Medical cyclotron and ignition protection method

Abstract

The invention relates to the technical field of accelerators, in particular to a medical cyclotron and an ignition protection method, and the method comprises the steps: obtaining a reflection power signal and an incident power signal of the medical cyclotron at a preset sampling frequency; presetting a window, and obtaining a signal disorder value according to the signal difference of the reflection power; judging whether the moment with the maximum signal disorder value is the ignition event occurrence moment or not; interference source reflection power is obtained according to distribution of reflection power signals in the window corresponding to the ignition event occurrence moment; obtaining a result lag time length; obtaining an ignition signal intensity value at the current moment by combining the reflection power signal at each moment; and in combination with the incident power signal and the signal sampling frequency, whether the medical cyclotron needs to enter an ignition response state or not is judged. According to the method, the power of the reflection power signal is included in ignition event intensity judgment, the ignition intensity is evaluated more accurately, the response sensitivity is improved, and the medical cyclotron is protected.

Description

Technical Field

[0001] This application relates to the technical field of accelerators, and particularly to a medical cyclotron and a spark protection method. Background Art

[0002] In a medical cyclotron, the detection and handling of sparking phenomena are crucial for ensuring the safe operation of the device. Sparking usually refers to abnormal discharges caused by unclean cavity surfaces, insufficient vacuum, or other reasons under the action of a high-frequency electric field. Such discharges can cause instantaneous reflections of radio frequency power, damaging the electronic devices of the accelerator. During the use of a medical cyclotron, the occurrence of sparking is detected based on a sharp drop in the cavity signal. When sparking occurs, the control system will respond quickly and control the radio frequency switch to turn off hardware, thereby cutting off the radio frequency excitation to achieve hardware protection.

[0003] However, not all sparking phenomena require immediate shutdown of the accelerator. Some instantaneous sparking may not damage the accelerator. Therefore, if the duration of the sparking is not long, it may not be judged as a sparking phenomenon that requires immediate action. This requires the spark protection system to accurately detect the start and end of the sparking phenomenon to avoid unnecessary shutdowns and maintenance.

[0004] Current methods usually rely on setting empirical thresholds for input power and reflected power to detect sparking events and evaluate the severity of sparking through a fixed detection time, and only take action when the sparking situation is severe. This method only judges the severity of sparking based on the detection time and does not fully consider the power differences of different sparking events, which may lead to inaccurate evaluation of the sparking situation, resulting in insensitive spark protection response and damage to the medical cyclotron. Summary of the Invention

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

[0006] The first aspect of this application provides a spark protection method for a medical cyclotron, and the method includes: Obtaining the reflected power signal and incident power signal of the medical cyclotron at a preset sampling frequency; Taking the reflected power at each moment as the central element to preset a window, and obtaining the signal disorder value at each moment according to the spectral difference of the reflected power signals on both sides of the central element; Judging whether the corresponding moment is the occurrence moment of a sparking event according to the distribution difference of the reflected power signals on both sides of the central element within the window corresponding to the moment with the largest signal disorder value in each window; According to the distribution of the reflected power signal within the window corresponding to the occurrence time of the sparking event, the reflected power of the interference source at the occurrence time of the sparking event is obtained; According to the number of signals in the window and the sampling frequency of the signals, the result lag duration is obtained; based on the reflected power of the interference source at the time corresponding to the result lag duration before the occurrence time of the sparking event, and combined with the reflected power signals at each time, the sparking signal intensity value is obtained; According to the sparking signal intensity value, combined with the incident power signal at the current time and the signal sampling frequency, it is judged whether the medical cyclotron needs to enter the sparking response state.

[0007] Among them, the obtaining of the signal disorder value at each time is specifically as follows: In the window corresponding to the reflected power signal at each time, the sub-window composed of the elements at all times before the time of obtaining the central element in the window is denoted as the left window; the sub-window composed of the elements at all times after the time of obtaining the central element in the window is denoted as the right window; The spectra corresponding to the reflected power signals in the left window and the right window are respectively denoted as the left window spectrum and the right window spectrum; The distance metric between the left window spectrum and the right window spectrum of the reflected power signal at each time is denoted as the signal disorder value at each time.

[0008] Among them, the judgment of whether the corresponding time is the occurrence time of the sparking event is specifically as follows: In the window corresponding to the selected time, the left window spectrum mean value and the right window spectrum mean value are obtained; if the left window spectrum mean value is less than the right window spectrum mean value, it is judged that the corresponding time is the occurrence time of the sparking event.

[0009] Among them, the process of obtaining the reflected power of the interference source at the occurrence time of the sparking event includes: In the window corresponding to the occurrence time of the sparking event, the average level of the reflected power signal in the left window is used as the reflected power of the interference source at the occurrence time of the sparking event.

[0010] Among them, the result lag duration is specifically the ratio of the number of time intervals of the window to the signal sampling frequency; among them, the number of time intervals of the window is determined by the difference between the number of sampling points in the window and 1.

[0011] Among them, the process of judging whether to obtain the sparking signal intensity value includes: If the left window spectrum mean value is less than or equal to the right window spectrum mean value in the windows at all times between the occurrence time of the sparking event and the current time, calculate the sparking signal intensity value at the current time; Otherwise, do not calculate the sparking signal intensity value at the current time until the occurrence time of the next sparking event, and calculate the sparking signal intensity value.

[0012] Among them, calculating the intensity value of the spark signal at the current moment includes: Obtaining the spark power signal at each moment according to the difference between the reflected power signal at each moment after the occurrence moment of the spark event and the interference source reflected power at the moment corresponding to the result lag duration before the occurrence moment of the spark event; Taking the sum of the spark power signals from the occurrence moment of the spark event to the current moment as the intensity value of the spark signal at the current moment.

[0013] Among them, judging whether the medical cyclotron needs to enter the spark response state specifically is: Obtaining an intensity threshold according to the incident power signal at the current moment in combination with the signal sampling frequency; if the intensity of the spark event is greater than the intensity threshold, it is judged that the medical cyclotron needs to enter the spark response state.

[0014] Among them, the formula for the intensity threshold is: , where LM is the intensity threshold, F is the sampling frequency of the signal, d is a preset spark judgment coefficient, Pi is the incident power at the current moment, and T is the spark duration.

[0015] In a second aspect, an embodiment of the present application further 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 the method described in any one of the above are implemented.

[0016] In the above solution, the reflected power signal and incident power signal of the medical cyclotron are acquired at a preset sampling frequency, providing a data basis for subsequent detection and analysis of the sparking event and helping to understand the working state of the medical cyclotron during sparking. Windows are preset with the reflected power at each moment as the central element. According to the spectral differences of the reflected power signals on both sides of the central element, the signal disorder value at each moment is obtained, which helps to accurately screen the start and end moments of the sparking event in the medical cyclotron in the subsequent process. According to the distribution differences of the reflected power signals on both sides of the central element within 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 when the sparking event occurs, and the accurate moment when the sparking event occurs is obtained, improving the accuracy of subsequent control of the sparking event. According to the distribution of the reflected power signal within the window corresponding to the moment when the sparking event occurs, the reflected power of the interference source at the moment when the sparking event occurs is obtained, which helps to eliminate the influence of the medical cyclotron on the judgment of the sparking event intensity by using the reflected power signal when the sparking event does not occur in the subsequent process. According to the number of signals in the window and the sampling frequency of the signals, the result lag duration is obtained, which depicts the delay of the calculation result relative to the actual occurrence moment of the signal. Based on the reflected power of the interference source at the moment corresponding to the result lag duration before the moment when the sparking event occurs, combined with the reflected power signals at each moment, the sparking signal intensity value at the current moment is obtained. Incorporating the power magnitude of the reflected power signal generated by the sparking event into the method for judging the sparking event intensity can, compared with the existing evaluation method that only relies on the duration of the sparking event, more comprehensively consider the intensity differences of the sparking event at different moments. This method makes the evaluation of the sparking event intensity more accurate, improves the response sensitivity to the sparking event, and thus effectively protects the medical cyclotron from potential damage. Description of the Drawings

[0017] Figure 1 It is a flowchart of the steps of a method for protecting a medical cyclotron from sparking provided by an embodiment of the present application; Figure 2 It is a flowchart for obtaining the sparking signal intensity value provided by an embodiment of the present application. Detailed Embodiments

[0018] In the description of the embodiments of the present application, words such as "exemplary", "or", "for example" are used to represent examples, illustrations or explanations. Any embodiment or design solution described as "exemplary" or "for example" in the embodiments of the present application should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Exactly speaking, using words such as "exemplary", "or", "for example" aims to present relevant concepts in a specific way.

[0019] Unless otherwise defined, 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. The terms used in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0020] In addition, it should be noted that the terms "first" and "second" in this application and the accompanying drawings are used to distinguish similar objects and are not used to describe a specific order or sequence. For the methods disclosed in the embodiments of this application or shown in the flowcharts of the methods, which include one or more steps for implementing the methods, without departing from the scope of protection of this application, the execution order of multiple steps can be interchanged with each other, and some steps can also be deleted.

[0021] Unless otherwise defined, 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.

[0022] The following specifically describes the specific solutions of a medical cyclotron and a spark protection method provided by this application with reference to the accompanying drawings.

[0023] Please refer to Figure 1 , which shows a flowchart of the steps of a medical cyclotron spark protection method provided by an embodiment of this application. The method includes the following steps: The first step: Obtain the reflected power signal and the incident power signal of the medical cyclotron at a preset sampling frequency.

[0024] The incident power of the medical cyclotron refers to the power transmitted from the RF power source to the accelerator cavity, which represents all the power provided by the power supply to the load; while the reflected power refers to the part of the power reflected back due to the mismatch between the load and the power supply. In an ideal situation, if the load and the power supply are completely matched, then all the incident power will be absorbed by the load and the reflected power will be zero.

[0025] In actual measurement, this application uses a directional coupler and a power meter to measure on the transmission line of the medical cyclotron. The directional coupler can separate the incident power and the 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 elaborated here.

[0026] In this embodiment, the sampling frequencies of the incident power and the reflected power are set to 150 MHz, and the data storage time length is 10 microseconds. During this time period, the incident power and the reflected power are both stored as vectors of length N, and these two vectors are respectively called the incident power signal and the reflected power signal. Among them, the nth element represents the incident power and the reflected power values at the nth moment.

[0027] Second step: Preset a window with the reflected power at each moment as the central element, and obtain the signal disorder value at each moment according to the spectral difference of the reflected power signals on both sides of the central element.

[0028] When there is no sparking event in the medical cyclotron, the incident power signal and the 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. There are various impedance interference sources inside the resonant cavity of the medical cyclotron, and the interference sources will generate reflected power with fixed frequency domain characteristics. Therefore, when there is no sparking, the reflected power signal is a signal with stable characteristics caused by the interference sources inside the resonant cavity.

[0029] When a sparking event occurs in the medical cyclotron, a spark is generated inside the resonant cavity. At this time, the acceleration device of the medical cyclotron suddenly shorts, resulting in a sudden increase in the reflected power signal and a drastic change in the frequency domain characteristics of the reflected power signal. At the same time, the incident power signal is still controlled by the power supply of the medical cyclotron and remains basically unchanged.

[0030] From this, it can be obtained that if the reflected power signal at a certain element is the occurrence moment of a sparking event, the spectrum difference between the left window and the right window reaches the maximum within a short time, and the spectrum of the right window is generally higher than that of the left window. Based on this, according to the change characteristics of the reflected power signal when a sparking event occurs, the signal disorder moment is obtained.

[0031] The reflected power signal is a real-time updated signal. Its Nth element represents the reflected power measured at the most recent moment. In this embodiment, the reflected powers measured at the most recent moment and the previous total of preset number W of moments are used as a window. In this embodiment, the preset number W is taken as 151, and the implementer can adjust it according to the actual situation. Extract the central element of this window, and denote the sub-window composed of all elements before the acquisition moment of the central element in the window as the left window of the central element; denote the sub-window composed of all elements after the acquisition moment of the central element in the window as the right window of the central element. Among them, the left window and the right window represent the signal conditions on both sides of the reflected power signal corresponding to the central element.

[0032] The Fourier transform algorithm is respectively used for the signals of the left window and the right window. The necessary parameters of the algorithm are: the frequency range is taken from 0 to 150 MHz, the sampling frequency is 1 MHz, and the output is a spectrogram, which are respectively denoted as the left window spectrum and the right window spectrum. The data form of the spectrum is represented by a vector. In this embodiment, the vector length is W, where the mth element represents the signal energy amplitude at the mth frequency.

[0033] When the medical cyclotron is operating, taking the reflected power at each moment as the central element, the distance metric between the left-window spectrum and the right-window spectrum of the reflected power at each moment is denoted as the signal disorder value at each moment, which is used to characterize the change characteristics of the reflected power during a period of time before and after each moment. In this embodiment, the distance metric uses the Euclidean distance; the implementer can select other distance metric methods, and this application does not limit this.

[0034] The third step: According to the distribution difference of the reflected power signals on both sides of the central element in the window corresponding to the moment with the largest signal disorder value in each window, determine whether the corresponding moment is the occurrence moment of the sparking event.

[0035] When a moment is the occurrence moment or the end moment of the sparking event, the corresponding signal disorder value is the largest, because only when one window of the corresponding two windows is completely the signal when there is no sparking and the other window is completely the signal when there is sparking, the spectral 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; taking the reflected power signal at the signal disorder moment as the center, calculate the left-window spectrum mean value and the right-window spectrum mean value at this time. If the left-window spectrum mean value is less than the right-window spectrum mean value, it means that the signal energy amplitude of the left window is smaller, then it represents that the corresponding signal disorder moment is the occurrence moment of the sparking event; otherwise, the corresponding signal disorder moment is the end moment of the sparking event.

[0036] It should be understood that during the operation of the medical accelerator, there are multiple signal disorder moments, and the signal disorder moments include the occurrence moment of the sparking event and the end moment of the sparking event.

[0037] The fourth step: According to the distribution of the reflected power signal in the window corresponding to the occurrence moment of the sparking event, obtain the reflected power of the interference source at the occurrence moment of the sparking event.

[0038] The start and end of the sparking event can be preliminarily judged through the signal disorder moment, but the intensity of different sparking events cannot be judged; the intensity of the sparking event can be calculated through the intensity of the reflected power signal and the duration of the sparking event. Therefore, the intensity of the sparking event can be calculated according to the reflected power signal. However, in the reflected power signal, in addition to the reflected power caused by the sparking event, there is also the reflected power caused by the internal interference source of the medical cyclotron. Therefore, when using the reflected power signal to characterize the intensity of the sparking event, this part of the interference factor needs to be removed.

[0039] At the occurrence moment of the sparking 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, and further remove the influence of the interference source on the judgment of the intensity of the sparking event.

[0040] Therefore, when a moment of a sparking event is detected, the left window corresponding to that moment is obtained, and the average level of the reflected power signal within the left window is denoted as the reflected power of the interference source. In this embodiment, the average level of each data is measured by calculating the mean value. The reflected power of the interference source represents the average power magnitude caused by the interference source in the reflected signal, and can be used to remove the influence of the interference source on the judgment of the intensity of the sparking event.

[0041] The fifth step: Obtain the result lag duration according to the number of signals in the window and the sampling frequency of the signals; based on the reflected power of the interference source at the moment corresponding to the result lag duration before the moment of the sparking event, and combined with the reflected power signals at each moment, obtain the sparking signal intensity value.

[0042] In this embodiment, if the state of the cyclotron at the t-th moment is to be obtained, it is also necessary to obtain W - 1 data collected before and after that moment to determine whether the t-th moment is the moment when a sparking 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 sampling frequency of the data is 150 megahertz and the time interval between each sampling point is very short, when calculating the signal disorder value according to the window, a delay of approximately seconds will be introduced. Here, W represents the window length, W - 1 represents the number of time intervals in the window, F represents the sampling frequency of the signal, and the result is denoted as the result lag duration. In this embodiment, the result lag duration is 1 microsecond, that is, the result will lag behind the actual signal by 1 microsecond.

[0043] It should be noted that in this embodiment, there is a certain relationship between the size of the window and the result lag duration. If the window length is small, the delay time will be shorter, but it will result in fewer reflected power signal values being considered, and a larger error will be generated; 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 detection condition for the sparking event corresponding to this embodiment is: the reflected power > 0.8 × the incident power, and the duration is 5 microseconds, that is, the sparking judgment coefficient is taken as 0.8 and the sparking duration is taken as 5 microseconds. Among them, the sparking time represents that only a sparking event with a duration of 5 microseconds is a sparking event that requires the control device to react. Therefore, the result lag duration in this application cannot exceed 5 microseconds. Among them, both the sparking judgment coefficient and the sparking duration are sparking event detection parameters.

[0044] Therefore, when calculating the ignition signal strength value, the reflected power signal with the past result lag duration needs to be used as the initial calculation data for calculation: Specifically, taking the t-th moment as an example, at the moment corresponding to the result lag duration after the t-th moment, it is detected that the t-th moment is the occurrence moment of the ignition event, and the reflected power of the interference source at the t-th moment is obtained. In the window centered on the t-th moment, all elements of the reflected power signals at all moments after the t-th moment are respectively subtracted from the reflected power of the interference source, and are recorded as the ignition power signals at each moment.

[0045] From the occurrence moment of the ignition event to the current moment, sum the ignition power signals, which 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 during the time from the t-th moment to the current moment, and the more the ignition event should be responded to by the control system.

[0046] Among them, the flow chart for obtaining the ignition signal strength value is as Figure 2 shown.

[0047] The sixth step: According to the ignition signal strength value, combined with the incident power signal at the current moment and the signal sampling frequency, determine whether the medical cyclotron needs to enter the ignition response state.

[0048] Set an intensity threshold for the ignition event intensity. When the ignition event intensity is greater than the intensity threshold, it is considered that the intensity of this ignition event is too large and measures should be taken. Among them, the method for obtaining the intensity threshold is as follows: First, preset an ignition judgment coefficient d, which is taken as 0.8 in this embodiment, and the ignition duration is denoted as T, which is taken as 5 microseconds in this embodiment. Further obtain the incident power Pi at the current moment, and calculate the intensity threshold as , where F is the signal sampling frequency, which is taken as 150 MHz in this embodiment.

[0049] The intensity threshold is obtained based on the traditional ignition event detection parameters according to the calculation method of the ignition event intensity, which is equivalent to mapping the 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.

[0050] Particularly, when the moment corresponding to the result lag duration before the current moment is judged to be the end moment of the ignition event, the system no longer calculates the ignition event intensity until the start moment of the next detected ignition event, and then re-judges the intensity of the ignition event.

[0051] Based on the same inventive concept as the above method, an embodiment of the present application further 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 methods for the fire protection method of a medical cyclotron are implemented.

[0052] In summary, the embodiment of the present application acquires the reflected power signal and incident power signal of the medical cyclotron at a preset sampling frequency, providing a data basis for subsequent detection and analysis of the fire event and understanding the working state of the medical cyclotron during a fire; a window is preset with the reflected power at each moment as the central element, and according to the spectral difference of the reflected power signals on both sides of the central element, the signal disorder value at each moment is obtained, which helps to accurately screen out the start and end moments of the fire event of the medical cyclotron in the future; according to the distribution difference of the reflected power signals 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 occurrence moment of the fire event, and the accurate occurrence moment of the fire event is obtained, improving the accuracy of subsequent control of the fire event; according to the distribution of the reflected power signal in the window corresponding to the occurrence moment of the fire event, the reflected power of the interference source at the occurrence moment of the fire event is obtained, which helps to eliminate the influence of the medical cyclotron on the judgment of the fire event intensity by using the reflected power signal when the fire event does not occur in the future; according to the number of signals in the window and the sampling frequency of the signals, the result lag duration is obtained, which describes the delay of the calculation result relative to the actual occurrence moment of the signal; based on the reflected power of the interference source at the moment corresponding to the result lag duration before the occurrence moment of the fire event, combined with the reflected power signals at each moment, the fire signal intensity value at the current moment is obtained; the power magnitude of the reflected power signal generated by the fire event is incorporated into the method for judging the fire event intensity. Compared with the existing evaluation method that only relies on the duration of the fire event, it can more comprehensively consider the intensity differences of the fire event at different moments. This method makes the evaluation of the fire event intensity more accurate, improves the response sensitivity to the fire event, and thus effectively protects the medical cyclotron from potential damage.

[0053] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to embodiments of the present application. In this regard, each box in the flowchart or block diagram may represent a module, a segment of a program, or a portion of code that contains one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions noted in the boxes may occur in a different order than noted in the accompanying drawings. For example, two consecutive boxes may actually be executed substantially in parallel, or they may sometimes be executed in reverse order, depending on the functions involved. In the descriptions corresponding to the flowcharts and block diagrams in the accompanying drawings, the operations or steps corresponding to different boxes may also occur in a different order than disclosed in the description, and sometimes there is no specific order between different operations or steps. For example, two consecutive operations or steps may actually be executed substantially in parallel, or they may sometimes be executed in reverse order, depending on the functions involved. Each box in the block diagram and / or flowchart, as well as combinations of boxes in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system that performs the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

[0054] For those skilled in the art, it is obvious that the present application is not limited to the details of the above-described exemplary embodiments, and that the present application can be implemented in other specific forms without departing from the basic characteristics of the present application. Therefore, from any point of view, the above-described embodiments of the present application should be regarded as exemplary and non-restrictive; modifications to the technical solutions described in the foregoing embodiments, or equivalent replacements of some of the technical features, do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application, and should all be included within the protection scope of the present application.

Claims

1. A method for protecting a medical cyclotron from sparking, characterized in that, The method includes the following steps: Obtain the reflected power signal and incident power signal of the medical cyclotron at a preset sampling frequency; Preset a window with the reflected power at each moment as the central element, and obtain the signal disorder value at each moment according to the spectral difference of the reflected power signals on both sides of the central element; Judge whether the corresponding moment is the occurrence moment of the sparking event according to the distribution difference of the reflected power signals on both sides of the central element in the window corresponding to the moment with the largest signal disorder value in each window; Obtain the reflected power of the interference source at the occurrence moment of the sparking event according to the distribution of the reflected power signal in the window corresponding to the occurrence moment of the sparking event; Obtain the result lag duration according to the number of signals in the window and the sampling frequency of the signals; based on the reflected power of the interference source at the moment corresponding to the result lag duration before the occurrence moment of the sparking event, and combined with the reflected power signals at each moment, obtain the sparking signal intensity value; Judge whether the medical cyclotron needs to enter the sparking response state according to the sparking signal intensity value, combined with the incident power signal at the current moment and the signal sampling frequency.

2. The method for protecting a medical cyclotron from arcing according to claim 1, wherein, The obtaining of the signal disorder value at each moment is specifically as follows: In the window corresponding to the reflected power signal at each moment, the sub-window composed of the elements at all moments before the moment of obtaining the central element in the window is denoted as the left window; the sub-window composed of the elements at all moments after the moment of obtaining the central element in the window is denoted as the right window; Respectively denote the spectra corresponding to the reflected power signals in the left window and the right window as the left window spectrum and the right window spectrum; Denote the distance metric between the left window spectrum and the right window spectrum of the reflected power signal at each moment as the signal disorder value at each moment.

3. The method for protecting a medical cyclotron from sparking according to claim 2, characterized in that, The judging whether the corresponding moment is the occurrence moment of the sparking event is specifically as follows: In the window corresponding to the selected moment, obtain the left window spectrum mean value and the right window spectrum mean value; if the left window spectrum mean value is less than the right window spectrum mean value, judge that the corresponding moment is the occurrence moment of the sparking event.

4. The method for protecting a medical cyclotron from sparking according to claim 2, wherein, The process of obtaining the reflected power of the interference source at the occurrence moment of the sparking event includes: In the window corresponding to the occurrence moment of the sparking event, use the average level of the reflected power signal in the left window as the reflected power of the interference source at the occurrence moment of the sparking event.

5. The medical cyclotron spark protection method according to claim 1, wherein The result lag duration is specifically the ratio of the number of time intervals of the window to the signal sampling frequency; among them, the number of time intervals of the window is determined by the difference between the number of sampling points in the window and 1.

6. The method for protecting a medical cyclotron from sparking according to claim 2, wherein, The process of judging whether to obtain the sparking signal intensity value includes: If the left window spectrum mean value is less than or equal to the right window spectrum mean value in all windows at all moments from the occurrence moment of the sparking event to the current moment, calculate the sparking signal intensity value at the current moment; Otherwise, do not calculate the sparking signal intensity value at the current moment until the next occurrence moment of the sparking event appears, and then calculate the sparking signal intensity value.

7. A method for protecting a medical cyclotron from sparking according to claim 6, characterized in that, The calculating of the sparking signal intensity value at the current moment includes: Obtain the sparking power signal at each moment according to the difference between the reflected power signals at each moment after the occurrence moment of the sparking event and the reflected power of the interference source at the moment corresponding to the result lag duration before the occurrence moment of the sparking event; Take the sum of the ignition power signals from the moment of the ignition event to the current moment as the ignition signal intensity value at the current moment.

8. The method for protecting a medical cyclotron from sparking according to claim 1, wherein The judgment on whether the medical cyclotron needs to enter the ignition response state is specifically as follows: Based on the incident power signal at the current moment and combined with the signal sampling frequency, obtain the intensity threshold; if the ignition event intensity is greater than the intensity threshold, it is determined that the medical cyclotron needs to enter the ignition response state.

9. A method for protecting a medical cyclotron from arcing, as claimed in claim 8, wherein, The formula for the intensity threshold is as follows: , where LM is the intensity threshold, F is the sampling frequency of the signal, d is a preset ignition determination 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, it implements the steps of the method according to any one of claims 1-9.

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