Failure compensation-matching method and system for high-current superconducting proton linear accelerator

Abstract

The invention provides a high-current superconducting proton linear accelerator failure compensation-matching method and system, and belongs to the technical field of particle accelerators, and the method comprises the following steps: a fault detection step: determining the position and failure degree of a failed superconducting radio frequency cavity; a phase shift compensation step: adjusting radio frequency parameters of the working cavity in the period of the failure cavity through analytical calculation so as to recover longitudinal phase shift; an envelope matching step: optimizing matching cavity parameters in a downstream local range of the failure cavity to minimize a matching error between a beam longitudinal envelope and a design envelope; and an energy compensation step, in which compensation cavity parameters are adjusted under constraint conditions to recover total beam energy, and a corresponding system comprises a fault detection module, a core processing module, a parameter output module, a verification feedback module and the like. According to the method, a complex multi-target recovery problem is decomposed into a three-step collaborative recovery strategy of phase shift compensation, envelope matching and energy compensation, the recovery time is shortened to several minutes, and high-precision collaborative rapid recovery of beam energy, energy dispersion and emittance is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of particle accelerators, in particular to a failure compensation-matching method and system for a high-current superconducting proton linear accelerator. BACKGROUND

[0002] As a core device for basic scientific research and many high-tech applications, particle accelerators play an irreplaceable role in the fields of energy, medicine, material science, etc. High-current proton linear accelerators use superconducting radio frequency cavities (SRF cavities) to achieve efficient acceleration, which can accelerate the proton beam to high energy and provide key support for national major scientific infrastructure such as spallation neutron sources and accelerator-driven subcritical systems (ADS).

[0003] However, superconducting radio frequency cavities face many challenges during operation, and may experience performance degradation or even complete failure due to superconducting loss, microphonic vibration, mechanical vibration, vacuum leakage, etc. Once the superconducting radio frequency cavity fails, it will directly lead to a decrease in beam energy, and destroy the longitudinal phase space structure of the beam, causing the key parameters such as beam emittance and energy spread to deteriorate. For example, the decrease in beam energy will affect the injection efficiency of downstream devices, the increase in energy spread may lead to loss of control of the beam in the subsequent transmission process, and the increase in emittance means that the beam quality has decreased and cannot meet the needs of high-precision experiments and production.

[0004] Currently, there are two main types of recovery methods for superconducting radio frequency cavity failures. The first type is a lookup table method that pre-stores single fault compensation parameters. This method pre-stores compensation parameters for possible fault conditions, and directly calls them when a fault occurs. However, this method has poor flexibility, as the actual operation has complex and diverse fault conditions, and the pre-stored parameters are difficult to cover all possible fault modes, making it difficult to effectively deal with complex faults. The second type is an online optimization method based on intelligent algorithms such as genetic algorithms. This type of method has strong adaptability and can optimize in real time according to actual fault conditions. However, due to the complexity of the accelerator system model, the huge search space, and the strong nonlinearity of the model, the calculation time is extremely long, usually more than an hour. During the operation of the spallation neutron source, the beam parameters need to be quickly recovered within minutes to meet the requirements of real-time and stability, so the traditional online optimization method cannot meet the engineering requirements.

[0005] In addition, most existing methods focus on restoring the central energy of the beam, and lack effective solutions for the coordinated recovery of multiple parameters such as longitudinal emittance and energy spread. In actual operation, multiple parameters of the beam are interrelated, and only restoring the central energy cannot guarantee the overall quality of the beam, which may still not meet the requirements of downstream devices in other aspects.

[0006] Therefore, it has important practical significance to develop a superconducting proton linear accelerator failure compensation method and system which has fast calculation speed, can cooperatively recover multiple beam parameters, and can adapt to single-cavity and multi-cavity complex failure scenarios. SUMMARY

[0007] In view of the above problems, the application aims to provide a high-current superconducting proton linear accelerator failure compensation-matching algorithm and system, which is especially suitable for the scene of partially or completely failed superconducting radio frequency cavities, and can quickly and accurately recover key parameters such as beam energy, energy spread and emittance through intelligent compensation technology. Through the three-step cooperative strategy (phase shift compensation, envelope matching and energy compensation) of analytical calculation combined with local optimization, the traditional hour-level recovery time is shortened to several minutes, which significantly improves the reliability and availability of the accelerator, and meets the stringent requirements of particle physics research, isotope production and other national major needs for high-precision beam parameters The technical scheme adopted by the application is: a high-current superconducting proton linear accelerator failure compensation-matching method, comprising the following steps: Fault detection step: determining the position and failure degree of the superconducting radio frequency cavity with performance degradation or failure; Phase shift compensation step: based on the beam longitudinal transmission model, adjusting the radio frequency parameters of one or more working cavities in the acceleration period of the failed cavity through analytical calculation, so that the longitudinal phase shift of the period is restored to the design value; Envelope matching step: in at least one acceleration period downstream of the failed cavity, the radio frequency parameters of one or more matching cavities are optimized to minimize the matching error between the beam longitudinal envelope and the design envelope trajectory; Energy compensation step: under the constraint condition of keeping the bunching intensity of one or more compensation cavities unchanged, adjusting the electric field intensity and synchronous phase of the compensation cavity to restore the total beam energy to the design value.

[0008] Preferably, in the phase shift compensation step, if the failed cavity is partially failed, the phase shift is restored by adjusting its own synchronous phase; if the failed cavity is completely failed, the total phase shift of the period is cooperatively restored by optimizing the radio frequency parameters of other working cavities in the same period.

[0009] Preferably, the envelope matching step uses a genetic algorithm for optimization, and the objective function of optimization is the root mean square error between the beam longitudinal RMS envelope and the design envelope at the selected position from upstream to downstream of the failed cavity.

[0010] Preferably, the energy compensation step provides at least two strategies: Local compensation strategy: significantly increasing the electric field intensity on a few cavities adjacent to the failed cavity to quickly restore the energy; Global compensation strategy: uniformly fine-tune the electric field intensity of multiple cavities throughout the entire acceleration section containing the failed cavity to make the system parameter changes as smooth as possible.

[0011] Preferably, in the energy compensation step, the bisection method is used to iteratively solve the uniform electric field amplification coefficient or cavity field intensity adjustment amount that meets the energy recovery target.

[0012] A high-current superconducting proton linear accelerator failure compensation-matching system, comprising: A fault detection and input module for real-time monitoring or receiving fault information of superconducting cavities; A PEE algorithm core processing module connected to the fault detection and input module, including a phase shift compensation unit, an envelope matching unit and an energy compensation unit executed in turn; A parameter output and execution module for outputting the RF parameter set calculated by the core processing module to the accelerator low-level control system.

[0013] Preferably, a high-current superconducting proton linear accelerator failure compensation-matching system further comprises a verification and feedback module for verifying the recovery effect according to the feedback data of the beam diagnosis equipment and triggering the necessary re-optimization.

[0014] Preferably, the fault detection and input module communicates with the database through the accelerator control network, and the parameter configuration file generated by the parameter output and execution module can directly drive the low-level control system to update the cavity parameters.

[0015] Preferably, the phase shift compensation, envelope matching and energy compensation steps decouple the complex recovery problem, combine analytical methods with local optimization, and shorten the calculation time from hours to within ten minutes, achieving high-precision collaborative recovery of beam energy, energy spread and emittance.

[0016] Preferably, a high-current superconducting proton linear accelerator failure compensation-matching system can automatically perform the steps of a high-current superconducting proton linear accelerator failure compensation-matching method, and the system significantly improves the reliability and availability of the accelerator operation, and the recovery calculation time is shortened to within ten minutes.

[0017] Compared with the prior art, the present application has the following significant advantages: The present application decomposes the complex multi-target recovery problem into three steps of phase shift compensation, envelope matching and energy compensation, and uses a large number of analytical calculations. In the phase shift compensation step, the cavity parameters in the failure period are adjusted by analytical calculation based on the beam longitudinal transport model, which can quickly recover the longitudinal focusing phase shift; the envelope matching step uses genetic algorithm for local optimization, which reduces the search space; the energy compensation step uses the bisection method to improve the calculation efficiency. Overall, the recovery time is shortened from hours to less than 10 minutes by using the traditional genetic algorithm with multi-particle simulation, which meets the engineering demand of minute-level fast recovery of strong current accelerator running, and realizes online real-time fault-tolerant operation.

[0018] The present application not only focuses on the recovery of the beam center energy, but also pays attention to the coordinated recovery of multiple parameters such as longitudinal emittance and energy spread. The phase shift compensation step effectively suppresses the growth of beam longitudinal emittance, and by recovering the longitudinal focusing phase shift, the focusing effect of the beam in the longitudinal direction is ensured; the envelope matching step optimizes the matching cavity parameters in the local range downstream of the failure point, so that the beam envelope matches the design trajectory, stabilizes the energy spread, and suppresses the energy spread oscillation; the energy compensation step accurately adjusts the electric field and phase under the constraint of keeping the bunching intensity of each compensation cavity unchanged, and recovers the total energy of the beam. The three steps work together to ensure the comprehensive quality of the beam and meet the stringent requirements of the spallation neutron source device on the injected beam.

[0019] The present application can effectively handle various fault modes such as single-cavity complete / partial failure and multi-cavity failure. In the phase shift compensation step, different situations (partial failure or complete failure) of the failed cavity are handled by adjusting its own synchronization phase or optimizing the radio frequency parameters of other working cavities in the same period; the energy compensation step provides two strategies of local compensation and global compensation, the local compensation strategy can quickly recover the energy in a few cavities adjacent to the failed cavity, which is suitable for scenes with strict recovery time requirements, and the global compensation strategy uniformly fine-tunes the electric field intensity of multiple cavities in the entire acceleration section containing the failed cavity, making the system parameter change the smoothest, which is suitable for scenes with high system stability requirements. Users can flexibly choose the compensation strategy according to the running preferences and hardware limitations of different accelerators, improving the adaptability and robustness of the system.

[0020] The method and system of the present application have been verified by large-scale numerical simulation and real beam experiment. Especially in the simulation environment and actual operation of CSNS-II superconducting linear accelerator, good results have been achieved, which can be directly integrated into the existing accelerator control system to realize automatic intelligent fault-tolerant operation without large-scale modification of the existing system, reducing the application cost and having wide engineering application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1is the overall architecture and workflow of the PEE algorithm system of the application, including fault detection, phase shift compensation, envelope matching, energy compensation and verification feedback modules.

[0022] Figure 2 is the principle diagram of the phase shift compensation module in the application, which illustrates how to restore the longitudinal focusing phase shift by adjusting the cavity parameters.

[0023] Figure 3 is the envelope matching optimization process diagram in the application, which shows the process of genetic algorithm optimizing matching cavity parameters in a local range.

[0024] Figure 4 is the energy compensation cavity grabbing diagram in the application, which shows the implementation position of the local compensation strategy.

[0025] Figure 5 is the comparison diagram of the emittance of the embodiment of the application before and after the failure compensation of the CSNS-II superconducting cavity, which directly shows the change of the beam emittance before and after the compensation.

[0026] Figure 6 is the longitudinal envelope comparison diagram of the embodiment of the application before and after the failure compensation of the CSNS-II superconducting cavity, which shows the recovery of the beam longitudinal envelope before and after the compensation.

[0027] Figure 7 is the comparison diagram of the global compensation and local compensation electric field settings of the embodiment of the application after the failure compensation of the CSNS-II superconducting cavity, which compares the differences in electric field intensity settings between the global compensation and the local compensation strategies.

[0028] Figure 8 is the local compensation beam energy deviation from the design value diagram of the embodiment of the application after the failure compensation of the CSNS-II superconducting cavity, which shows the deviation of the beam energy from the design value under the local compensation setting of the energy.

[0029] Figure 9 is the global compensation beam energy deviation from the design value diagram of the embodiment of the application after the failure compensation of the CSNS-II superconducting cavity, which shows the deviation of the beam energy from the design value under the global compensation setting of the energy. DETAILED DESCRIPTION

[0030] The application provides a failure compensation-matching algorithm and system for a high-current superconducting proton linear accelerator, and more specifically, a failure compensation-matching method for a high-current superconducting proton linear accelerator based on a PEE algorithm system, which aims to solve the problems of beam energy reduction and longitudinal phase space structure destruction caused by the failure of superconducting radio frequency cavities. The specific embodiments of the application are described in detail below in conjunction with the accompanying drawings.

[0031] As Figure 1As shown, the PEE algorithm system of this invention mainly includes a fault detection and input module, a PEE algorithm core processing module, a parameter output and execution module, and a verification and feedback module.

[0032] Fault detection and input module: Real-time monitoring or receiving of fault information from the superconducting cavity, determining the location and degree of failure of the superconducting radio frequency cavity where performance degradation or failure has occurred.

[0033] The core processing module of the PEE algorithm is connected to the fault detection and input module, and includes a phase shift compensation unit, an envelope matching unit, and an energy compensation unit that are executed sequentially.

[0034] Phase shift compensation unit: Based on the beam longitudinal transmission model, it adjusts the radio frequency parameters of one or more working cavities in the acceleration cycle of the failed cavity through analytical calculation, restores the longitudinal focusing phase shift, and suppresses the increase in emissivity.

[0035] Envelope matching unit: During at least one acceleration cycle downstream of the failed cavity, optimizes the RF parameters of one or more matching cavities to minimize the matching error between the beam longitudinal envelope and the designed envelope trajectory.

[0036] Energy compensation unit: Under the constraint of keeping the beam focusing intensity of one or more compensation cavities constant, the electric field intensity and synchronization phase of the compensation cavity are adjusted to restore the total beam energy to the design value.

[0037] Parameter output and execution module: Outputs the set of radio frequency parameters calculated by the core processing module to the accelerator low-level control system to update the cavity parameters.

[0038] Verification and Feedback Module: Verifies the recovery effect based on feedback data from the beam diagnostic equipment and triggers necessary re-optimization.

[0039] A failure compensation-matching method for a high-current superconducting proton linear accelerator includes the following steps: S1. Fault Detection Steps: The operating status of the superconducting cavity is monitored in real time through the fault detection and input module. Once performance degradation or failure is detected, the location and degree of failure of the cavity are immediately determined.

[0040] S2. Phase shift compensation steps: as follows Figure 2 As shown, based on the beam longitudinal transmission matrix model, the longitudinal phase shift of one or more working cavities within the acceleration cycle of the failed cavity is restored to the design value by analytically calculating and adjusting the radio frequency parameters (such as synchronization phase) of these cavities. If the failed cavity is partially failed, its own synchronization phase is adjusted; if it is completely failed, the radio frequency parameters of other working cavities within the same cycle are optimized to collaboratively restore the total phase shift of the cycle.

[0041] S3. Envelope matching steps: (e.g., ...) Figure 3As shown, in a limited range (usually 1-2 periods) downstream of the failed cavity, one or more matching cavities are selected, and the radio frequency parameters thereof are optimized using a genetic algorithm to minimize the root mean square error of the longitudinal RMS envelope of the beam from the upstream of the failed cavity to the selected position downstream thereof with respect to the design envelope.

[0042] S4. Energy compensation step The energy compensation strategy includes a local compensation strategy and a global compensation strategy, such as Figure 4 As shown, the local compensation strategy greatly increases the electric field strength of a small number of cavities adjacent to the failed cavity to quickly restore energy; and the global compensation strategy uniformly fine-tunes the electric field strength of multiple cavities in the entire acceleration section containing the failed cavity to make the system parameter change the smoothest. Under the constraint of keeping the bunching strength of the compensation cavity unchanged, a bisection method is used to iteratively solve a unified electric field amplification coefficient or an electric field strength adjustment amount of each cavity that satisfies the energy recovery target.

[0043] Embodiment: applied to China Spallation Neutron Source Phase II (CSNS-II) superconducting linac As shown in the accompanying drawings, the embodiment takes the complete failure of a SPOKE type cavity in the China Spallation Neutron Source Phase II (CSNS-II) superconducting linac as the application scenario. Figures 1-9

[0044] First, system deployment is performed, which is deployed on a high-performance industrial computer and communicates with the accelerator central database, the beam diagnostic system and the low-level radio frequency (LLRF) control system through the EPICS control network. The working execution flow of the PEE algorithm system is as follows: Start: the starting point of the flow, marking the start of the failure compensation process.

[0045] Locate the residual electric field of the fault cavity: through real-time monitoring or receiving of the fault information of the superconducting cavity by the fault detection and input module, the position and failure degree of the superconducting radio frequency cavity with performance degradation or failure are determined, and the residual electric field information of the fault cavity is obtained. This is the basis of the entire compensation process, and provides key data for subsequent judgment and calculation.

[0046] Residual electric field compensation phase shift: this is a judgment node, which judges whether the residual electric field compensation phase shift operation needs to be performed according to the residual electric field of the fault cavity. If the judgment result is “no”, it directly enters the “phase shift compensation calculation” step; if the judgment result is “yes”, it first performs the transverse recovery calculation (although the specific content of the transverse recovery calculation is not expanded in the figure, it is a complete part of the overall system), and then enters the “phase shift compensation calculation” step.

[0047] ​Phase shift compensation calculation: performed by the phase shift compensation unit (121) in the PEE algorithm core processing module. Based on the beam longitudinal transport model, the RF parameters of one or more working cavities in the acceleration period where the failed cavity is located are adjusted through analytical calculation to restore the longitudinal phase shift of the period to the design value. If the failed cavity is partially failed, the phase shift is restored by adjusting its own synchronization phase; if the failed cavity is completely failed, the total phase shift of the period is collaboratively restored by optimizing the RF parameters of other working cavities in the same period.

[0048] Envelope parameter setting: after the phase shift compensation calculation is completed, the envelope matching step is entered. In at least one acceleration period downstream of the failed cavity, the RF parameters of one or more matching cavities are optimized to prepare for subsequent envelope matching calculation.

[0049] Energy compensation calculation: performed by the energy compensation unit in the PEE algorithm core processing module. Under the constraint of keeping the bunching intensity of one or more compensation cavities unchanged, the electric field intensity and synchronization phase of the compensation cavities are adjusted to restore the total beam energy to the design value. The energy compensation step provides at least two strategies: a local compensation strategy, which significantly increases the electric field intensity on a few cavities adjacent to the failed cavity to quickly restore the energy; a global compensation strategy, which uniformly fine-tunes the electric field intensity of multiple cavities in the entire acceleration section containing the failed cavity to make the system parameter change as smooth as possible. In the calculation process, the bisection method is used to iteratively solve the unified electric field amplification coefficient or the field intensity adjustment amount of each cavity that satisfies the energy restoration target.

[0050] Envelope error less than limit: this is a judgment node for judging whether the matching error between the beam longitudinal envelope and the design envelope trajectory after adjustment in the previous steps is less than the set limit value. If the result is "yes", it means that the envelope matching meets the requirements, and the "compensation lattice" step is entered (here, "compensation lattice" can be understood as making corresponding compensation adjustments to the lattice structure and other related parameters of the accelerator to ensure stable operation of the entire system), and then the process ends; if the result is "no", return to the "set envelope parameter" step to re-optimize and adjust the envelope parameters until the envelope error is less than the limit value.

[0051] End: the end point of the process, indicating that after the above series of steps, the failed compensation process of the high-current superconducting proton linear accelerator is completed, and the system returns to normal operating state.

[0052] Throughout the whole process, the fault detection and input module is responsible for providing fault information, which is the starting data source of the process; the PEE algorithm core processing module sequentially performs core operations such as phase shift compensation calculation, envelope matching calculation (including setting envelope parameters and other related operations) and energy compensation calculation; the parameter output and execution module outputs the RF parameter set calculated by the core processing module to the accelerator low-level control system to realize parameter updating and application; the verification and feedback module can verify the recovery effect according to the feedback data of the beam diagnosis equipment, and trigger the necessary re-optimization to form a closed-loop control system, ensuring the accuracy and effectiveness of the failure compensation.

[0053] The specific algorithm execution process in the embodiment is as follows: Fault input: the control system monitors that the electric field gradient of the "SPOKE06-2" cavity drops to zero, determines that it is completely failed, and sends the information to the system of the application.

[0054] Phase shift compensation: the system reads the designed beam optical data, and calculates that the designed zero-flow longitudinal phase shift of the "SPOKE06" period (including SPOKE06-1 and SPOKE06-2 cavities) is 47°.

[0055] Since SPOKE06-2 is completely failed, the algorithm calculates the period phase shift through the transfer matrix analytical formula, and the calculation formula is as follows, which needs to ensure that the period phase shift before and after failure is consistent.

[0056] It is concluded that only the synchronous phase of the SPOKE06-1 cavity in the same period needs to be adjusted from the designed value of-30° to-43°, so that the total phase shift of the period can be restored to 47°. This step is a pure analytical calculation and is completed instantaneously.

[0057] wherein , is the electric field intensity, T is the transit time factor, is the synchronous phase, is the cavity length, is the proton mass, c is the speed of light, are the relative velocity and the relativistic factor of the particle respectively, is the RF electric field wavelength.

[0058] Envelope matching: after phase shift compensation, the Twiss parameters (β, α) of the beam at the SPOKE06 outlet change. The algorithm selects two cavities in the immediately downstream period "SPOKE07" as matching cavities. With the electric field and phase of the two cavities as optimization variables, the genetic algorithm (population size 50, iteration 20 generations) is started, and the optimization goal is to minimize the root mean square error (RMSE) between the designed value of the beam longitudinal RMS envelope from the SPOKE06 inlet to the SPOKE08 outlet.

[0059] The optimization process takes about several minutes, and finds the optimal parameters to make the beam envelope quickly return to the designed trajectory, and the energy oscillation is effectively suppressed.

[0060] Energy compensation (global strategy): After the above adjustment, there is about 2 MeV energy gap of the beam at the outlet of the superconducting section. The algorithm selects uniform compensation on all 20 SPOKE cavities in the superconducting section. Under the constraint of keeping the adjusted phase shift of each cavity unchanged (i.e. E*sinφ is constant), a unified electric field amplification coefficient k is iteratively solved by bisection method.

[0061] After several iterations, k = 1.08 is obtained. That is, the electric field strength of all SPOKE cavities is increased by 8%, and the synchronous phase of each cavity is recalculated accordingly. The field strength of all cavities is increased within the safe redundancy range (<10%).

[0062] Output and execution: The system generates a configuration file containing the new parameters of all 44 superconducting cavities, which is automatically written into the LLRF system by the parameter output and execution module. After the parameter update, the accelerator quickly recovers to stable beam supply.

[0063] As shown in Figures 5-6 , the transverse emittance and longitudinal envelope comparison diagrams of the embodiment before and after the compensation of the CSNS-II superconducting cavity failure are respectively shown. It can be clearly seen from the diagrams that the transverse emittance and longitudinal envelope after the compensation are close to the design values, verifying the effectiveness of the method. The transverse emittance comparison diagram of Figure 5 shows the change of the beam emittance before and after the compensation, and the emittance after the compensation is significantly reduced and close to the design level; Figure 6 the longitudinal envelope comparison diagram shows the change of the beam longitudinal envelope before and after the compensation, and the longitudinal envelope curve after the compensation is highly consistent with the design curve, indicating that the beam quality is significantly improved. As shown in Figure 7 , the embodiment shows the comparison diagram of the global compensation and local compensation electric field settings of the CSNS-II superconducting cavity failure compensation; the electric field strength theoretical value at different transmission distances under the normal design state, the electric field strength setting value at each position under the global compensation strategy, the overall change is gentle, and the electric field strength setting value at each position under the local compensation strategy is significantly improved near the failed cavity. Figures 8-9 The change of the beam energy after the compensation of the embodiment in the CSNS-II superconducting cavity failure is shown, wherein Figure 8 shows the deviation of the beam energy from the design value under the local compensation setting of the energy; Figure 9 shows the deviation of the beam energy from the design value under the global compensation setting of the energy.

[0064] The following table shows the comparison of key beam parameters before and after the compensation by the method of the application after the complete failure of the SPOKE06-2 cavity in the CSNS-II superconducting section simulation environment: As can be known from the example data, the method and system can complete the whole process from fault identification to parameter recovery in several minutes, not only accurately restores the beam energy, but also cooperatively restores the energy spread and emittance representing the beam quality to close to the design level, fully proving the high efficiency, accuracy and engineering practicability.

[0065] The above is only the embodiment of the present application, so that those skilled in the art can implement or use the present application, and is not any limitation on the present application, any simple modification, change and equivalent transformation of the above embodiment according to the technical essence of the present application still belongs to the protection scope of the technical solution of the present application.

Claims

1. A failure compensation-matching method for a high-current superconducting proton linear accelerator, characterized in that, Includes the following steps: Fault detection steps: Determine the location and extent of failure of the superconducting radio frequency cavity where performance degradation or failure has occurred; Phase shift compensation step: Based on the beam longitudinal transmission model, the radio frequency parameters of one or more working cavities in the acceleration cycle where the failed cavity is located are adjusted by analytical calculation so that the longitudinal phase shift of the cycle is restored to the design value; Envelope matching step: During at least one acceleration cycle downstream of the failed cavity, optimize the RF parameters of one or more matching cavities to minimize the matching error between the beam longitudinal envelope and the designed envelope trajectory; Energy compensation step: Under the constraint of keeping the beam focusing intensity of one or more compensation cavities constant, adjust the electric field intensity and synchronization phase of the compensation cavities to restore the total beam energy to the design value.

2. The failure compensation-matching method for a high-current superconducting proton linear accelerator according to claim 1, characterized in that, In the phase shift compensation step, if the failed cavity is partially failed, the phase shift is restored by adjusting its own synchronization phase. If the failed cavity is completely failed, the total phase shift of the cycle can be recovered in a coordinated manner by optimizing the RF parameters of other working cavities in the same cycle.

3. The failure compensation-matching method for a high-current superconducting proton linear accelerator according to claim 1, characterized in that, The envelope matching step is optimized using a genetic algorithm. The objective function of the optimization is the root mean square error between the longitudinal RMS envelope of the beam and the design envelope at a selected position from upstream to downstream of the failure cavity.

4. The failure compensation-matching method for a high-current superconducting proton linear accelerator according to claim 1, characterized in that, The energy compensation step provides at least two strategies: Local compensation strategy: significantly increase the electric field strength in a few cavities adjacent to the failed cavity to quickly restore energy; Global compensation strategy: The electric field intensity of multiple cavities is uniformly fine-tuned throughout the entire acceleration section containing the failed cavity to make the system parameter changes as smooth as possible.

5. The failure compensation-matching method for a high-current superconducting proton linear accelerator according to claim 4, characterized in that, In the energy compensation step, the bisection method is used to iteratively solve for the unified electric field amplification coefficient or the adjustment amount of the field strength of each cavity to satisfy the energy recovery target.

6. A failure compensation-matching system for a high-current superconducting proton linear accelerator, characterized in that, include: The fault detection and input module is used to monitor or receive fault information of the superconducting cavity in real time. The core processing module of the PEE algorithm is connected to the fault detection and input module, and includes a phase shift compensation unit, an envelope matching unit and an energy compensation unit that are executed sequentially. The parameter output and execution module is used to output the set of radio frequency parameters calculated by the core processing module to the accelerator low-level control system.

7. A failure compensation-matching system for a high-current superconducting proton linear accelerator according to claim 6, characterized in that, It also includes a verification and feedback module, which is used to verify the recovery effect based on feedback data from the beam diagnostic equipment and trigger necessary re-optimization.

8. A failure compensation-matching system for a high-current superconducting proton linear accelerator according to claim 6, characterized in that, The fault detection and input module communicates with the database through the accelerometer control network, and the parameter output and execution module generates a parameter configuration file that can directly drive the low-level control system to update the cavity parameters.

9. A failure compensation-matching method for a high-current superconducting proton linear accelerator according to any one of claims 1 to 5, characterized in that, The phase shift compensation, envelope matching, and energy compensation steps decouple the complex recovery problem and combine analytical methods with local optimization to reduce the computation time from hours in traditional methods to less than ten minutes, achieving high-precision coordinated recovery of beam energy, energy dissipation, and emittance.

10. A high-current superconducting proton linear accelerator failure compensation-matching system according to any one of claims 6 to 8, automatically executing the method flow of any one of claims 1 to 5, characterized in that, The system significantly improves the reliability and availability of accelerator operation, reducing the recovery time to less than ten minutes.

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