Ion cyclotron interface coupling method

Abstract

The application discloses an ion cyclotron interface coupling method, and relates to the technical field of magnetized plasma radio frequency coupling. The method comprises the following steps: determining a plurality of discrete parameter combinations comprising a first ion proportion, a background magnetic field, an electron density profile and a tangential wave number component; for each discrete parameter combination, screening a candidate angular frequency based on an interface matching matrix corresponding to the candidate angular frequency, a normal wave number at a normal position in a density transition layer and an ion-ion hybrid margin to obtain a bound operating point frequency corresponding to the discrete parameter combination and construct a relationship table accordingly; and adjusting a vacuum-plasma device and / or a radio frequency source based on the relationship table during operation of the vacuum-plasma device. The method solves the problem that ion cyclotron interface coupling cannot be accurately realized, and realizes accurate identification of an interface bound state and precise regulation and control of ion cyclotron interface coupling.

Description

Technical Field

[0001] This application relates to the field of magnetized plasma radio frequency coupling technology, and in particular to an ion cyclotron interface coupling method. Background Technology

[0002] An ion cyclotron resonance heating system typically consists of a radio frequency source, a transmission line, a matching network, and an antenna. The antenna is installed outside the plasma boundary. The radio frequency wave generated by the radio frequency source passes through the antenna, passes through the vacuum region, and enters the magnetized plasma. The antenna current has a certain spectral width in the tangential wavenumber space.

[0003] Currently, the frequency and matching network parameters are mainly selected based on the reflection coefficient, voltage standing wave ratio, loading resistance, or port received power. However, the peak value in the port loading spectrum does not uniquely correspond to the interface bound state. Antenna self-resonance, ion cyclotron poles, ion-ion hybrid layers, mode conversion of bulk propagation waves, standing waves caused by finite computational regions, and spectral broadening caused by collisions can all produce similar loading peaks. If identification is based solely on loading peaks or reflection phases, it is easy to misjudge bulk resonances or numerical pseudo-modes as interface states. Moreover, the received power measured at the port cannot be directly regarded as particle heating power. Without complete power balance and particle dynamics diagnosis, the port power cannot be interpreted as particle heating power, affecting the accurate identification of interface bound states and the accurate assessment of heating power. Summary of the Invention

[0004] This application provides an ion cyclotron interface coupling method, which aims to improve the problem in related technologies where the peaks in the port loading spectrum do not uniquely correspond to the interface bound states, making it easy to misjudge bulk resonances or numerical pseudo-modes as interface states when identifying them based solely on loading peaks or reflection phases, thus failing to accurately achieve ion cyclotron interface coupling.

[0005] To achieve the above objectives, a first aspect of this application proposes an ion cyclotron interface coupling method, comprising: determining multiple discrete parameter combinations, wherein each discrete parameter combination includes a first ion ratio of a vacuum-plasma device, a background magnetic field and an electron density profile, and a tangential wavenumber component of a radio frequency wave emitted by a radio frequency source; substituting candidate angular frequencies and discrete parameter combinations into the propagation equation to obtain the interface matching matrix corresponding to the candidate angular frequency and the normal wavenumber at the normal position within the density transition layer; substituting the candidate angular frequencies into the cold magnetized plasma dielectric tensor to obtain the transverse diagonal parameter at the normal position within the density transition layer corresponding to the candidate angular frequency, and based on... The lateral diagonal parameters are used to calculate the ion-ion hybridization margin corresponding to the candidate angular frequencies. Candidate angular frequencies are then screened based on the interface matching matrix, normal wavenumber, and ion-ion hybridization margin, and those meeting preset screening conditions are determined as the bound operating point frequencies corresponding to the discrete parameter combinations. A relationship table is constructed based on the bound operating point frequencies corresponding to the discrete parameter combinations, where the relationship table characterizes the correspondence between the bound operating point frequencies and the first ion ratio, background magnetic field, electron density profile, and tangential wavenumber components. During the operation of the vacuum-plasma device, the vacuum-plasma device and / or radio frequency source are controlled based on the relationship table.

[0006] According to one embodiment of this application, controlling a vacuum-plasma device and / or a radio frequency (RF) source based on a relational table includes: acquiring the actual first ion ratio, actual background magnetic field, and actual electron density profile of the vacuum-plasma device; searching the relational table based on the actual first ion ratio, actual background magnetic field, and actual electron density profile of the vacuum-plasma device to obtain the target confinement operating point frequency and the target tangential wavenumber component; adjusting the driving frequency of the RF source based on the target confinement operating point frequency in response to the absolute value of the frequency difference between the actual driving frequency of the RF source and the target confinement operating point frequency being greater than a preset frequency threshold; and adjusting the antenna spectrum center of the RF source based on the target tangential wavenumber component in response to the absolute value of the tangential wavenumber component deviation between the tangential wavenumber component corresponding to the antenna spectrum center of the RF source and the target tangential wavenumber component being greater than a preset deviation threshold.

[0007] According to one embodiment of this application, the ion cyclotron interface coupling method further includes: obtaining the magnetic field margin, bulk spectrum isolation margin, ion-ion hybridization margin, and minimum bulk wave attenuation constant of the vacuum-plasma device; in response to the magnetic field margin being greater than a preset magnetic field margin threshold, the bulk spectrum isolation margin being greater than a preset bulk spectrum isolation threshold, the minimum bulk wave attenuation constant being less than a preset attenuation constant threshold, or the ion-ion hybridization margin being less than a preset ion-ion hybridization margin threshold, reducing the radio frequency power of the radio frequency source, and reselecting the target confinement operating point frequency, target tangential wavenumber component, target background magnetic field, and target first ion ratio based on a relational table; adjusting the driving frequency of the radio frequency source based on the target confinement operating point frequency, adjusting the antenna spectrum center of the radio frequency source based on the target tangential wavenumber component, and adjusting the vacuum-plasma device based on the target background magnetic field and the target first ion ratio.

[0008] According to one embodiment of this application, after constructing a relation table based on the bound operating point frequencies corresponding to the discrete parameter combinations, the method further includes: obtaining a first ion ratio in the discrete parameter combinations and determining the operating critical magnetic field corresponding to the first ion ratio; and deleting the discrete parameter combinations from the relation table in response to the fact that the background magnetic field in the discrete parameter combinations is less than the sum of the operating critical magnetic field and the preset magnetic field margin.

[0009] According to one embodiment of this application, determining the operating critical magnetic field corresponding to a first ion ratio includes: acquiring multiple background magnetic fields corresponding to the first ion ratio, and filtering out background magnetic fields with bound operating point frequencies from the multiple background magnetic fields; determining the minimum background magnetic field among the background magnetic fields with bound operating point frequencies as the operating critical magnetic field corresponding to the first ion ratio.

[0010] According to one embodiment of this application, the preset screening conditions include: the minimum singular value of the interface matching matrix is ​​less than or equal to a first preset threshold; the number of volume propagation channels of the real normal wavenumber in the normal wavenumber at the normal position in the density transition layer is zero; and the ion-ion mixing margin of the density transition layer is greater than or equal to a second preset threshold.

[0011] According to one embodiment of this application, the process of constructing the propagation equation includes: dividing the computational region into multiple discrete locations along the normal of the vacuum-plasma device according to the normal discrete step length, wherein the computational region includes a density transition layer, which is used to characterize the region where the electron density gradually increases from the boundary of the vacuum-plasma device to the plasma center; substituting the plasma parameters at each discrete location into the multi-component Maxwell-fluid equation to obtain the propagation equation at the corresponding discrete location.

[0012] According to one embodiment of this application, candidate angular frequencies and discrete parameters are combined and substituted into the propagation equation to obtain the interface matching matrix corresponding to the candidate angular frequencies and the normal wavenumber at the normal position within the density transition layer. This includes: substituting candidate angular frequencies and discrete parameters into the propagation equation at each discrete position within the density transition layer to obtain the normal wavenumber at the normal position within the density transition layer; selecting modes that decay towards infinity along the vacuum direction from the normal wavenumbers as vacuum-side modes, and selecting modes that decay towards infinity along the plasma center direction as plasma-side modes; selecting a matching region on the matching surface based on a preset asymptotic matching region width, splicing the vacuum-side modes and plasma-side modes within the matching region, and normalizing them according to the column 2 norm to obtain the interface matching matrix corresponding to the candidate angular frequencies. The matching surface is used to characterize the common spatial position where the vacuum-side modes and plasma-side modes are spliced ​​and the continuous conditions of the tangential electric field and tangential magnetic field are applied.

[0013] According to one embodiment of this application, the preset screening conditions further include: the difference between the second smallest singular value and the smallest singular value of the interface matching matrix is ​​greater than a third preset threshold; the normal discrete step length and the preset asymptotic matching region width are changed respectively to obtain a new bound operating point frequency, and the relative change between the new bound operating point frequency and the original bound operating point frequency is less than a preset convergence error; the attenuation constants obtained by exponential fitting of the electric field envelopes on both sides of the interface are all positive, and the outer boundary of the calculation region is moved outward to recalculate the electric field distribution to obtain the field peak position after the movement, and the field peak position after the movement is the same as the field peak position before the movement, wherein the interface is used to characterize the interface at the junction of vacuum and plasma in the vacuum-plasma device.

[0014] According to one embodiment of this application, the ion cyclotron interface coupling method further includes: acquiring the magnetic field margin, bulk isolation margin, density deviation, and composition deviation of the vacuum-plasma device, as well as the reflected power and port voltage of the antenna port of the radio frequency source; and reducing the radio frequency power of the radio frequency source or stopping the radio frequency output of the radio frequency source in response to at least one of the magnetic field margin, bulk isolation margin, density deviation, composition deviation, reflected power, and port voltage exceeding their respective preset safety thresholds.

[0015] This application determines multiple discrete parameter combinations, including a first ion ratio, background magnetic field, electron density profile, and tangential wavenumber components. For each discrete parameter combination, candidate angular frequencies are screened based on the interface matching matrix corresponding to the candidate angular frequency, the normal wavenumber at the normal position within the density transition layer, and the ion-ion hybridization margin. This yields the bound operating point frequency corresponding to the discrete parameter combination, and a relational table is constructed accordingly. During the operation of the vacuum-plasma device, the vacuum-plasma device and / or the radio frequency source are adjusted based on this relational table. This solves the problem that, due to the non-unique peak values ​​in the port loading spectrum corresponding to interface bound states, identification based solely on loading peaks or reflection phases can easily lead to misjudging bulk resonances or numerical pseudo-modes as interface states, making accurate ion cyclotron interface coupling impossible. This application achieves accurate identification of interface bound states and precise control of ion cyclotron interface coupling. Attached Figure Description

[0016] Figure 1 This is a flowchart of an ion cyclotron interface coupling method according to some embodiments of this application; Figure 2 This is a schematic diagram illustrating the construction of a matching matrix for interface constraint states according to some embodiments of this application; Figure 3 This is a schematic diagram of the structure of an ion cyclotron interface coupling system according to some embodiments of this application; Figure 4 This is a diagram showing the results of bulk dispersion exclusion and ion-ion hybridization exclusion along the density transition layer at a reference operating point according to some embodiments of this application; Figure 5 The normalized interface mode field strength distribution and two-sided exponential decay fitting diagrams are shown for the minority hydrogen ion ratios of 0%, 5%, and 20% according to some embodiments of this application. Figure 6 This is a spectrum of source-free bound operating point frequencies under different minority hydrogen ion ratios according to some embodiments of this application; Figure 7 This is a graph showing the bound and unbound working regions and critical magnetic field curves in the minority hydrogen ion ratio-background magnetic field plane according to some embodiments of this application; Figure 8 This is a logic diagram for monitoring and controlling magnetic field, frequency, volume wave attenuation, and ion-ion hybridization margin during operation according to some embodiments of this application. Detailed Implementation

[0017] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0018] The ion cyclotron interface coupling method of this application embodiment will now be described in detail with reference to the accompanying drawings.

[0019] In the following description, H (hydrogen)-D (deuterium) dual-ion magnetized plasma is used as an example, that is, the first ion is a hydrogen ion, but this is not intended to limit the scope of this application.

[0020] The vacuum-plasma device is used to provide and confine HD dual-ion magnetized plasma. The radio frequency source is used to generate radio frequency signals. The radio frequency antenna is set on the vacuum side of the vacuum-plasma device and spaced at a distance g from the vacuum-plasma interface. The radio frequency signal generated by the radio frequency source is fed into the radio frequency antenna through a transmission line and a matching network. The radio frequency wave is excited by the vacuum side where the radio frequency antenna is located. The radio frequency wave passes through the vacuum region and couples to the magnetized plasma in the vacuum-plasma device.

[0021] The vacuum-plasma device also includes a gas supply assembly and a magnetic field assembly. The gas supply assembly is used to supply hydrogen and deuterium into the vacuum-plasma device to adjust the first ion ratio, and the magnetic field assembly is used to generate a background magnetic field and adjust the intensity of the background magnetic field.

[0022] Figure 1 This is a flowchart of an ion cyclotron interface coupling method according to some embodiments of this application. (Refer to...) Figure 1 The ion cyclotron interface coupling method in this application embodiment may include the following steps: S110, determine multiple discrete parameter combinations, wherein each discrete parameter combination includes the first ion ratio of the vacuum-plasma device, the background magnetic field and the electron density profile, and the tangential wavenumber component of the radio frequency wave emitted by the radio frequency source.

[0023] Specifically, electron density profile The equilibrium electron number density of a vacuum-plasma device in the sense of before or over a radio frequency pulse, is expressed in units of 1000 kJ / m². This is not an instantaneous density disturbance caused by RF (Radio Frequency), and can be diagnosed by interferometers, microwave reflectometers, Thomson scattering, etc., followed by smoothing and monotonicity checks. The first ion ratio (hydrogen ion ratio) is defined as... , The hydrogen ion number density is [value], and the deuterium ion number density is [value]. The background magnetic field is the confinement magnetic field provided by the vacuum-plasma device, with tangential wavenumber components. , The Fourier wavenumber components of the antenna excitation field in the tangential directions y and z of the interface are given in meters. -1 The z-axis is along the background magnetic field, therefore It is a parallel wavenumber. It is the azimuth / tangential wavenumber.

[0024] The ranges of the first ion ratio, background magnetic field, and electron density profile of the vacuum-plasma device, as well as the range of the tangential wavenumber component of the radio frequency wave emitted by the radio frequency source, are discretized to obtain multiple discrete parameter combinations. Each discrete parameter combination includes the first ion ratio, background magnetic field, electron density profile, and tangential wavenumber component.

[0025] S120, substitute the candidate angular frequency and discrete parameters into the propagation equation to obtain the interface matching matrix corresponding to the candidate angular frequency and the normal wavenumber at the normal position in the density transition layer.

[0026] S130, substitute the candidate angular frequency into the cold magnetized plasma dielectric tensor to obtain the transverse diagonal parameter at the normal position in the density transition layer corresponding to the candidate angular frequency, and calculate the ion-ion hybridization margin corresponding to the candidate angular frequency based on the transverse diagonal parameter.

[0027] Specifically, for each discrete parameter combination among multiple discrete parameter combinations, multiple candidate angular frequencies are set; the first ion ratio, background magnetic field, electron density profile, and tangential wavenumber component in the current discrete parameter combination, as well as each candidate angular frequency among the multiple candidate angular frequencies, are substituted into the propagation equation (which can be constructed by the multi-component Maxwell-fluid equation), and the propagation equation is solved at each discrete position in the density transition layer to obtain the normal wavenumber at that discrete position. The normal wavenumbers at all discrete positions constitute the normal wavenumber at the normal position in the density transition layer corresponding to the candidate angular frequency.

[0028] From the normal wavenumbers at the normal position within the density transition layer, modes that satisfy the outward at infinity attenuation condition are selected to obtain the vacuum-side mode and the plasma-side mode. The vacuum-side mode and the plasma-side mode are spliced ​​at the matching surface and normalized according to the column 2 norm to obtain the interface matching matrix corresponding to the candidate angular frequency.

[0029] Then, by substituting each candidate angular frequency into the cold magnetized plasma dielectric tensor, the transverse diagonal parameters at each normal position within the density transition layer corresponding to the candidate angular frequency are obtained. ,in, Indicates the candidate angular frequency. x Represents the interface normal coordinates; then, Enter the following formula to calculate the ion-ion hybridization margin of the candidate angular frequency within the density transition layer: ; ; in, Indicates the ion-ion mixing margin; c represents the speed of light in vacuum; This represents the tangential wavenumber.

[0030] Thus, the interface matching matrix, normal wavenumber at the normal position within the density transition layer, and ion-ion hybridization margin corresponding to each candidate angular frequency of each discrete parameter combination were obtained.

[0031] S140, candidate angular frequencies are screened based on interface matching matrix, normal wavenumber and ion-ion hybridization margin, and candidate angular frequencies that meet preset screening conditions are determined as the bound operating point frequencies corresponding to discrete parameter combinations.

[0032] Specifically, after obtaining the interface matching matrix, normal wavenumber, and ion-ion hybridization margin corresponding to each candidate angular frequency, it is determined whether the interface matching matrix, normal wavenumber, and ion-ion hybridization margin of the candidate angular frequency meet the preset screening conditions. Based on the judgment results, the candidate angular frequencies are screened to determine the bound operating point frequency corresponding to the discrete parameter combination. For example, if the interface matching matrix, normal wavenumber, and ion-ion hybridization margin corresponding to a certain candidate angular frequency all meet their respective preset screening conditions, then that candidate angular frequency is determined to be the bound operating point frequency corresponding to the discrete parameter combination. In this way, the bound operating point frequency corresponding to each discrete parameter combination is obtained.

[0033] S150, a relationship table is constructed based on the confinement operating point frequencies corresponding to the discrete parameter combinations. This table characterizes the correspondence between the confinement operating point frequencies and the first ion ratio, background magnetic field, electron density profile, and tangential wavenumber components. During operation of the vacuum-plasma device, the vacuum-plasma device and / or the radio frequency source are controlled based on this relationship table. It should be noted that in this embodiment, the radio frequency source includes both the radio frequency source itself and its radio frequency antenna.

[0034] Specifically, after obtaining the bound operating point frequency corresponding to each discrete parameter combination, the first ion ratio, background magnetic field, electron density profile, and tangential wavenumber component in each discrete parameter combination are used as indexes, and the bound operating point frequency corresponding to the discrete parameter combination is used as the query result. The correspondence between the index and the query result is established, thereby obtaining the relationship table.

[0035] Before the ICRF (Ion Cyclotron Range of Frequencies) begins heating, an operating point can be selected by searching a table of electron density profiles within the vacuum-plasma device. The operating point includes the confinement operating frequency corresponding to the first ion ratio, background magnetic field, and tangential wavenumber component. The gas supply and magnetic field components of the vacuum-plasma device are then adjusted based on the first ion ratio and background magnetic field, while the radio frequency source and radio frequency antenna are adjusted based on the tangential wavenumber component and the confinement operating frequency.

[0036] For example, hydrogen can be supplied based on a first ion ratio-driven gas supply component (e.g., a hydrogen supply actuator), a background magnetic field can be supplied based on a background magnetic field driven magnetic field component (e.g., a magnetic field actuator), and the radio frequency angular frequency of the radio frequency source and the antenna spectrum center of the radio frequency antenna can be adjusted to satisfy the following equation based on the tangential wavenumber component and the bound operating point frequency: ; in, Indicates the driving frequency of the radio frequency source; Indicates the bounding operating point frequency; Indicates the preset frequency threshold; Indicates the center of the antenna spectrum; This represents the tangential wavenumber component.

[0037] After ICRF heating, during the operation of the vacuum-plasma device, the appropriate confinement operating point frequency can be determined from the relational table based on the actual operating state of the vacuum-plasma device, and the radio frequency source can be adjusted accordingly. Furthermore, when the parameters within the vacuum-plasma device deviate from the threshold, the vacuum-plasma device is adjusted to ensure that the vacuum-plasma device, the radio frequency source, or both operate at the confinement operating point frequency corresponding to the relational table, thereby exciting ion cyclotron interface coupling.

[0038] This application determines multiple discrete parameter combinations, including a first ion ratio, background magnetic field, electron density profile, and tangential wavenumber components. For each discrete parameter combination, candidate angular frequencies are screened based on the interface matching matrix corresponding to the candidate angular frequency, the normal wavenumber at the normal position within the density transition layer, and the ion-ion hybridization margin. This yields the bound operating point frequency corresponding to the discrete parameter combination, and a relational table is constructed accordingly. During the operation of the vacuum-plasma device, the vacuum-plasma device and / or the radio frequency source are adjusted based on this relational table. This solves the problem that, due to the non-unique peak values ​​in the port loading spectrum corresponding to interface bound states, identification based solely on loading peaks or reflection phases can easily lead to misjudging bulk resonances or numerical pseudo-modes as interface states, making accurate ion cyclotron interface coupling impossible. This application achieves accurate identification of interface bound states and precise control of ion cyclotron interface coupling.

[0039] In some embodiments, controlling the vacuum-plasma device and / or radio frequency source based on a relational table includes: acquiring the actual first ion ratio, actual background magnetic field, and actual electron density profile of the vacuum-plasma device; retrieving the relational table based on the actual first ion ratio, actual background magnetic field, and actual electron density profile of the vacuum-plasma device to obtain the target confinement operating point frequency and the target tangential wavenumber component; adjusting the driving frequency of the radio frequency source based on the target confinement operating point frequency in response to the absolute value of the frequency difference between the actual driving frequency of the radio frequency source and the target confinement operating point frequency being greater than a preset frequency threshold; and adjusting the antenna spectrum center of the radio frequency source based on the target tangential wavenumber component in response to the absolute value of the tangential wavenumber component deviation between the tangential wavenumber component corresponding to the antenna spectrum center of the radio frequency source and the target tangential wavenumber component being greater than a preset deviation threshold. The preset frequency threshold and preset deviation threshold can be calibrated according to actual conditions, and no specific limitations are imposed here.

[0040] Specifically, during the operation of the vacuum-plasma device, the first ion ratio, background magnetic field, and electron density profile within the device can be periodically measured using a diagnostic system installed on the device, yielding the actual first ion ratio, actual background magnetic field, and actual electron density profile. Using these actual first ion ratio, actual background magnetic field, and actual electron density profile as indexes, a relational table is retrieved to obtain the target confinement operating point frequency and the target tangential wavenumber component.

[0041] Then, based on the target constrained operating point frequency and the target tangential wavenumber component, it is determined whether the operating point of the RF source has drifted, that is, whether the actual driving frequency of the RF source and the actual antenna spectrum center deviate from the target constrained operating point frequency and the target tangential wavenumber component. If a drift is determined to have occurred, the output frequency of the RF source and the antenna spectrum center are adjusted based on the target constrained operating point frequency and the target tangential wavenumber component.

[0042] For example, the actual driving frequency of the RF source is obtained by periodically measuring the driving frequency of the RF source through a frequency detection unit set at the output end of the RF source, and the absolute value of the frequency difference between the actual driving frequency and the target constrained operating point frequency is calculated. Then, the absolute value of the frequency difference is compared with a preset frequency threshold, and the driving frequency of the RF source is adjusted based on the comparison result. For example, if the absolute value of the frequency difference is greater than the preset frequency threshold, the driving frequency of the RF source is adjusted based on the target constrained operating point frequency; if the absolute value of the frequency difference is less than or equal to the preset frequency threshold, the driving frequency of the RF source does not need to be adjusted.

[0043] Simultaneously, by detecting the feed phase distribution of the RF antenna, a Fourier transform is performed on the current distribution of the RF antenna in the tangential wavenumber space to obtain the spectral distribution of the RF wave excited by the RF antenna in the tangential wavenumber space. The tangential wavenumber component corresponding to the main peak position is extracted from the spectral distribution and used as the tangential wavenumber component corresponding to the antenna spectrum center of the RF source. The tangential wavenumber component deviation between the tangential wavenumber component and the target tangential wavenumber component is calculated. For example, the component deviation in each tangential direction is calculated separately, and the square root of the sum of the squares of each component deviation is taken as the tangential wavenumber component deviation. Then, the absolute value of the tangential wavenumber component deviation is compared with a preset deviation threshold. Based on the comparison result, it is determined whether to adjust the antenna spectrum center of the RF source. For example, if the absolute value of the tangential wavenumber component deviation is greater than the preset deviation threshold, the antenna spectrum center of the RF source is adjusted based on the target tangential wavenumber component; if the absolute value of the tangential wavenumber component deviation is less than or equal to the preset deviation threshold, the antenna spectrum center of the RF source does not need to be adjusted.

[0044] In some embodiments, the ion cyclotron interface coupling method further includes: acquiring the magnetic field margin, bulk spectrum isolation margin, ion-ion hybridization margin, and minimum bulk wave attenuation constant of the vacuum-plasma device; in response to the magnetic field margin being greater than a preset magnetic field margin threshold, the bulk spectrum isolation margin being greater than a preset bulk spectrum isolation threshold, the minimum bulk wave attenuation constant being less than a preset attenuation constant threshold, or the ion-ion hybridization margin being less than a preset ion-ion hybridization margin threshold, reducing the RF power of the RF source, and reselecting the target confinement operating point frequency, target tangential wavenumber component, target background magnetic field, and target first ion ratio based on a relational table; adjusting the driving frequency of the RF source based on the target confinement operating point frequency, adjusting the antenna spectrum center of the RF source based on the target tangential wavenumber component, and adjusting the vacuum-plasma device based on the target background magnetic field and the target first ion ratio. It should be noted that the method for acquiring the ion-ion hybridization margin has been described in detail in the above embodiments and will not be repeated here.

[0045] Specifically, during the operation of the vacuum-plasma device, the magnetic field margin is periodically acquired, and the formula for calculating the magnetic field margin is as follows: ; in, Indicates magnetic field margin; This represents the actual background magnetic field; Indicates the critical magnetic field for operation; This represents the actual hydrogen ion ratio. The operating critical magnetic field can be determined by consulting a table that corresponds to multiple hydrogen ion ratios and their respective operating critical magnetic fields.

[0046] During the operation of the vacuum-plasma device, the actual first ion ratio, actual background magnetic field, and actual electron density profile of the vacuum-plasma device are periodically acquired. Based on the actual first ion ratio, actual background magnetic field, and actual electron density profile, the bulk dispersion relation is solved at each discrete location within the density transition layer to obtain the bulk propagation band or bandgap edge at that discrete location. The frequency distance from the actual driving frequency of the current radio frequency source to the nearest bulk bandgap edge is calculated, and the minimum frequency distance among all discrete locations is taken as the bulk spectral isolation margin during the operation of the vacuum-plasma device.

[0047] During the operation of the vacuum-plasma device, the actual first ion ratio, actual background magnetic field, and actual electron density profile of the vacuum-plasma device, as well as the actual driving frequency and actual tangential wavenumber component of the radio frequency source, are periodically acquired. The actual first ion ratio, actual background magnetic field, actual electron density profile, actual driving frequency, and actual tangential wavenumber component are substituted into the propagation equation constructed by the multi-component Maxwell-fluid equation. The propagation equation is solved at each discrete location within the density transition layer to obtain the normal wavenumber at each discrete location. The absolute value of the imaginary part of the normal wavenumber at each discrete location is taken as the volume wave attenuation constant at that discrete location. The minimum value among all discrete locations within the density transition layer is taken as the minimum volume wave attenuation constant during the operation of the vacuum-plasma device.

[0048] After obtaining the magnetic field margin, bulk isolation margin, ion-ion hybridization margin, and minimum bulk wave attenuation constant of the vacuum-plasma device for the current cycle, these margins are compared with their respective thresholds. If any one or more of these margins do not meet their respective thresholds—for example, if the magnetic field margin is greater than a preset magnetic field margin threshold, the bulk isolation margin is greater than a preset bulk isolation margin threshold, the minimum bulk wave attenuation constant is less than a preset attenuation constant threshold, or the ion-ion hybridization margin is less than a preset ion-ion hybridization margin threshold—it means that the safety margin of the current operating point relative to the bulk propagation continuous spectrum, the ion-ion hybridization layer, or the magnetic field safety boundary is insufficient. This indicates that there is a risk that the current operating point will fall into the bulk propagation continuous spectrum or the ion-ion hybridization layer. In this case, the RF power of the RF source is reduced to reduce plasma disturbance, which can also prevent further deterioration of the operating point and save energy to some extent.

[0049] Conversely, if the magnetic field margin, bulk spectrum isolation margin, ion-ion hybridization margin, and minimum bulk wave attenuation constant all meet their respective thresholds, the RF power of the RF source can be increased to improve the ion cyclotron heating power and heating efficiency while maintaining the stability of the interface bound state and meeting the requirements of each safety margin.

[0050] After reducing the RF power of the RF source, the relationship table is re-searched based on the updated actual first ion ratio, actual background magnetic field, and actual electron density profile. The operating point is reselected, namely, the target confinement operating point frequency, the target tangential wavenumber component, the target background magnetic field, and the target first ion ratio are selected. The driving frequency of the RF source is adjusted based on the target confinement operating point frequency, and the antenna spectrum center of the RF source is adjusted based on the target tangential wavenumber component. The vacuum-plasma device is adjusted based on the target background magnetic field and the target first ion ratio.

[0051] After adjusting the vacuum-plasma device and radio frequency source based on the operating point, the magnetic field margin, bulk spectrum isolation margin, ion-ion hybridization margin, and minimum bulk wave attenuation constant of the vacuum-plasma device are re-acquired. If one or more of these still do not meet their respective thresholds, the radio frequency output of the radio frequency source is stopped.

[0052] In some embodiments, after constructing a relation table based on the bound operating point frequencies corresponding to the discrete parameter combinations, the method further includes: obtaining a first ion ratio in the discrete parameter combinations and determining the operating critical magnetic field corresponding to the first ion ratio; and deleting the discrete parameter combination from the relation table in response to the fact that the background magnetic field in the discrete parameter combinations is less than the sum of the operating critical magnetic field and the preset magnetic field margin.

[0053] In some embodiments, determining the operating critical magnetic field corresponding to the first ion ratio includes: acquiring a plurality of background magnetic fields corresponding to the first ion ratio, and filtering out the background magnetic fields with bound operating point frequencies from the plurality of background magnetic fields; and determining the minimum background magnetic field among the background magnetic fields with bound operating point frequencies as the operating critical magnetic field corresponding to the first ion ratio.

[0054] Specifically, the operating critical magnetic field is the minimum background magnetic field required to maintain the existence of the bound operating point. Below this value, the bound state will disappear or fall into the volume propagation continuum. The preset magnetic field margin is used to cover the uncertainties of the background magnetic field, density, composition, and model. Therefore, after constructing a relational table based on the bound operating point frequencies corresponding to discrete parameter combinations, the table needs to be further filtered to remove discrete parameter combinations with insufficient background magnetic fields. This ensures that the operating points retained in the table have sufficient magnetic field margin during operation, which can, to some extent, avoid operating point failure due to magnetic field fluctuations or measurement errors, thereby improving the stability and reliability of ion cyclotron interface coupling.

[0055] For example, firstly, the first ion ratio contained in each discrete parameter combination in the relation table is obtained, and the corresponding operating critical magnetic field is determined for this first ion ratio. The operating critical magnetic field refers to the lowest background magnetic field that can maintain the existence of the bound operating point under the condition of the first ion ratio. When the background magnetic field is lower than this value, the bound state will disappear or fall into the volume propagation continuum. The operating critical magnetic field can be determined as follows: obtain multiple background magnetic fields corresponding to the first ion ratio. For each background magnetic field, determine whether there is a bound operating point frequency under the conditions of the background magnetic field and the first ion ratio. After traversing all background magnetic fields corresponding to the first ion ratio, determine the minimum value among all background magnetic fields with bound operating point frequencies as the operating critical magnetic field corresponding to the first ion ratio. Subsequently, determine whether the background magnetic field corresponding to the first ion ratio is less than the sum of the operating critical magnetic field and the preset magnetic field margin. The preset magnetic field margin is used to cover the uncertainty of the background magnetic field, density, composition and model, and can be calibrated according to the actual situation without specific restrictions. If it is less than, it means that the discrete parameter combination may lose the bound operating point during operation due to magnetic field fluctuations or measurement errors. Therefore, the discrete parameter combination is deleted from the relation table. Through the above screening, the operating points retained in the relationship table all have sufficient magnetic field margin, which can, to a certain extent, avoid operating point failure due to magnetic field fluctuations or measurement errors, and improve the stability and reliability of ion cyclotron interface coupling.

[0056] In some embodiments, the preset screening conditions include: the minimum singular value of the interface matching matrix is ​​less than or equal to a first preset threshold; the number of volume propagation channels of the real normal wavenumber at the normal position within the density transition layer is zero; and the ion-ion mixing margin of the density transition layer is greater than or equal to a second preset threshold. The first and second preset thresholds can be calibrated according to actual conditions, and no specific limitations are imposed here.

[0057] Specifically, when screening candidate angular frequencies based on the interface matching matrix, normal wavenumber, and ion-ion hybridization margin, each candidate angular frequency is checked to see if it meets the preset screening conditions: First, check if the minimum singular value of the interface matching matrix corresponding to the candidate angular frequency is less than or equal to the first preset threshold. If it does, it indicates that the vacuum-side mode and the plasma-side mode are well spliced ​​at the matching surface, and the field decays exponentially on both sides of the interface. The minimum singular value of the interface matching matrix can be calculated based on the inverse power method. Second, check if the number of volume propagation channels of the real normal wavenumber at the normal position in the density transition layer is zero. If it is zero, it indicates that there are no real wavenumber channels propagating into the plasma, and energy will not leak to the plasma center. Finally, check if the ion-ion hybridization margin corresponding to the candidate angular frequency is greater than or equal to the second preset threshold. If it does, it indicates that the candidate angular frequency is far enough away from the ion-ion hybridization layer, which can, to some extent, avoid misjudging the false signals generated by the ion-ion hybridization layer as interface-bound states. When all three conditions are met, the candidate angular frequency is determined as the bound operating point frequency corresponding to the discrete parameter combination; when one or more of the three conditions are not met, the candidate angular frequency is not determined as the bound operating point frequency corresponding to the discrete parameter combination.

[0058] In some embodiments, the process of constructing the propagation equation includes: dividing the computational region into multiple discrete locations along the normal of the vacuum-plasma device by a normal discrete step size, wherein the computational region includes a density transition layer, which is used to characterize the region where the electron density gradually increases from the boundary of the vacuum-plasma device to the plasma center; and substituting the plasma parameters at each discrete location into the multi-component Maxwell-fluid equation to obtain the propagation equation at the corresponding discrete location.

[0059] Specifically, the multi-component Maxwell-fluid equations describe the interactions between electromagnetic waves and various components in a plasma, such as electrons, hydrogen ions, and deuterium ions. Solving these equations directly on the entire device is extremely complex; therefore, discretization along the normal direction of the vacuum-plasma device is necessary. For example, a normal discretization step size is first defined, and then the computational domain is divided into multiple discrete locations along the normal direction. This computational domain includes a density transition layer, which characterizes the region where the electron density gradually increases from the boundary of the vacuum-plasma device to the plasma center. In other words, the electron density does not increase abruptly from the boundary towards the plasma center; this region is the density transition layer.

[0060] After dividing the discrete locations, at each discrete location, the local plasma parameters are obtained, such as electron density, hydrogen ion ratio, deuterium ion ratio, and background magnetic field. Substituting these local parameters into the multi-component Maxwell-fluid equation, the propagation equation at that discrete location is obtained. The propagation equation describes how the wave propagates along the normal direction at that discrete location, and can usually be written as a dispersion relation with respect to the normal wave number.

[0061] In some embodiments, the candidate angular frequency and discrete parameter combination are substituted into the propagation equation to obtain the interface matching matrix corresponding to the candidate angular frequency and the normal wavenumber at the normal position within the density transition layer. This includes: substituting the candidate angular frequency, discrete parameter combination, and electron density profile into the propagation equation at each discrete position within the density transition layer to obtain the normal wavenumber at the normal position within the density transition layer; selecting modes that decay towards infinity along the vacuum direction from the normal wavenumber as vacuum-side modes, and selecting modes that decay towards infinity along the plasma center direction as plasma-side modes; selecting a matching region on the matching surface based on a preset asymptotic matching region width, splicing the vacuum-side mode and the plasma-side mode within the matching region, and normalizing according to the column 2 norm to obtain the interface matching matrix corresponding to the candidate angular frequency. The matching surface is used to characterize the common spatial position where the vacuum-side mode and the plasma-side mode are spliced ​​and the continuous conditions of the tangential electric field and tangential magnetic field are applied.

[0062] Specifically, the discrete parameter combinations and their corresponding candidate angular frequencies are substituted into the propagation equation at each discrete location within the density transition layer. For each discrete location substituted, the propagation equation is solved once to obtain the normal wavenumber at that location. The normal wavenumber refers to the spatial frequency of the wave propagating along the normal direction. The spatial frequency can be real, imaginary, or complex. If the normal wavenumber is real, it means the wave can propagate along the normal direction; if the normal wavenumber is imaginary or complex, it means the wave attenuates along the normal direction. Combining the normal wavenumbers obtained at all discrete locations constitutes the normal wavenumber at the normal location within the density transition layer.

[0063] After determining the normal wavenumber, not all modes can be used to construct interface-bound states. Interface-bound states require energy localization near the vacuum-plasma interface, preventing outward radiation into the vacuum region and leakage towards the plasma center. Therefore, it is necessary to select modes from the normal wavenumbers at normal positions within the density transition layer that satisfy the outward attenuation condition. Specifically, there are two categories: one is modes that attenuate towards infinity along the vacuum direction, called vacuum-side modes; the other is modes that attenuate towards infinity along the plasma center direction, called plasma-side modes. In the vacuum-side mode, the field strength gradually decreases as it moves away from the interface in the vacuum region; in the plasma-side mode, the field strength gradually decreases as it moves towards the center in the plasma region. Only such modes can be pieced together to form a bound state localized near the interface.

[0064] The common spatial location where the vacuum-side and plasma-side modes are spliced ​​together and the continuity conditions of the tangential electric and magnetic fields are applied is defined as the matching surface. Near the matching surface, a matching region needs to be selected according to the preset asymptotic matching region width. This matching region is not a single point, but a segment near the matching surface. This is done to avoid numerical errors caused by single-point matching and to make the splicing result more stable. Within this matching region, the vacuum-side and plasma-side modes are spliced ​​together. The physical requirement for splicing is the continuity of the tangential components of the electromagnetic field; that is, the tangential electric and magnetic fields must transition continuously within the matching region without abrupt changes. All possible mode combinations and continuity conditions are written as a system of linear equations, and then normalized according to the column 2 norm to obtain the interface matching matrix corresponding to the candidate angular frequencies. A schematic diagram of the construction of the matching matrix for the interface bound states is shown below. Figure 2 As shown.

[0065] Each column of the interface matching matrix corresponds to a mode on the vacuum side, and each row corresponds to a mode on the plasma side. The elements in the matrix reflect the degree of matching when the modes on both sides are spliced ​​together in the matching region. By checking conditions such as the minimum singular value of this matrix, it can be determined whether a true interface-bound state exists at the candidate angular frequency.

[0066] In some embodiments, the preset screening conditions further include: the difference between the second smallest singular value and the smallest singular value of the interface matching matrix is ​​greater than a third preset threshold; the normal discrete step size and the preset asymptotic matching region width are changed respectively to obtain a new bound operating point frequency, and the relative change between the new bound operating point frequency and the original bound operating point frequency is less than a preset convergence error; the attenuation constants obtained by exponential fitting of the electric field envelopes on both sides of the interface are all positive, and the outer boundary of the calculation region is moved outward to recalculate the electric field distribution to obtain the field peak position after the movement, which is the same as the field peak position before the movement. The interface is used to characterize the boundary between vacuum and plasma in the vacuum-plasma device. The third preset threshold and the preset convergence error can be calibrated according to actual conditions, and no specific restrictions are imposed here.

[0067] Specifically, while relying solely on the minimum singular value of the interface matching matrix, the number of volume propagation channels, and the ion-ion hybridization margin can screen out candidate angular frequencies that formally meet the interface bound state requirements, various artifacts may still exist in numerical calculations. For example, multiple pairs of modes may simultaneously approach matching, resulting in a small minimum singular value that is not dominated by a single physical mode; the calculation results may also heavily depend on the selection of the normal discrete step size and the width of the asymptotic matching region, constituting a numerical pseudo-mode; furthermore, the field peak position may drift with the movement of the outer boundary of the computational domain, indicating that the mode is not truly localized near the interface but is affected by the truncation of the computational domain. Therefore, further supplementary screening conditions are needed to ensure that the finally determined bound operating point frequencies are physically real, numerically convergent, and independent of the computational parameters.

[0068] The process of further validating the candidate angular frequencies by adding additional screening criteria is as follows: Singular value decomposition of the interface matching matrix yields the minimum and second-minimum singular values. The minimum singular value corresponds to the best-matched pair of vacuum-side and plasma-side modes, while the second-minimum singular value corresponds to the second-best-matched pair of modes. The difference between the second-minimum and minimum singular values ​​is calculated. If this difference is greater than a third preset threshold, it indicates that the minimum singular value is significantly smaller than the second-minimum singular value, meaning only one pair of modes has achieved a good match and dominates, while the matching degree of other modes is far inferior. Therefore, false bound states caused by multiple pairs of modes simultaneously approaching a match can be ruled out, confirming that the bound state corresponding to the candidate angular frequency is unique and reliable. If the difference is less than or equal to the third preset threshold, it indicates that the second-minimum and minimum singular values ​​are not significantly different, suggesting multiple pairs of modes are simultaneously approaching a match. In this case, it is impossible to determine which pair of modes is the true physical bound state. Other nearly-matched modes may be false matches caused by volume resonance, antenna resonance, or numerical pseudo-modes. If the mode corresponding to the minimum singular value is still considered a bound state, misjudgment is likely, and therefore the candidate angular frequency cannot pass the screening.

[0069] By changing the normal discretization step size and the preset asymptotic matching region width, the aforementioned substitution, solution, filtering, and splicing steps are repeated to obtain new bound operating point frequencies. If the relative change of the new bound operating point frequency relative to the original bound operating point frequency is less than the preset convergence error, it indicates that the bound operating point frequency does not depend on the discretization parameters and the matching region width, and has numerical convergence, thus eliminating numerical pseudo-modes caused by improper mesh generation or matching region selection. If the relative change of the new bound operating point frequency relative to the original bound operating point frequency is greater than or equal to the preset convergence error, it indicates that the bound operating point frequency is highly dependent on the normal discretization step size and the asymptotic matching region width. Changing the mesh set or the matching region width will significantly change the calculated frequency. Such results are essentially pseudo-modes generated during the numerical discretization process, rather than physically existing bound states. Therefore, this candidate angular frequency cannot pass the filtering.

[0070] An exponential fit is performed on the electric field envelopes on both sides of the interface. If the resulting decay constants are all positive, it indicates that the electric field decays exponentially with distance from the interface on both sides, and the energy is indeed localized near the interface, consistent with the characteristics of an interface-bound state. If the decay constant is zero or negative, it indicates that the electric field does not decay or even increases on one side, and the energy will radiate outward or leak towards the plasma center. This mode is not a true interface-bound state. Simultaneously, the outer boundary of the computational region is moved outward and the electric field distribution is recalculated. If the peak position after the move is the same as the peak position before the move, it indicates that the peak position is determined by the physical localization at the interface and does not change with the movement of the outer boundary of the computational region, further proving that this mode is a true interface-bound state. If the peak position after the move is different from the peak position before the move, it indicates that the peak position depends on the outer boundary of the computational region and may be an artifact caused by boundary reflection or truncation of the computational region, rather than a true bound state. Therefore, this candidate angular frequency cannot pass the screening.

[0071] When all three conditions are met, the candidate angular frequency can pass the screening and be determined as the bound operating point frequency corresponding to the discrete parameter combination; when one or more of the three conditions are not met, the candidate angular frequency will not be determined as the bound operating point frequency corresponding to the discrete parameter combination.

[0072] Thus, by using the above-mentioned supplementary screening conditions, the reliability of identifying the frequency of the bound working point can be significantly improved, providing an accurate basis for subsequent construction of the relationship table and control during operation.

[0073] In some embodiments, the ion cyclotron interface coupling method further includes: acquiring the magnetic field margin, bulk isolation margin, density deviation, and composition deviation of the vacuum-plasma device, as well as the reflected power and port voltage of the antenna port of the radio frequency source; and reducing the radio frequency power of the radio frequency source or stopping the radio frequency output of the radio frequency source in response to at least one of the magnetic field margin, bulk isolation margin, density deviation, composition deviation, reflected power, and port voltage exceeding their respective preset safety thresholds. It should be noted that the methods for acquiring the magnetic field margin and bulk isolation margin of the vacuum-plasma device have been described in detail in the above embodiments and will not be repeated here.

[0074] Specifically, density deviation refers to the deviation of the measured electron density profile relative to a reference electron density profile during the operation of a vacuum-plasma device. Specifically, it can be obtained by measuring the actual electron density profile in real time using at least one of a laser interferometer, microwave reflectometer, or Thomson scattering diagnostic system, and obtaining the reference electron density profile corresponding to the current operating condition from calibration reference data or a relational table. Multiple sampling locations are selected along the interface normal within the density transition layer. At each sampling location, the difference between the actual and reference electron density profiles is calculated and divided by the reference electron density profile to obtain the relative density deviation at that sampling location. The relative density deviations at multiple sampling locations are summarized into a single value, which is one of the following: the maximum absolute value of the relative density deviations across all sampling locations, the root mean square value of the relative density deviations across all sampling locations, or the interface position offset between the actual and reference electron density profiles. This value is taken as the density deviation.

[0075] Component deviation refers to the absolute or relative deviation between the measured minority ion ratio and the set minority ion ratio, used to reflect changes in the hydrogen-deuterium ratio caused by gas supply, pumping, and ionization equilibrium. Specifically, it is obtained by measuring the intensity ratio of hydrogen and deuterium spectral lines through spectral diagnostics, and combining this with a pre-calibrated correspondence between the spectral line intensity ratio and the minority ion ratio to obtain the actual minority ion ratio; obtaining the set minority ion ratio corresponding to the current operating condition from a relationship table or set value; and calculating the absolute or relative deviation between the actual and set minority ion ratios as the component deviation.

[0076] The reflected power at the antenna port of an RF source refers to the power returning from the antenna port along the feed line to the RF source. It reflects the degree of impedance mismatch between the antenna and the transmission line, and how much power is reflected back instead of entering the plasma. The reflected power is typically measured by a directional coupler located on the transmission line between the RF source and the matching network.

[0077] The port voltage at the antenna port of an RF source refers to the complex RF voltage or its peak / root mean square value at the antenna feed terminal. It reflects the level of voltage stress at the antenna port, limiting breakdown and insulation stress, and preventing arcing or insulation damage due to excessive voltage. The port voltage can be measured by installing a voltage probe or a calibrated voltage / current sensor at the antenna feed terminal.

[0078] When at least one of the following parameters—magnetic field margin, bulk isolation margin, density deviation, composition deviation, reflected power, and port voltage—exceeds its corresponding preset safety threshold, it indicates that the current operating point has deviated from the safe operating range. Continuing to maintain the original RF power may cause the operating point to fall into the bulk propagation continuum or ion-ion hybrid layer, resulting in interface bound state failure, decreased heating efficiency, or damage to the RF source, transmission line, or antenna due to excessive reflected power or port voltage, even leading to breakdown and insulation failure. Therefore, in this situation, reducing the RF power of the RF source or stopping the RF output of the RF source can promptly reduce plasma disturbance and electromagnetic stress, bringing the operating point back to the safe range, or creating conditions for reselecting the operating point.

[0079] In this way, equipment damage can be avoided to a certain extent and energy can be prevented from being injected after the confinement state fails. At the same time, adjustment space is provided for re-searching the relation table and re-selecting the target confinement operating point frequency, target tangential wavenumber component, target background magnetic field and target first ion ratio that meet all safety conditions. This improves the stability of ion cyclotron interface coupling and heating efficiency while protecting the equipment.

[0080] As a specific example, the invention is illustrated below using HD dual-ion magnetized plasma. The current verification and listed working region values ​​are limited to the HD cold, localized, one-dimensional model. Other ion combinations require re-verification of the matching zero point, bilateral attenuation, volume channels, hybrid layers, and critical magnetic field before establishing the corresponding working region.

[0081] Reference Figure 3 The ion cyclotron interface coupling system includes: a vacuum cavity 1, in which a vacuum region, a density transition layer 4 and a magnetized plasma region 2 containing deuterium ions and hydrogen ions are formed sequentially along the interface normal, and a vacuum-plasma interface 3 is formed between the vacuum region and the magnetized plasma region 2.

[0082] The gas supply assembly includes a deuterium supply unit 7, a hydrogen supply unit 8, and a mass flow controller 9. The deuterium supply unit 7 and the hydrogen supply unit 8 are respectively connected to the gas inlet of the vacuum chamber 1 via the mass flow controller 9 to change the first ion ratio. .

[0083] The magnetic field assembly includes a main magnet 5 disposed outside the vacuum cavity 1 and a magnetic field power supply 6 electrically connected to the main magnet 5. The setting interface of the magnetic field power supply 6 constitutes a magnetic field actuator to change the background magnetic field inside the vacuum cavity 1. The main magnet 5 is driven by the magnetic field power supply 6, generating a magnetic field along... z Background magnetic field in the direction .

[0084] The radio frequency (RF) coupling assembly includes an ion cyclotron band antenna 10 disposed within the vacuum region and facing interface 3, an RF source 11, an RF port 20, and an antenna spectrum actuator 12. The output of the RF source 11 is electrically connected to the ion cyclotron band antenna 10 via a feed line and the RF port 20. The frequency setting interface of the RF source 11 constitutes the frequency actuator. The antenna spectrum actuator 12 includes at least one of an array phase controller, a switchable feed point, or an adjustable current distributor, and is connected to the ion cyclotron band antenna 10 to change the antenna current spectrum center and polarization weight. ,in These represent the components of the antenna surface current in the two tangential directions. The ion cyclotron band antenna 10 is a phase-controllable array, with adjacent antenna elements along... y , z The spacing in each direction is respectively The phase increments are respectively The antenna spectrum actuator 12 sets the antenna spectrum center according to the following formula: ; in, These are the center wavenumbers of the antenna current spectrum in the two tangential directions, respectively.

[0085] The ion cyclotron band antenna 10 is positioned on the vacuum side and spaced apart from the interface by a distance. , .

[0086] The diagnostic and monitoring components include a density diagnostic unit 15 and a composition diagnostic unit 16 facing the magnetized plasma region 2, a magnetic field measurement unit 17 located near the vacuum cavity 1 or the main magnet 5, a safety monitoring unit 13 coupled to the radio frequency port 20 and acquiring forward and reflected power, and a port voltage measurement module 14 electrically connected to the radio frequency port 20. The density diagnostic unit 15 can obtain an electron density profile using an interferometer, reflectometer, or probe array. The component diagnostic unit 16 can obtain the first ion ratio using gas supply calibration, spectral diagnostics, or neutral particle analysis. The magnetic field measurement unit 17 obtains the background magnetic field. .

[0087] The data input terminals of the calculation unit 19 are connected to the density diagnostic unit 15, the component diagnostic unit 16, and the magnetic field measurement unit 17, respectively. These are used to establish a multi-component Maxwell-fluid interface matching matrix and a volume dispersion equation based on the diagnostic data, and to perform calculations according to the matching zeros, two-sided attenuation, and no real-time conditions. The combination criteria for (normal wavenumber) volume channels without ion-ion hybrid layers generate bound state frequency mapping and critical magnetic field mapping.

[0088] Control unit 18 is signal-connected to computing unit 19. Its control output terminal is connected to mass flow controller 9, magnetic field power supply 6, radio frequency source 11 and antenna spectrum actuator 12 respectively. It is used to send components, magnetic field, frequency and antenna spectrum control quantities according to the bound working area mapping and positive spectral isolation margin.

[0089] Safety interlock unit 21, the input terminal of which is connected to safety monitoring unit 13, port voltage measurement module 14 and control unit 18 respectively, and the output terminal is connected to the enable terminal or power adjustment terminal of radio frequency source 11, is used to reduce radio frequency power or stop radio frequency output when at least one of the magnetic field margin, the bulk spectrum isolation margin, the density deviation, the component deviation, the reflected power and the port voltage exceeds their respective preset safety thresholds.

[0090] Example 1: Physical Object and Parameter Acquisition The parameters used in this embodiment are as follows: ; ; ; ; ; ; in, This indicates the electron density at the center of the plasma; Indicates the normal direction along the interface within the device. x The equilibrium electron number density; x Represents the interface normal coordinates; w Indicates the feature width of the density transition layer; Indicates the background magnetic field; and This represents the tangential wavenumber component.

[0091] The ionic components satisfy: ; ; in, Represents the hydrogen ion number density; Indicates the proportion of hydrogen ions; Represents electron number density; This represents the deuterium ion number density.

[0092] Example 2: Dielectric Model and Source-Free Interface Matching For species ,definition: ; ; in, Indicates species s cyclotron frequency; e D represents electrons; D represents deuterium ions; H represents hydrogen ions; Indicates species s The charge; Indicates the background magnetic field; Indicates species s The quality; Indicates species s The plasma angular frequency; Represents the vacuum permittivity; Indicates the position in the normal direction x species at the place s The number density.

[0093] In collision-free source free computation, the dielectric tensor of cold magnetized plasma is written as follows: ; ; ; ; in, S , D , P Indicates the Stix dielectric parameters; i Represents the imaginary unit; This indicates the scanning angular frequency.

[0094] Take the tangential field state ,in, Represents the tangential electric field y Quantity; Represents the tangential electric field z Quantity; Indicates tangential magnetic field y Quantity; Indicates tangential magnetic field z Quantity.

[0095] The result is obtained by eliminating the normal field component from Maxwell's equations and the dielectric tensor. Normal propagation matrix.

[0096] right y , z , t After performing a Fourier transform, the equation can be written as: ; Find the results in the left and right asymptotic regions respectively. M The eigenspace is selected, and modes decaying towards infinity are chosen. To prevent numerical basis collapse during propagation, periodic QR orthogonalization can be performed. The left and right decaying subspaces are propagated to... The matching surface, according to the tangential direction Construct the interface matching matrix under continuous conditions: ; in, Represents the interface matching matrix; Represents the state vector on the vacuum side (left side); This represents the state vector on the plasma side (right side).

[0097] After constructing the matching matrix, divide each column by its L2 norm. Perform a coarse scan within the preset frequency band. (The minimum singular value of matrix A), then refine the candidate frequencies using real frequency minimization or zero-point algorithm. To establish the numerical zeros of the matching matrix, At that time, we obtained: ; ; ; in, Indicates the bounding operating point frequency; This represents the minimum singular value of the interface matching matrix; This represents the second smallest singular value of the interface matching matrix.

[0098] The results indicate that an isolated matching matrix rank deficiency occurs at this frequency, rather than a general ill-conditioning across the wide frequency band.

[0099] Example 3: Spatial Locality and Pseudo-Model Elimination The electromagnetic field is reconstructed by taking the null space vector corresponding to the smallest singular value of the matching matrix, and then subjected to exponential fitting using the normalized field envelope. The normalized electric field envelope is as follows: ; in, Indicates the normalized electric field envelope at position x The ratio of the electric field strength at a given point to its maximum value; Represents the tangential electric field y Components in position x The value at; Represents the tangential electric field z Components in position x The value at; The magnitude of the tangential electric field vector represents the total intensity of the tangential electric field at that location. This represents the maximum value of the total tangential electric field strength at all locations.

[0100] for The vacuum side and plasma side respectively satisfy: , ; , ; ; ; in, Indicates the attenuation length on the vacuum side; This indicates the plasma-side attenuation length.

[0101] Set the asymptotic matching half-width to 0.8m, 1.0m, and 1.2m respectively. The frequencies obtained were 28.5001665625MHz, 28.5001664636MHz, and 28.5001663102MHz, respectively; the maximum absolute deviation relative to the 1.0m result was... MHz, the total span of the three results is MHz. The field peak remains near the interface and does not move with the outer boundary. This eliminates standing wave pseudo-modes generated by the boundaries of the finite computational region.

[0102] Example: Exclusion of four-body propagation channels and IIH layer: At candidate frequency For each density sampling point within the density transition layer, the solution is obtained: ; Where det[·] represents the determinant of the matrix; The dextral vector representing the refractive index vector; n I represents the refractive index vector; I represents the identity matrix. Indicates at angular frequency and normal position x The cold magnetized plasma dielectric tensor at the location.

[0103] In the prior statement Within the search interval, statistical results are obtained by searching for polynomial roots, generalized eigenvalues, or the minimum singular value of the determinant. The quantity. Under reference operating conditions, from the vacuum end to... Throughout the entire density gradient, The number of channels is zero, among which, Indicates the normal wave number.

[0104] ; ; in, Indicates the ion-ion hybridization function; Indicates the frequency of the bound operating point and normal position x The transverse diagonal parameter of the dielectric tensor of the cold magnetized plasma at the location; Indicates parallel refractive index; This represents the tangential wavenumber component, i.e., the wavefront component. z Wave number in direction; c It represents the speed of light in a vacuum.

[0105] Throughout the density slope Since it does not pass through a zero point, there is no local IIH conversion layer at the reference frequency. The reference operating points were determined using 401, 1601, and 6401 density sampling points and 10... -6 10 -7 10 -8 When there are three relative tolerances for real roots, the maximum real root is... All channels are zero; minimum It is 0.826565m -1 ,and .

[0106] Composed of matched zeros, two-sided attenuation, and no real The four results for the channel and the absence of the IIH layer allow us to determine the mode as a spectrally isolated interface-bound state within the applicable range of the cold, localized model in this embodiment. When the plasma temperature is high and the finite Larmor radius effect is not negligible, the dielectric tensor can be replaced with a thermal plasma or kinetic dielectric operator, and the absence of the real layer can be considered as a spectrally isolated interface-bound state. The screening is extended to the shortwave branches included in the model used; this replacement does not change the working area screening and margin control process of this application.

[0107] The results of bulk dispersion exclusion and ion-ion mixing exclusion along the density transition layer below the reference operating point are shown in the figure below. Figure 4 As shown.

[0108] Example 5: Minority Ion Ratio Frequency Modulation exist With all other reference parameters unchanged, the hydrogen ion ratios were set sequentially to 0%, 1%, 3%, 5%, 10%, and 20%. The zero points of the previous set of data were continuously extended to obtain Table 1.

[0109] Table 1: Bound state parameters under different hydrogen ratios

[0110] The overlap of the inner product modes of adjacent component points is greater than 0.998, indicating that the tracked data is from the same continuous branch rather than a jump between different zeros. The controller can store Table 1 as a lookup table or recalculate it online after each density and magnetic field update. If the target frequency is between adjacent data points, the continuation calculation result is used, and the interpolation result is only used as the initial value for zero search.

[0111] A minority of hydrogen ions change through their cyclotron poles S , D , P Then, the projection volume spectrum boundary and interface matching conditions are moved. Because Since this branch already exists, this application uses a minority of hydrogen ions to regulate the interface state, rather than describing it as the creation of the interface state by hydrogen.

[0112] The normalized interfacial mode field strength distribution and the fitted graph of two-sided exponential decay when the proportion of minority hydrogen ions is 0%, 5%, and 20% are shown in the figure. Figure 5 As shown in the figure. The source-free bound operating point frequency diagrams for different proportions of minority hydrogen ions are as follows. Figure 6 As shown.

[0113] Example 6: Magnetic Field-Driven Binding-Unbinding Control In each Change The interface is continuously tracked to match the zero point, and the volume dispersion is re-counted at the zero point. Number of channels. If the zero point is real If the number of channels is non-zero, then this parameter point will not be included in the bound work area; if the actual number of channels is non-zero, then the parameter point will not be included in the bound work area. If the number of channels is zero and the conditions of Embodiments 3 and 4 are met, then the parameter point is written into the available work area.

[0114] The critical magnetic field under the reference parameters is shown in Table 2. The listed values ​​represent the first time the magnetic field satisfies zero real magnetic field when scanned in 0.01T increments. The operational grid points of the channel conditions do not represent continuous critical points with infinite precision.

[0115] Table 2: Critical magnetic field for different hydrogen ratios

[0116] For example, choose and At that time, relative to A magnetic field margin of approximately 0.19T is provided. The actual margin should be determined based on magnetic field ripple, density measurement error, composition error, and finite temperature correction, and is not limited to the values ​​mentioned above.

[0117] The controller can also select parameters in reverse order based on the experimental objective: when the maximum usable field strength of the magnet is limited, it first selects parameters from... The diagram selects options that provide sufficient margin. , and then from The target radio frequency is obtained from the data; when the radio frequency source bandwidth is limited, a feasible frequency is first determined from the target frequency. combination.

[0118] The graphs of the minority hydrogen ion ratio, the bound and unbound working regions in the background magnetic field plane, and the critical magnetic field are shown below. Figure 7 As shown.

[0119] Example 7: Antenna Wavenumber Spectrum and Margin Control The antenna current is taken as a finite-width Gaussian current plate: ; in, Represents the antenna surface current density vector, and represents the current density vector in the tangential coordinate system. Current distribution at; Indicates the amplitude of the port current; This represents the normalization coefficient determined according to the port current definition used. express Normalized polarization weights, These are the components of the antenna surface current in the two tangential directions, respectively; Indicates the width of the current distribution in two tangential directions; This indicates the center of the antenna spectrum. In the embodiments of this application, the values ​​of each parameter are as follows: ; ; ; ; ; For practical strip antennas, loop antennas, or phase arrays, the Gaussian spectrum described above can be replaced with the wavenumber spectrum obtained from actual measurements or electromagnetic simulations. For phase-controllable arrays, adjacent elements along... y , z The spacing in the direction is The phase increment is The controller sets the antenna spectrum center using the following formula: ; in, These are the center wavenumbers of the antenna current spectrum in the two tangential directions, respectively.

[0120] According to the goal Set the radio frequency; the controller calculates during operation. and , and The calculation formula is as follows: ; ; in, Indicates magnetic field margin; This represents the actual background magnetic field; Indicates the critical magnetic field for operation; Indicates frequency deviation; Indicates the frequency of the radio frequency source; This indicates the angular frequency of the bound operating point.

[0121] And obtain the minimum attenuation constant from the density-wise volume dispersion root. Obtained from dielectric tensor Only when , , and Simultaneously, RF power is only allowed to be increased when it is within the preset allowable range. Reflected power and port voltage are only used as safety monitoring parameters; power is reduced when safety monitoring parameters exceed limits, but candidate branch classification or state-selective impedance matching is not performed based on the complex S-parameters across multiple disturbance points. The monitoring and control logic diagram for magnetic field, frequency, bulk wave attenuation, and ion-ion hybridization margin during operation is shown below. Figure 8 As shown.

[0122] The cold, non-destructive calculations in this embodiment only determine the interface coupling operating point and spectral isolation margin, and do not equate the port unreflected power with the electronic or ion heating power. If it is necessary to determine the species-resolved heating power, collision or kinetic dissipation models, local power density diagnostics, and closed Poynting power balances should also be added.

[0123] Example 8: Control Program and Data Structure The computing unit can store each working point as a data record: ; in, Indicates the solid density slope across the entire area. The maximum number of channels.

[0124] Only when , , , , , Furthermore, records are only added to the available working point database after passing grid and region convergence tests. Threshold , and Pre-calibrated according to calculation accuracy, measurement uncertainty, and the dielectric model used.

[0125] In this numerical embodiment, the matching matrix is ​​first normalized according to the column 2 norm; the coarse screening threshold is taken as... Refine and confirm the threshold. and take .Reality Root adopted .

[0126] Determination: Density gradient should be verified using at least 401 sampling points, and repeated at 1601 and 6401 points. Example of ion-ion hybridization safety threshold. These values ​​are the algorithm parameters for this embodiment and do not limit the selection of other convergence-verified thresholds.

[0127] After the system starts up, the control unit executes the following commands in sequence: Step 1: Read the latest density, composition, and magnetic field; Step 2: Query the available workpoint database or update online. ; Step 3: Calculate the target settings including magnetic field margin and frequency margin; Step 4: After limiting, send the set value to the mass flow controller, magnetic field power supply and radio frequency source; Step 5: Confirm at low power that the RF frequency, antenna spectrum center, and isolation margin of each spectrum are within the allowable range; Step 6: After satisfying the reflected power, port voltage, and various margin interlocking conditions, gradually increase the RF power; Step 7: Periodically read density, composition, magnetic field, reflected power, and port voltage during the pulse period. Perform fast feedback for RF frequency and array phase, and slow feedback for gas composition and magnetic field; reflected power is only used for safety limiting.

[0128] The above program can be implemented by one or more of the following: industrial controller, real-time computer, field-programmable gate array, and host computer software.

[0129] Example 9: Calibration and Hierarchical Control from Numerical Working Area to Device Setpoints: This embodiment provides a set of engineering parameters for a magnetic mirror ICRF device, enabling those skilled in the art to convert the numerical operating ranges obtained in Embodiments 2 to 8 into diagnostic, actuator, and interlocking settings. The following values ​​are an implementable example and should be recalibrated based on the rated voltage, magnetic field response, and diagnostic accuracy of the specific device.

[0130] In the low-power calibration phase, a 5MHz-40MHz vector network analyzer or in-phase quadrature receiver is used to establish a unified reference plane at the antenna feed point. First, open-circuit, short-circuit, 50Ω loads and through-pass devices are connected to complete SOLT (Short-Open-Load-Through), TRL (Through-Reflect-Line), or equivalent calibration. Then, the two-port transmission matrix of the feed line, directional coupler, and fixed matching network is measured. The measured total transmission matrix is ​​left-multiplied by the inverse of the fixture transmission matrix to obtain the antenna reference plane load. The 50Ω verification load is used for retesting. If the residual reflection amplitude is greater than 0.02 or the phase repeatability is worse than 2°, the high-power step is not initiated, and recalibration is performed.

[0131] Diagnostic data uses uncertainty intervals rather than single-point inputs. An example acceptance configuration is: relative error of electron density no greater than 5%, absolute error of hydrogen ratio no greater than 0.5 percentage points, background magnetic field error no greater than 2 mT, complex reflection amplitude error no greater than 0.01, and phase error no greater than 1°. The controller repeats bound-state discrimination at the endpoints and nominal values ​​of the measurement interval; only when all samples meet the requirements... =0、 d IIH >0.02、 > and B 0- Bc Only when the power exceeds 0.05T is the point marked as a usable operating point robust to measurement errors. If only the nominal point passes, it is reserved as a low-power verification point and direct increase to rated power is not permitted.

[0132] A layered control cycle is adopted: the sampling period for directional coupler, port voltage, and overcurrent interlock is 1μs-10μs; the fast feedback period for RF frequency and array phase is 0.1ms-1ms; the update period for density profile and state mapping is 1ms-10ms; and the hydrogen-deuterium flow rate and main magnetic field settings are updated with slow feedback or discharge-by-discharge for 20ms-100ms. The slow actuator does not participate in microsecond-level overvoltage protection, and the RF source first reduces power or shuts down when any fast interlock is triggered.

[0133] Taking a 1MW forward power and a 50Ω feeder as an example, the effective value of the forward traveling wave voltage is approximately 7.07kV. A reflected power warning threshold of 0.2 and a power reduction threshold of 0.35 are set. An alert is issued when the voltage measured by the feeder or matching component reaches 80% of its rated value, and a rapid power reduction is initiated when it reaches 90%. These thresholds are the initial settings for this embodiment; in actual use, pulse length, connector ratings, vacuum window field strength, and internal voltage amplification of the matching component should also be taken into account.

[0134] In this embodiment of the application, the definition and acquisition method of each parameter are shown in Table 3: Table 3: Symbols and their corresponding physical meanings in this application

[0135] This embodiment completes the conversion of "diagnostic uncertainty - model margin - actuator bandwidth - hardware interlocking". Before implementation, the transmission delay and protection action time should be verified by low-power frequency sweep, virtual load or hardware-in-the-loop test; before obtaining data of this type of device, the above example thresholds are not presented as safety limits applicable to all ICRF devices.

[0136] In summary, this invention establishes a four-layer control scheme of "offline work area generation - spectrum isolation confirmation - actuator coordinated adjustment - safety monitoring".

[0137] The first layer is the source free workspace generation layer. (Based on actual measurements or settings.) , , , and To establish cold, localized, multi-component Maxwell-fluid equations. On the vacuum side, the direction of... The decaying modes, selectively directed on the plasma side The attenuated modes propagate two sets of modes to the same matching surface, and a matching matrix is ​​constructed based on the tangential electromagnetic field continuity condition. A Searching on the real frequency axis The isolated zero point.

[0138] The second layer is the source-free working region screening layer. For each model zero, the normal field distribution is reconstructed, and the following checks are performed: the smallest singular value of the matching matrix is ​​close to zero and separate from the second smallest singular value; the field decays exponentially on both the vacuum and plasma sides; and... The volume dispersion equation does not exist across the entire density gradient. Solution: Throughout the entire density gradient, If the value is not zero, the local ion-ion hybrid conversion layer is excluded; after changing the normal grid and matching region, the candidate frequency and field peak position converge. Only model zeros that pass the above combined criteria are written into the source-free working area database and denoted as... This step is used to generate the controllable feasible region, without performing candidate branch identification or state classification based on the measured complex S-parameters.

[0139] The third layer consists of the feasible region and the control layer. and By extending, we obtain When reality appears at the zero point of the model. When using the solid channel, exclude the corresponding parameter points from the available work area; put the solid... The minimum sampling magnetic field at which the number of channels changes from non-zero to zero is defined in the operational sense. Controller selection The work sites, among which This is a margin set based on magnetic field fluctuations and model errors.

[0140] The fourth layer is the radio frequency coupling and margin feedback layer. The antenna is positioned on the vacuum side and uses a finite width... A current plate or phase-controllable array is positioned such that its tangential wavenumber spectrum center is aligned with the target. Alignment; periodic controller updates , , Operating frequency and spectral isolation margin. When frequency drift occurs, the RF frequency or array phase is corrected accordingly; when the magnetic field margin, minimum bulk attenuation margin, or ion-ion hybridization margin falls below a threshold, power is reduced and the operating point is reselected. Reflected power and port voltage are used only for safety limiting.

[0141] The parameter extension in this application is used to generate the component-magnetic field-frequency operating region and its control margin based on the source-free model. It does not include extracting candidate branches from the complex S-parameters of multiple perturbation points under the condition of freezing or de-embedding the matching network. It does not output the three-state identification results of "bound state, entering the continuous spectrum, and unconfirmed", nor does it drive selective impedance matching with the state identification results.

[0142] Thus, this application achieves its goal through source-free matching zeros, two-sided attenuation, and no real-time matching zeros. The combined screening of bulk channels and non-localized IIH layers generates a control operating region that excludes bulk propagation regions, hybrid layers, and finite-region pseudomodes; a minority ion ratio provides continuous frequency adjustment means. Under given reference conditions, as the hydrogen ratio increases from 0 to 20%, the bound state frequency continuously decreases from approximately 30.314 MHz to approximately 25.54 MHz; the minority ion ratio also changes the magnetic field conditions required for spectral isolation. Under given reference conditions, the critical magnetic field in an operational sense decreases from approximately 2.09 T for pure deuterium to approximately 1.98 T for a 20% hydrogen ratio; by solving the composition, magnetic field, radio frequency, and antenna wavenumber spectrum as a single control problem, the target interface coupling channel can be maintained when the experimental magnetic field fluctuates, the composition drifts, or the density changes; by using positive magnetic field, frequency, bulk wave attenuation, and hybrid layer distance margin control, frequency shifting, composition adjustment, magnetic field adjustment, or power reduction can be performed before the operating point approaches the bulk continuous spectrum or local hybridization conditions, while retaining reflected power and port voltage as independent safety monitoring quantities.

[0143] Corresponding to the above embodiments, this application also proposes a computer-readable storage medium.

[0144] The computer-readable storage medium of this application stores an ion cyclotron interface coupling program thereon, which, when executed by a processor, implements the aforementioned ion cyclotron interface coupling method.

[0145] It should be noted that the above explanation of the embodiments and beneficial effects of the ion cyclotron interface coupling method also applies to the computer-readable storage medium of the embodiments of this application. To avoid redundancy, it will not be elaborated in detail here.

[0146] Corresponding to the above embodiments, this application also proposes an electronic device.

[0147] The electronic device (not shown) of this application includes a memory, a processor, and an ion cyclotron interface coupling program stored in the memory and executable on the processor. When the processor executes the ion cyclotron interface coupling program, it implements the aforementioned ion cyclotron interface coupling method.

[0148] It should be noted that the above explanation of the embodiments and beneficial effects of the ion cyclotron interface coupling method also applies to the electronic devices of the embodiments of this application. To avoid redundancy, they will not be elaborated in detail here.

[0149] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0150] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0151] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0152] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0153] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0154] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A method for coupling ion cyclotron interfaces, characterized in that, include: Multiple discrete parameter combinations are determined, wherein each discrete parameter combination includes a first ion ratio, background magnetic field and electron density profile of a vacuum-plasma device, and a tangential wavenumber component of a radio frequency wave emitted by a radio frequency source; Substitute the candidate angular frequency and the discrete parameters into the propagation equation to obtain the interface matching matrix corresponding to the candidate angular frequency and the normal wavenumber at the normal position in the density transition layer. Substitute the candidate angular frequency into the cold magnetized plasma dielectric tensor to obtain the transverse diagonal parameter at the normal position in the density transition layer corresponding to the candidate angular frequency, and calculate the ion-ion hybridization margin corresponding to the candidate angular frequency based on the transverse diagonal parameter. The candidate angular frequencies are screened based on the interface matching matrix, the normal wavenumber, and the ion-ion hybridization margin, and the candidate angular frequencies that meet the preset screening conditions are determined as the bound operating point frequencies corresponding to the discrete parameter combination. A relationship table is constructed based on the bound operating point frequencies corresponding to the discrete parameter combinations. This table characterizes the correspondence between the bound operating point frequencies and the first ion ratio, the background magnetic field, the electron density profile, and the tangential wavenumber components. During operation of the vacuum-plasma device, the vacuum-plasma device and / or the radio frequency source are controlled based on the relationship table.

2. The ion cyclotron interface coupling method according to claim 1, characterized in that, The control of the vacuum-plasma device and / or the radio frequency source based on the relationship table includes: Obtain the actual first ion ratio, actual background magnetic field, and actual electron density profile of the vacuum-plasma device; The relationship table is retrieved based on the actual first ion ratio, actual background magnetic field, and actual electron density profile of the vacuum-plasma device to obtain the target confinement operating point frequency and the target tangential wavenumber component. In response to the absolute value of the frequency difference between the actual driving frequency of the radio frequency source and the target restraint operating point frequency being greater than a preset frequency threshold, the driving frequency of the radio frequency source is adjusted based on the target restraint operating point frequency. In response to the absolute value of the deviation between the tangential wavenumber component corresponding to the center of the antenna spectrum of the radio frequency source and the target tangential wavenumber component being greater than a preset deviation threshold, the center of the antenna spectrum of the radio frequency source is adjusted based on the target tangential wavenumber component.

3. The ion cyclotron interface coupling method according to claim 2, characterized in that, Also includes: Obtain the magnetic field margin, bulk spectrum isolation margin, ion-ion hybridization margin, and minimum bulk wave attenuation constant of the vacuum-plasma device; In response to the magnetic field margin being greater than a preset magnetic field margin threshold, the bulk spectrum isolation margin being greater than a preset bulk spectrum isolation threshold, the minimum bulk wave attenuation constant being less than a preset attenuation constant threshold, or the ion-ion hybridization margin being less than a preset ion-ion hybridization margin threshold, the radio frequency power of the radio frequency source is reduced, and the target confinement operating point frequency, the target tangential wavenumber component, the target background magnetic field, and the target first ion ratio are reselected based on the relationship table; The driving frequency of the radio frequency source is adjusted based on the target confinement operating point frequency, the antenna spectrum center of the radio frequency source is adjusted based on the target tangential wavenumber component, and the vacuum-plasma device is adjusted based on the target background magnetic field and the target first ion ratio.

4. The ion cyclotron interface coupling method according to claim 1, characterized in that, After constructing the relationship table based on the bound operating point frequencies corresponding to the discrete parameter combinations, the method further includes: Obtain the first ion ratio in the discrete parameter combination, and determine the operating critical magnetic field corresponding to the first ion ratio; In response to the fact that the background magnetic field in the discrete parameter combination is less than the sum of the operating critical magnetic field and the preset magnetic field margin, the discrete parameter combination is deleted from the relation table.

5. The ion cyclotron interface coupling method according to claim 4, characterized in that, The determination of the critical magnetic field corresponding to the first ion ratio includes: Multiple background magnetic fields corresponding to the first ion ratio are obtained, and background magnetic fields with bounding working point frequencies are selected from the multiple background magnetic fields. The minimum value in the background magnetic field containing the bound operating point frequency is determined as the critical operating magnetic field corresponding to the first ion ratio.

6. The ion cyclotron interface coupling method according to claim 1, characterized in that, The preset filtering conditions include: The minimum singular value of the interface matching matrix is ​​less than or equal to a first preset threshold. The number of volume propagation channels for the real normal wavenumber at the normal position within the density transition layer is zero. The ion-ion hybridization margin of the density transition layer is greater than or equal to the second preset threshold.

7. The ion cyclotron interface coupling method according to claim 1, characterized in that, The process of constructing the propagation equation includes: Along the normal of the vacuum-plasma device, the computational region is divided into multiple discrete locations according to the normal discrete step length, wherein the computational region includes a density transition layer, which is used to characterize the region where the electron density gradually increases from the boundary of the vacuum-plasma device to the plasma center; Substituting the plasma parameters at each discrete location into the multi-component Maxwell-fluid equations yields the propagation equations at the corresponding discrete locations.

8. The ion cyclotron interface coupling method according to claim 7, characterized in that, The step of substituting the candidate angular frequency and the discrete parameters into the propagation equation to obtain the interface matching matrix corresponding to the candidate angular frequency and the normal wavenumber at the normal position within the density transition layer includes: Substitute the candidate angular frequency and the discrete parameters into the propagation equation at each discrete location within the density transition layer to obtain the normal wavenumber at the normal location within the density transition layer. From the normal wavenumbers, modes that decay towards infinity along the vacuum direction are selected as vacuum-side modes, and modes that decay towards infinity along the plasma center direction are selected as plasma-side modes. Based on the preset asymptotic matching region width, a matching region is selected on the matching surface. Within the matching region, the vacuum-side mode and the plasma-side mode are spliced ​​together and normalized according to the column 2 norm to obtain the interface matching matrix corresponding to the candidate angular frequency. The matching surface is used to characterize the common spatial position where the vacuum-side mode and the plasma-side mode are spliced ​​together and the tangential electric field and tangential magnetic field continuity conditions are applied.

9. The ion cyclotron interface coupling method according to claim 8, characterized in that, The preset filtering conditions also include: The difference between the second smallest singular value and the smallest singular value of the interface matching matrix is ​​greater than the third preset threshold. The normal discrete step size and the preset asymptotic matching region width are changed respectively to obtain a new bound operating point frequency. The relative change between the new bound operating point frequency and the original bound operating point frequency is less than the preset convergence error. The attenuation constants obtained by exponential fitting of the electric field envelopes on both sides of the interface are all positive. The outer boundary of the calculation region is moved outward and the electric field distribution is recalculated to obtain the field peak position after the movement. The field peak position after the movement is the same as the field peak position before the movement. The interface is used to characterize the interface at the junction of vacuum and plasma in the vacuum-plasma device.

10. The ion cyclotron interface coupling method according to claim 1, characterized in that, Also includes: The magnetic field margin, bulk isolation margin, density deviation, and composition deviation of the vacuum-plasma device, as well as the reflected power and port voltage of the antenna port of the radio frequency source, are obtained. In response to at least one of the magnetic field margin, the bulk spectrum isolation margin, the density deviation, the component deviation, the reflected power, and the port voltage exceeding their respective preset safety thresholds, the radio frequency power of the radio frequency source is reduced or the radio frequency output of the radio frequency source is stopped.

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