A negative feedback automatic energy control device and method for a low-energy linear accelerator

Abstract

This invention relates to a negative feedback automatic energy control device and method suitable for low-energy linear accelerators. The device includes a first beam diagnostic chamber and a second beam diagnostic chamber. The first beam diagnostic chamber includes a first Faraday cylinder, and the second beam diagnostic chamber includes a second Faraday cylinder. A mass spectrometer diode is positioned between the first and second beam diagnostic chambers. The beam enters the mass spectrometer diode after passing through the first beam diagnostic chamber, changes direction within the mass spectrometer diode, and then enters the second beam diagnostic chamber. A first beam intensity is obtained by measuring the first Faraday cylinder in the first beam diagnostic chamber, and a second beam intensity is obtained by monitoring the second Faraday cylinder in the second beam diagnostic chamber. The amplitude and phase parameters of the high-frequency cavity are dynamically adjusted using a negative feedback control algorithm until the second beam intensity is less than a first predetermined proportion of the first beam intensity. This device can automatically control beam divergence, automatically detect beam divergence information, and provide real-time feedback to the control system for divergence stabilization.

Description

Technical Field

[0001] This invention relates to the field of accelerator technology, and in particular to an automatic beam energy control device and method for low-energy linear accelerators, especially to a negative feedback control technology based on multi-system cooperation for optimizing beam energy dispersion, energy deviation and transmission efficiency. Background Technology

[0002] In recent years, low-energy, high-current heavy-ion linear accelerators have played a crucial role in nuclear physics, nuclear energy materials research, and high-energy physics experiments. Ion beam energy manipulation technology is particularly vital in nuclear astrophysics and irradiation experiments.

[0003] Existing beam energy control devices primarily rely on manual adjustment, using manual manipulation of the accelerator's high-frequency cavity parameters and the operating point of the beamline magnets to switch and optimize beam energy. However, manual control has the following significant drawbacks:

[0004] 1. Time-consuming and labor-intensive: In multi-point energy control experiments, researchers need to frequently adjust the beamline components, such as the high-frequency cavity voltage, phase, and the magnetic field of the diode magnet. This process is time-consuming and requires highly skilled operators.

[0005] 2. Insufficient precision and efficiency: Manual control makes it difficult to guarantee high-precision energy regulation and rapid switching, and beam energy dissipation and transmission efficiency may be limited;

[0006] 3. Low degree of automation: Traditional manual control methods are difficult to meet the needs of complex experiments, such as continuous variable energy or multi-energy point irradiation experiments.

[0007] For example, in the study of low-energy fusion reactions in nuclear astrophysics, it is necessary to rapidly switch the ion beam energy to different energy points to fill the product curves in the Gamow energy region. Simultaneously, the experiment requires beam energy dispersion of less than 0.3% and high transmission efficiency to reduce beam loss. However, current manual adjustment methods are time-consuming, often requiring half an hour of manual optimization for each energy point to meet the requirements. If the experimental terminal requires frequent energy adjustments, manual adjustment becomes inadequate, not only wasting manpower but also making it difficult to guarantee the accuracy of manual adjustments under high-intensity work. Therefore, there is an urgent need for a technology that can achieve automated and high-precision energy adjustment and control. Summary of the Invention

[0008] To address the aforementioned problems, the purpose of this invention is to provide a negative feedback automatic energy regulation device and method for low-energy linear accelerators.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] A negative feedback automatic energy control device suitable for low-energy linear accelerators includes: a first beam diagnostic chamber and a second beam diagnostic chamber. The first beam diagnostic chamber includes a first Faraday cylinder, and the second beam diagnostic chamber includes a second Faraday cylinder. A mass spectrometer diode is disposed between the first beam diagnostic chamber and the second beam diagnostic chamber. After passing through the first beam diagnostic chamber, the beam enters the mass spectrometer diode, where it changes direction. After passing through the mass spectrometer diode, the beam enters the second beam diagnostic chamber. A first beam intensity is obtained by measuring the first Faraday cylinder in the first beam diagnostic chamber, and a second beam intensity is obtained by monitoring the second Faraday cylinder in the second beam diagnostic chamber. The amplitude and phase parameters of the high-frequency cavity are dynamically adjusted through a negative feedback control algorithm until the second beam intensity is less than a first preset ratio of the first beam intensity, where the first preset ratio is 1%.

[0011] Preferably, a quarter-wavelength beam gatherer is provided before the first beam chamber to suppress energy dissipation growth.

[0012] Preferably, a first slit is provided in the first beam examination chamber, and a second slit is provided in the second beam examination chamber. The first slit and the second slit are adjusted to a first opening (preferably ±1mm). When the beam flows into the second Faraday tube of the second beam examination chamber, the beam intensity is recorded. The output power of the quarter-wavelength beam gatherer is adjusted to a set value (preferably 500 watts). The phase is scanned from 0 degrees to 360 degrees to find the phase value corresponding to the maximum current value of the second Faraday tube in the second beam examination chamber. Then, the output power of the quarter-wavelength beam gatherer is finely adjusted up and down (preferably in an adjustment step of about 50 watts each time). The high-frequency parameters of the quarter-wavelength beam gatherer are found by reading back the current of the second Faraday tube in the second beam examination chamber.

[0013] Preferably, a first beam position detector is provided at the entrance of the first beam examination room, and a second beam position detector is provided at the exit of the first beam examination room. The distance between the first beam position detector and the second beam position detector is L. By collecting the flight time t of the beam from entering the first beam position detector to leaving the second beam position detector, the flight speed v = L / t of the beam is calculated, so as to convert the speed into the energy of the beam using the kinetic energy formula.

[0014] Preferably, the second Faraday tube in the second beam diagnostic chamber is a blocking Faraday tube, and the second beam diagnostic chamber also includes a two-dimensional dual-wire detector for measuring the deflected beam intensity and measuring the beam profile to calculate the energy deviation and beam energy dispersion.

[0015] A negative feedback automatic energy control method suitable for low-energy linear accelerators is provided, which measures the first Faraday tube in the first beam diagnostic chamber to obtain the beam intensity, and simultaneously monitors the signal of the second Faraday tube in the second beam diagnostic chamber in real time to obtain the initial parameters of the high-frequency cavity.

[0016] Preferably, the amplitude increases by a predetermined value (preferably 0.01V) and the phase is scanned 360 degrees, and the high-frequency parameter modulation is automatically adjusted and scanned according to the feedback signal of the first Faraday cylinder.

[0017] Preferably, when the second Faraday tube reads back the beam signal, it starts recording data and continues to step-modulate the high-frequency parameters until the beam signal read after parameter adjustment is less than a first set ratio of the beam intensity, and then stops, obtaining the high-frequency cavity parameters corresponding to the maximum signal value of the second Faraday tube, so as to end the energy regulation.

[0018] Preferably, when the fluctuation of the beam intensity is greater than a second set ratio (preferably 10%) of the maximum value of the beam signal, the current value of the mass spectrometer diode magnet is first finely adjusted by increasing and then decreasing by 1 ampere based on the original parameter, and the change in beam intensity is compared; if the beam intensity recovers to the initial maximum value of the beam signal, it indicates that the beam energy has changed, and at this time the energy calibration step will be performed.

[0019] Preferably, the slit opening is first kept at ±1mm, and then the horizontal envelope of the bundle is scanned using a wire scanning detector. The energy dissipation information of the beam is calculated by the correlation formula between the envelope and the system dispersion function, so as to perform energy dissipation monitoring.

[0020] The present invention has the following advantages due to the adoption of the above technical solutions:

[0021] 1. Improve experimental efficiency: Through automated control, manual operation time is significantly reduced, thereby improving experimental efficiency;

[0022] 2. Precise energy control: Automatically controls beam energy, automatically detects energy accuracy, and provides real-time feedback to the control system for fine-tuning of energy;

[0023] 3. Optimize beam performance: reduce beam energy dissipation, improve transmission efficiency, and meet the requirements of high-precision experiments;

[0024] 4. Reduce labor costs: Reduce the consumption of human and material resources through program control and automated operation. Attached Figure Description

[0025] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. In the drawings:

[0026] Figure 1 This is a schematic diagram of the structure of an automatic energy regulation device according to an embodiment of this application;

[0027] Figure 2 This is a schematic flowchart of an energy regulation method according to an embodiment of this application; and

[0028] Figure 3 This is a schematic flowchart of an energy dissipation control method according to an embodiment of this application.

[0029] The markings in the attached diagram are as follows:

[0030] 1. Increasing / reducing energy linear accelerator (IDL); 2. Quarter-wavelength rebuncher (QWR-Rebuncher); 3. First beam position detector (BPM-1); 4. First slit (S1); 5. First Faraday tube (FC1); 6. First beam chamber (pre-deflection beam chamber D1); 7. Second beam position detector (BPM-2); 8. Mass spectrometer diode magnet (MSD); 9. Second slit (S2); 10. Wire scanning detector (WS); 11. Second Faraday tube (FC2); 12. Second beam chamber (post-deflection beam chamber D2). Detailed Implementation

[0031] Exemplary embodiments of this application will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of this application are shown in the drawings, it should be understood that this application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of this application and to fully convey the scope of this application to those skilled in the art. In the following, although examples of this disclosure will be described in detail with reference to the accompanying drawings, it should be noted that the examples are not limited thereto.

[0032] The following detailed embodiments are provided to aid the reader in gaining a comprehensive understanding of the methods, apparatus, and / or systems described herein. However, various changes, modifications, and equivalents to the methods, apparatus, and / or systems described herein will become apparent upon understanding this disclosure. For example, the order of operations described herein is merely illustrative and is not limited to the order set forth herein, except for operations that must occur in a specific order, as will become apparent upon understanding this disclosure. Furthermore, for clarity and brevity, descriptions of features well-known in the art may be omitted.

[0033] The features described herein may be implemented in different forms and should not be construed as being limited to the examples described herein. Rather, the examples described herein are provided merely to illustrate some of the many possible ways in which the methods, apparatuses, and / or systems described herein will become apparent upon understanding this disclosure.

[0034] Throughout this specification, when an element is described as being "on," "connected to," or "attached to" another element, the element may be directly "on," directly "connected to," or directly "attached to" the other element, or there may be one or more other elements between the element and the other element. Conversely, when an element is described as being "directly on," "directly connected to," or "directly attached to" another element, there are no other elements between the element and the other element.

[0035] As used herein, the term “and / or” includes any one of the associated listed items and any combination of any two or more items; similarly, “at least one” includes any one of the associated listed items and any combination of any two or more items.

[0036] Although terms such as “first,” “second,” and “third” may be used herein to describe various components, parts, regions, layers, or sections, these components, parts, regions, layers, or sections are not limited by these terms. Rather, these terms are used only to distinguish one component, part, region, layer, or section from another. Therefore, without departing from the teachings of the examples described herein, the first component, first part, first region, first layer, or first section mentioned in these examples may also be referred to as a second component, second part, second region, second layer, or second section.

[0037] Spatial relative terms such as “above,” “above,” “below,” and “below” may be used herein for descriptive convenience to describe the relationship of one element relative to another, as shown in the accompanying drawings. In addition to covering the orientation depicted in the drawings, these spatial relative terms are intended to also cover different orientations of the device in use or operation. For example, if the device in the drawings is flipped, an element described as being “above” or “above” another element would be located “below” or “below” that other element. Thus, depending on the spatial orientation of the device, the term “above” covers both orientations of “above” and “below”. The device may also be oriented in other ways (e.g., rotated 90 degrees or in other orientations), and the spatial relative terms used herein should be interpreted accordingly.

[0038] The terminology used herein is for the purpose of describing various examples only and is not intended to limit this disclosure. Unless the context clearly indicates otherwise, the terms “a,” “an,” and “the” are intended to include the plural form as well. The terms “comprising,” “including,” and “having” indicate the presence of the stated features, numbers, operations, components, elements, and / or combinations thereof, but do not preclude the presence or addition of one or more other features, numbers, operations, components, elements, and / or combinations thereof.

[0039] Variations in the shapes shown in the figures may occur due to manufacturing techniques and / or tolerances. Therefore, the examples described herein are not limited to the specific shapes shown in the figures, but include shape variations that may occur during manufacturing.

[0040] It should be noted that in this document, the word “may” is used relative to “example”, such as regarding what an example may include or implement, meaning that there exists at least one example that includes or implements such a feature, but not all examples are limited to this.

[0041] The features of the examples described herein can be combined in various ways that will become apparent upon understanding this disclosure. Furthermore, although the examples described herein have multiple configurations, other configurations that will become apparent upon understanding this disclosure are also possible.

[0042] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a negative feedback automatic energy control device and method suitable for low-energy linear accelerators. This method achieves automated beam energy adjustment, optimization, and detection through multi-system collaboration, meeting the needs of complex experiments. This invention aims to achieve the following functions:

[0043] Automatic energy regulation: Based on negative feedback control technology, it realizes automatic switching of beam energy, while optimizing beam energy dissipation and transmission efficiency;

[0044] High precision and high efficiency: Through real-time monitoring and feedback control, the beam energy dissipation is ensured to be less than 0.3% and the transmission efficiency is greater than 95%;

[0045] Adaptable to complex experimental needs: Supports continuous multi-point automatic energy regulation (e.g., from 0.3 MeV / u to 1.0 MeV / u), meeting the wide range of needs of nuclear astrophysics and nuclear energy materials experiments.

[0046] A negative feedback automatic energy control method for low-energy linear accelerators according to an embodiment of this application includes:

[0047] Energy regulation

[0048] As is well known, charged ion beams undergo a series of physical processes such as deflection, focusing, and defocusing under the influence of a uniform magnetic field. The extent of these processes depends on the magnetic stiffness of the ions, which in turn is determined by the type and energy of the ions. Therefore, if ions continue to be transmitted during energy conversion, losses will inevitably occur, causing beam mismatch in the trajectory. To protect all equipment and cavities along the beam transmission line, the continuous wave beam must be switched to a pulsed beam before energy conversion to minimize equipment damage caused by beam mismatch. The commonly used pulsed beam parameters are a frequency of 1 Hz and a duty cycle of 0.01%.

[0049] The magnetic stiffness at the target ion energy was calculated and then converted into the current value of the mass spectrometer dipole magnet (MSD) 8. First, the beam intensity I1 measured by the Faraday tube (FC1) 5 in the pre-deflection beam diagnostic chamber (D1) 6 was obtained. Initial parameters a0 and p0 of the high-frequency cavity (increased / decreased energy linear accelerator IDL) were set. Simultaneously, the monitoring system monitored the beam signal I2 of the blocking Faraday tube (FC2) 11 in the post-deflection beam diagnostic chamber (D2) 12 in real time. The high-frequency control system automatically adjusted and scanned the parameters of the high-frequency cavity by scanning the phase 360 ​​degrees for every 0.01V increase in amplitude. It also automatically determined whether to continue high-frequency parameter modulation based on the feedback signal from the Faraday tube. Data recording began when the Faraday tube read back the beam signal, and the high-frequency parameters were continuously modulated stepwise until the beam signal I2 read after parameter adjustment was less than 1% of the beam intensity I1. The high-frequency cavity parameters a1 and p1 corresponding to the maximum value of the beam signal I2 were then obtained, and the entire energy modulation process ended.

[0050] Energy monitoring

[0051] There are two ways to monitor energy:

[0052] One method involves calculating energy using the Time-of-Flight (TOF) method, which utilizes the beam position detector located in the pre-deflection beam diagnostic chamber (D1) 6. The beam position detector consists of two parts: a first beam position detector (BPM-1) 3 and a second beam position detector (BPM-2) 7, located at the entrance and exit of the pre-deflection beam diagnostic chamber (D1) 6, respectively, separated by a distance L. By collecting the flight time t of the beam from entering the first beam position detector (BPM-1) 3 to exiting the second beam position detector (BPM-2) 7, the beam's velocity v = L / t can be calculated. Finally, the velocity can be converted into beam energy using the kinetic energy formula.

[0053] Secondly, the beam intensity is continuously monitored via a second Faraday tube (FC2) 11 located in the pre-deflection beam diagnostic chamber (D2) 12. When the fluctuation in beam intensity exceeds 10% of the maximum value of the beam signal I2, the current value of the mass spectrometer diode (MSD) 8 is first finely adjusted, i.e., increased and then decreased by 1 ampere based on the original parameter, and the change in beam intensity is compared. If the beam intensity can be restored to the initial maximum value of the beam signal I2, it indicates that the beam energy has changed, and an energy calibration step will be performed at this time.

[0054] Energy calibration

[0055] Deviations in beam energy during operation may be due to a series of reasons such as detuning of the high-frequency cavity, vacuum fluctuations, and water flow fluctuations. In such cases, automatic energy calibration is required. First, compare the cavity's readback parameters with the set parameters a1 and p1 to see if they match. Then, adjust the high-frequency parameters to bring the energy back to normal.

[0056] Energy dissipation regulation

[0057] Due to the characteristics of radio frequency accelerators, heavy ion beams exhibit significant energy divergence after energy modulation. This divergence growth can be effectively suppressed using a quarter-wavelength rebuncher (QWR-Rebuncher) 2. Because of this divergence, the beam's lateral dimension increases under the influence of the diode field. If this lateral dimension exceeds the tube limit, losses occur. Therefore, energy divergence control is based on this method. First, the first slit (S1) and second slit (S2) in the pre-deflection beam chamber (D1) 6 and the post-deflection beam chamber (D2) 12 are adjusted to an opening of ±1 mm. Then, the beam is introduced into the second Faraday tube (FC2) 11 of the post-deflection beam chamber (D2) 12, and the beam intensity is recorded. Subsequently, the output power of the focuser (QWR-Rebuncher) 2 was adjusted to approximately 500 watts, and the phase was scanned from 0 degrees to 360 degrees to find the phase value corresponding to the maximum current value of the second Faraday cylinder (FC2) 11. Then, the output power of the focuser (QWR-Rebuncher) 2 was finely adjusted up and down, with each adjustment step being approximately 50 watts. Based on the current readback of the second Faraday cylinder (FC2) 11, the optimal high-frequency parameters of the focuser (QWR-Rebuncher) 2 were found.

[0058] Energy dissipation monitoring

[0059] The monitoring of heavy ion beam energy dissipation is achieved through a combination of a slit and a wire scanning detector. First, the opening of the first slit 4 is kept at ±1 mm. Then, the horizontal envelope of the beam is scanned using the wire scanning detector 10, and the energy dissipation information of the beam can be calculated.

[0060] A negative feedback automatic energy regulation device for low-energy linear accelerators according to an embodiment of this application includes:

[0061] Pre-deflection beam diagnostic chamber: Its main components are a blocking Faraday tube, a double slit, and a beam position detector. Located in front of the diode magnet, it is used to detect the beam intensity, lateral profile, and beam energy before deflection by the diode magnet.

[0062] Mass spectrometer dipole magnet: The main components are a dipole magnet and an embedded Hall probe system. It is used for deflecting the beam in orbit, reading back the magnetic field, and filtering the beam energy.

[0063] High-frequency cavity: The main components are a drift tube-type linear accelerator with increasing and decreasing energy and a quarter-wavelength beam mixer. These are used to switch beam energy and suppress beam energy dispersion.

[0064] Post-deflection beam diagnostic chamber: The main components are a blocking Faraday cage and a two-dimensional wire scanning detector. It is used to measure the intensity of the deflected beam and to measure the beam profile to calculate energy deviation and beam energy dispersion.

[0065] Negative feedback control unit: The main components are the control system and feedback algorithm. By integrating the above systems, real-time energy regulation and optimization are achieved through multi-system collaboration.

[0066] Figure 1 This is a schematic diagram of the structure of an automatic energy regulation device according to an embodiment of this application.

[0067] like Figure 1 As shown, the deflection front beam diagnostic chamber, namely the first beam diagnostic chamber (D1) 6, includes the first Faraday tube (FC1) 5, the first slit (S1) 4, and beam position detectors (BPM-1 and BPM-2).

[0068] The first beam chamber (D1) 6 is located in front of the mass spectrometer diode (MSD) 8 and is used to detect the beam intensity, cross-sectional area and beam energy before being deflected by the mass spectrometer diode (MSD) 8.

[0069] The Mass Spectrometer Diode Magnet (MSD) 8 includes a dipole magnet and an embedded Hall probe system for deflecting the beam in orbit, reading back the magnetic field, and screening the beam energy.

[0070] The high-frequency cavity includes an add-drop linear accelerator (IDL) 1 and a quarter-wavelength rebuncher (QWR-Rebuncher) 2, which are used to switch beam energy and suppress beam energy dispersion.

[0071] The deflection beam chamber, also known as the second beam chamber (D2) 12, includes a second Faraday tube (FC2) 11, a second slit (S2) 9, and a wire scanning detector (WS) 10, used to measure the intensity of the deflected beam and to measure the beam profile in order to calculate the energy deviation and beam energy dispersion.

[0072] The negative feedback control unit includes a control system and a feedback algorithm, which achieves real-time energy regulation and optimization through multi-system cooperation.

[0073] The advantages of the automatic energy regulation device according to the embodiments of this application include:

[0074] Automation, through program control, enables automatic switching of ion beam energy, reducing human intervention;

[0075] High-precision, fast and stable automatic adjustment of beam energy ensures energy accuracy while maintaining beam energy divergence within the optimal range;

[0076] The high-efficiency, real-time feedback mechanism ensures that the beam transmission efficiency is higher than 95% before and after deflection.

[0077] like Figure 2 This is a schematic flowchart of an energy regulation method according to an embodiment of this application, such as... Figure 2 As shown, the energy regulation method process includes:

[0078] S1: Set beam energy

[0079] S2: Set the beam duty cycle to 0.01%.

[0080] S3: Set initial cavity parameters a0, p0

[0081] S4: Calculate the beam magnetic stiffness

[0082] S5: Convert magnet current

[0083] S6: Bundle magnet modulation

[0084] S7: Measure the initial beam intensity I1

[0085] S8: Cavity amplitude +0.01V

[0086] S9: Cavity phase 0-360 degree scan

[0087] S10: Record the FC2 beam current intensity I2

[0088] S11: Locating the peak FC2 beam intensity

[0089] S12: Record and set the high-frequency parameters a1 and p1 at the peak value.

[0090] Figure 3 This is a schematic flowchart of the energy dissipation control method according to an embodiment of this application, as shown below. Figure 3 As shown, the energy dissipation control method includes the following steps:

[0091] S13: Adjust slits S1 and S2 to ±1mm

[0092] S14: Record the beam intensity of FC2

[0093] S15: Set initial clustering parameters to 500W and 0 degrees.

[0094] S16: Cavity phase 0-360 degree scan

[0095] S17: Record the change of FC2 current intensity readback value with cavity phase.

[0096] S18: Find the cavity phase P1 that maximizes the FC2 current intensity.

[0097] S19: Keep P1, fine-tune the cavity power up or down in 50W increments.

[0098] S20: Find and set the optimal parameters for the clusterer.

[0099] While specific examples have been shown and described above, it will be apparent upon understanding this disclosure that various changes in form and detail may be made to these examples without departing from the spirit and scope of the claims and their equivalents. The examples described herein are to be understood in a descriptive sense only and not for limiting purposes. The description of features or aspects in each example should be considered applicable to similar features or aspects in other examples. Suitable results may still be achieved if the described techniques are performed in a different order, and / or if components in the described system, architecture, device, or circuit are combined in different ways and / or replaced or supplemented by other components or their equivalents. Therefore, the scope of this disclosure is not limited by the specific embodiments but by the claims and their equivalents, and all variations within the scope of the claims and their equivalents should be understood to be included in this disclosure.

[0100] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A negative feedback automatic energy regulation device suitable for low-energy linear accelerators, characterized in that, The system includes a first beam examination chamber and a second beam examination chamber. The first beam examination chamber includes a first Faraday tube, and the second beam examination chamber includes a second Faraday tube. A mass spectrometer diode magnet is disposed between the first beam examination chamber and the second beam examination chamber. After passing through the first beam examination chamber, the beam enters the mass spectrometer diode magnet, where it changes direction. After passing through the mass spectrometer diode magnet, the beam enters the second beam examination chamber. A first beam intensity is obtained by measuring the first Faraday tube in the first beam examination chamber, and a second beam intensity is obtained by monitoring the second Faraday tube in the second beam examination chamber. The amplitude and phase parameters of the high-frequency cavity are dynamically adjusted through a negative feedback control algorithm until the second beam intensity is less than a first set ratio of the first beam intensity. A quarter-wavelength beamsettler is placed before the first beam chamber to suppress energy dissipation growth; A first slit is provided in the first beam examination chamber, and a second slit is provided in the second beam examination chamber. The first slit and the second slit are adjusted to a first opening. When the beam flows into the second Faraday tube of the second beam examination chamber, the beam intensity is recorded. The output power of the quarter-wavelength beam gatherer is adjusted to a set value. The phase is scanned from 0 degrees to 360 degrees to find the phase value corresponding to the maximum current value of the second Faraday tube in the second beam examination chamber. Then, the output power of the quarter-wavelength beam gatherer is finely adjusted up and down. The high-frequency parameters of the quarter-wavelength beam gatherer are found by reading back the current of the second Faraday tube in the second beam examination chamber. A first beam position detector is installed at the entrance of the first beam examination room, and a second beam position detector is installed at the exit of the first beam examination room. The distance between the first beam position detector and the second beam position detector is L. By collecting the flight time t of the beam from entering the first beam position detector to leaving the second beam position detector, the flight speed v=L / t of the beam is calculated, so as to convert the speed into the energy of the beam using the kinetic energy formula.

2. The negative feedback automatic energy regulation device for low-energy linear accelerators according to claim 1, characterized in that, The second Faraday tube in the second beam examination chamber is a blocking Faraday tube. The second beam examination chamber also includes a two-dimensional dual-wire detector for measuring the deflected beam intensity and measuring the beam profile to calculate the energy deviation and beam energy dispersion.

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