A method and system for synergistically controlling beam energy of a cyclotron, an electronic device, and a medium

Abstract

The application discloses a kind of cyclotron beam energy synergic control method and system, wherein the method includes the following steps: obtaining the vacuum pressure fluctuation deviation value and water cooling temperature fluctuation deviation value of current control cycle;The vacuum pressure fluctuation deviation value and water cooling temperature fluctuation deviation value of current control cycle are converted into feedforward compensation control amount;The tracking deviation value of target reference input and observation state of current control cycle is obtained respectively, and actual beam energy output value is obtained, to obtain the adaptive gain of nonlinear state error feedback, and then obtain nonlinear feedback control amount;The feedforward compensation control amount and nonlinear feedback control amount of current control cycle are superimposed to obtain the final control instruction, and are converted into analog voltage signal, output to the beam energy control execution mechanism of cyclotron, to act on the execution mechanism;Enter next control cycle, and repeat the above steps, realize cyclotron beam energy dynamic regulation.

Description

Technical Field

[0001] This invention relates to the field of particle accelerator control technology, specifically to a method and system for coordinated control of beam energy in a cyclotron accelerator. Background Technology

[0002] As the core equipment of the boron neutron capture therapy (BNCT) system, the quality of the beam generated by the cyclotron directly determines the accuracy and safety of radiotherapy, and the stability of the beam energy is the most critical indicator for measuring beam quality. However, the cyclotron is a complex nonlinear system, consisting of multiple subsystems such as the beam energy system, vacuum system, radio frequency system, and water cooling system.

[0003] In actual operation, there are significant multiphysics coupling effects between the subsystems. For example, fluctuations in beam intensity can cause changes in pressure within the vacuum chamber, which in turn affects the stability of beam transmission; small fluctuations in cooling water temperature can cause thermal expansion and contraction of the high-frequency cavity, leading to resonant frequency drift, which directly interferes with the accelerating voltage and causes beam energy fluctuations.

[0004] Existing cyclotron control strategies primarily focus on the independent adjustment of individual subsystems, often employing traditional PID control or even manual open-loop adjustment methods. Manual open-loop adjustment heavily relies on operator experience, resulting in low efficiency and poor repeatability. PID control, on the other hand, mainly adjusts based on system output errors, lacking mechanisms for predicting and actively mitigating measurable multi-source coupled disturbances such as vacuum pressure and chamber temperature. Due to the failure to adequately consider the dynamic coupling mechanisms within the system, existing technologies often suffer from bottlenecks such as long settling times, large overshoot, insufficient steady-state accuracy, and limited anti-interference capabilities when facing complex operating condition switching or superimposed multi-source disturbances. These limitations make it difficult to meet the extremely high stability requirements of beam energy in high-level BNCT treatment. Summary of the Invention

[0005] The purpose of this invention is to provide a method and system for coordinated control of beam energy in a cyclotron accelerator, in order to solve the technical problems that existing cyclotron control strategies often focus on the independent adjustment of a single subsystem. When faced with complex operating condition switching or the superposition of multiple disturbances, they often have problems such as long adjustment time, large overshoot, insufficient steady-state accuracy, and limited anti-interference ability, which make it difficult to meet the extremely high stability requirements of beam energy for high-level BNCT treatment.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a method for coordinated control of beam energy in a cyclotron accelerator, comprising the following steps:

[0008] S1. Obtain the real-time vacuum pressure fluctuation deviation value and water cooling temperature fluctuation deviation value of the cyclotron system in the current control cycle.

[0009] S2. Based on the pre-built cyclotron beam energy fluctuation coupling model, the vacuum pressure fluctuation deviation value and the water cooling temperature fluctuation deviation value in the current control cycle are converted into feedforward compensation control quantities.

[0010] S3. Obtain the tracking deviation between the target reference input and the observed state in the current control cycle, as well as the actual beam energy output value in the main control loop of the current control cycle, to obtain the adaptive gain of the nonlinear state error feedback, and then obtain the nonlinear feedback control quantity.

[0011] S4. The feedforward compensation control quantity and the nonlinear feedback control quantity of the current control cycle are superimposed to obtain the final control command;

[0012] S5. Convert the final control command into an analog voltage signal and output it to the beam energy control actuator of the cyclotron to operate the actuator;

[0013] S6. Enter the next control cycle and repeat steps S1 to S5 to achieve dynamic adjustment of the cyclotron beam energy and achieve closed-loop stable adjustment of energy fluctuations.

[0014] Furthermore, in step S1, the vacuum pressure fluctuation deviation value and the water cooling temperature fluctuation deviation value are obtained through the following steps:

[0015] S1.1 Obtain the real-time vacuum pressure, cooling water outlet temperature, and actual beam energy output value in the main control loop of the cyclotron system;

[0016] S1.2 Calculate the vacuum pressure fluctuation deviation value and the water cooling temperature fluctuation deviation value.

[0017] Furthermore, the expression for the cyclotron beam energy fluctuation coupling model is as follows:

[0018] ;

[0019] In the formula, Here, k represents the system's nonlinear coefficients, P(t) is the vacuum pressure in Pa, and k is the pressure in Pa. vac Vacuum pressure-energy coupling coefficient, MeV / Pa, T cw (t) represents the water cooling temperature, K; k cw The water cooling temperature-energy coupling coefficient, MeV / K. Let t be the total system disturbance and t be the sampling time.

[0020] Furthermore, step S3 specifically includes the following steps:

[0021] S3.1 Obtain the observation error and the actual beam energy output value in the main control loop under the observation state, and obtain the total disturbance estimate based on the observation error and the actual beam energy output value;

[0022] S3.2. Based on the total disturbance estimate, obtain the adaptive gain of the nonlinear state error feedback;

[0023] S3.3 Obtain the tracking deviation values ​​of the target reference input and the observation state respectively, and combine them with the adaptive gain to obtain the nonlinear feedback control quantity.

[0024] Furthermore, the formula for calculating the feedforward compensation control quantity is as follows:

[0025] ;

[0026] In the formula, b0 is the nominal control input gain, k vac Let k be the coupling transfer coefficient between vacuum pressure and beam energy fluctuations. cw The water cooling temperature-energy coupling coefficient, This represents the deviation value of vacuum pressure fluctuation. This represents the deviation value of water cooling temperature fluctuation.

[0027] Furthermore, the expression for the nonlinear feedback control quantity is:

[0028] ;

[0029] In the formula, For adaptive gain, α3 and α4 are the corresponding feedback nonlinearity factors. is a nonlinear function, where e is the error, α1 is the nonlinear factor, and δ is the limit of the linear region width.

[0030] Furthermore, the final control command is obtained through a final control law, the expression of which is:

[0031] ;

[0032] In the formula, For the first Feedforward compensation amount per control cycle For the first The nonlinear feedback control quantity for each control cycle, b0 is the nominal control input gain, and k vac Let k be the vacuum pressure-energy coupling coefficient. cw The water cooling temperature-energy coupling coefficient, This represents the deviation value of vacuum pressure fluctuation. This represents the deviation value of water cooling temperature fluctuation. It is a nonlinear feedback control quantity. This is the estimated total disturbance.

[0033] Secondly, the present invention also provides a cyclotron beam energy coordinated control system for implementing the cyclotron beam energy coordinated control method described above, comprising:

[0034] The system parameter acquisition unit is used to acquire the real-time vacuum pressure fluctuation deviation value and water cooling temperature fluctuation deviation value of the cyclotron system for the corresponding control cycle, the tracking deviation value between the target reference input and the observation state, and the actual beam energy output value in the main control loop.

[0035] The multivariable feedforward compensation control quantity calculation unit is used to convert the vacuum pressure fluctuation deviation value and the water cooling temperature fluctuation deviation value of the corresponding control cycle into feedforward compensation control quantity based on the pre-built cyclotron beam energy fluctuation coupling model.

[0036] The nonlinear feedback control quantity calculation unit is used to obtain the adaptive gain of the nonlinear state error feedback based on the tracking deviation value between the target reference input and the observed state in the corresponding control cycle, and the actual beam energy output value in the main control loop in the corresponding control cycle, and then obtain the nonlinear feedback control quantity.

[0037] The collaborative control command synthesis unit is used to superimpose the feedforward compensation control quantity and the nonlinear feedback control quantity of the corresponding control cycle to obtain the final control command, and convert the final control command into an analog voltage signal, which is then output to the beam energy control actuator of the cyclotron to operate the actuator.

[0038] Thirdly, the present invention also provides an electronic device, including a processor and a memory, wherein the processor is coupled to the memory; the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory to realize the cyclotron beam energy coordinated control method as described above.

[0039] Fourthly, the present invention also provides a computer-readable storage medium for storing a computer program, which is executed by a processor to implement the cyclotron beam energy cooperative control method as described above.

[0040] This invention offers the following advantages: By establishing quantitative coupling relationships between vacuum pressure and beam intensity, water cooling temperature and high-frequency cavity voltage, it reveals the multiphysics disturbance path. A multivariable feedforward compensation layer is introduced, enabling the system to actively cancel disturbances before they reach the energy output. The model exhibits robustness, and the established gain adjustment mechanism adaptively optimizes the observation intensity based on the total disturbance strength. The beam energy control system possesses excellent dynamic response speed, converging rapidly when faced with sudden large disturbances. In the steady-state phase, it effectively suppresses noise amplification from the observer, enhancing the stability of the control system. The technical solution of this invention significantly improves the steady-state accuracy and disturbance rejection capability of the beam energy. Attached Figure Description

[0041] To make the objectives, technical solutions, and advantages of the invention clearer, the invention will now be described in further detail with reference to the accompanying drawings, wherein:

[0042] Figure 1 This is a flowchart of the cyclotron beam energy coordinated control method of the present invention.

[0043] Figure 2 This is a schematic diagram of the architecture of the cyclotron beam energy cooperative control system of the present invention.

[0044] Figure 3 This is a comparison of the beam energy tracking performance of different controllers under Case 1 of the present invention (10MeV step response).

[0045] Figure 4 This is a comparison of the beam energy tracking performance of different controllers under Case 1 of the present invention (30MeV step response).

[0046] Figure 5 This is a comparison of the beam energy tracking performance of different controllers in Case 2 of the present invention (10MeV step response).

[0047] Figure 6 This is a comparison of the beam energy tracking performance of different controllers in Case 2 of the present invention (30MeV step response). Detailed Implementation

[0048] The technical solutions of some embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments disclosed in the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments disclosed in the present invention are within the scope of protection of the present invention. It should be noted that in the drawings with reference numerals, the same reference numerals and letters represent similar parts. Once a part is defined in a drawing, it will not be defined and explained again in subsequent drawings.

[0049] This invention can be applied to the field of particle accelerator control technology and belongs to the category of industrial process control and automation technology. Specifically, it relates to a cyclotron beam energy collaborative optimization control strategy and system that considers the coupling effect of multiple physical fields (vacuum state, cavity temperature, etc.).

[0050] This invention addresses the technical problems of existing cyclotron control strategies, which often focus on the independent adjustment of a single subsystem. When faced with complex operating condition switching or the superposition of multiple disturbances, these strategies often suffer from long adjustment times, large overshoot, insufficient steady-state accuracy, and limited anti-interference capabilities, making it difficult to meet the extremely high stability requirements of beam energy for high-level BNCT treatment.

[0051] The technical concept of this invention is as follows: During the operation of a cyclotron accelerator, negative hydrogen ions are accelerated along a spiral trajectory under the combined action of a magnetic field and a radio frequency electric field, and finally obtain a beam with the required energy through an extraction system. However, the stability of the beam energy depends not only on the control accuracy of the radio frequency system itself, but also on the coupling influence of the operating states of multiple subsystems such as the vacuum system and the cooling water system. This multi-system coupling characteristic makes beam energy control a complex multivariable, strongly coupled, and nonlinear control problem, and single-loop control methods are difficult to meet the requirements of high-precision and high-stability control. The linear control characteristics of PID control are difficult to cope with the nonlinear dynamics of the system and external disturbances, resulting in problems such as slow response speed, large overshoot, and weak anti-interference ability. Active disturbance rejection control (ADRC), as a novel nonlinear control method, provides an effective way to solve this problem by using an extended state observer to estimate the total disturbance of the system in real time and perform active compensation. However, in practical applications, the estimation accuracy of the extended state observer is limited by the sampling frequency and controller parameter saturation. Especially under high-energy conditions and strong disturbance conditions, the excessive estimation burden of the observer may lead to degradation of control performance.

[0052] Furthermore, beam energy stability is also affected by the output of the vacuum system and cooling water system. Fluctuations in vacuum pressure alter the density of residual gas within the acceleration chamber, causing particle scattering and collisions during acceleration, leading to reduced particle transport efficiency and increased emittance, resulting in a decline in beam quality. Changes in water-cooling temperature affect the geometry of the RF drive cavity and resonant tube through thermal expansion, thereby altering the resonant frequency and phase, ultimately causing beam energy drift. These disturbances mean that the beam energy control system must not only address the dynamic characteristics of the system itself but also resist coupled disturbances from multiple subsystems. However, most existing studies analyze these influencing factors as independent sources of disturbance, lacking a system-level coupled beam energy fluctuation model to describe the dynamic relationship between vacuum pressure, cooling water temperature, and beam energy.

[0053] Based on the above concept, this invention establishes a system-level beam energy fluctuation coupling model. It comprehensively considers the combined effects of combined disturbances on the system-level output, such as vacuum changes caused by beam intensity fluctuations and high-frequency cavity resonant frequency drift caused by cooling water temperature fluctuations. The coupling relationships between system models are integrated, providing a model foundation for multivariable collaborative control. Based on the system-level beam energy fluctuation coupling model, the collaborative control method and system for cyclotron beam energy are optimized and designed, and simulation verification is completed.

[0054] Specifically, the cyclotron beam energy coordinated control method and system disclosed in this invention have the following technical effects:

[0055] 1. The technical solution of this invention can significantly improve the steady-state accuracy and anti-interference capability of beam energy. This invention reveals the multi-physics perturbation path by establishing quantitative coupling relationships such as vacuum pressure-beam intensity and water cooling temperature-high frequency cavity voltage.

[0056] 2. The beam energy control system under the technical solution of this invention possesses excellent dynamic response speed. Due to the introduction of a multivariable feedforward compensation layer, the system can actively cancel out disturbances before they reach the energy output end, exhibiting robustness. The established gain adjustment mechanism allows the IESO to adaptively optimize the observation intensity based on the total disturbance strength. When faced with sudden large disturbances, the system can converge quickly; in the steady-state phase, it can effectively suppress noise amplification from the observer, enhancing the stability of the control system.

[0057] 3. The technical solution of this invention effectively fills the gap in the design and application of advanced control strategies for cyclotron systems. It breaks through the limitations of traditional systems that heavily rely on empirical parameter tuning and model-free PID control, providing theoretical support and technical solutions for the transition of cyclotrons from empirical adjustment to intelligent collaborative control based on mechanistic models.

[0058] In summary, the beam energy synergistic optimization control strategy proposed in this invention can significantly improve the output quality of BNCT core equipment, and has extremely high engineering application value and clinical efficacy guarantee significance.

[0059] To further illustrate the cyclotron beam energy coordinated control method and system provided by the present invention, the following embodiments are disclosed.

[0060] In some embodiments, please refer to Figure 1 This embodiment provides a method for coordinated control of beam energy in a cyclotron, including the following steps:

[0061] S1. Obtain the real-time vacuum pressure fluctuation deviation value and water cooling temperature fluctuation deviation value of the cyclotron system during the current control cycle.

[0062] In some embodiments, in step S1, the vacuum pressure fluctuation deviation value and the water cooling temperature fluctuation deviation value are obtained through the following steps:

[0063] S1.1 Obtain the real-time vacuum pressure, cooling water outlet temperature, and actual beam energy output value in the main control loop of the cyclotron system;

[0064] S1.2 Calculate the vacuum pressure fluctuation deviation value and the water cooling temperature fluctuation deviation value.

[0065] S2. Based on the pre-built cyclotron beam energy fluctuation coupling model, the vacuum pressure fluctuation deviation value and the water cooling temperature fluctuation deviation value of the current control cycle are converted into feedforward compensation control quantities.

[0066] Specifically, the vacuum pressure fluctuation deviation is: ΔP(k) = P(k) − P ref Water cooling temperature fluctuation deviation: ΔT cw (k)=T cw (k)−T ref Among them, P ref and T ref These are the vacuum pressure tracking setting value and the water cooling temperature tracking setting value, respectively.

[0067] In some embodiments, the expression for the cyclotron beam energy fluctuation coupling model is:

[0068] (1)

[0069] In equation (1), Here, k represents the system's nonlinear coefficients, P(t) is the vacuum pressure in Pa, and k is the pressure in Pa. vac Vacuum pressure-energy coupling coefficient, MeV / Pa, T cw (t) represents the water cooling temperature, K; k cwThe water cooling temperature-energy coupling coefficient, MeV / K. Let t be the total system disturbance and t be the sampling time.

[0070] This embodiment establishes a multiphysics coupling model. During accelerator beam propagation, residual gas in the vacuum pipe scatters with high-energy particles, leading to particle energy loss. Simultaneously, temperature fluctuations in the water-cooling system alter the resonant frequency through the thermal expansion of the accelerator cavity, thus affecting the energy gain of the particles. These two physical effects have clear transmission mechanisms and measurable coupling paths, providing a theoretical basis for establishing a quantitative coupling model.

[0071] In some embodiments, the feedforward compensation control quantity The calculation formula is:

[0072] (2)

[0073] In equation (2), b0 is the nominal control input gain, and k vac Let k be the coupling transfer coefficient between vacuum pressure and beam energy fluctuations. cw The water cooling temperature-energy coupling coefficient, This represents the deviation value of vacuum pressure fluctuation. This represents the deviation value of water cooling temperature fluctuation.

[0074] Specifically, the coupling transfer coefficient k vac and k cw It is obtained through offline system identification of actual cyclotron multiphysics operation data or derivation based on mechanistic models.

[0075] This embodiment provides a feedforward control law based on a multi-physics field coupled dynamic model. By using a preset coupling transfer coefficient, the real-time collected vacuum pressure deviation and water cooling temperature deviation are directly converted into feedforward compensation control quantities, thereby achieving active cancellation before disturbances affect the beam energy.

[0076] S3. Obtain the tracking deviation between the target reference input and the observed state in the current control cycle, as well as the actual beam energy output value in the main control loop of the current control cycle, to obtain the adaptive gain of the nonlinear state error feedback, and then obtain the nonlinear feedback control quantity.

[0077] In some embodiments, step S3 specifically includes the following steps:

[0078] S3.1 Obtain the observation error and the actual beam energy output value in the main control loop under the observation state, and obtain the total disturbance estimate based on the observation error and the actual beam energy output value;

[0079] S3.2. Based on the total disturbance estimate, obtain the adaptive gain of the nonlinear state error feedback;

[0080] S3.3 Obtain the tracking deviation values ​​of the target reference input and the observation state respectively, and combine them with the adaptive gain to obtain the nonlinear feedback control quantity.

[0081] Specifically, nonlinear functions are used for state tracking and total perturbation estimation. The state update equation is as follows:

[0082] (3)

[0083] In equation (3), h is the integration step size, z1 is the tracking state of the system output, z2 is the differential state of the output, z3 is the estimated state of the unmodeled internal dynamics and the total external disturbance, b0 is the nominal control input gain, and β1, β2, and β3 are the base gains of the IESO adaptive observation module; a e α is the compensation coefficient; fal is a nonlinear continuous function; α1 and α2 are nonlinear factors; and δ is the limit of the linear region width.

[0084] In some embodiments, the nonlinear feedback control quantity The expression is:

[0085] (4)

[0086] In equation (4), For adaptive gain, α3 and α4 are the corresponding feedback nonlinearity factors. is a nonlinear function, where e is the error, α1 is the nonlinear factor, and δ is the limit of the linear region width.

[0087] Specifically, the gain saturation limit is: , For nominal gain, ω c This refers to the controller bandwidth.

[0088] Specifically, adaptive gain β 01 (k) and β 02 The formula for calculating (k) is:

[0089] (5)

[0090] In equation (5), β 01 nom and β 02 nom γ1 and γ2 are the nominal control gain, and d is the adaptive adjustment factor. nom The nominal disturbance threshold. This is the total disturbance estimate. This mechanism ensures that the gain is increased under strong transient disturbances to improve the disturbance rejection response, and the gain is decreased to suppress high-frequency flutter when approaching steady state.

[0091] Specifically, the nonlinear function fal is defined as:

[0092] , where e is the error, α1 is the nonlinear factor, and δ is the limit of the linear region width.

[0093] In some embodiments, the nonlinear function fal(e,α,δ) is a saturated nonlinear function, and its expression is smoothly switched according to the linear or nonlinear region where the error e is located, so as to avoid the system chattering phenomenon caused by traditional sign functions.

[0094] S4. The feedforward compensation control quantity and the nonlinear feedback control quantity of the current control cycle are superimposed to obtain the final control command.

[0095] In some embodiments, the final control command is obtained through a final control law, and the expression of the final control law is:

[0096] (6)

[0097] In equation (6), For the first Feedforward compensation amount per control cycle For the first The nonlinear feedback control quantity for each control cycle, b0 is the nominal control input gain, and k vac Let k be the vacuum pressure-energy coupling coefficient. cw The water cooling temperature-energy coupling coefficient, This represents the deviation value of vacuum pressure fluctuation. This represents the deviation value of water cooling temperature fluctuation. It is a nonlinear feedback control quantity. This is the estimated total disturbance.

[0098] This control law enables a deep synergy between feedforward pre-compensation for measurable disturbances based on prior models and active feedback suppression of unknown residual disturbances.

[0099] S5. The final control command is converted into an analog voltage signal and output to the beam energy control actuator of the cyclotron to operate the actuator.

[0100] Specifically, the beam energy control actuator includes a DC servo motor in the beam extraction system. The operation of the DC servo motor can cause a change in the probe position, and different probe positions result in different output beam energy. In this embodiment, converting the final control command into an analog voltage signal and outputting it to the beam energy control actuator of the cyclotron means issuing a control command to the DC servo motor in the beam extraction system to adjust the probe position, thereby adjusting the beam energy.

[0101] S6. Enter the next control cycle and repeat steps S1 to S5 to achieve dynamic adjustment of the cyclotron beam energy and achieve closed-loop stable adjustment of energy fluctuations.

[0102] Specifically, if the above methods are implemented in the form of software functional modules, they can be stored in computer-readable storage media, which facilitates system upgrades and functional expansion.

[0103] In some embodiments, a cyclotron beam energy coordinated control system is also provided for implementing the cyclotron beam energy coordinated control method as described above, including:

[0104] The system parameter acquisition unit is used to acquire the cyclotron system state parameters for the corresponding control cycle. The cyclotron system state parameters include: real-time vacuum pressure fluctuation deviation value and water cooling temperature fluctuation deviation value, tracking deviation value between target reference input and observation state, and actual beam energy output value in the main control loop.

[0105] The multivariable feedforward compensation control quantity calculation unit is used to convert the vacuum pressure fluctuation deviation value and the water cooling temperature fluctuation deviation value of the corresponding control cycle into feedforward compensation control quantity based on the pre-built cyclotron beam energy fluctuation coupling model, so as to achieve pre-compensation before the disturbance affects the beam energy.

[0106] The nonlinear feedback control quantity calculation unit is used to obtain the adaptive gain of the nonlinear state error feedback based on the tracking deviation value between the target reference input and the observed state in the corresponding control cycle, and the actual beam energy output value in the main control loop in the corresponding control cycle, thereby obtaining the nonlinear feedback control quantity. The nonlinear feedback control quantity calculation unit can independently process the error using dual-band (high / low frequency) nonlinear functions, estimate the internal state trajectory and total internal and external coupling disturbances of the system in real time, and dynamically output the adaptive gain; and calculate the nonlinear error feedback quantity based on the target deviation and the adaptive gain.

[0107] The collaborative control command synthesis unit is used to superimpose the feedforward compensation control quantity and the nonlinear feedback control quantity of the corresponding control cycle to obtain the final control command, and convert the final control command into an analog voltage signal, which is then output to the beam energy control actuator of the cyclotron to operate the actuator.

[0108] The cyclotron beam energy coordinated control system provided in this embodiment has a composite control architecture. The multivariable feedforward compensation control for vacuum pressure and water cooling temperature and the nonlinear feedback control for beam energy are respectively set as the feedforward layer and the feedback layer, forming a coordinated control architecture that can advance the cancellation of external disturbances and suppress the closed loop of internal unknown disturbances.

[0109] In some embodiments, the system parameter acquisition unit simultaneously stores the ideal operating reference value of the auxiliary system, namely the vacuum pressure setpoint P. ref and water cooling temperature setting value T ref .

[0110] In some embodiments, the multivariable feedforward compensation control quantity calculation unit further includes a multivariable coupling deviation calculation module, used to calculate the real-time state fluctuation deviation of the auxiliary system caused by the multi-physics field coupling effect; correspondingly, the system parameter acquisition module acquires the real-time vacuum pressure value and water cooling temperature value, and calculates the real-time vacuum pressure fluctuation deviation value and water cooling temperature fluctuation deviation value in the multivariable coupling deviation calculation module.

[0111] Specifically, the vacuum pressure fluctuation deviation is: ΔP(k) = P(k) − P ref Water cooling temperature fluctuation deviation: ΔT cw (k)=T cw (k)−T ref P ref and T ref These are the vacuum pressure tracking setting value and the water cooling temperature tracking setting value, respectively.

[0112] In some embodiments, the nonlinear feedback control quantity calculation unit includes an IESO adaptive observation module and an ANLSEF feedback adjustment module;

[0113] The IESO adaptive observation module is used to acquire the observation error and the actual beam energy output value in the main control loop under the observation state, and to obtain the total disturbance estimate based on the observation error e(k)=z1(k)−y(k) and the actual beam energy output value; and to dynamically adjust the adaptive gain β of the nonlinear state error feedback based on the total disturbance estimate z3(k) of the current period and its absolute amplitude. 01 (k) and β 02(k). In this embodiment, a dynamic gain adjustment algorithm is introduced into the IESO adaptive observation module, which enables the system to dynamically scale the observation gain in real time according to the absolute magnitude of the total disturbance estimate. This solves the contradiction between fast tracking and steady-state noise immunity when fixed gain is difficult to balance, and improves the robustness and adaptability of the system.

[0114] In some embodiments, the nonlinear function fal(e,α,δ) is a saturated nonlinear function, and its expression is smoothly switched according to the linear or nonlinear region where the error e is located, so as to avoid the system chattering phenomenon caused by traditional sign functions.

[0115] Preferably, a low-frequency tracking function fal is used. LF and high-frequency tracking function fal HF and the corresponding gain β 3L β 3H Errors are processed by frequency band division to achieve accurate observation of complex disturbances over a wide frequency band.

[0116] The ANLSEF feedback adjustment module is used to generate a nonlinear feedback control quantity u0(k) based on the tracking deviations e1(k) and e2(k) between the target reference input and the observation state, combined with the adaptive gain obtained by the adaptive feedback gain dynamic adjustment module.

[0117] Specifically, the functional modules can be integrated into an industrial control computer or a distributed control architecture can be adopted, with the modules communicating with each other via an industrial bus.

[0118] In practice, the final synthesized digital control command u(k) is converted into an analog voltage signal via a DA converter and output to the beam energy control actuator of the cyclotron to drive the actuator to move, thereby achieving closed-loop stable regulation of energy fluctuations.

[0119] In some embodiments, this embodiment employs the aforementioned cyclotron beam energy coordinated control system to simulate and verify the cyclotron beam energy coordinated control method. The simulation process is based on a complete system coupled model, including a vacuum pressure subsystem, a water-cooled temperature subsystem, and a beam energy system, revealing the impact of multivariable coupled disturbances on beam energy control. This embodiment's simulation is implemented on the Matlab & Simulink platform, setting PID, ADRC, and FM-ADRC (designed in Section 6.3) control strategies for performance reference comparison. The simulation step size is uniformly set to 0.02s, and the model is solved using a fourth-order Runge-Kutta method.

[0120] This embodiment focuses on the performance of the cyclotron beam energy coordinated control system under an energy fluctuation coupling model. Therefore, the step change in the beam setpoint occurs after the vacuum pressure and water-cooling temperature subsystems have stably tracked the setpoint under their respective control strategies. For the vacuum water-cooling subsystem, the setpoint in this embodiment is set as follows:

[0121] ;

[0122] Based on the assumption that the subsystem output is stabilizing, two sets of settings for beam energy control were set as follows:

[0123] Set Point 1: ;

[0124] Set Point 2: .

[0125] This embodiment sets up two cases based on two sets of beam energy control setpoints. Case 1 uses these two setpoints for simulation testing. The vacuum pressure and water-cooling temperature subsystems are only subject to ±1% random fluctuations under normal operating conditions. The feedforward compensation model is accurate with no parameter errors, and no additional measurement noise is introduced. Case 2 builds upon Case 1 by superimposing multiple perturbations to simulate the harsh conditions of actual accelerator operation. Specifically, a perturbation with an amplitude of 0.3 × 10⁻⁶ is superimposed on the vacuum pressure subsystem. -6 The periodic leakage disturbance of Pa is superimposed on the water-cooled temperature subsystem with a periodic temperature fluctuation of 0.5℃. Due to the uncertainty of the superposition model, considering the error of the coupling coefficient in the actual system, the feedforward compensation coefficient used by the controller is set to a deviation of ±5%. Gaussian noise with an amplitude of 0.15MeV is introduced into the beam energy system to simulate unknown disturbances such as unmodeled magnetic field fluctuations and measurement noise.

[0126] Simulation results are as follows Figures 3 to 6 As shown, the performance indicators of each controller were calculated and analyzed using a 30MeV step response, which has a larger error amplitude and can more significantly observe the differences in controller performance. In this embodiment, IAE, ISE, and ITAE indicators were selected for performance evaluation: IAE reflects the overall control accuracy of the beam energy; the squared weighted term in the ISE indicator facilitates the analysis of system stability; and ITAE reflects the response characteristics and long-term performance of energy tracking, comprehensively reflecting the fast and accurate response during energy switching. Tables 1 and 2 present the comparison results of the IAE, ISE, and ITAE performance indicators of the four controllers for beam energy error tracking under two case scenarios.

[0127] Table 1. Performance indicators of the controller beam energy tracking at a setpoint of 30 MeV in Case 1

[0128] Control strategy IAE ISE ITAE PID 1.8470 5.0754 12.0378 ADRC 1.5230 1.3690 3.0042 FM-ADRC 1.1860 0.4839 1.2081 Technical solution of this embodiment 0.8940 0.3215 0.7850

[0129] The simulation results show that for the energy tracking process of the integrated beam energy coupling model, all four control strategies can eventually stabilize the system at the set value of 30 MeV, but there are significant differences in the dynamic response characteristics. Figure 3 The beam energy response curves of the four controllers in Case 1 are shown. The PID and ADRC strategies, due to insufficient utilization of system model information, exhibit large overshoot and long settling times when the setpoint changes abruptly. In contrast, while the FM-ADRC control incorporates a mathematical model of the beam energy system to calculate the feedforward, improving response speed and overshoot suppression to some extent, this strategy only considers the dynamic model of the beam energy system itself and does not incorporate the coupling influence mechanism of the vacuum system and water cooling system on the beam energy revealed by the beam energy fluctuation coupling model. Therefore, when beam intensity fluctuations cause changes in vacuum level, or cooling water temperature fluctuations cause high-frequency cavity resonant frequency drift, the model feedforward of the FM-ADRC strategy cannot accurately predict the combined impact of these coupled disturbances on the beam energy, resulting in a settling process that still requires approximately 90 ms to reach steady state, and the overshoot remains around 0.8 MeV. The technical solution strategy in this embodiment fully utilizes the precise description of the multi-physics coupling relationships, such as vacuum pressure, cooling water temperature, high-frequency cavity voltage, and magnet excitation current, in the beam energy fluctuation coupling model. Through a multivariable feedforward compensation mechanism, it can accurately calculate the combined effect of these key parameters on the beam energy based on real-time measurements, and apply corresponding compensation control quantities before the disturbance is transmitted to the beam energy. This multi-source disturbance collaborative compensation based on the coupling model reduces the settling time of the technical solution strategy in this embodiment by approximately 22% to 70 ms and reduces the overshoot by approximately 37.5% to 0.5 MeV, exhibiting better control performance.

[0130] Figures 5 to 6This paper compares the disturbance rejection performance of four control strategies after introducing superimposed disturbances in Case 2. It can be seen that when the system is operating at a steady state of 30 MeV and subjected to a continuous disturbance of ±2% beam intensity fluctuation, both the PID and ADRC strategies exhibit significant energy fluctuations due to a lack of accurate modeling of the disturbance propagation mechanism. The PID controller shows a beam energy fluctuation amplitude of ±0.3 MeV, while the ADRC strategy, although achieving some suppression through a disturbance observer, still shows a fluctuation amplitude of around ±0.2 MeV. The FM-ADRC strategy, by using a feedforward beam energy system model, reduces the fluctuation amplitude to ±0.1 MeV, demonstrating good disturbance rejection capability. The technical solution in this embodiment fully leverages the advantages of the beam energy fluctuation coupling model. By accurately predicting the combined effects of vacuum changes caused by beam intensity fluctuations, high-frequency cavity load fluctuations, and magnet excitation current disturbances on beam energy, it achieves coordinated feedforward compensation for multi-source disturbances, controlling the beam energy fluctuation amplitude within ±0.05 MeV, a further 50% reduction compared to the FM-ADRC strategy. Figure 6 The 30 MeV magnified view more clearly shows that the strategy of this embodiment maintains almost steady-state accuracy under disturbances, while other strategies exhibit varying degrees of oscillation and deviation. The quantitative comparison of performance indicators in Table 2 further verifies this conclusion. The IAE value of the strategy of this embodiment is 1.2150, which is reduced by 54.7%, 43.1%, and 25.4% compared to PID, ADRC, and FM-ADRC, respectively. The ISE value is further reduced by 93.7%, 80.0%, and 41.8%, fully demonstrating the significant advantage of the multivariate feedforward compensation mechanism based on the coupled model in suppressing complex disturbances.

[0131] Table 2. Performance indicators of the controller beam energy tracking at a setpoint of 30 MeV in Case 2

[0132] Control strategy IAE ISE ITAE PID 2.6840 7.8520 18.5470 ADRC 2.1350 2.4580 5.2180 FM-ADRC 1.6280 0.8450 2.0340 Technical solution of this embodiment 1.2150 0.4920 1.1580

[0133] The technical solution adopted in this embodiment designs a multivariable feedforward compensation control law, which predicts coupled disturbances based on the real-time measured values ​​of the subsystem output. Simulation results show that the overshoot of the control method of this invention is only 0.5 MeV, the settling time is shortened to 70 ms, the steady-state error is controlled within ±0.01 MeV, and the IAE, ISE, ITAE, and ITSE are reduced by 25.4%, 41.8%, 18.6%, and 35.2%, respectively, fully verifying the significant advantages of the cyclotron beam energy cooperative control method.

[0134] In some embodiments, an electronic device is also provided, including a processor and a memory, the processor being coupled to the memory; the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory to implement the cyclotron beam energy cooperative control method as described above.

[0135] In some embodiments, a computer-readable storage medium is also provided for storing a computer program that is executed by a processor to implement the cyclotron beam energy cooperative control method as described above.

[0136] In the description disclosed in this invention, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to has a specific orientation, or is constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the disclosure of this invention.

[0137] Unless the context otherwise requires, throughout the specification and claims, the term "comprising" is interpreted as open-ended and encompassing, meaning "including, but not limited to." In the description, terms such as "one embodiment," "some embodiments," "exemplary embodiment," "exemplary," or "some examples" are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example disclosed in the invention. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics mentioned may be included in any suitable manner in any one or more embodiments or examples.

[0138] The terms "first" and "second" are used merely to distinguish different descriptive objects and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated; that is, they do not limit the position, order, priority, quantity, or content of the described objects. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the embodiments disclosed in this invention, unless otherwise stated, "a plurality of" means two or more.

[0139] In describing some embodiments, the term "connection" and its derivative expressions may be used. For example, the term "connection" may be used in describing some embodiments to indicate that two or more components have direct physical or electrical contact with each other. The embodiments disclosed herein are not necessarily limited to the content of this document.

[0140] "At least one of A, B, and C" has the same meaning as "at least one of A, B, or C," both including the following combinations of A, B, and C: only A, only B, only C, a combination of A and B, a combination of A and C, a combination of B and C, and a combination of A, B, and C. In the description of the embodiments of this application, unless otherwise stated, " / " means "or," for example, A / B can mean A or B; "A and / or B" includes the following three combinations: only A, only B, and a combination of A and B.

[0141] The use of “configured as” in this article implies an open and inclusive language that does not exclude the applicability to or configuration of devices to perform additional tasks or steps.

[0142] In addition, the use of “based on” implies openness and inclusivity, because processes, steps, calculations or other actions “based on” one or more of the stated conditions or values ​​may in practice be based on additional conditions or values ​​beyond those stated.

[0143] As used herein, “about” and “approximately” include the values ​​stated and the average values ​​within an acceptable range of deviation from a particular value, wherein the acceptable range of deviation is determined by a person skilled in the art taking into account the measurement under discussion and the error associated with the measurement of the particular quantity (i.e., the limitations of the measurement system).

[0144] This document describes exemplary embodiments with reference to cross-sectional views and / or plan views, which are idealized exemplary drawings. In the drawings, the thickness of layers and regions is enlarged for clarity. Therefore, variations in shape relative to the drawings are contemplated due to, for example, manufacturing techniques and / or tolerances. Thus, exemplary embodiments should not be construed as limited to the shapes of the regions shown herein, but rather include shape deviations due to, for example, manufacturing processes. For example, etched regions shown as rectangular would typically have curved features. Therefore, the regions shown in the drawings are schematic in nature, and their shapes are not intended to show the actual shapes of the regions of the device, nor are they intended to limit the scope of the exemplary embodiments.

[0145] The above description is merely a specific embodiment of the present invention, but the scope of protection disclosed in the present invention is not limited thereto. Any variations or substitutions conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection disclosed in the present invention. Therefore, the scope of protection disclosed in the present invention should be determined by the scope of the claims.

Claims

1. A method for coordinated control of beam energy in a cyclotron accelerator, characterized in that, Includes the following steps: S1. Obtain the real-time vacuum pressure fluctuation deviation value and water cooling temperature fluctuation deviation value of the cyclotron system in the current control cycle. S2. Based on the pre-built cyclotron beam energy fluctuation coupling model, the vacuum pressure fluctuation deviation value and the water cooling temperature fluctuation deviation value in the current control cycle are converted into feedforward compensation control quantities. S3. Obtain the tracking deviation between the target reference input and the observed state in the current control cycle, as well as the actual beam energy output value in the main control loop of the current control cycle, to obtain the adaptive gain of the nonlinear state error feedback, and then obtain the nonlinear feedback control quantity. S4. The feedforward compensation control quantity and the nonlinear feedback control quantity of the current control cycle are superimposed to obtain the final control command; S5. Convert the final control command into an analog voltage signal and output it to the beam energy control actuator of the cyclotron to operate the actuator; S6. Enter the next control cycle and repeat steps S1 to S5 to achieve dynamic adjustment of the cyclotron beam energy.

2. The method for coordinated control of beam energy in a cyclotron accelerator according to claim 1, characterized in that, In step S1, the vacuum pressure fluctuation deviation value and the water cooling temperature fluctuation deviation value are obtained through the following steps: S1.1 Obtain the real-time vacuum pressure, cooling water outlet temperature, and actual beam energy output value in the main control loop of the cyclotron system; S1.2 Calculate the vacuum pressure fluctuation deviation value and the water cooling temperature fluctuation deviation value.

3. The method for coordinated control of beam energy in a cyclotron accelerator according to claim 1, characterized in that, The expression for the cyclotron beam energy fluctuation coupling model is as follows: ； In the formula, Here, k represents the system's nonlinear coefficients, P(t) is the vacuum pressure in Pa, and k is the pressure in Pa. vac Vacuum pressure-energy coupling coefficient, MeV / Pa, T cw (t) represents the water cooling temperature, K; k cw The water cooling temperature-energy coupling coefficient, MeV / K. Let t be the total system disturbance and t be the sampling time.

4. The method for coordinated control of beam energy in a cyclotron accelerator according to claim 1, characterized in that, Step S3 specifically includes the following steps: S3.1 Obtain the observation error and the actual beam energy output value in the main control loop under the observation state, and obtain the total disturbance estimate based on the observation error and the actual beam energy output value; S3.

2. Based on the total disturbance estimate, obtain the adaptive gain of the nonlinear state error feedback; S3.3 Obtain the tracking deviation values ​​of the target reference input and the observation state respectively, and combine them with the adaptive gain to obtain the nonlinear feedback control quantity.

5. The method for coordinated control of beam energy in a cyclotron accelerator according to claim 1 or 3, characterized in that, The formula for calculating the feedforward compensation control quantity is as follows: ； In the formula, b0 is the nominal control input gain, k vac Let k be the coupling transfer coefficient between vacuum pressure and beam energy fluctuations. cw The water cooling temperature-energy coupling coefficient, This represents the deviation value of vacuum pressure fluctuation. This represents the deviation value of water cooling temperature fluctuation.

6. The method for coordinated control of beam energy in a cyclotron accelerator according to claim 1 or 4, characterized in that, The expression for the nonlinear feedback control quantity is: ； In the formula, For adaptive gain, α3 and α4 are the corresponding feedback nonlinearity factors. is a nonlinear function, where e is the error, α1 is the nonlinear factor, and δ is the limit of the linear region width.

7. The method for coordinated control of beam energy in a cyclotron accelerator according to claim 1, characterized in that, The final control command is obtained through a final control law, and the expression of the final control law is: ； In the formula, For the first Feedforward compensation amount per control cycle For the first The nonlinear feedback control quantity for each control cycle, b0 is the nominal control input gain, and k vac Let k be the vacuum pressure-energy coupling coefficient. cw The water cooling temperature-energy coupling coefficient, This represents the deviation value of vacuum pressure fluctuation. This represents the deviation value of water cooling temperature fluctuation. It is a nonlinear feedback control quantity. This is the estimated total disturbance.

8. A cyclotron beam energy coordinated control system, used to implement the cyclotron beam energy coordinated control method as described in claim 1, characterized in that, include: The system parameter acquisition unit is used to acquire the real-time vacuum pressure fluctuation deviation value and water cooling temperature fluctuation deviation value of the cyclotron system for the corresponding control cycle, the tracking deviation value between the target reference input and the observation state, and the actual beam energy output value in the main control loop. The multivariable feedforward compensation control quantity calculation unit is used to convert the vacuum pressure fluctuation deviation value and the water cooling temperature fluctuation deviation value of the corresponding control cycle into feedforward compensation control quantity based on the pre-built cyclotron beam energy fluctuation coupling model. The nonlinear feedback control quantity calculation unit is used to obtain the adaptive gain of the nonlinear state error feedback based on the tracking deviation value between the target reference input and the observed state in the corresponding control cycle, and the actual beam energy output value in the main control loop in the corresponding control cycle, and then obtain the nonlinear feedback control quantity. The collaborative control command synthesis unit is used to superimpose the feedforward compensation control quantity and the nonlinear feedback control quantity of the corresponding control cycle to obtain the final control command, and convert the final control command into an analog voltage signal, which is then output to the beam energy control actuator of the cyclotron to operate the actuator.

9. An electronic device, characterized in that, Includes a processor and a memory, wherein the processor is coupled to the memory; The memory is used to store computer programs, and the processor is used to execute the computer programs stored in the memory to implement the cyclotron beam energy coordinated control method as described in any one of claims 1 to 7.

10. A computer-readable storage medium for storing computer programs, characterized in that, The computer program is executed by a processor to implement the cyclotron beam energy cooperative control method as described in any one of claims 1 to 7.

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