Control System of High-Intensity Proton Accelerator for Boron Neutron Capture Therapy System

Abstract

The present invention discloses a control system for a high-intensity proton accelerator in a boron neutron capture therapy system, belonging to the technical field of proton beam control. The method specifically includes: generating a proton beam through an ion source, and performing secondary acceleration on the generated initial proton beam. Using an electromagnetic lens to focus and regulate the proton beam, real-time monitoring of the beam position and intensity, path adjustment through feedback control, guiding the proton beam to the lithium target area through a beam transmission pipeline, using a targeting control strategy to accurately locate the proton beam strike area, real-time monitoring of the operating state of the high-intensity proton accelerator, including parameters such as temperature, pressure, and current, setting safety thresholds, and automatically triggering an alarm and starting an emergency handling procedure when any parameter exceeds the safety range. Through the present invention, the flow rate and energy of the proton beam can be accurately controlled.

Description

Technical Field

[0001] The present invention belongs to the technical field of proton beam control, specifically, a control system for a high-current proton accelerator in a boron neutron capture therapy system. Background Art

[0002] Boron Neutron Capture Therapy (BNCT) is a cutting-edge radiotherapy technique dedicated to treating malignant tumors, especially for cancer types that are difficult to treat by traditional methods, such as glioblastoma and recurrent head and neck cancers. The treatment process of BNCT relies on two key elements: a targeted boron drug and an efficient neutron source.

[0003] The boron drug used in BNCT usually contains the boron-10 isotope, which has a relatively high neutron capture cross-section. When patients receive an injection or oral administration of these boron-containing compounds, boron accumulates selectively in tumor cells, while the content in normal cells is relatively low. This targeting is one of the core advantages of BNCT, enabling precise attacks on cancer cells and minimizing damage to normal tissues to the greatest extent.

[0004] Another key element of BNCT is the neutron source. Traditionally, nuclear reactors have been used as the neutron source. However, nuclear reactors are not only expensive and complex but also face problems of radiation safety and site limitations. To overcome these obstacles, in recent years, neutron sources based on proton accelerators have gradually become a research and application hotspot. A high-current proton accelerator is a device that can generate high-intensity proton beams, and these proton beams produce neutrons through a target reaction. Commonly used target materials include beryllium, lithium, and carbon, etc. When the proton beam impacts these materials with sufficient energy, a high flux of neutrons suitable for BNCT is generated.

[0005] In a BNCT system, the control technology of the proton accelerator is crucial. First, the energy and current intensity of the proton beam must be precisely controlled to ensure that the generated neutrons meet the treatment standards. Second, the stability of the proton accelerator directly affects the treatment effect. If the proton beam fluctuates too much, it may lead to instability in neutron generation, thereby affecting the accuracy of the treatment. However, current technologies have problems such as insufficient control accuracy and complex operation. Summary of the Invention

[0006] Aiming at the deficiencies of the prior art, the present invention proposes a control system for a high-current proton accelerator in a boron neutron capture therapy system, which improves the accelerator control strategy and optimizes the performance to enhance the stability and output accuracy of the proton beam current.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] The control system of the high-intensity proton accelerator for boron neutron capture therapy system includes: a generation and acceleration module, a regulation and focusing module, a transmission and targeting module, and a safety detection module;

[0009] The generation and acceleration module is used to generate an initial proton beam and accelerate the generated initial proton beam;

[0010] The regulation and focusing module is used to monitor the position and intensity of the proton beam in real time, focus and regulate the proton beam, and adjust it through a feedback control strategy;

[0011] The transmission and targeting module is used to transmit the proton beam through a beam transmission pipeline to the lithium target area and bombard the lithium target to generate neutrons;

[0012] The safety detection module is used to monitor the operating status of the high-intensity proton accelerator in real time, detect abnormal situations, automatically stop the proton source when a fault occurs, issue an alarm, and start an emergency handling procedure.

[0013] Specifically, the generation and acceleration module includes a proton beam generation unit and a proton beam acceleration unit;

[0014] The proton beam generation unit is used to generate an initial proton beam through an ion source and determine the initial current I of the generated proton beam 0 ;

[0015] The proton beam acceleration unit is used to accelerate the generated initial proton beam.

[0016] Specifically, accelerating the generated initial proton beam includes:

[0017] Using a radio frequency electric field, the generated initial proton beam is introduced into the first acceleration section for primary acceleration, and the energy of the proton beam after primary acceleration is E 2 ;

[0018] Using a radio frequency cavity, the proton beam after primary acceleration is introduced into the second acceleration section for secondary acceleration, and the energy of the proton beam after secondary acceleration is E 3 。

[0019] Specifically, the regulation and focusing module includes: a proton beam regulation unit and a proton beam focusing unit;

[0020] The proton beam regulation unit is used to adjust the path of the proton beam using an electromagnetic lens;

[0021] The proton beam focusing unit is used to focus and correct the proton beam.

[0022] Specifically, the regulation and focusing module further includes:

[0023] An electromagnetic lens is used to generate a magnetic field, applying a Lorentz force to the moving proton beam to change the motion trajectory of the proton beam. The control equation formula for the proton beam hitting position is as follows:

[0024] P(t)=P ref +K 2 ×(L ref -L(t));

[0025] Among them, P(t) represents the control equation of the proton beam hitting position, that is, the position where the proton beam hits, P ref represents the reference position, L ref represents the reference path length, L(t) represents the real-time path length, and K 2 represents the proportional control coefficient;

[0026] Focus the proton beam. The specific formula for the focusing ability of the electromagnetic lens is:

[0027] ,

[0028] Among them, f represents the focusing ability of the electromagnetic lens, B represents the magnetic field strength, r represents the radius of the proton beam, v represents the velocity of the proton beam, and q e represents the electron charge;

[0029] Monitor the position and intensity of the proton beam in real time and adjust through a feedback control strategy. The specific formula is:

[0030] N(t)=N ref +K 3 ×(F ref -F(t));

[0031] Among them, N(t) represents the intensity of the proton beam, N ref represents the intensity of the reference proton beam, F ref represents the reference feedback signal, F(t) represents the real-time feedback signal, and K 3 represents the proportional control coefficient.

[0032] Specifically, the transmission and targeting module includes: a proton beam transmission unit and a proton beam targeting control unit;

[0033] The proton beam transmission unit is used to guide the focused proton beam to the lithium target area through a beam transmission pipeline;

[0034] The proton beam targeting control unit is used to accurately position the proton beam using a targeting control strategy.

[0035] Specifically, guiding the focused proton beam to the lithium target area through a beam transmission pipeline includes:

[0036] During the transmission of the proton beam, due to the interaction with the residual gas molecules in the transmission pipeline, the energy of the proton beam will be lost. An energy loss model is established to calculate the energy loss of the proton beam during transmission. The specific formula is as follows:

[0037] ;

[0038] Wherein, represents the energy loss rate of the proton beam during transmission, m e represents the rest mass of an electron, c represents the speed of light, h represents the charge number of a proton, e represents the elementary charge, represents the ratio of the proton velocity to the speed of light, and I represents the ionization energy of the transmission channel.

[0039] Specifically, the targeting control strategy in the proton beam targeting control unit includes:

[0040] Obtain the measurement data of the sensor, including laser ranging data, imaging data, and lithium target motion detection data, and fuse the obtained sensor measurement data. The fused data is D fused ;

[0041] Establish a real-time motion compensation model to compensate for the motion of the lithium target. Set the motion speed of the lithium target as V M , and the motion direction vector is , calculate the displacement of the lithium target at time t 1 ;

[0042] The proton beam is transmitted in three-dimensional space. Perform comprehensive correction on the three-dimensional space. Set the position of the fused lithium target in the three-dimensional space as (x, y, z) fused , and the position coordinates of the lithium target after motion compensation are (x, y, z) cor .

[0043] Specifically, the targeting control strategy in the proton beam targeting control unit further includes: controlling the striking path of the proton beam. The specific formula is as follows:

[0044] ,

[0045] Wherein, U(t 1 +1) represents the control signal of the striking path of the proton beam at time t 1 +1, U(t 1 ) represents the control signal of the striking path of the proton beam at time t 1 , K p , K i and K d ​respectively represent the proportional, integral, and derivative control gains, represents t 1 the hitting deviation of the proton beam current at time t, represents t 1 the hitting deviation of the proton beam current at time t - 1, represents the hitting deviation of the proton beam current at time g, represents the time interval.

[0046] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0047] 1. The present invention provides a high-intensity proton accelerator control system for a boron neutron capture therapy system, which can accurately control the flow rate and energy of the proton beam, ensuring that the proton beam can stably and uniformly hit the lithium target area, thereby generating the required neutrons.

[0048] 2. The present invention provides a high-intensity proton accelerator control system for a boron neutron capture therapy system. By optimizing the acceleration and control process of the proton beam, unnecessary energy losses and non-uniformities can be effectively reduced, and errors can be minimized.

[0049] 3. The present invention provides a high-intensity proton accelerator control system for a boron neutron capture therapy system, which allows real-time feedback for adjustment and dynamically optimizes the parameters of the proton beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 is the architecture diagram of the high-intensity proton accelerator control system for the boron neutron capture therapy system provided by the present invention;

[0051] Figure 2 is the flow chart of proton beam acceleration provided by the present invention;

[0052] Figure 3 is the flow chart of proton beam targeting control provided by the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0053] In order to make the technical means, creative features, achieved purposes, and functions of the present invention easy to understand, in the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. In addition, the terms "No. 1", "No. 2", "No. 3" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. The present invention will be further described below in conjunction with specific embodiments.

[0054] Example 1

[0055] Please refer to Figure 1 , an embodiment provided by the present invention: a control system for a high-intensity proton accelerator of a boron neutron capture therapy system, comprising: a generation and acceleration module, a regulation and focusing module, a transmission and targeting module, and a safety detection module;

[0056] The generation and acceleration module is used to generate an initial proton beam and accelerate the generated initial proton beam;

[0057] The regulation and focusing module is used to monitor the position and intensity of the proton beam in real time, focus and regulate the proton beam, and adjust it through a feedback control strategy;

[0058] The transmission and targeting module is used to transmit the proton beam through a beam transmission pipeline to the lithium target area, accurately position the proton beam by using a targeting control strategy, and bombard the lithium target;

[0059] The safety detection module is used to monitor the operating state of the high-intensity proton accelerator in real time, detect abnormal situations, automatically stop the proton source when a fault occurs, issue an alarm, and start an emergency handling procedure.

[0060] The generation and acceleration module includes: a proton beam generation unit and a proton beam acceleration unit;

[0061] The proton beam generation unit is used to generate an initial proton beam through an ion source and determine the initial current I of the generated proton beam 0 ;

[0062] The ion source usually uses hydrogen as the working gas and generates protons (H + ions) through ionization. These protons are guided to the initial section of the accelerator under the action of an electric field. The formula for the initial current I of the proton beam 0 is: , where q e represents the electron charge, with the unit of Coulomb, N represents the number of protons, that is, the number of protons generated within time t 7 , t 7 represents time;

[0063] The design and operating parameters of the ion source need to be precisely controlled to ensure that the generated proton beam has a stable initial current I 0 . The stability of the initial current is a prerequisite for the stability of the beam energy and intensity during the subsequent acceleration process. The methods for precise control of the ion source include: 1) precise adjustment of ion source parameters, including gas (hydrogen) flow control, ionization voltage and current control, and magnetic field regulation; 2) real-time monitoring and feedback adjustment; 3) environmental factor control, including temperature control, control of the vacuum system, and electromagnetic shielding; 4) regular calibration and maintenance of the ion source;

[0064] The proton beam acceleration unit is used to accelerate the generated initial proton beam.

[0065] The acceleration of the generated initial proton beam includes:

[0066] Step S101: Using a radio frequency electric field, the generated initial proton beam is introduced into the first acceleration section for primary acceleration. The specific formula for the energy of the proton beam after primary acceleration is:

[0067] ,

[0068] where E 2 represents the energy of the proton beam after primary acceleration, E RFQ represents the amplitude of the radio frequency electric field, f RFQ represents the frequency of the radio frequency electric field, z represents the position of the proton in the first acceleration section, L represents the total length of the first acceleration section, t represents the primary acceleration time, k represents the wave number, which is related to the wavelength of the radio frequency electric field, cos() represents the cosine function, q represents the charge of the proton beam, and E 1 represents the initial energy of the proton beam;

[0069] After preliminary acceleration, the protons enter a radio frequency quadrupole accelerator (RFQ). The RFQ uses a radio frequency electric field to further accelerate the protons through a quadrupole structure. The electric field in the RFQ not only accelerates the protons but also focuses the beam, making the proton beam more concentrated;

[0070] Step S102: Using a radio frequency cavity, the proton beam after primary acceleration is introduced into the second acceleration section for secondary acceleration. The specific formula for the energy of the proton beam after secondary acceleration is:

[0071] ,

[0072] where E 3 represents the energy of the proton beam after secondary acceleration, E Lin represents the amplitude of the radio frequency cavity electric field, f Lin represents the frequency of the radio frequency cavity electric field, l represents the length of the radio frequency cavity, represents the phase difference of the radio frequency cavity electric field, represents the secondary acceleration time.

[0073] After acceleration in the RFQ section, the protons enter a linear accelerator (Linac) for further acceleration. The Linac consists of multiple radio frequency cavities, and each radio frequency cavity increases the energy of the protons through a radio frequency electric field.

[0074] The advantages of using secondary acceleration are as follows: 1) The structure of the electrostatic accelerator is relatively simple, which can quickly accelerate protons in the initial stage, provide sufficient energy within a short distance to enable protons to enter subsequent acceleration, and has low energy consumption; 2) It can focus the beam during the acceleration process, reduce the divergence of the proton beam, and improve the acceleration efficiency; 3) It can provide extremely high energy gain, gradually increase the proton energy over a long distance, and by adjusting the frequency and phase of the RF cavity, the energy and acceleration process of protons can be flexibly controlled.

[0075] The regulation and focusing module includes: a proton beam regulation unit and a proton beam focusing unit;

[0076] The proton beam regulation unit is used to adjust the path of the proton beam using an electromagnetic lens;

[0077] The proton beam focusing unit is used to focus and correct the proton beam.

[0078] The regulation and focusing module further includes:

[0079] Using an electromagnetic lens to generate a specific magnetic field, applying a Lorentz force to the high-speed moving proton beam to change the motion trajectory of the proton beam. The formula for the proton beam hitting position control equation is:

[0080] P(t)=P ref +K 2 ×(L ref -L(t));

[0081] Where P(t) represents the proton beam hitting position control equation, that is, the position where the proton beam hits, P ref represents the reference position, L ref represents the reference path length, L(t) represents the real-time path length, and K 2 represents the proportional control coefficient;

[0082] In this embodiment, the core principle of the proton beam hitting position control equation formula lies in precisely controlling the hitting position of the proton beam on the neutron target to ensure that the generated neutron beam has a uniform direction and intensity. Specifically, the formula describes how the position control system of the proton beam adjusts according to the difference between the reference path length L ref and the real-time path length L(t). When the real-time path length L(t) deviates from the reference path length L ref , the system calculates the required adjustment amount based on this deviation through the proportional control coefficient K 2 to correct the hitting position P(t) of the proton beam, ensuring that the hit position on the neutron target is always at the predetermined reference position. By adjusting the hitting position of the proton beam in real time, it is ensured that the hit intensities at different positions on the neutron target are uniform, having better uniformity;

[0083] Focus the proton beam. The specific formula for the focusing ability of the electromagnetic lens is as follows:

[0084] ,

[0085] where f represents the focusing ability of the electromagnetic lens, that is, the degree of convergence or divergence of the proton beam; B represents the magnetic field strength, which is used to adjust the movement direction of the proton beam; r represents the radius of the proton beam, that is, the transverse size of the proton beam; v represents the velocity of the proton beam, which is proportional to the energy of the proton beam.

[0086] Monitor the position and intensity of the proton beam in real time and adjust through a feedback control strategy. The specific formula is as follows:

[0087] N(t)=N ref +K 3 ×(F ref -F(t));

[0088] where N(t) represents the intensity of the proton beam, N ref represents the intensity of the reference proton beam, F ref represents the reference feedback signal, F(t) represents the real-time feedback signal, and K 3 represents the proportional control coefficient.

[0089] In this embodiment, the principle of the feedback control strategy is to dynamically adjust the parameters of the proton source and the acceleration cavity by monitoring the intensity of the neutron beam in real time to maintain the stability of the neutron beam. Specifically, this formula describes the adjustment process of the neutron beam intensity N(t). It calculates the required adjustment amount by comparing the real-time feedback signal F(t) and the reference feedback signal F ref , so that the neutron beam intensity N(t) approaches the predetermined reference value N ref . When the real-time feedback signal F(t) deviates from the reference feedback signal F ref , the system corrects the neutron beam intensity by adjusting the proportional control coefficient K 3 to make it tend to the reference value N ref , thereby ensuring the stability and uniformity of the neutron beam. Through real-time monitoring and feedback control, it can quickly respond to changes in the proton beam intensity, automatically adjust the parameters of the proton source and the acceleration cavity, and ensure that the proton beam intensity remains stable;

[0090] The working environment of the ion source has an important impact on its performance. Factors such as temperature, pressure, and external electromagnetic interference can all cause instability of the proton beam current. Therefore, controlling environmental factors through the following methods is also an important measure to ensure beam current stability: 1) Temperature control: Install high-precision temperature control equipment near the ion source to ensure a constant temperature in the working environment and prevent the impact of temperature fluctuations on the ion generation process; 2) Stability of the vacuum system: The generation of the proton beam current usually takes place in a vacuum environment. An efficient vacuum system can prevent air molecules from interfering with ion movement and ensure the stable operation of the ion source. 3) Electromagnetic shielding: Set up an electromagnetic shielding layer around the ion source to prevent external electromagnetic fields from interfering with the electric and magnetic fields of the ion source, thereby ensuring the stability of the proton beam current.

[0091] The transmission and targeting module includes: a proton beam current transmission unit and a proton beam current targeting control unit;

[0092] The proton beam current transmission unit is used to guide the focused proton beam current to the lithium target area through a beam current transmission pipeline;

[0093] The proton beam current targeting control unit is used to precisely locate the proton beam current using a targeting control strategy.

[0094] In this embodiment, the transmission and targeting of the proton beam current are key steps in neutron generation. After the proton beam current is accelerated and focused, it needs to be guided to the lithium target area through a transmission pipeline. During this process, energy loss and beam current scattering effects must be strictly controlled to ensure that the proton beam can maintain sufficient energy and stability and finally accurately strike the targeting area. In addition, the targeting control strategy needs to have extremely high precision to ensure that the proton beam current accurately bombards the lithium target to generate neutrons;

[0095] Guiding the focused proton beam current to the lithium target area through a beam current transmission pipeline includes:

[0096] During the transmission process of the proton beam current, due to the interaction with residual gas molecules in the transmission pipeline, the energy of the proton beam current will be lost. An energy loss model is established to calculate the energy loss of the proton beam current during the transmission process. The specific formula is:

[0097] ;

[0098] Among them, represents the energy loss rate of the proton beam current during the transmission process, that is, the energy loss of the proton beam current per unit length, m e represents the rest mass of an electron, c represents the speed of light, h represents the charge number of a proton, e represents the elementary charge, represents the ratio of the proton velocity to the speed of light, and I represents the ionization energy of the transmission channel, which is determined according to the medium of the transmission channel;

[0099] In this embodiment, the principle of the above formula is as follows: When a charged particle passes through a substance, it mainly loses energy through interactions with electrons in the substance. The main forms of such interactions include: Ionization: The charged particle collides with an electron in the substance, kicking the electron out of the atom and forming an ion pair. This process consumes a part of the kinetic energy of the charged particle; Excitation: The charged particle interacts with an electron in the substance, causing the electron to transition from a lower energy level to a higher energy level without completely detaching from the atom. This process also consumes the kinetic energy of the charged particle; Considering the relativistic effect, Coulomb interaction, and the binding energy of electrons, reflects the relationship that the charge number of a proton is inversely proportional to the square of its velocity. The faster the proton velocity, the smaller the energy loss rate, because a high-speed moving proton spends less time and loses less energy when interacting with the substance, includes the logarithmic relationship between the proton velocity and the ionization energy of the substance. This term reflects that high-energy protons mainly lose energy through ionization when passing through the substance, is a correction for the proton kinetic energy and scattering effect, considering the relativistic effect of the proton in the high-energy state;

[0100] To reduce energy loss, the following methods can be used to optimize the transmission:

[0101] 1) Increase the vacuum degree: Reduce the density of residual gas molecules in the transmission pipeline, lower the collision probability between protons and gas molecules, and thus reduce energy loss; 2) Optimize the inner wall design of the pipeline: Use materials with low adsorption rates to reduce gas residue and secondary scattering effects; 3) Control the transmission distance: Try to shorten the transmission distance of the proton beam in the design to reduce the total energy loss;

[0102] Methods for dealing with beam scattering effects: The proton beam may scatter during transmission due to interactions with the pipeline wall or minute inhomogeneities within the pipeline. The scattering effect can cause the beam to diverge and reduce the targeting accuracy. To reduce the scattering effect, the following measures can be taken: 1) Install a beam calibrator: Install a beam calibrator at key positions in the transmission pipeline to adjust the direction and divergence angle of the proton beam in real time; 2) Regularly maintain the pipeline system: Ensure that the inner surface of the transmission pipeline is smooth and uniform through regular cleaning and maintenance to reduce the occurrence of scattering effects.

[0103] As Figure 3 shown, the said targeting control strategy includes:

[0104] Step S201: Obtain the measurement data of the sensor, including laser ranging data, imaging data, and lithium target motion detection data, and fuse the obtained sensor measurement data. The specific formula is:

[0105] ,

[0106] Among them, D fused represents the estimated value of the lithium target position, D L represents the laser ranging data, D I represents the imaging data, D M represents the patient motion detection data, w L 、w I and w M respectively represent the weight coefficients of the laser ranging, imaging, and patient motion detection data, and satisfy w L +w I +w M = 1;

[0107] In this embodiment, information from different data sources (such as laser ranging, imaging systems, motion monitoring, etc.) is fused, and a more accurate estimated value of the target position is obtained through weighted averaging. This fusion method can reduce the errors that may be brought by a single data source, utilize the advantages of each data source, and provide more reliable positioning information;

[0108] Step S202: Establish a real-time motion compensation model to compensate for the motion of the lithium target. Set the motion speed of the lithium target to V M , and the motion direction vector is . The displacement calculation formula of the lithium target at time t 1 is: , where represents the displacement of the lithium target at time t 1 ;

[0109] In this embodiment, due to the physiological movements of the patient (such as breathing and heartbeat), which will indirectly cause changes in the position of the lithium target, by real-time monitoring and calculating the motion displacement of the lithium target, the system can timely correct the target position, so that the proton beam can follow the movement of the lithium target, ensuring that the proton beam is always accurately positioned in the lithium target area;

[0110] Step S203: The proton beam is transmitted in three-dimensional space, and comprehensive correction of the three-dimensional space is performed. Set the fused lithium target position in the three-dimensional space to (x, y, z) fused . The three-dimensional correction formula after motion compensation is:

[0111] ,

[0112] where (x, y, z) cor represents the lithium target position after motion compensation, represents the displacement of the lithium target motion in three-dimensional space;

[0113] Step S204: Control the hitting path of the proton beam. The specific formula is:

[0114] ,

[0115] wherein, U(t 1 +1) represents the control signal of the proton beam strike path at time t 1 +1, U(t 1 ) represents the control signal of the proton beam strike path at time t 1 , K p , K i and K d represent the proportional, integral and derivative control gains respectively, represents the strike deviation of the proton beam at time t 1 , represents the strike deviation of the proton beam at time t 1 -1, represents the strike deviation of the proton beam at time g, represents the time interval.

[0116] In this embodiment, when the proton beam is transmitted in three-dimensional space, the system needs to correct its path to ensure accurate striking of the target. Through feedback control, the system monitors the strike position of the proton beam in real time and adjusts the path according to the deviation, gradually reducing the deviation so that the proton beam accurately reaches the target position. The three-dimensional space correction and feedback control can continuously optimize the path of the proton beam and improve the stability and accuracy of the system;

[0117] This embodiment considers various uncertain factors and greatly enhances the robustness of the system through an adaptive control strategy, making it show better stability and reliability in practical applications.

[0118] Embodiment 2

[0119] Another embodiment provided by the present invention: A control method for a high-intensity proton accelerator of a boron neutron capture therapy system, comprising the following specific steps:

[0120] Step S1: Generate an initial proton beam through an ion source and perform secondary acceleration on the generated initial proton beam;

[0121] Step S2: Use an electromagnetic lens to focus and regulate the proton beam, monitor the beam position and intensity in real time, and adjust the path through feedback control;

[0122] Step S3: Guide the proton beam to the lithium target area through a beam transmission pipeline and accurately locate the proton beam strike area using a targeting control strategy;

[0123] Step S4: Monitor the operating state of the high-intensity proton accelerator in real time, including parameters such as temperature, pressure, and current, set safety thresholds, and automatically trigger an alarm and start an emergency handling procedure when any parameter exceeds the safety range.

[0124] In this embodiment, Figure 2 the steps of accelerating the proton beam twice are described; Figure 3 the steps of compensating and controlling the proton beam are described.

[0125] In the above technical solutions provided in the embodiments of the present application, the parts that are consistent with the corresponding technical solutions in the prior art in terms of implementation principles are not described in detail to avoid excessive elaboration.

[0126] As described above in the specific embodiments, the purpose, technical solutions, and beneficial effects of the present invention are further described in detail. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A high-current proton accelerator control system for a boron neutron capture therapy system, characterized in that: include: Generation and acceleration module, regulation and focusing module, transmission and targeting module and safety detection module; The generation and acceleration module is used to generate an initial proton beam and accelerate the generated initial proton beam; The control and focusing module is used to monitor the position and intensity of the proton beam in real time, focus and control the proton beam, and adjust it through a feedback control strategy; The transmission and targeting module is used to transmit the proton beam to the lithium target area through the beam transmission pipeline, and use the targeting control strategy to accurately position the proton beam to bombard the lithium target and generate neutrons; The safety detection module is used to monitor the operating status of the high-current proton accelerator in real time and detect abnormal conditions. When a fault occurs, the system automatically stops the proton source, sounds an alarm, and starts an emergency treatment procedure; The transmission and targeting module includes: a proton beam transmission unit and a proton beam targeting control unit; The proton beam transmission unit is used to guide the focused proton beam to the lithium target area through the beam transmission pipeline; The proton beam targeting control unit is used to use a targeting control strategy to accurately position the proton beam to bombard the lithium target; The method of guiding the focused proton beam to the lithium target area through a beam transmission pipeline includes: During the transmission of the proton beam, an energy loss model is established to calculate the energy loss of the proton beam during the transmission process. The specific formula is: ； in, represents the energy loss rate of the proton beam during transmission, m e represents the mass of an electron at rest, c represents the speed of light, h represents the charge of a proton, and e represents the elementary charge. represents the ratio of the proton speed to the speed of light, and I represents the ionization energy of the transmission channel; The targeting control strategy in the proton beam targeting control unit includes: Acquire the sensor measurement data, including laser ranging data, imaging data and lithium target motion detection data, and fuse the acquired sensor measurement data. The fused data is D fused ; A real-time motion compensation model is established to compensate for the motion of the lithium target, and the motion speed of the lithium target is set to V M , the motion direction vector is , calculate the displacement of the lithium target at time t1 , ,in, represents the displacement of the lithium target at time t1; The proton beam is transmitted in three-dimensional space, and the three-dimensional space is comprehensively corrected to set the position of the fused lithium target in the three-dimensional space to (x, y, z) fused , the coordinates of the lithium target position after motion compensation are (x, y, z) cor ; The targeting control strategy in the proton beam targeting control unit also includes: controlling the striking path of the proton beam, and the specific formula is: ， Among them, U(t1+1) represents the control signal of the proton beam impact path at time t1+1, U(t1) represents the control signal of the proton beam impact path at time t1, and K p , K i and K d denote the proportional, integral and differential control gains respectively, represents the impact deviation of the proton beam at time t1, represents the impact deviation of the proton beam at time t1-1, represents the impact deviation of the proton beam at time g, Indicates a time interval.

2. The high-current proton accelerator control system of the boron neutron capture therapy system according to claim 1, characterized in that: The generation and acceleration module includes a proton beam generation unit and a proton beam acceleration unit; The proton beam generating unit is used to generate an initial proton beam through an ion source and determine an initial current I0 of the generated proton beam; The proton beam acceleration unit is used to accelerate the generated initial proton beam.

3. The high-current proton accelerator control system of the boron neutron capture therapy system according to claim 2, characterized in that: The step of accelerating the generated initial proton beam comprises: Using a radio frequency electric field, the generated initial proton beam is introduced into the first acceleration section for one acceleration, and the proton beam energy after one acceleration is E2; The proton beam after the first acceleration is introduced into the second acceleration section for secondary acceleration by using a radio frequency cavity. The energy of the proton beam after the secondary acceleration is E3.

4. The high-current proton accelerator control system of the boron neutron capture therapy system according to claim 1, characterized in that: The control and focusing module includes: a proton beam control unit and a proton beam focusing unit; The proton beam regulating unit is used to adjust the path of the proton beam using an electromagnetic lens; The proton beam focusing unit is used to focus and correct the proton beam.

5. The high-current proton accelerator control system of the boron neutron capture therapy system according to claim 4, characterized in that: The control and focusing module further includes: An electromagnetic lens is used to generate a magnetic field, exerting a Lorentz force on the moving proton beam to change the trajectory of the proton beam. The equation for controlling the impact position of the proton beam is: P(t)=P ref +K2×(L ref -L(t)); Among them, P(t) represents the proton beam impact position control equation, that is, the position of the proton beam impact, P ref Indicates the reference position, L ref represents the reference path length, L(t) represents the real-time path length, and K2 represents the proportional control coefficient; To focus the proton beam, the specific formula of the focusing ability of the electromagnetic lens is: ， Among them, f represents the focusing ability of the electromagnetic lens, B represents the magnetic field strength, r represents the radius of the proton beam, v represents the speed of the proton beam, and q e represents the charge of an electron; The proton beam position and intensity are monitored in real time and adjusted through feedback control strategy. The specific formula is: N(t)=N ref +K3×(F ref -F(t)); Where N(t) represents the intensity of the proton beam, N ref represents the intensity of the reference proton beam, F ref represents the reference feedback signal, F(t) represents the real-time feedback signal, and K3 represents the proportional control coefficient.

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