Traveling wave accelerating tube automatic tuning and deploying system and method

Abstract

The invention discloses an automatic tuning and deploying system and method for a traveling wave accelerating tube, and belongs to the field of electron linear accelerators. The system comprises a motor control box, a motor and motion assembly, a temperature and humidity sensor, a network analyzer and an upper computer; the motor control box accurately controls the displacement of the motor to realize accurate positioning of the piston in the test cavity; the temperature and humidity sensor records parameters in an actual measurement environment, so that subsequent resonant frequency correction is facilitated; the network analyzer displays and records resonance signals and phase information of the coupling cavity and the accelerating cavity when the piston is located at different positions; and the upper computer corrects the resonant frequency in real time, calculates the inter-cavity phase shift and the accumulated phase difference, and graphically displays and stores the data. The system provided by the invention can automatically and accurately complete the processes of cavity positioning, signal acquisition, phase analysis and the like, realizes rapid and automatic tuning and deployment of the traveling wave acceleration structure, is simple and efficient in operation, can effectively reduce manual errors, and improves the precision.

Description

Technical Field

[0001] This invention belongs to the field of electron linear accelerators, and more specifically, relates to an automatic tuning and adjustment system and method for traveling wave accelerator tubes. Background Technology

[0002] An electron linear accelerator is a highly efficient particle acceleration device that focuses and accelerates electron beams using radio frequency electromagnetic fields, achieving higher performance and applications in scientific research, industry, and medicine. Currently, electron linear accelerators are evolving towards higher acceleration gradients and more compact structures, finding wide applications in high-energy physics, industrial detection, medical treatment, and irradiation processing. In scientific research, high-energy, high-brightness electron beams can be used in large-scale devices such as free-electron lasers, electron-positron colliders, and synchrotron radiation sources. In engineering applications, high-energy output can be achieved within confined spaces, making it suitable for non-destructive testing, radiotherapy, isotope preparation, and material surface treatment.

[0003] Traveling wave tubes are an important component of electron linear accelerators, and their performance largely depends on the accuracy of the cavity resonant frequency and whether the phase shift between the accelerating cavities meets the design requirements. Due to errors generated during manufacturing, assembly, and environmental influences, the resonant frequency and phase shift of the cavity usually deviate from the theoretical design. Therefore, tuning or adjustment is generally required after assembly.

[0004] Existing tuning methods rely on manual measurement of each cavity, frequent and repeated piston movements, and have a low degree of automation. They are also prone to insufficient tuning accuracy due to human error and inaccurate positioning. Summary of the Invention

[0005] In view of the above-mentioned defects or improvement needs of the existing technology, the present invention provides an automatic tuning and adjustment system and method for traveling wave accelerator tubes, thereby solving the technical problems of low automation and insufficient tuning accuracy of the existing tuning and adjustment methods.

[0006] To achieve the above objectives, according to a first aspect of the present invention, an automatic tuning and adjustment system for a traveling wave accelerator tube is provided, comprising: The motor and motion components include a first servo motor, a first screw, a carbon fiber rod, and a first precision displacement platform; the lower end of the precision displacement platform is connected to the screw and positioned above the screw, and the upper end is connected to one end of the carbon fiber rod, with a piston mounted on the other end of the carbon fiber rod; the output end of the first servo motor is coaxially connected to the first screw to drive the first screw to rotate, thereby driving the carbon fiber rod connected to the first precision displacement platform to produce a stepping movement, so that the piston located at the other end of the carbon fiber rod enters the target acceleration cavity in the traveling wave accelerator tube from one end of the traveling wave accelerator tube; The motor control box is used to control the operation of the first servo motor according to the control instructions from the host computer. Temperature and humidity sensors are used to measure ambient temperature and humidity and transmit the data to a host computer. The tuning and matching module is used to tune the target accelerating cavity or match the coupling cavity and power coupler. A network analyzer, connected to a power coupler located at the other end of the traveling wave accelerator tube, is used to read relevant information to a host computer after the piston reaches the center position of the target accelerator cavity and the power coupler injects energy into the traveling wave accelerator tube. During tuning, the relevant information includes the resonant frequency and phase of the target accelerator cavity; during adjustment, the relevant information includes the resonant frequency of the coupling cavity and the phase information of the operating frequency of the coupling cavity in different operating modes on the Smith chart. The host computer sequentially selects each accelerating cavity of the traveling wave accelerator tube as the target accelerating cavity. After tuning the target accelerating cavity through the tuning and matching module, the first servo motor is controlled by the motor control box to drive the piston to the center position of the target accelerating cavity. The resonant frequency of the target accelerating cavity is corrected according to the ambient temperature and humidity. The phase shift between adjacent accelerating cavities and the cumulative phase difference between all adjacent accelerating cavities are calculated according to the phase of the target accelerating cavity to obtain the tuning result. Alternatively, after the tuning and tuning module completes the tuning of the coupling cavity and the power coupler, the center position of the coupling cavity and the center position of the adjacent acceleration cavity are respectively used as the target position of the piston. The first servo motor is controlled by the motor control box to drive the piston to the target position. The resonant frequency of the coupling cavity is corrected according to the ambient temperature and humidity. The phase information of the operating frequency of the coupling cavity in different working modes on the Smith chart is received to obtain the tuning result.

[0007] According to a second aspect of the present invention, an automatic tuning method for a traveling-wave accelerator tube is provided, applied to the automatic tuning and adjustment system for a traveling-wave accelerator tube as described in the first aspect, comprising: S1, the host computer sequentially uses each acceleration cavity of the traveling wave accelerator tube as the target acceleration cavity. After tuning the target acceleration cavity through the tuning and adjustment module, it sends a control command to the motor control box. After receiving the control command, the motor control box controls the first servo motor to drive the precision displacement platform to the coordinate zero point position, and then drives the first servo motor to run, thereby driving the piston to reach the center position of the target acceleration cavity. S2, the temperature and humidity sensor measures the ambient temperature and humidity and forwards the data to the host computer; the power coupler injects energy into the traveling wave accelerator tube, and the network analyzer reads the resonant frequency and phase of the target accelerator cavity and forwards the data to the host computer; S3, the host computer corrects the resonant frequency of the target accelerating cavity according to the ambient temperature and humidity, calculates the inter-cavity phase shift and cumulative phase difference according to the phase of the target accelerating cavity, and obtains the tuning result. If the tuning result meets the standard, the process ends; otherwise, it returns to S1 until the tuning result meets the standard.

[0008] According to a third aspect of the present invention, an automatic tuning method for a traveling-wave accelerator tube is provided, applied to the automatic tuning and matching system for a traveling-wave accelerator tube as described in the first aspect, comprising: S1, after the host computer completes the tuning and adjustment of the coupling cavity and the power coupler through the tuning and adjustment module, it takes the center position of the coupling cavity and the center position of the adjacent acceleration cavity as the target position of the piston and sends a control command to the motor control box. After receiving the control command, the motor control box controls the first servo motor to drive the precision displacement platform to the coordinate zero point position, and then drives the first servo motor to run, thereby driving the piston to reach the target position. S2, the temperature and humidity sensor measures the ambient temperature and humidity and forwards the data to the host computer; the power coupler injects energy into the traveling wave accelerator tube; the network analyzer reads the resonant frequency of the coupling cavity and the phase information of the coupling cavity's operating frequency in different operating modes on the Smith chart and forwards it to the host computer. S3, the host computer corrects the resonant frequency of the coupling cavity according to the ambient temperature and humidity, receives the phase information of the operating frequency of the coupling cavity in different working modes on the Smith chart, and obtains the tuning result. If the tuning result meets the standard, the process ends; otherwise, it returns to S1 until the tuning result meets the standard.

[0009] In summary, compared with the prior art, the above-described technical solutions conceived by this invention can achieve the following beneficial effects: The automatic tuning and adjustment system for traveling wave accelerator tubes provided by this invention can achieve fully automated operation after the environmental temperature, humidity, and accelerator cavity position calibration data are imported. It can complete functions such as piston positioning, coupler and accelerator cavity resonant signal and phase information acquisition, data processing, and display without any manual intervention. It has advantages such as simple operation, reliable control, high precision, and high degree of automation, which can improve tuning accuracy and reduce human error. Specifically, this system has the following advantages: 1. This system achieves unified coordination through a host computer, enabling automatic control of the motor and reading data measured by the network analyzer. It has a high degree of automation, realizing full-process control and data processing without the need for manual intervention.

[0010] 2. Based on the frequency measurement error in a vacuum environment, the influence of ambient temperature and humidity on the frequency is considered, and the environmental compensation is accurate, improving the measurement consistency.

[0011] 3. The overall operation interface is simple and intuitive, easy to understand and differentiate, and directly calculates measurement results, reducing data processing time. It also displays results in real time and graphically, and can save data tables and graphs after measurement.

[0012] 4. This system can be used for tuning and measuring traveling wave accelerator tubes in the X-band and other frequency bands, and has a wide range of applications.

[0013] 5. The system's modules are connected via standard communication interfaces, facilitating maintenance and upgrades of each part and meeting the tuning and testing requirements of traveling wave accelerator tubes. Attached Figure Description

[0014] Figure 1 This is one of the schematic diagrams of the automatic tuning and adjustment system for traveling wave accelerator tubes provided in an embodiment of the present invention; Figure 2 This is the second schematic diagram of the automatic tuning and adjustment system for traveling wave accelerator tubes provided in an embodiment of the present invention; Figure 3 (a) and (b) are schematic diagrams of the tuning method and the tuning method provided in the embodiments of the present invention, respectively; wherein the tuning method is the short-circuit detuning method and the tuning method is the three-frequency method; Figure 4 This is a diagram of the host computer control program panel in the automatic tuning and adjustment system for traveling wave accelerator tubes provided in an embodiment of the present invention. Figure 5 This is a schematic flowchart of the automatic tuning and adjustment method for traveling wave accelerator tubes provided in an embodiment of the present invention. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0016] This invention provides an automatic tuning and adjustment system for traveling wave accelerator tubes, such as... Figure 1 As shown, it includes: The motor and motion components include a first servo motor, a screw, a carbon fiber rod, and a precision displacement platform. The lower end of the precision displacement platform is connected to the screw and positioned above it, while the upper end is connected to one end of the carbon fiber rod. A piston is mounted on the other end of the carbon fiber rod (i.e., the other end of the carbon fiber rod is connected to the piston). The output end of the first servo motor is coaxially connected to the screw to drive the screw to rotate, thereby causing the carbon fiber rod connected to the precision displacement platform to move in a stepping motion, so that the piston located at the other end of the carbon fiber rod enters the target acceleration cavity that enters the traveling wave accelerator tube from one end of the traveling wave accelerator tube. The motor control box is used to control the operation of the first servo motor according to the control instructions from the host computer. Temperature and humidity sensors are used to measure ambient temperature and humidity and transmit the data to a host computer. The tuning and matching module is used to tune the target accelerating cavity in the traveling wave accelerator tube or to match the coupling cavity and power coupler in the traveling wave accelerator tube. A network analyzer, connected to a power coupler located at the other end of the traveling wave accelerator tube, is used to read relevant information to a host computer after the piston reaches the center position of the target accelerator cavity and the power coupler injects energy into the traveling wave accelerator tube. During tuning, the relevant information includes the resonant frequency and phase of the target accelerator cavity; during adjustment, the relevant information includes the resonant frequency of the coupling cavity and the phase information of the operating frequency of the coupling cavity in different operating modes on the Smith chart. The host computer sequentially selects each accelerating cavity of the traveling wave accelerator tube as the target accelerating cavity. After tuning the target accelerating cavity through the tuning and adjustment module, it controls the first servo motor through the motor control box to drive the piston to the center position of the target accelerating cavity. It receives the resonant frequency and phase of the target accelerating cavity forwarded by the network analyzer, corrects the resonant frequency of the target accelerating cavity according to the ambient temperature and humidity, and calculates the inter-cavity phase shift between each adjacent accelerating cavity and the cumulative phase difference between all adjacent accelerating cavities based on the phase of the target accelerating cavity, thus obtaining the tuning result. That is, the tuning result includes the corrected resonant frequency of each accelerating cavity, the inter-cavity phase shift between each adjacent accelerating cavity, and the cumulative phase difference between all adjacent accelerating cavities. Alternatively, the host computer can adjust the coupling cavity and power coupler through the tuning and adjustment module, and then use the center position of the coupling cavity and the center position of the adjacent acceleration cavity as the target position of the piston. The first servo motor is controlled by the motor control box to drive the piston to the target position. The resonant frequency of the coupling cavity is corrected according to the ambient temperature and humidity, and the phase information of the operating frequency of the coupling cavity in different working modes on the Smith chart is received to obtain the tuning result.

[0017] Preferably, such as Figure 2As shown, the tuning and adjustment module includes a first and a second ejector pin, a second precision displacement platform, a second screw, a second, a third, and a fourth servo motor, and their respective motor controllers; The output end of the second servo motor is coaxially connected to the second screw, which drives the second screw to rotate, thereby causing the first and second ejector pins connected to the second precision displacement platform to move in a stepping manner, so that the first and second ejector pins reach the target acceleration cavity or coupling cavity. The third and fourth servo motors are respectively used to drive the first and second ejector pins to squeeze the target acceleration cavity or coupling cavity from different directions, thereby completing the tuning of the target acceleration cavity or the adjustment of the coupling cavity and power coupler.

[0018] The host computer controls the second servo motor through the controller of the second servo motor to drive the first and second ejector pins to the target acceleration cavity or coupling cavity. The host computer then controls the first and second ejector pins through the controllers of the third and fourth servo motors to squeeze the target acceleration cavity or coupling cavity from different directions, thereby completing the tuning of the target acceleration cavity or the adjustment of the coupling cavity and power coupler.

[0019] Specifically, in the tuning and adjustment module, the output end of the second servo motor is coaxially connected to the second screw, which drives the second screw to rotate, thereby causing the ejector device (including the first ejector and the second ejector) connected to the second precision displacement platform to produce step-by-step movement, so that the first ejector and the second ejector can be accurately displaced to the target cavity; then, the third and fourth servo motors (connected to...) Figure 2 The blue sections in the middle drive the third and fourth ejector pins to make subtle movements, which in turn cause the third and fourth ejector pins to compress the target acceleration cavity or coupling cavity from different directions, thereby adjusting the size of the target acceleration cavity or coupling cavity and the power coupler. Simultaneously, the network analyzer reads the resonant frequency and phase information of the target acceleration cavity or coupling cavity, and the results are processed by the host computer to obtain the tuning or adjustment results.

[0020] host computer according to The measured resonant frequency of the target accelerating cavity or coupling cavity After correction, the resonant frequency of the target accelerating cavity or coupling cavity is obtained. : in, , , , , , These are the resonant frequencies of the cavity (target acceleration cavity or coupling cavity) under vacuum and atmospheric conditions, respectively. It is the relative permittivity of air under the test conditions. This refers to the frequency change caused when the test temperature differs from the cavity's operating temperature. and At a certain temperature T At that time, the partial pressure occupied by dry gas and water vapor, T This refers to absolute temperature (i.e., ambient temperature). H For air humidity, This represents the saturated vapor pressure corresponding to the ambient humidity. It is the rate of change of the resonant frequency of the accelerating structure with the temperature of the cavity. It is the difference between the working temperature of the cavity and the test temperature.

[0021] Preferably, the motor control box includes: The zero-return module is used to control the first servo motor to move the precision displacement platform to the coordinate zero point position after receiving the control command sent by the host computer, thus completing the zero-return operation of the first servo motor. The first servo motor drive board is used to convert the control commands sent by the host computer into pulse signals to drive the first servo motor to run, thereby driving the piston to reach the center position or target position of the target acceleration chamber. The encoder signal processing module is used to compare the current running position of the first servo motor with the specified position (the correspondence between the center of the target acceleration cavity, i.e. the position that the piston needs to reach, and the target position that the motor needs to reach is established in advance), and to make up for the deviation through negative feedback, so as to perform closed-loop control of the first servo motor.

[0022] The system provided by this invention can achieve fully automated operation after importing ambient temperature and humidity data and acceleration chamber position calibration data (to the host computer). It can perform functions such as piston positioning, acquisition of resonant signals and phase information of the target acceleration chamber or coupling chamber, data processing, and display without any manual intervention. The system consists of a motor control box, a motor and motion components, temperature and humidity sensors, a network analyzer, and host computer control software. The motor control box integrates power supply, communication, first servo motor drive, encoder feedback, and infrared sensor into one unit, with a high degree of integration, which can efficiently support motor movement; the motor and motion components include the first servo motor, screw, carbon fiber rod, and precision displacement platform, which are used to accurately and stably drive the piston to move precisely along the central axis of the cavity in the traveling wave acceleration tube. Temperature and humidity sensors are used to monitor ambient temperature and humidity in real time, which facilitates the subsequent correction of the cavity's resonant frequency by the host computer. In addition, temperature differences in materials during processing and testing can also cause slight thermal expansion of the cavity. Therefore, the host computer corrects the resonant frequency of the cavity (target acceleration cavity or coupling cavity) by measuring ambient temperature and humidity, and uses the corrected resonant frequency as a test reference point.

[0023] The network analyzer can measure the resonant signal and phase data when the piston is in different positions in the cavity; that is, after the network analyzer is connected to the traveling wave accelerator tube, it is also connected to the host computer through the network interface. It can collect information such as the resonant frequency and phase in the cavity (target accelerator cavity or coupling cavity) and forward it to the host computer, which then analyzes the resonant characteristics and phase distribution of the cavity.

[0024] The host computer ensures the coordinated operation of all modules in the control system, enabling functions such as specifying motor position, automatic measurement, data processing, and result display. Specifically, the host computer implements a complete automated tuning process, featuring real-time motor position monitoring, motion status display, software emergency stop, and zero-return functionality. It automatically reads the resonant frequency and phase data of the test cavity (target acceleration cavity or coupling cavity) collected by the network analyzer, and calculates and corrects the resonant frequency of the test cavity by combining it with imported temperature and humidity data. It also calculates the inter-cavity phase shift and cumulative phase difference data. The processed data results are visualized in tables and graphs, facilitating the assessment of the tuning or adjustment results' rationality and compliance with requirements. The host computer ensures coordinated, stable, and automated operation of all parts, allowing for the next measurement step without manual intervention.

[0025] The host computer, combined with the motor drive control unit, network analyzer, and temperature and humidity sensors, can realize functions such as system coordination, motor control, data acquisition, data processing, graphic display, and storage, ensuring stable and automated system operation and reducing manual processing.

[0026] The system provided by this invention employs a first servo motor with encoder feedback function. The motor control method is pulse control plus position closed-loop feedback to ensure precise motor positioning. The output end of the motor is coaxially connected to a screw, and the rotation of the screw drives a precision displacement platform on it to move in steps. A carbon fiber rod is connected to the platform, and a piston is assembled at the end. The carbon fiber rod has the characteristics of slender structure, strong insulation and low deformation, which can complete the measurement by allowing the piston to penetrate to the designated position in each cavity of the accelerator tube without affecting the electromagnetic field distribution in the cavity. Preferably, the motor, screw, precision displacement platform and traveling wave accelerator tube are strictly coaxially arranged along the central axis of the traveling wave accelerator tube during installation, which effectively reduces the lateral displacement of the piston during measurement and significantly improves the measurement accuracy.

[0027] The motor control box has an integrated structure, including: The zero-return module is used to perform a motor zero-return operation after receiving the control command from the host computer, so that the motor drives the displacement platform to move to the infrared sensor and use it as the zero point to ensure that the coordinate zero point position of the motor remains unchanged every time it runs. The first servo motor drive board is used to convert the position signal (i.e., control command) designed by the host computer into a suitable pulse signal to drive the motor to the specified position; the encoder signal processing module can compare the motor running position signal with the specified position signal, and use negative feedback to make up for the deviation, so as to ensure the precise operation of the motor. The power supply and overcurrent protection module is used to provide a stable and reliable drive power for the first servo motor, reduce the error during motor operation, and enable real-time data interaction with the host computer communication interface.

[0028] The high degree of integration of the motor control box makes the system structure compact, simplifies wiring, reduces electromagnetic interference, improves system response speed, and ensures the stability and consistency of the entire tuning platform during long-term operation.

[0029] In other words, the motor control box includes a power module, a communication module, a motor driver, an encoder feedback processing module, an infrared limit switch, etc., with a high degree of integration. It is connected to the host computer through a network interface, and the host computer controls the first servo motor to drive the piston to move, so as to achieve precise positioning. The motor control implements position encoding feedback, which can ensure the repeatability of the motion. The infrared sensor ensures a constant zero coordinate when the motor is running, which facilitates the consistency of each run.

[0030] After fixing the traveling wave accelerating tube, precise measurements are performed based on a precision displacement platform. The position data of each cavity is imported into the host computer control system, enabling the piston to automatically and accurately move to the center of the test cavity for measurement.

[0031] Among them, the coupler is tuned based on the three-frequency method, and the accelerating cavity is tuned based on the short-circuit detuning method. Both methods use a piston as a short-circuit piston when the coupler is fed with power to simulate a reflecting surface, thereby extracting the resonant frequency and phase information of the test cavity.

[0032] like Figure 3 As shown in (a), when tuning using the short-circuit detuning method, the piston is moved one cavity at a time, the reflected wave is measured, the cavity resonant frequency is obtained, and the inter-cavity phase shift and cumulative phase shift are obtained according to the phase distribution. By correcting the cavity resonant frequency and the phase shift of each cavity to be equal to the designed working mode, the tuning can be completed.

[0033] like Figure 3 As shown in (b), when using the three-frequency method for tuning, the resonant frequency of the coupling cavity of the traveling wave accelerator tube is measured, and the coupling cavity is used in different operating modes. , Operating frequency , Phase information on the Smith chart and The phase information on the Smith chart is used as a reference to adjust the coupling cavity and power coupler.

[0034] Specifically, by connecting a short acceleration cavity chain to the rear end of the power coupler and the coupling cavity, and adjusting the dimensions of the coupling cavity and the power coupler according to the resonant frequency of the coupling cavity measured when the piston is at different positions in the cavity (i.e., when the piston is at the center of the coupling cavity and the center of the acceleration cavity adjacent to the coupling cavity), and the phase information of the operating frequency of the coupling cavity in different operating modes on the Smith chart, the matching can be completed.

[0035] It is understandable that the coupling cavity is connected to the power coupler, therefore, the coupling cavity and the power coupler can be matched by adjusting the size of the coupling cavity.

[0036] like Figure 4 As shown, the host computer control interface provided by the present invention may include a parameter setting section, a status display section, a motor control section, a data management section, etc.

[0037] In the parameter setting section, you can set the measured humidity, measured temperature, and vacuum chamber frequency. After accurately measuring the center position of the test chamber, the chamber number and motor position information are imported, and the system makes the motor run accurately to the imported position.

[0038] The status display shows the motor's motion status, the coordinates reached during this run, the coordinates at the end of the previous run, and the distance traveled in real time. The interface also updates the motor's position coordinates synchronously as it moves.

[0039] The motor control section can perform operations such as motor homing, coordinate zeroing, start control, and emergency stop. The system establishes a zero-point reference, at which point the motor will run to the position of the infrared sensor. If an error occurs during system operation, the coordinates can be zeroed and readjusted. In case of unexpected motor operation, an emergency stop can be performed to ensure safety.

[0040] The data management section reads and calculates data such as the current cavity number, the corresponding phase and phase difference of the current cavity number, and the cumulative phase difference in real time. At the same time, the system can display the phase shift between phases and the cumulative phase shift curve on the main interface to realize real-time visualization of the measurement results, and can store them after the measurement is completed.

[0041] During operation, the system can synchronously execute motor movement, signal acquisition, and calculation processes after basic settings, achieving automated measurement. If the motor position exceeds the limit or communication is interrupted, the system can automatically stop operation, or the operator can manually perform an emergency stop, ensuring safe and reliable system operation.

[0042] This invention provides an automatic tuning method for a traveling-wave accelerator tube, applicable to an automatic tuning and adjustment system for a traveling-wave accelerator tube as described in any of the above embodiments, such as... Figure 5As shown, it includes: S1, the host computer sequentially uses each acceleration cavity of the traveling wave accelerator tube as the target acceleration cavity. After tuning the target acceleration cavity through the tuning and adjustment module, it sends a control command to the motor control box. After receiving the control command, the motor control box controls the first servo motor to drive the precision displacement platform to the coordinate zero point position, and then drives the first servo motor to run, thereby driving the piston to reach the center position of the target acceleration cavity. S2, the temperature and humidity sensor measures the ambient temperature and humidity and forwards the data to the host computer; the power coupler injects energy into the traveling wave accelerator tube, and the network analyzer reads the resonant frequency and phase of the target accelerator cavity and forwards the data to the host computer; S3, the host computer corrects the resonant frequency of the target accelerating cavity according to the ambient temperature and humidity, calculates the inter-cavity phase shift and cumulative phase difference according to the phase of the target accelerating cavity, and obtains the tuning result. If the tuning result meets the standard, the process ends; otherwise, it returns to S1 until the tuning result meets the standard.

[0043] Specifically, based on the automatic tuning and adjustment system for traveling wave accelerator tubes described in any of the above embodiments, the tuning tests for the entire traveling wave accelerator tube and individual cavities are performed as follows: During the measurement process, to determine the specific position the motor needs to reach, a one-dimensional coordinate system is established with the motor's zero-return position (i.e., the infrared sensor position) as the origin, based on the direction of motion. Considering the sensitivity of the cavity number during tuning, a correspondence is established between the cavity number and the coordinates, and each cavity is calibrated. Since the piston needs to be in the middle of the cavity (i.e., the exact center of the cavity) during tuning, the coordinates of the center position of the cavity are used as the motor's stopping position, and this is read into the host computer control system using a txt file. The motor drives the piston to move, and according to the pre-set position, the motor stops in the middle of each cavity. Then, the network analyzer reads the resonant frequency and the phase at the corrected frequency at this time and returns the results to the host computer.

[0044] To consider the overall performance of the cavity, the host computer processes the data from the network analyzer to obtain the resonant frequency, phase difference, and cumulative phase difference, and then visualizes them to facilitate the judgment of the tuning results. To ensure intuitive data display during the tuning process, the inter-cavity phase shift and cumulative value are displayed on the same screen in real time. After the measurement is completed, the measurement results can be saved in either graphical or data table format.

[0045] To avoid data redundancy, the data storage function can be disabled during tuning, with only the real-time display module enabled. After tuning is complete, the system will re-enable the data storage function and save the valid measurement data in cavity number order.

[0046] To improve data processing efficiency, newly acquired data is inserted into the first row in chronological order for easy retrieval and calculation. This function helps track the phase shift trend of the cavity during tuning and provides a basis for subsequent corrections.

[0047] The experimental testing platform is stable in structure and easy to operate. During testing, a microwave signal is injected into the coupler, and a short-circuit piston is used at the other end to create reflection. Frequency scanning is performed using a network analyzer to obtain the resonant characteristics and phase information of each cavity. The data is then transmitted to a host computer via a network cable for processing and display.

[0048] This invention provides an automatic tuning method for traveling wave accelerator tubes, applied to an automatic tuning and tuning system for traveling wave accelerator tubes as described in any of the above embodiments, comprising: S1, after the host computer completes the tuning and adjustment of the coupling cavity and the power coupler through the tuning and adjustment module, it takes the center position of the coupling cavity and the center position of the adjacent acceleration cavity as the target position of the piston and sends a control command to the motor control box. After receiving the control command, the motor control box controls the first servo motor to drive the precision displacement platform to the coordinate zero point position, and then drives the first servo motor to run, thereby driving the piston to reach the target position. S2, the temperature and humidity sensor measures the ambient temperature and humidity and forwards the data to the host computer; the power coupler injects energy into the traveling wave accelerator tube; the network analyzer reads the resonant frequency of the coupling cavity and the phase information of the coupling cavity's operating frequency in different operating modes on the Smith chart and forwards it to the host computer. S3, the host computer corrects the resonant frequency of the coupling cavity according to the ambient temperature and humidity, receives the phase information of the operating frequency of the coupling cavity in different working modes on the Smith chart, and obtains the tuning result. If the tuning result meets the standard, the process ends; otherwise, it returns to S1 until the tuning result meets the standard.

[0049] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An automatic tuning and adjustment system for traveling wave accelerator tubes, characterized in that, include: The motor and motion components include a first servo motor, a first screw, a carbon fiber rod, and a first precision displacement platform; the lower end of the precision displacement platform is connected to the screw and positioned above the screw, and the upper end is connected to one end of the carbon fiber rod, with a piston mounted on the other end of the carbon fiber rod; the output end of the first servo motor is coaxially connected to the first screw to drive the first screw to rotate, thereby driving the carbon fiber rod connected to the first precision displacement platform to produce a stepping movement, so that the piston located at the other end of the carbon fiber rod enters the target acceleration cavity in the traveling wave accelerator tube from one end of the traveling wave accelerator tube; The motor control box is used to control the operation of the first servo motor according to the control instructions from the host computer. Temperature and humidity sensors are used to measure ambient temperature and humidity and transmit the data to a host computer. The tuning and matching module is used to tune the target accelerating cavity or match the coupling cavity and power coupler. A network analyzer, connected to a power coupler located at the other end of the traveling wave accelerator tube, is used to read relevant information to a host computer after the piston reaches the center position of the target accelerator cavity and the power coupler injects energy into the traveling wave accelerator tube. During tuning, the relevant information includes the resonant frequency and phase of the target accelerator cavity; during adjustment, the relevant information includes the resonant frequency of the coupling cavity and the phase information of the operating frequency of the coupling cavity in different operating modes on the Smith chart. The host computer sequentially selects each accelerating cavity of the traveling wave accelerator tube as the target accelerating cavity. After tuning the target accelerating cavity through the tuning and matching module, the first servo motor is controlled by the motor control box to drive the piston to the center position of the target accelerating cavity. The resonant frequency of the target accelerating cavity is corrected according to the ambient temperature and humidity. The phase shift between adjacent accelerating cavities and the cumulative phase difference between all adjacent accelerating cavities are calculated according to the phase of the target accelerating cavity to obtain the tuning result. Alternatively, after the tuning and tuning module completes the tuning of the coupling cavity and the power coupler, the center position of the coupling cavity and the center position of the adjacent acceleration cavity are respectively used as the target position of the piston. The first servo motor is controlled by the motor control box to drive the piston to the target position. The resonant frequency of the coupling cavity is corrected according to the ambient temperature and humidity. The phase information of the operating frequency of the coupling cavity in different working modes on the Smith chart is received to obtain the tuning result.

2. The system as described in claim 1, characterized in that, The tuning and adjustment module includes a first and a second ejector pin, a second precision displacement platform, a second screw, a second, a third, and a fourth servo motor, and their respective motor controllers; The output end of the second servo motor is coaxially connected to the second screw, which is used to drive the second screw to rotate, thereby driving the first and second ejector pins connected to the second precision displacement platform to move in a stepping manner, so that the first and second ejector pins reach the target acceleration cavity or coupling cavity. The third and fourth servo motors are respectively used to drive the first and second ejector pins to squeeze the target acceleration cavity or coupling cavity from different directions, thereby completing the tuning of the target acceleration cavity or the adjustment of the coupling cavity and the power coupler. The host computer controls the second servo motor through the controller of the second servo motor to drive the first and second ejector pins to the target acceleration cavity or coupling cavity. The controllers of the third and fourth servo motors respectively drive the first and second ejector pins to squeeze the target acceleration cavity or coupling cavity from different directions to adjust the size of the target acceleration cavity or coupling cavity, thereby completing the tuning of the target acceleration cavity or the adjustment of the coupling cavity and power coupler.

3. The system as described in claim 1, characterized in that, The measured resonant frequency of the target accelerating cavity or coupling cavity The resonant frequency of the modified target accelerating cavity or coupling cavity The following relationship must be satisfied: ； in, , , , , To test the relative permittivity of air under the test environment, This refers to the frequency change caused by the ambient temperature differing from the cavity's operating temperature. and They are respectively in T At that time, the partial pressure occupied by dry gas and water vapor, T For ambient temperature, H For ambient humidity, This represents the saturated vapor pressure corresponding to the ambient humidity. It is the rate of change of the resonant frequency of the accelerating structure with the temperature of the cavity. It is the difference between the working temperature of the cavity and the ambient temperature.

4. The system as described in claim 1, characterized in that, The motor control box includes: The zero-return module is used to control the first servo motor to move the precision displacement platform to the coordinate zero point position after receiving the control command sent by the host computer. The first servo motor drive board is used to convert the control commands sent by the host computer into pulse signals to drive the first servo motor to run, thereby driving the piston to reach the center position or target position of the target acceleration chamber. The encoder signal processing module is used to compare the current running position of the first servo motor with the specified position, and to compensate for the deviation through negative feedback, so as to perform closed-loop control of the first servo motor.

5. The system as described in claim 4, characterized in that, The motor control box has an integrated structure.

6. The system as described in claim 1, characterized in that, The screw, carbon fiber rod, and precision displacement platform are arranged coaxially along the central axis of the traveling wave accelerator tube.

7. The system as described in claim 1, characterized in that, The host computer visualizes the tuning or adjustment results in the form of graphs or data tables.

8. An automatic tuning method for a traveling-wave accelerator tube, applied to the automatic tuning and adjustment system for a traveling-wave accelerator tube as described in any one of claims 1-7, characterized in that, include: S1, the host computer sequentially uses each acceleration cavity of the traveling wave accelerator tube as the target acceleration cavity. After tuning the target acceleration cavity through the tuning and adjustment module, it sends a control command to the motor control box. After receiving the control command, the motor control box controls the first servo motor to drive the precision displacement platform to the coordinate zero point position, and then drives the first servo motor to run, thereby driving the piston to reach the center position of the target acceleration cavity. S2, the temperature and humidity sensor measures the ambient temperature and humidity and forwards the data to the host computer; the power coupler injects energy into the traveling wave accelerator tube, and the network analyzer reads the resonant frequency and phase of the target accelerator cavity and forwards the data to the host computer; S3, the host computer corrects the resonant frequency of the target acceleration cavity according to the ambient temperature and humidity, calculates the inter-cavity phase shift and cumulative phase difference according to the phase of the target acceleration cavity, and obtains the tuning result. If the tuning result meets the standard, the process ends. Otherwise, return to S1 until the tuning result meets the requirements.

9. An automatic tuning method for a traveling wave accelerator tube, applied to the automatic tuning and tuning system for a traveling wave accelerator tube as described in any one of claims 1-7, characterized in that, include: S1, after the host computer completes the tuning and adjustment of the coupling cavity and the power coupler through the tuning and adjustment module, it takes the center position of the coupling cavity and the center position of the adjacent acceleration cavity as the target position of the piston and sends a control command to the motor control box. After receiving the control command, the motor control box controls the first servo motor to drive the precision displacement platform to the coordinate zero point position, and then drives the first servo motor to run, thereby driving the piston to reach the target position. S2, the temperature and humidity sensor measures the ambient temperature and humidity and forwards the data to the host computer; the power coupler injects energy into the traveling wave accelerator tube; the network analyzer reads the resonant frequency of the coupling cavity and the phase information of the coupling cavity's operating frequency in different operating modes on the Smith chart and forwards it to the host computer. S3, the host computer corrects the resonant frequency of the coupling cavity according to the ambient temperature and humidity, receives the phase information of the operating frequency of the coupling cavity in different working modes on the Smith chart, and obtains the tuning result. If the tuning result meets the standard, the process ends. Otherwise, return to S1 until the allocation result meets the requirements.

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