A high-frequency system for proton and helium ion therapy devices and its method of use

Abstract

This invention provides a high-frequency system for proton and helium ion therapy devices, comprising: a low-level control system including an amplitude control module, a frequency control module, and a phase control module, which control a vector modulation signal; a power source system that receives the vector modulation signal and provides a power signal; and a high-frequency cavity system including a high-frequency cavity, which is a vacuum chamber pipe fitted with multiple magnetic alloy rings; wherein, by controlling the vector modulation signal, the resonant frequency of the high-frequency cavity is adjusted according to the cyclotron frequency of the particles, so that protons and helium ions can be stably accelerated each time they pass through the high-frequency cavity. This invention also provides a corresponding method of use. The system of this invention simultaneously accelerates protons and helium ions within the same synchrotron accelerator.

Description

Technical Field

[0001] This invention belongs to the field of synchrotron technology, and particularly relates to a high-frequency system for proton and helium ion therapy devices and its usage method. Background Technology

[0002] Proton therapy is currently the most advanced and widely used mainstream technology for tumor radiotherapy internationally. Clinical results show that proton therapy has advantages such as high precision, high cure rate, and few side effects. Helium ion therapy can compensate for the shortcomings of proton therapy for different types of tumors. Integrating proton and helium ion technologies into the same treatment device allows for wider application and meets the needs of both proton and helium ion tumor treatment.

[0003] A synchrotron typically includes a high-frequency system for acceleration, magnetic elements, and vacuum conduits connecting the magnetic elements and the high-frequency cavity. In a synchrotron, the high-frequency system primarily accelerates particles by generating high voltage, while the magnetic elements confine the particles to a specific orbital range, preventing them from striking the vacuum conduit walls and being lost. All components are connected via vacuum flanges.

[0004] High-frequency systems are a key technology in proton and helium ion therapy devices. Therapeutic devices that simultaneously accelerate both protons and helium ions have not been proposed before, therefore, there are no high-frequency systems specifically designed for these two particles. Existing high-frequency systems cannot simultaneously meet the requirements for proton and helium ion simultaneous acceleration. This is because if the same high-frequency system is to be used in both proton and helium ion therapy devices, it must simultaneously meet the requirements for proton and helium ion simultaneous acceleration. Furthermore, a high-frequency system shared by both protons and helium ions needs to provide a wider operating bandwidth than existing high-frequency systems to meet the requirements of simultaneous acceleration without frequency tuning. Summary of the Invention

[0005] The present invention aims to provide a high-frequency system and method of use for proton and helium ion therapy devices, so as to simultaneously accelerate protons and helium ions within the same synchrotron.

[0006] To achieve the above objectives, the present invention provides a high-frequency system for a proton and helium ion therapy device, comprising: a low-level control system including an amplitude control module, a frequency control module, and a phase control module, which control a vector modulation signal; a power source system that receives the vector modulation signal and provides a power signal; and a high-frequency cavity system including a high-frequency cavity, which is a vacuum chamber pipe fitted with multiple magnetic alloy rings; wherein, by controlling the vector modulation signal, the resonant frequency of the high-frequency cavity is adjusted according to the cyclotron frequency of the particles, so that protons and helium ions can obtain stable acceleration each time they pass through the high-frequency cavity.

[0007] The low-level control system also includes a signal source and a central control system connected to the signal source to receive a reference frequency signal. The amplitude control module, frequency control module, and phase control module are all connected to the central control system and the power source system.

[0008] The central control system is connected to both the directional coupler and the high-frequency cavity to acquire power reflection signals and cavity pressure signals. The central control system performs vector modulation analysis based on the acquired power reflection signals and cavity pressure signals to output control commands for the amplitude control module, frequency control module, and phase control module. The vector modulation signals are then controlled through these three modules.

[0009] The high-frequency cavity accelerates protons and helium ions independently and not simultaneously.

[0010] The power source system is a solid-state power source, and the power signal output by the power source system includes continuous power signal and pulse power signal.

[0011] The high-frequency cavity system also includes a power transmission coaxial feed tube connected to the power source system. The high-frequency cavity includes a cavity shell, flanges located at both ends of the cavity shell and connected to the beam vacuum pipe, an acceleration gap located on the vacuum chamber pipe to generate an acceleration voltage, a capacitor electrically connected to both ends of the acceleration gap, and a transmitter connected between the capacitor and the power transmission coaxial feed tube. The vacuum chamber pipe is located between the flanges to allow the beams of protons and helium ions to pass through. The magnetic alloy ring is located inside the cavity shell.

[0012] The high-frequency cavity has a total length of 800mm, a lateral dimension of 600mm, and a beam aperture of 130mm.

[0013] On the other hand, the present invention provides a method of using a high-frequency system for proton and helium ion therapy devices, comprising:

[0014] Step S1: Provide a high-frequency system for proton and helium ion therapy devices as described above;

[0015] Step S2: For each type of particle, when the particle first arrives at the high-frequency cavity, the cyclotron frequency of the particle is determined based on the particle's rest energy and kinetic energy, and the resonant frequency of the high-frequency cavity is adjusted to an integer multiple of the particle's cyclotron frequency so that the particle gains energy and the cyclotron frequency of the particle is determined again.

[0016] Step S3: Determine the moment when the particle arrives at the high-frequency cavity again after one revolution based on the particle's cyclotron frequency. At this moment, adjust the resonant frequency of the high-frequency cavity to an integer multiple of the particle's cyclotron frequency, so that the particle gains energy and the particle's cyclotron frequency is determined again.

[0017] Step S4: Repeat steps S2-S3 until the particle reaches its highest energy.

[0018] Between steps S1 and S2, the process further includes: receiving a particle injection command, completing preparations according to the particle type, and then proceeding to step S1; and step S4 further includes: after completing the particle energy boost, stopping the adjustment of the high-frequency cavity resonant frequency and waiting for the next command.

[0019] The high-frequency system for proton and helium ion therapy of the present invention utilizes a single high-frequency system within the same synchrotron, employing frequency modulation technology based on a high-frequency cavity and low-level control. This allows protons and helium ions to achieve stable acceleration and increased particle energy after passing through the high-frequency cavity. This technical solution enables a single high-frequency system to separately accelerate and increase the energy of protons and helium ions within the same synchrotron. Furthermore, the high-frequency cavity of the high-frequency system for proton and helium ion therapy of the present invention uses a magnetic alloy ring, which is suitable for simultaneous acceleration of protons and helium ions without the need for a tuner to adjust the frequency. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of a high-frequency system for a proton and helium ion therapy device according to the first embodiment of the present invention.

[0021] Figure 2 This is a schematic diagram of a low-level control system for a proton and helium ion therapy device according to the present invention.

[0022] Figure 3 This is a schematic diagram of the high-frequency cavity structure for a proton and helium ion therapy device according to the present invention. Detailed Implementation

[0023] The embodiments of the present invention are given below with reference to the accompanying drawings and described in detail.

[0024] like Figure 1The diagram shows a schematic representation of a high-frequency system for a proton and helium ion therapy device according to a first embodiment of the present invention. The high-frequency system is located within a synchrotron ring accelerator, and can be configured as a single unit or multiple units depending on the acceleration energy and period of the protons and helium ions.

[0025] To simultaneously meet the requirements for proton and helium ion synchronous acceleration, the design parameters of the high-frequency system are as follows: resonant frequency: 4.45MHz; quality factor: 0.5; peak voltage: 2kV. The long bandwidth here refers to the operating bandwidth of 0.5MHz to 10MHz. Synchronous acceleration without frequency tuning means that within this operating bandwidth of 0.5MHz to 10MHz, the high-frequency system meets the conditions for synchronous acceleration of protons and helium ions without requiring tuning of the high-frequency cavity's operating frequency.

[0026] like Figure 1 As shown, the high-frequency system for the proton and helium ion therapy device includes a low-level control system 11, a power source system 21, and a high-frequency cavity system 31 connected in sequence.

[0027] One low-level control system 11 is provided and connected to the aforementioned power source system 21. It is configured to control the vector modulation signal output by the control system to adjust the resonant frequency (i.e., operating frequency) of the high-frequency cavity 302 according to the cyclotron frequency of the particles, ensuring that protons and helium ions receive stable acceleration each time they pass through the high-frequency cavity 302. The acceleration of protons and helium ions by the high-frequency cavity 302 is independent and not simultaneous.

[0028] The low-level control system 11 does not require structural modifications. During operation, protons and helium ions are not used simultaneously; that is, in the synchrotron, only either protons or helium ions are used at any given time. The low-level control system 11 is equally applicable to both protons and helium ions. It should be noted that although the same high-frequency system can be used simultaneously for proton and helium ion therapy devices, the particle synchronization acceleration function implemented by the high-frequency system for the proton and helium ion therapy devices is not performed simultaneously. The high-frequency system is used to meet the synchronization acceleration function of each proton and helium ion therapy device during their respective applications.

[0029] like Figure 2As shown, in this embodiment, the low-level control system 11 includes a signal source 12, a central control system 13 connected to the signal source 12 to receive a reference frequency signal, and an amplitude control module 14, a frequency control module 15, and a phase control module 16 connected to the central control system 13. The vector modulation signal output by the low-level control system 11 is the modulation and mixing result of the output signals of the amplitude control module 14, the frequency control module 15, and the phase control module 16. Specifically, a vector modulation signal generated by the low-level control system 11 through its amplitude control module 14, frequency control module 15, and phase control module 16 via modulation and mixing up-conversion is connected to the power source system 21 via a cable; therefore, the vector modulation signal serves as the input signal to the power source system 21.

[0030] The reference frequency signal provided by signal source 12 is a fixed-frequency signal. The frequency of this reference frequency signal depends on the energy of the protons and helium ions. The particle velocity and cyclotron frequency can be calculated based on the energy. This reference frequency signal is a positive integer multiple of the cyclotron frequency. In this embodiment, the reference frequency signal is in the microwave band.

[0031] The central control system 13 is the upper-level software in the low-level control system 11. The central control system 13 is connected to both the directional coupler and the high-frequency cavity 302 to acquire power reflection signals (including the forward and reverse signals of the directional coupler) and cavity pressure signals. The central control system 13 performs vector modulation analysis based on the acquired power reflection signals and cavity pressure signals to output control commands to the amplitude control module 14, frequency control module 15, and phase control module 16. The vector modulation signals are controlled through these three modules to achieve closed-loop control.

[0032] The amplitude control module 14, frequency control module 15, and phase control module 16 are each comprised of one set. The amplitude control module 14 outputs an amplitude signal, and the phase control module 16 outputs a phase signal. After modulation, the amplitude control module 14 and the phase control module 16 output an initial vector modulation signal. The reference signal is down-converted to obtain an intermediate frequency (IF) signal. Specifically, the reference signal provided by the signal source 12 undergoes frequency division, frequency multiplication, and mixing to obtain the IF signal. The frequency control module 15 changes the actual output frequency of the IF signal corresponding to the reference frequency signal by mixing the reference signal. Then, it up-converts the initial vector modulation signal with the IF signal to change the frequency of the vector output signal, outputting the final vector modulation signal that reaches the actual output frequency. This signal is used to drive the power source system 21 to feed microwave power into the high-frequency cavity system 31, thereby establishing the electromagnetic field in the high-frequency cavity system 31.

[0033] Specifically, the central control system 13 acquires the power reflection signal and cavity pressure signal using an ADC, followed by delay, IQ demodulation, reference signal tracking, vector calibration, CORDIC (Coordinate Rotation Digital Algorithm) modulation calculation, error deviation modulation, PI (Proportional-Integral) control, vector flipping, and modulation with feedforward settings. After compensation, the final vector modulated signal is output by the DAC (Digital-to-Analog Converter). The DAC is a combination of the amplitude control module 14, the frequency control module 15, and the phase control module 16.

[0034] The central control system 13 is configured to send control commands to the frequency control module 15 to increase or decrease the frequency when the reflected power of the power reflected signal is too high, in order to find the point (resonant frequency) with the lowest reflected power of the power reflected signal as the actual output frequency of the vector modulation signal. The central control system 13 is also configured to compare the cavity pressure signal of the high-frequency cavity with the vector modulation signal to determine if a frequency shift has occurred, and to compensate for the frequency using an adaptive algorithm. Furthermore, the optimal beam operating state is found, and the amplitude and phase at the optimal beam operating state are set as target amplitude and phase values. When the amplitude or phase of the cavity pressure signal is detected to exceed these target values, the central control system 13 sends a control command to the amplitude control module to decrease the amplitude output / to the phase control module to decrease the phase output. When the amplitude or phase is lower than these target values, the central control system 13 sends a control command to the amplitude control module to increase the amplitude output / to the phase control module to increase the phase output.

[0035] For high-frequency systems, the optimal operating state of the beam is to provide a stable and synchronous high voltage to the particle beam to enhance its energy. Under optimal conditions, the power reflection is minimized, meaning all power is fed into the high-frequency cavity, the acquired cavity pressure signal is 2kV, and the amplitude variation is within 0.1%.

[0036] The power source system 21 is a single set, configured to receive vector modulation signals from the low-level control system 11 and provide a power signal.

[0037] like Figure 2 The amplitude control module 14, frequency control module 15, and phase control module 16 of the low-level control system 11 are connected to the power source system 21; the signal source 12 of the low-level control system 11 is configured to provide a reference frequency signal, and the power source system 21 is configured to output a power signal, the power signal including a continuous power signal and a pulse power signal.

[0038] A continuous power signal means the output power is continuous, while a pulse means the output power is not continuous; it is a pulsed output. The duty cycle, pulse width, and repetition frequency of a pulse are adjustable.

[0039] The power source system 21 is a solid-state power source, connected to the high-frequency cavity system 31 via a power transmission coaxial feed tube, and connected to the low-level control system 11 via three modules: amplitude control module 14, frequency control module 15, and phase control module 16. The power source system 21 needs to meet the requirement of a 2kV accelerating voltage for both protons and helium ions. Therefore, compared to existing technologies, the power source system needs to increase its output power. The total output power of the power source system 21 is synthesized from multiple individual power modules. Therefore, power modules are added, and a power combiner is used to synthesize the output signal of the power source, providing higher power output. In this embodiment, the input signal of each power module is the input signal of the power source system 21. The input signal of the power source system 21 is amplified by a preamplifier and then distributed to each power module by a power divider. Each power module discharges the input signal, with an output power of 200W. The entire power source system consists of 16 power modules, achieving a combined output of 3000W.

[0040] The number of high-frequency cavity systems 31 may be one set, which is connected to the power source system 21. It includes a power transmission coaxial feed tube 301 connected to the power source system 21 and a high-frequency cavity 302 connected to the power transmission coaxial feed tube 301. The power signal enters the high-frequency cavity 302 to excite an electromagnetic field inside the high-frequency cavity 302.

[0041] The high-frequency cavity 302 is equipped with the function of simultaneously accelerating protons and helium ions. It is configured to generate an accelerating voltage within the high-frequency cavity 302 through the feed power from the power source system 21, so that protons and helium ions are accelerated after passing through the gap containing the accelerating voltage. The high-frequency cavity system 31 is connected to the power source system 21 and provides power through a power transmission coaxial feed tube 301 and a directional coupler. The power source system 21, the directional coupler, and the high-frequency cavity 302 can all be regarded as devices with coaxial interfaces. The three are connected through the power transmission coaxial feed tube. That is, the power transmission coaxial feed tube connects the power source system 21 to the directional coupler, and also connects the directional coupler to the high-frequency cavity 302.

[0042] like Figure 3The diagram shows the structure of the high-frequency cavity 302, which is a vacuum chamber tube fitted with multiple magnetic alloy ring plates 33. The specific dimensions of the high-frequency cavity 302 are: total length: 800mm, lateral dimension: 600mm, beam aperture: 130mm. In this invention, the high-frequency cavity is a cavity with a very low quality factor and a wide operating bandwidth. Specifically, within the lowest and highest cyclotron frequencies of protons and helium ions, the high-frequency cavity can operate normally without frequency adjustment. During operation, the resonant frequency of the high-frequency cavity is changed by the low-level control system 11 according to the cyclotron frequency of the protons or helium ions, so that the particles are accelerated each time they pass through the high-frequency cavity.

[0043] like Figure 3 As shown, the high-frequency cavity 302 includes a cavity shell 37, flanges 32 disposed at both ends of the cavity shell 37 and connected to the beam vacuum pipe, a vacuum chamber pipe 34 disposed between the flanges 32 for the passage of the proton and helium ion beam, a magnetic alloy ring 33 disposed inside the cavity shell 37 and sleeved on the outside of the vacuum chamber pipe 34, an acceleration gap 35 disposed on the vacuum chamber pipe 34 to generate an acceleration voltage, a capacitor 36 electrically connected to both ends of the acceleration gap 35, and a transmitter 38 connected between the capacitor 36 and the power transmission coaxial feed tube 301. Thus, the power source system 21 charges the acceleration gap through the power transmission coaxial feed tube 301 and the capacitor 36.

[0044] The acceleration gap 35 is equivalent to two electrode plates, one positive and one negative. A voltage exists between the two electrode plates, and charged particles gain energy when passing through the acceleration gap 35. The outer shell 37 of the cavity is made of stainless steel.

[0045] like Figure 3 As shown, the flange 32 is connected to the upstream and downstream structures in the synchrotron, the center of the flange 32 is consistent with the beam center of the synchrotron, and the center of the vacuum chamber pipe 34 is consistent with the beam center of the synchrotron.

[0046] The magnetic alloy ring 33 is a material used to reduce the quality factor of the high-frequency cavity, ensuring that the high-frequency cavity 302 has sufficient bandwidth so that the high-frequency cavity 302 can still work when the proton and helium ion cyclotron cycles change.

[0047] The acceleration gap 35 is the position where protons and helium ions obtain an acceleration voltage through the vacuum chamber pipe 34, and the acceleration voltage is set to the voltage value obtained by protons and helium ions in a single cycle.

[0048] Therefore, the high-frequency cavity system 31 has been improved in this invention to make it suitable for both proton and helium ion treatment devices, fulfilling the function of synchronously accelerating protons and helium ions respectively. Both protons and helium ions have a minimum cyclotron frequency at their lowest energy and a maximum cyclotron frequency at their highest energy. For a single particle, the operating frequency of the high-frequency cavity system 31 must cover both the minimum and maximum cyclotron frequencies. For a high-frequency system using both protons and helium ions, the high-frequency cavity system 31 needs to simultaneously satisfy both the minimum and maximum cyclotron frequencies of protons and helium ions to make it suitable for both proton and helium ion treatment devices. In this embodiment, to achieve synchronous acceleration of protons and helium ions, the operating bandwidth of the high-frequency cavity system needs to be between 0.5MHz and 10MHz, requiring improvements to the internal magnetic alloy and capacitance distribution of the high-frequency cavity.

[0049] Therefore, through the above-mentioned improvements to the high-frequency cavity and power source system, the high-frequency cavity and power source system both meet the operating frequency range and power requirements required for the operation of protons and helium ions, so that protons and helium ions can run according to predetermined orbits and energies during their respective operations.

[0050] On the other hand, the present invention provides a method of using a high-frequency system for a proton and helium ion therapy device, which utilizes its low-level control system 11 to change the frequency of the high-frequency cavity according to the energy of different particles during operation, so that protons and helium ions can obtain stable acceleration when they run independently; the low-level control system 11, according to the different cyclotron cycles of protons and helium ions, presets rules to make protons and helium ions accelerate when passing through the high-frequency cavity.

[0051] This invention provides a method of using a high-frequency system for proton and helium ion therapy devices, comprising:

[0052] Step S1: Provide the high-frequency system for proton and helium ion therapy devices as described above;

[0053] Step S2: For each type of particle, when the particle first arrives at the high-frequency cavity, the cyclotron frequency of the particle is determined based on the particle's rest energy and kinetic energy, and the resonant frequency of the high-frequency cavity is adjusted to an integer multiple of the particle's cyclotron frequency so that the particle gains energy boost, and the cyclotron frequency of the particle is determined again; the particles include protons and helium ions.

[0054] When particles (such as protons and helium ions) travel through a synchrotron, their relativistic velocity can be calculated based on their current energy. Simultaneously, the period when the particle returns to the high-frequency cavity after one revolution, based on the synchrotron's circumference, can be calculated, and thus the operating frequency of the high-frequency cavity can be determined. Because helium ions have different weights and therefore different velocities at the same energy, their orbital periods and frequencies differ. Therefore, even with the same energy, the high-frequency cavity will have different frequencies for the two types of particles.

[0055] For different particles, assume the particle's kinetic energy E k Given rest energy E0 and synchrotron circumference L, the particle cyclotron frequency is: f = c * sqrt(1 - (E0 / (E0 + E0)) / (E0 + E0 ... k ))^2) / L, where f is the ionic cyclotron frequency, E k Let E0 be the kinetic energy of the particle, L be the circumference of the synchrotron, c be the speed of light, and sqrt() be the square root function. When different particles have the same kinetic energy, their cyclotron frequencies f are different due to their different rest energies. The resonant frequency of the high-frequency cavity is f0 = n × f, where n is a positive integer.

[0056] Step S3: Determine the moment when the particle arrives at the high-frequency cavity again after one revolution based on the particle's cyclotron frequency. At this moment, adjust the resonant frequency of the high-frequency cavity to an integer multiple of the particle's cyclotron frequency, so that the particle gains energy and the particle's cyclotron frequency is determined again.

[0057] After one acceleration, the particle's kinetic energy increases, the corresponding relativistic velocity increases, and the cyclotron frequency increases. At this time, the resonant frequency of the high-frequency cavity must also increase accordingly to ensure that the particle achieves maximum acceleration when it returns to the high-frequency cavity.

[0058] Step S4: Repeat steps S2-S3 until the particle reaches its highest energy.

[0059] The highest energy of a proton is 235 MeV / u, and the highest energy of a helium ion is 235 MeV / u. MeV / u represents the energy of each nucleon. The mass of a proton is 1, and the mass of a helium ion is 4 times that of a proton. It can also be said that the highest energy of a proton is 235 MeV, and the highest energy of a helium ion is 940 MeV.

[0060] Between steps S1 and S2, the process further includes: receiving a particle injection command, completing preparations according to the particle type, and then proceeding to step S1; and step S4 further includes: after completing the particle energy boost, stopping the adjustment of the high-frequency cavity resonant frequency and waiting for the next command.

[0061] The preparatory work here refers to the particles running in the synchrotron, but the high-frequency system acceleration function has not yet been activated. The particles will not be accelerated or have their energy increased, and the high-frequency system is in standby mode. Once the high-frequency system is activated, the particles will be accelerated and their cyclotron frequency will change.

[0062] The preparation work here refers to the particles running in the synchrotron, but before the high-frequency system acceleration function is activated, the particles will not be accelerated or have their energy increased, and the high-frequency system is in standby mode. Once the high-frequency system is activated, the particles will be accelerated and their cyclotron frequency will change.

[0063] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the invention. Various variations can be made to the above embodiments of the present invention. That is, all simple and equivalent changes and modifications made based on the claims and description of this invention fall within the protection scope of the claims of this patent. All aspects not described in detail in this invention are conventional technical content.

Claims

1. A method of using a high-frequency system for proton and helium ion therapy devices, characterized in that, include: Step S1: Provide a high-frequency system for proton and helium ion therapy devices; The high-frequency system for the proton and helium ion therapy device includes: The low-level control system includes an amplitude control module, a frequency control module, and a phase control module, which control the vector modulation signal. A power source system that receives a vector modulation signal and provides a power signal; and A high-frequency cavity system includes a high-frequency cavity, which is a vacuum chamber pipe fitted with multiple magnetic alloy ring plates; In this process, the resonant frequency of the high-frequency cavity is adjusted according to the cyclotron frequency of the particles by controlling the vector modulation signal, so that protons and helium ions can be stably accelerated each time they pass through the high-frequency cavity. The low-level control system further includes a signal source and a central control system connected to the signal source to receive a reference frequency signal. The amplitude control module, frequency control module, and phase control module are all connected to the central control system, and the vector modulation signal generated by the amplitude control module, frequency control module, and phase control module through modulation and mixing up-conversion is connected to the power source system. The central control system is simultaneously connected to the directional coupler and the high-frequency cavity to acquire power reflection signals and cavity pressure signals. Based on the acquired power reflection and cavity pressure signals, the central control system performs vector modulation analysis to output control commands to the amplitude control module, frequency control module, and phase control module. These three modules then control the vector modulation signal. The central control system compares the cavity pressure signal of the high-frequency cavity with the vector modulation signal to determine if a frequency shift has occurred and compensates for the frequency using an adaptive algorithm. It then finds the optimal beam operating state and sets the amplitude and phase of the beam at the optimal operating state. The settings are set to target amplitude and phase values. When the amplitude or phase of the detected cavity pressure signal exceeds these target values, the central control system sends a control command to the amplitude control module to reduce the amplitude output / to the phase control module to reduce the phase output. When the amplitude or phase is lower than these target values, the central control system sends a control command to the amplitude control module to increase the amplitude output / to the phase control module to increase the phase output. Under optimal beam operating conditions, the collected power reflection is the lowest, the collected cavity pressure signal is 2kV, and the amplitude variation range is within 0.1%. The high-frequency cavity accelerates protons and helium ions independently and not simultaneously. Step S2: For each type of particle, when the particle first arrives at the high-frequency cavity, the cyclotron frequency of the particle is determined based on the particle's rest energy and kinetic energy, and the resonant frequency of the high-frequency cavity is adjusted to an integer multiple of the particle's cyclotron frequency so that the particle gains energy and the cyclotron frequency of the particle is determined again. Step S3: Determine the moment when the particle arrives at the high-frequency cavity again after one revolution based on the particle's cyclotron frequency. At this moment, adjust the resonant frequency of the high-frequency cavity to an integer multiple of the particle's cyclotron frequency, so that the particle gains energy and the particle's cyclotron frequency is determined again. Step S4: Repeat steps S2-S3 until the particle reaches its highest energy.

2. The method of using the high-frequency system for proton and helium ion therapy devices according to claim 1, characterized in that, The power source system is a solid-state power source, and the power signal output by the power source system includes continuous power signal and pulse power signal.

3. The method of using the high-frequency system for proton and helium ion therapy devices according to claim 1, characterized in that, The high-frequency cavity system also includes a power transmission coaxial feed tube connected to the power source system. The high-frequency cavity includes a cavity shell, flanges located at both ends of the cavity shell and connected to the beam vacuum pipe, an acceleration gap located on the vacuum chamber pipe to generate an acceleration voltage, a capacitor electrically connected to both ends of the acceleration gap, and a transmitter connected between the capacitor and the power transmission coaxial feed tube. The vacuum chamber pipe is located between the flanges to allow the beams of protons and helium ions to pass through. The magnetic alloy ring is located inside the cavity shell.

4. The method of using the high-frequency system for proton and helium ion therapy devices according to claim 3, characterized in that, The high-frequency cavity has a total length of 800mm, a lateral dimension of 600mm, and a beam aperture of 130mm.

5. The method of using the high-frequency system for proton and helium ion therapy devices according to claim 1, characterized in that, Between steps S1 and S2, the process further includes: receiving a particle injection command, completing preparations according to the particle type, and then proceeding to step S1; and step S4 further includes: after completing the particle energy boost, stopping the adjustment of the high-frequency cavity resonant frequency and waiting for the next command.

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