the frequency fine-tuning unit (piezoelectric ceramic) is driven to quickly tune through the fast tuning channel; when the frequency deviation is low-frequency and large-amplitude, the frequency coarse-tuning unit (motor) is driven to perform wide-range tuning through the slow tuning channel.

[0054] In some embodiments, the frequency coarse adjustment unit includes: a motor driver and a motor; the step of adjusting the resonant frequency of the RF cavity by selecting a coarse adjustment method when the frequency deviation is low frequency and large amplitude includes: S331. The drive signal of the motor driver is subdivided to output a subdivided drive current to the motor; wherein the drive current is a stepped wave.

[0055] In this embodiment, the motor driver is equipped with a subdivision algorithm that can subdivide the drive signal and output the subdivided drive current to the motor, changing the drive current from a square wave to a stepped wave. By using the subdivision algorithm to adjust the drive current into a stepped wave, the minimum movement distance of the motor is reduced to a few hundred to tens of thousands of times the original distance, thereby improving the positioning accuracy of the motor and reducing vibration and noise during motor movement.

[0056] In summary, the radio frequency cavity tuning control device and method provided by the present invention have the following beneficial effects: The fast-slow tuning method has the ability to suppress both low-frequency and high-frequency components of detuning, achieving a balance between the tuning range and tuning accuracy of the superconducting cavity and ensuring the stability of the resonant frequency during the operation of the radio frequency cavity. Frequency deviation analysis is performed based on the measured cavity frequency, and the frequency deviation is classified into two types: high frequency and small amplitude, and low frequency and large amplitude. For different types of frequency deviation, the corresponding fast tuning or slow tuning channel is selected, and then the corresponding fast tuning or slow tuning mechanism is driven to complete the RF cavity frequency tuning. That is, the tuning control logic can select the appropriate tuning method for different frequency deviations, thereby improving tuning efficiency and tuning accuracy. This reduces motor vibration and noise during tuning, improves the positioning accuracy of the tuning motor, and the continuously varying input current also reduces motor vibration and noise.

[0057] It should be understood that the application of the present invention is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A radio frequency cavity tuning control device, characterized in that, include: Cavity frequency detection unit, tuning control unit, coarse frequency tuning unit, and fine frequency tuning unit; The cavity frequency detection unit is connected to the tuning control unit and is used to acquire the radio frequency cavity resonant frequency signal of the radio frequency cavity and output it to the tuning control unit; The tuning control unit is connected to the frequency coarse tuning unit and the frequency fine tuning unit respectively, and is used to obtain the frequency difference based on the RF cavity resonant frequency signal and the target resonant frequency signal, and generate a corresponding tuning signal based on the frequency difference and output it to the frequency coarse tuning unit and the frequency fine tuning unit. The frequency coarse adjustment unit is used to act on the radio frequency cavity during operation, and is also used to perform preliminary adjustment of the radio frequency cavity resonant frequency. The frequency fine-tuning unit is used to act on the radio frequency cavity during operation and to finely adjust the resonant frequency of the radio frequency cavity.

2. The radio frequency cavity tuning control device according to claim 1, characterized in that, The cavity frequency detection unit includes: an IQ demodulator, a downconverter, and an ADC sampling unit; The IQ demodulator is used to demodulate the acquired radio frequency cavity resonant frequency signal using IQ demodulation. The downconverter is connected to the IQ demodulator and is used to convert the radio frequency cavity resonant frequency signal into an intermediate frequency signal. The ADC sampling unit is connected to the downconverter and the tuning control unit respectively, and is used to sample the resonant frequency signal of the radio frequency cavity and input it to the tuning control unit.

3. The radio frequency cavity tuning control device according to claim 1, characterized in that, The frequency coarse adjustment unit includes: a motor driver and a motor; The motor driver is connected to both the tuning control unit and the motor, and is used to output a drive current to drive the motor according to the tuning signal output by the tuning control unit. The motor is used to act on the radio frequency cavity during operation and to adjust the radio frequency cavity frequency according to the drive current.

4. The radio frequency cavity tuning control device according to claim 3, characterized in that, The driving current is a stepped wave.

5. The radio frequency cavity tuning control device according to claim 3, characterized in that, The frequency coarse adjustment unit also includes an optocoupler; the optocoupler is built into the motor driver and connected between the tuning control unit and the motor driver.

6. The radio frequency cavity tuning control device according to claim 1, characterized in that, The frequency fine-tuning unit includes: a piezoelectric ceramic driver and a piezoelectric ceramic; The piezoelectric ceramic driver is connected to the tuning control unit and the piezoelectric ceramic respectively, and is used to output a driving voltage to the piezoelectric ceramic according to the tuning signal; The piezoelectric ceramic is used to act on the radio frequency cavity during operation and to adjust the resonant frequency of the radio frequency cavity according to the driving voltage.

7. The radio frequency cavity tuning control device according to claim 1, characterized in that, The tuning signals include an enable signal, a direction signal, and a pulse signal.

8. A radio frequency cavity tuning control method based on the radio frequency cavity tuning control device according to any one of claims 1-7, characterized in that, The method includes the following steps: Obtain the resonant frequency signal of the radio frequency cavity; The frequency difference is obtained based on the radio frequency resonant frequency signal and the target resonant frequency signal; Based on the frequency difference, coarse or fine tuning is selected and a corresponding tuning signal is generated to adjust the resonant frequency of the RF cavity to the target resonant frequency.

9. The radio frequency cavity tuning control method according to claim 8, characterized in that, The step of selecting coarse or fine adjustment based on the frequency difference and generating a corresponding tuning signal to adjust the resonant frequency of the RF cavity to the target resonant frequency includes: The resonant frequency signal of the radio frequency cavity is analyzed; When the frequency deviation is high-frequency and small-amplitude, the fine adjustment method is selected to adjust the resonant frequency of the RF cavity. When the frequency deviation is low and large, the coarse adjustment method is selected to adjust the resonant frequency of the RF cavity.

10. The radio frequency cavity tuning control method according to claim 8, characterized in that, The frequency coarse adjustment unit includes a motor driver and a motor; the step of adjusting the resonant frequency of the RF cavity by selecting a coarse adjustment method when the frequency deviation is low frequency and large amplitude includes: The drive signal of the motor driver is subdivided to output a subdivided drive current to the motor; wherein the drive current is a stepped wave.

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