A medical cyclotron and ignition protection method

Abstract

The present application relates to the field of accelerator technology, and specifically to a medical cyclotron and spark protection method, the method comprising: obtaining a reflected power signal and an incident power signal of the medical cyclotron at a preset sampling frequency; a preset window, and obtaining a signal disorder value based on the signal difference of the reflected power; determining whether the moment when the signal disorder value is the largest is the moment when the spark event occurs; obtaining the reflected power of the interference source based on the distribution of the reflected power signal in the window corresponding to the moment when the spark event occurs; obtaining the result lag time; combining the reflected power signals at each moment to obtain the spark signal strength value at the current moment; and combining the incident power signal and the signal sampling frequency to determine whether the medical cyclotron needs to enter a spark response state. The present application aims to incorporate the power size of the reflected power signal into the spark event intensity judgment, more accurately evaluate the spark intensity, improve the response sensitivity, and protect the medical cyclotron.

Description

Technical Field

[0001] The present application relates to the field of accelerator technology, and in particular to a medical cyclotron and an ignition protection method. Background Art

[0002] In medical cyclotrons, detecting and addressing sparking is crucial to ensuring safe operation. Sparking typically refers to abnormal discharges caused by an impure cavity surface, insufficient vacuum, or other factors under the influence of a high-frequency electric field. This discharge can cause transient reflections of RF power, potentially damaging the accelerator's electronic equipment. During operation, a medical cyclotron detects sparking based on a sharp drop in the cavity signal. When sparking occurs, the control system rapidly responds by shutting down the RF switch, thereby terminating RF excitation and protecting the hardware.

[0003] However, not all sparks require immediate accelerator shutdown. Some momentary sparks may not cause damage to the accelerator, so if the spark lasts only a short time, it may not be considered a spark requiring immediate action. This requires the spark protection system to accurately detect the start and end of sparks to avoid unnecessary downtime and maintenance.

[0004] Current methods typically rely on setting empirical thresholds for input and reflected power to detect spark events. They then use a fixed detection time to assess the severity of the spark, taking action only when the spark is severe. This approach, which judges spark severity solely based on detection time, fails to fully account for power differences among spark events. This can lead to inaccurate spark assessments, insensitive spark protection responses, and potentially damage to medical cyclotrons. Summary of the Invention

[0005] In view of the above, it is necessary to provide a medical cyclotron and an ignition protection method to solve the above problems.

[0006] A first aspect of the present application provides a method for protecting a medical cyclotron from sparking, the method comprising:

[0007] Acquire the reflected power signal and incident power signal of the medical cyclotron at a preset sampling frequency;

[0008] The reflected power at each moment is used as the preset window of the central element, and the signal disorder value at each moment is obtained based on the spectrum difference of the reflected power signal on both sides of the central element;

[0009] Based on the distribution difference of the reflected power signals on both sides of the central element in each window corresponding to the moment when the signal disorder value in each window is the largest, it is determined whether the corresponding moment is the moment when the ignition event occurs;

[0010] According to the distribution of the reflected power signal in the window corresponding to the time when the ignition event occurs, the reflected power of the interference source at the time when the ignition event occurs is obtained;

[0011] The result lag time is obtained based on the number of signals in the window and the sampling frequency of the signal; the ignition signal strength value is obtained based on the interference source reflection power at the time corresponding to the result lag time before the ignition event occurs, combined with the reflection power signal at each time;

[0012] According to the ignition signal strength value, combined with the incident power signal at the current moment and the signal sampling frequency, it is determined whether the medical cyclotron needs to enter the ignition response state.

[0013] The signal disorder value at each moment is obtained as follows:

[0014] In the window corresponding to the reflected power signal at each moment, the sub-window consisting of the elements at all moments before the moment when the central element in the window is obtained is recorded as the left window; the sub-window consisting of the elements at all moments after the moment when the central element in the window is obtained is recorded as the right window;

[0015] The spectrum corresponding to the reflected power signal in the left window and the right window is recorded as the left window spectrum and the right window spectrum respectively;

[0016] The distance between the left window spectrum and the right window spectrum of the reflected power signal at each moment is measured and recorded as the signal disorder value at each moment.

[0017] The determination of whether the corresponding moment is the moment when the ignition event occurs is specifically as follows:

[0018] In the window corresponding to the filtered moment, obtain the left window spectrum mean and the right window spectrum mean; if the left window spectrum mean is less than the right window spectrum mean, it is determined that the corresponding moment is the moment when the ignition event occurs.

[0019] The process of obtaining the interference source reflected power at the time when the ignition event occurs includes:

[0020] In the window corresponding to the time when the ignition event occurs, the average level of the reflected power signal in the left window is used as the interference source reflected power at the time when the ignition event occurs.

[0021] The result lag time is specifically the ratio of the number of time intervals in the window to the signal sampling frequency; wherein the number of time intervals in the window is determined by the difference between the number of sampling points in the window and 1.

[0022] The process of determining whether to obtain the ignition signal strength value includes:

[0023] If the spectrum mean of the left window is less than or equal to the spectrum mean of the right window in all windows between the time when the ignition event occurs and the current time, calculate the ignition signal strength value at the current time;

[0024] Otherwise, the ignition signal strength value at the current moment is not calculated, and the ignition signal strength value is calculated until the next ignition event occurs.

[0025] The calculation of the current ignition signal strength value includes:

[0026] The ignition power signal at each moment is obtained based on the difference between the reflected power signal at each moment after the ignition event occurs and the interference source reflected power at the moment corresponding to the result lag time before the ignition event occurs;

[0027] The accumulated sum of the ignition power signals from the time the ignition event occurs to the current time is taken as the ignition signal strength value at the current time.

[0028] The determination of whether the medical cyclotron needs to enter the ignition response state is specifically as follows:

[0029] An intensity threshold is obtained based on the incident power signal at the current moment in combination with the signal sampling frequency; if the intensity of the ignition event is greater than the intensity threshold, it is determined that the medical cyclotron needs to enter the ignition response state.

[0030] The formula for the intensity threshold is: , where LM is the intensity threshold, F is the sampling frequency of the signal, d is the preset ignition judgment coefficient, Pi is the incident power at the current moment, and T is the ignition duration.

[0031] In a second aspect, an embodiment of the present application further provides a medical cyclotron, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor implements the steps of any one of the above methods when executing the computer program.

[0032] In the above scheme, the reflected power signal and the incident power signal of the medical cyclotron are obtained at a preset sampling frequency, which provides a data basis for the subsequent detection and analysis of the ignition event and the understanding of the working state of the medical cyclotron when the ignition occurs; the reflected power at each moment is used as the central element to preset the window, and the signal disorder value at each moment is obtained according to the spectrum difference of the reflected power signal on both sides of the central element, which helps to accurately screen out the start and end time of the ignition event of the medical cyclotron in the subsequent time; according to the distribution difference of the reflected power signal on both sides of the central element in the window corresponding to the moment with the largest signal disorder value in each window, it is judged whether the corresponding moment is the moment of the ignition event, and the accurate moment of the ignition event is obtained, thereby improving the accuracy of the subsequent control of the ignition event; according to the reflection power in the window corresponding to the moment of the ignition event, the signal disorder value at each moment is obtained. The distribution of power signals is used to obtain the interference source reflected power at the time of the ignition event, which helps to eliminate the influence of the medical cyclotron on the judgment of the intensity of the ignition event by using the reflected power signal when the ignition event does not occur. According to the number of signals in the window and the sampling frequency of the signal, the result lag time is obtained to characterize the delay of the calculation result relative to the actual time when the signal occurs. Based on the interference source reflected power at the time corresponding to the result lag time before the ignition event, combined with the reflected power signal at each time, the ignition signal strength value at the current time is obtained. The method of incorporating the power of the reflected power signal generated by the ignition event into the ignition event intensity judgment can more comprehensively consider the intensity differences of the ignition event at different times compared to the existing evaluation method that only relies on the duration of the ignition event. This method makes the evaluation of the intensity of the ignition event more accurate and improves the response sensitivity to the ignition event, thereby effectively protecting the medical cyclotron from potential damage. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A flowchart of a method for protecting a medical cyclotron from sparking, provided in accordance with one embodiment of the present application;

[0034] Figure 2 A flowchart for obtaining the ignition signal strength value provided in one embodiment of the present application. DETAILED DESCRIPTION

[0035] In the description of the embodiments of this application, words such as "exemplary," "or," and "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of this application should not be construed as being preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary," "or," and "for example" is intended to present the relevant concepts in a concrete manner.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the art of this application. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0037] It should also be noted that the terms "first" and "second" in this application and the accompanying drawings are used to distinguish similar objects, rather than to describe a specific order or sequence. The methods disclosed in the embodiments of this application or the methods shown in the flowcharts include one or more steps for implementing the methods. Without departing from the scope of protection of this application, the order of executing multiple steps can be interchanged with each other, and some steps can also be deleted.

[0038] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0039] The following describes in detail a medical cyclotron and a specific solution of an ignition protection method provided by the present application with reference to the accompanying drawings.

[0040] See also Figure 1 , which shows a flowchart of a medical cyclotron ignition protection method provided by one embodiment of the present application, the method comprising the following steps:

[0041] The first step is to obtain the reflected power signal and the incident power signal of the medical cyclotron at a preset sampling frequency.

[0042] The incident power of a medical cyclotron is the power delivered from the RF power source to the accelerator cavity. It represents the total power delivered by the power source to the load. Reflected power, on the other hand, is the power reflected back due to a mismatch between the load and the power source. Ideally, if the load and power source are perfectly matched, all the incident power would be absorbed by the load, and the reflected power would be zero.

[0043] During actual measurement, this application uses a directional coupler and a power meter to perform measurements on the transmission line of a medical cyclotron. The directional coupler can separate the incident power and reflected power on the transmission line, and then use the power meter to measure these two powers. The specific measurement method is a well-known technology in the measurement field and will not be repeated here.

[0044] In this embodiment, the sampling frequency of the incident power and reflected power is set to 150 MHz, and the data storage duration is 10 microseconds. During this time period, the incident power and reflected power are both stored as vectors of length N. These two vectors are referred to as the incident power signal and the reflected power signal, respectively, where the nth element represents the incident power and reflected power value at the nth moment.

[0045] The second step is to use the reflected power at each moment as the central element to preset a window, and obtain the signal disorder value at each moment based on the spectrum difference of the reflected power signal on both sides of the central element.

[0046] When no spark occurs in a medical cyclotron, the incident power signal and reflected power signal of the medical cyclotron are usually relatively stable. The incident power is controlled by the power supply of the medical cyclotron and remains basically unchanged. However, there are various interference sources with impedance inside the resonant cavity of the medical cyclotron. The interference sources will generate reflected power with fixed frequency domain characteristics. Therefore, when no spark occurs, the reflected power signal is a signal with stable characteristics caused by the interference sources inside the resonant cavity.

[0047] When a spark occurs in a medical cyclotron, sparks are generated inside the resonant cavity. At this time, the acceleration device of the medical cyclotron suddenly short-circuits, causing the reflected power signal to suddenly increase and the frequency domain characteristics of the reflected power signal to change dramatically. At the same time, the incident power signal is still controlled by the power supply of the medical cyclotron and remains basically unchanged.

[0048] It can be concluded that if the reflected power signal at a certain element is the moment when an ignition event occurs, the difference between the spectrum in the left window and the spectrum in the right window reaches the maximum in a short period of time, and the spectrum in the right window is generally higher than the spectrum in the left window; based on this, the moment of signal disorder is obtained according to the changing characteristics of the reflected power signal when the ignition event occurs.

[0049] The reflected power signal is a real-time updated signal, with its Nth element representing the most recently measured reflected power. This embodiment uses the reflected power measured at the most recently measured moment and a preset number W of moments before that as a window. In this embodiment, the preset number W is 151, but can be adjusted by the implementer based on actual circumstances. The central element of this window is extracted, and the subwindow consisting of all elements before the central element is obtained is denoted as the left window of the central element. The subwindow consisting of all elements after the central element is obtained is denoted as the right window of the central element. The left and right windows represent the signal conditions on the left and right sides of the reflected power signal corresponding to the central element.

[0050] The Fourier transform algorithm is applied to the signals of the left window and the right window respectively, wherein the necessary parameters of the algorithm are: the frequency range is 0 to 150 MHz, the sampling frequency is 1 MHz, and the output is a spectrum diagram, which is recorded as the left window spectrum and the right window spectrum respectively. The data form of the spectrum is represented by a vector. In this embodiment, the vector length is W, wherein the mth element represents the signal energy amplitude at the mth frequency.

[0051] During operation of a medical cyclotron, the distance between the left and right window spectra of the reflected power at each moment is measured, with the reflected power at each moment as the central element. This distance is recorded as the signal disorder value at each moment, and is used to characterize the variation characteristics of the reflected power over a period of time before and after each moment. In this embodiment, the distance measurement uses Euclidean distance; implementers may choose other distance measurement methods, and this application does not impose any restrictions.

[0052] The third step: judging whether the corresponding moment is the moment when the ignition event occurs based on the distribution difference of the reflected power signals on both sides of the central element in the window corresponding to the moment when the signal disorder value in each window is the largest.

[0053] When a moment is the moment when the ignition event occurs or the moment when the ignition event ends, the corresponding signal disorder value is the largest, because only when one window on both sides of the window corresponding to the moment is completely the signal when the ignition is not started and the other window is completely the signal when the ignition is started, the spectrum difference between the windows is the largest, that is, the signal disorder value is the largest, and the corresponding moment is marked as the signal disorder moment; with the reflected power signal at the moment of signal disorder as the center, calculate the left window spectrum mean and the right window spectrum mean at this time. If the left window spectrum mean is smaller than the right window spectrum mean, it means that the signal energy amplitude of the left window is smaller, which means that the corresponding signal disorder moment is the moment when the ignition event occurs; otherwise, the corresponding signal disorder moment is the moment when the ignition event ends.

[0054] It should be understood that there are multiple signal disorder moments during the operation of the medical accelerator, and the signal disorder moments include the moment when the ignition event occurs and the moment when the ignition event ends.

[0055] The fourth step: according to the distribution of the reflected power signal in the window corresponding to the time when the ignition event occurs, the reflected power of the interference source at the time when the ignition event occurs is obtained.

[0056] The moment of signal disturbance can be used to preliminarily determine the start and end of a spark event, but it is not possible to determine the intensity of different spark events. The intensity of a spark event can be calculated based on the strength of the reflected power signal and the duration of the spark event. Therefore, the intensity of the spark event can be calculated based on the reflected power signal. However, in addition to the reflected power caused by the spark event, the reflected power signal also contains reflected power caused by internal interference sources within the medical cyclotron. Therefore, when using the reflected power signal to characterize the intensity of the spark event, this interference factor needs to be removed.

[0057] At the moment of the ignition event, the signal in the left window is generated by the internal interference source of the medical cyclotron. Therefore, this part of the signal can be used to calculate the reflected power of the interference source, thereby removing the influence of the interference source on the judgment of the intensity of the ignition event.

[0058] Therefore, when a spark event is detected, the left window at that moment is captured, and the average level of the reflected power signal within the left window is recorded as the interference source reflected power. In this embodiment, the average level of each data point is measured by calculating the mean. The interference source reflected power represents the average power of the interference source in the reflected signal and can be used to eliminate the influence of the interference source on the determination of the spark event intensity.

[0059] The fifth step: According to the number of signals in the window and the sampling frequency of the signal, the result lag time is obtained; based on the interference source reflection power at the moment corresponding to the result lag time before the ignition event occurs, combined with the reflection power signal at each moment, the ignition signal strength value is obtained.

[0060] In this embodiment, if we want to obtain the cyclotron state at time t, we need to obtain W-1 data collected before and after this time to determine whether time t is the time when the ignition event occurs. Since this embodiment uses a sliding window method to calculate the signal disorder value at each moment, the window length is set to 151 sampling points. Because the data sampling frequency is 150 MHz, the time interval between each sampling point is very short. Therefore, when calculating the signal disorder value based on the window, approximately seconds of delay, where W represents the window length, W-1 represents the number of time intervals in the window, and F represents the sampling frequency of the signal. The result is recorded as the result lag time. In this embodiment, the result lag time is 1 microsecond, that is, the result will lag behind the actual signal by 1 microsecond.

[0061] It should be noted that the size of the window in this embodiment has a certain correlation with the result lag time. If the window length is small, the delay time will be shorter, but it will result in fewer reflected power signal values being considered, which will produce a larger error. However, if the window length is larger, the lag time for obtaining the result will be longer. Therefore, the implementer can adjust the window length according to the actual situation. Since the traditional ignition event detection conditions corresponding to this embodiment are: reflected power>0.8×incident power, duration is 5 microseconds, that is, the ignition judgment coefficient is 0.8, and the ignition duration is 5 microseconds. The ignition time represents that only ignition events with a duration of 5 microseconds are ignition events that require the control device to react, so the result lag time in this application cannot exceed 5 microseconds. Among them, the ignition judgment coefficient and the ignition duration are both ignition event detection parameters.

[0062] Therefore, when calculating the ignition signal strength value, it is necessary to use the reflected power signal of the past result lag time as the initial calculation data for calculation: specifically, taking the tth moment as an example, the moment corresponding to the lag time of the result at the tth moment is detected to be the moment when the ignition event occurs, and the interference source reflected power at the tth moment is obtained. In the window centered on the tth moment, all elements of the reflected power signal at all moments after the tth moment are subtracted from the interference source reflected power, and recorded as the ignition power signal at each moment.

[0063] The sum of the ignition power signals from the moment the ignition event occurs to the current moment is used as the ignition signal strength value at the current moment. The larger the value, the greater the intensity of the ignition event that occurred from the tth moment to the current moment, and the more the ignition event should be responded to by the control system.

[0064] Among them, the flow chart for obtaining the ignition signal strength value is as follows: Figure 2 shown.

[0065] The sixth step: according to the ignition signal strength value, combined with the incident power signal at the current moment and the frequency of signal sampling, determine whether the medical cyclotron needs to enter the ignition response state.

[0066] An intensity threshold is set for the intensity of the ignition event. When the intensity of the ignition event is greater than the intensity threshold, it is considered that the intensity of the ignition event is too strong and measures should be taken. The intensity threshold is obtained by first presetting the ignition judgment coefficient d, which is 0.8 in this embodiment, and the ignition duration is recorded as T, which is 5 microseconds in this embodiment. Then, the incident power Pi at the current moment is obtained and the intensity threshold is calculated as , where F is the sampling frequency of the signal, which is 150 MHz in this embodiment.

[0067] The intensity threshold is based on traditional ignition event detection parameters and is obtained according to the calculation method of ignition event intensity. It is equivalent to mapping traditional ignition event detection parameters to the ignition event intensity. When the ignition event intensity is greater than the intensity threshold, it is considered that the ignition event occurring at this time is serious and the ignition event needs to be responded to by the control system.

[0068] In particular, when the moment corresponding to the result lag time before the current moment is judged to be the end moment of the ignition event, the system will no longer calculate the intensity of the ignition event until the next start moment of the ignition event is detected, and then re-judge the intensity of the ignition event.

[0069] Based on the same inventive concept as the above method, an embodiment of the present application also provides a medical cyclotron, including a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, the steps of any one of the above-mentioned medical cyclotron ignition protection methods are implemented.

[0070] In summary, the embodiment of the present application obtains the reflected power signal and the incident power signal of the medical cyclotron at a preset sampling frequency, provides a data basis for subsequent detection and analysis of ignition events, and understands the working state of the medical cyclotron when igniting; takes the reflected power at each moment as the central element to preset a window, and obtains the signal disorder value at each moment according to the spectrum difference of the reflected power signal on both sides of the central element, which helps to accurately screen out the start and end time of the ignition event of the medical cyclotron in the subsequent process; judges whether the corresponding moment is the moment of ignition event according to the distribution difference of the reflected power signal on both sides of the central element in the window corresponding to the moment when the signal disorder value in each window is the largest, obtains the accurate moment of ignition event, and improves the accuracy of subsequent control of ignition events; The distribution of the internal reflection power signal is used to obtain the interference source reflection power at the time of the ignition event, which helps to eliminate the influence of the medical cyclotron on the judgment of the intensity of the ignition event by using the reflection power signal when the ignition event does not occur. According to the number of signals in the window and the sampling frequency of the signal, the result lag time is obtained to characterize the delay of the calculation result relative to the actual time when the signal occurs. Based on the interference source reflection power at the time corresponding to the result lag time before the ignition event, combined with the reflection power signal at each time, the ignition signal strength value at the current time is obtained. The method of incorporating the power of the reflection power signal generated by the ignition event into the ignition event intensity judgment can more comprehensively consider the intensity differences of the ignition event at different times compared to the existing evaluation method that only relies on the duration of the ignition event. This method makes the evaluation of the intensity of the ignition event more accurate and improves the response sensitivity to the ignition event, thereby effectively protecting the medical cyclotron from potential damage.

[0071] The flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the systems, methods and computer program products according to the embodiments of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of the code, and the part of the module, program segment or code contains one or more executable instructions for realizing the specified logical function. In some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. In the description corresponding to the flowcharts and block diagrams in the accompanying drawings, the operations or steps corresponding to different boxes can also occur in an order different from that disclosed in the description, and sometimes there is no specific order between different operations or steps. For example, two consecutive operations or steps can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. Each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented by a dedicated hardware-based system that performs the specified function or action, or may be implemented by a combination of dedicated hardware and computer instructions.

[0072] It is obvious to those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and that the present application can be implemented in other specific forms without departing from the basic features of the present application. Therefore, from any point of view, the above embodiments of the present application should be regarded as exemplary and non-restrictive; modifications to the technical solutions described in the above embodiments, or equivalent replacement of some of the technical features therein, do not deviate from the essence of the corresponding technical solutions within the scope of the technical solutions of the embodiments of the present application, and should be included in the scope of protection of the present application.

Claims

1. A method for protecting a medical cyclotron from sparking, characterized in that: The method comprises the following steps: Acquire the reflected power signal and incident power signal of the medical cyclotron at a preset sampling frequency; The reflected power at each moment is used as the preset window of the central element, and the signal disorder value at each moment is obtained based on the spectrum difference of the reflected power signal on both sides of the central element; Based on the distribution difference of the reflected power signals on both sides of the central element in each window corresponding to the moment when the signal disorder value in each window is the largest, it is determined whether the corresponding moment is the moment when the ignition event occurs; According to the distribution of the reflected power signal in the window corresponding to the time when the ignition event occurs, the reflected power of the interference source at the time when the ignition event occurs is obtained; The result lag time is obtained based on the number of signals in the window and the sampling frequency of the signal; the ignition signal strength value is obtained based on the interference source reflection power at the time corresponding to the result lag time before the ignition event occurs, combined with the reflection power signal at each time; According to the ignition signal strength value, combined with the incident power signal at the current moment and the signal sampling frequency, it is determined whether the medical cyclotron needs to enter the ignition response state.

2. A medical cyclotron spark protection method according to claim 1, characterized in that: The signal disorder value at each moment is obtained as follows: In the window corresponding to the reflected power signal at each moment, the sub-window consisting of the elements at all moments before the moment when the central element in the window is obtained is recorded as the left window; the sub-window consisting of the elements at all moments after the moment when the central element in the window is obtained is recorded as the right window; The spectrum corresponding to the reflected power signal in the left window and the right window is recorded as the left window spectrum and the right window spectrum respectively; The distance between the left window spectrum and the right window spectrum of the reflected power signal at each moment is measured and recorded as the signal disorder value at each moment.

3. A medical cyclotron spark protection method according to claim 2, characterized in that: The determination of whether the corresponding moment is the moment when the ignition event occurs is specifically as follows: In the window corresponding to the filtered moment, obtain the left window spectrum mean and the right window spectrum mean; if the left window spectrum mean is less than the right window spectrum mean, it is determined that the corresponding moment is the moment when the ignition event occurs.

4. A medical cyclotron spark protection method according to claim 2, characterized in that: The process of obtaining the interference source reflected power at the time when the ignition event occurs includes: In the window corresponding to the time when the ignition event occurs, the average level of the reflected power signal in the left window is used as the interference source reflected power at the time when the ignition event occurs.

5. The method for protecting a medical cyclotron from sparking as claimed in claim 1, wherein: The result lag time is specifically the ratio of the number of time intervals in the window to the signal sampling frequency; wherein the number of time intervals in the window is determined by the difference between the number of sampling points in the window and 1.

6. A medical cyclotron spark protection method according to claim 2, characterized in that: The process of determining whether to obtain the ignition signal strength value includes: If the spectrum mean of the left window is less than or equal to the spectrum mean of the right window in all windows between the time when the ignition event occurs and the current time, calculate the ignition signal strength value at the current time; Otherwise, the ignition signal strength value at the current moment is not calculated, and the ignition signal strength value is calculated until the next ignition event occurs.

7. A medical cyclotron spark protection method according to claim 6, characterized in that: The calculation of the ignition signal strength value at the current moment includes: The ignition power signal at each moment is obtained based on the difference between the reflected power signal at each moment after the ignition event occurs and the interference source reflected power at the moment corresponding to the result lag time before the ignition event occurs; The accumulated sum of the ignition power signals from the time the ignition event occurs to the current time is taken as the ignition signal strength value at the current time.

8. The method for protecting a medical cyclotron from sparking as claimed in claim 1, wherein: The determination of whether the medical cyclotron needs to enter the ignition response state is specifically as follows: An intensity threshold is obtained based on the incident power signal at the current moment in combination with the signal sampling frequency; if the intensity of the ignition event is greater than the intensity threshold, it is determined that the medical cyclotron needs to enter the ignition response state.

9. A medical cyclotron spark protection method according to claim 8, characterized in that: The formula for the intensity threshold is: , where LM is the intensity threshold, F is the sampling frequency of the signal, d is the preset ignition judgment coefficient, Pi is the incident power at the current moment, and T is the ignition duration.

10. A medical cyclotron comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 9 are implemented.

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