A method and system for measuring plasma current in a quasi-cyclic symmetric quasi-star device

Abstract

The application provides a kind of quasi-ring symmetry star simulator plasma current measurement method and system, it is related to star simulator technical field, including determining sensor design index according to bootstrap current simulation calculation result, and actual arrangement scheme is converted into design index according to installation environment constraint;In the state of no plasma, all magnet coils are excited separately, and the wall eddy current interference signal generated by the magnet coil is calibrated, so as to output the wall eddy current calibration voltage signal;The total original induction voltage signal including plasma current and wall eddy current is synchronously collected by using the sensor in the actual arrangement scheme;Output integral voltage signal representing total current;The integral voltage signal is compensated by using the wall eddy current calibration voltage signal, and the final measurement value of quasi-ring symmetry star simulator plasma current is inverted.The beneficial effects of the application are to weaken the interference of stray field on the measurement results, and to provide a high-precision diagnostic tool for star simulator plasma physics research.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of stellarator, in particular to a method and system for measuring plasma current in quasi-axisymmetric stellarator. BACKGROUND

[0002] The magnetic measurement system is a core component of magnetic confinement nuclear fusion research, which is used to obtain important parameters in the operation process of the device, such as magnetic field distribution, magnetic field disturbance and current distribution. The use of Rogowski coil to measure current is a key technology, which is widely used in high-precision measurement of plasma current and coil current.

[0003] In the tokamak device, the Rogowski coil current measurement technology is relatively mature, but when it is directly applied to the first quasi-axisymmetric stellarator (CFQS) in China, it faces many technical obstacles. The characteristics of CFQS determine that the plasma current is small, and there is a new classical bootstrap current, which puts forward higher requirements for the measurement accuracy and anti-interference ability of the plasma current measurement applied to CFQS. Specifically, the main technical difficulties at present include: insufficient adaptability, the traditional Rogowski coil structure is too rigid, which cannot effectively fit the compact space of the CFQS vacuum chamber, causing installation difficulties; signal amplitude problem, due to the small plasma current, the Rogowski coil signal may be lower than the signal-to-noise ratio of the back-end electronic equipment, making it difficult to ensure the stability and accuracy of the measurement; insufficient anti-interference ability, stray field and electromagnetic noise have a significant impact on the measurement accuracy, and the existing technology needs to rely on complex compensation algorithm to realize accurate measurement; limited environmental performance: the running environment of CFQS is complex, including high temperature, high vacuum and strong electromagnetic interference, which puts high requirements on the material and structure design of the measurement module. SUMMARY

[0004] The purpose of the present application is to provide a method and system for measuring plasma current in quasi-axisymmetric stellarator to improve the above problems. In order to achieve the above purpose, the technical scheme adopted by the present application is as follows:

[0005] In the first aspect, the application provides a method for measuring plasma current in quasi-axisymmetric stellarator, comprising:

[0006] According to the bootstrap current simulation calculation result, the sensor design index is determined, and the design index is converted into an actual arrangement scheme of the Rogowski coil including a flexible temperature-resistant polytetrafluoroethylene sleeve skeleton, double-layer tightly-wound temperature-resistant polyimide wire and non-magnetic stainless steel threaded pipe protection according to the installation environment constraints;

[0007] Based on the actual arrangement scheme, all the magnet coils are separately excited in the non-plasma state, the wall vortex interference signal generated by the magnet coils is calibrated, and a wall vortex calibration voltage signal is outputted;

[0008] The total original induction voltage signal including the plasma current and the wall-vortex is collected synchronously by using the sensor in the actual arrangement scheme, while the plasma discharge is performed based on the wall-vortex calibration voltage signal;

[0009] The total original induction voltage signal is input into the integrator for conversion, and the integral voltage signal representing the total current is output;

[0010] The integral voltage signal is compensated by using the wall-vortex calibration voltage signal, and the final measurement value of the plasma current in the quasi-circular symmetric stellarator is inversely calculated.

[0011] Preferably, the wall-vortex calibration voltage signal is output by separately exciting all the magnet coils in the actual arrangement scheme and calibrating the wall-vortex interference signal generated by the magnet coils in the absence of plasma.

[0012] The induction signal generated by the wall-vortex stray field is collected in real time by discharging each magnet coil one by one in the absence of plasma.

[0013] The induction signal is input into the hardware integrator with adjustable time constant as background noise, and the induction voltage is time-integrated to obtain the wall-vortex calibration voltage signal.

[0014] Preferably, the total original induction voltage signal is input into the integrator for conversion, and the integral voltage signal representing the total current is output, which includes:

[0015] The collected induction voltage signal is input into the hardware integrator with adjustable time constant. The integrator time-integrates the induction voltage, and outputs the voltage signal proportional to the size of the total toroidal current. Preferably, the integral voltage signal is compensated by using the wall-vortex calibration voltage signal, and the final measurement value of the plasma current in the quasi-circular symmetric stellarator is inversely calculated, which includes:

[0016] The total voltage output by the integrator in real time is subtracted from the calibrated wall-vortex stray field induction voltage signal to obtain the integral voltage contributed by the plasma current.

[0017] The integral voltage is multiplied by the known integral time constant and then divided by the mutual inductance coefficient of the Rogowski coil to obtain the plasma current, thereby completing the final measurement value.

[0018] The second aspect of the present application also provides a measurement system for the plasma current in a quasi-circular symmetric stellarator, which includes:

[0019] The second aspect of the present application also provides a measurement system for the plasma current in a quasi-circular symmetric stellarator, which includes:

[0020] ​Determination transformation module: used for determining sensor design index according to bootstrap current simulation calculation result, and transforming the design index into actual arrangement scheme including flexible temperature-resistant polytetrafluoroethylene sleeve framework, double-layer tightly-wound temperature-resistant polyimide winding and non-magnetic stainless steel threaded pipe protection according to installation environment constraint;

[0021] Excitation module: used for individually exciting all magnet coils in a non-plasma state based on the actual arrangement scheme, calibrating wall vortices interference signals generated by the magnet coils, so as to output wall vortices calibration voltage signals;

[0022] Collection module: used for executing plasma discharge with the wall vortices calibration voltage signals as a reference, and synchronously collecting total original induction voltage signals including plasma current and wall vortices by using the sensor in the actual arrangement scheme;

[0023] Conversion module: used for converting the total original induction voltage signals into integrator for outputting integral voltage signals representing total current;

[0024] Compensation inversion module: used for compensating the integral voltage signals by using the wall vortices calibration voltage signals, and inversely outputting final measurement values of the plasma current in the quasi-circular symmetric stellarator.

[0025] In a third aspect, the present application further provides a measurement device for plasma current in a quasi-circular symmetric stellarator, comprising:

[0026] Memory, used for storing computer programs;

[0027] Processor, used for executing the computer programs to realize the steps of the measurement method for plasma current in the quasi-circular symmetric stellarator.

[0028] In a fourth aspect, the present application further provides a readable storage medium, wherein the readable storage medium stores computer programs, and the computer programs are executed by a processor to realize the steps of the measurement method for plasma current in the quasi-circular symmetric stellarator.

[0029] The present application has the following advantages:

[0030] The module can significantly improve measurement precision, anti-interference ability and environmental adaptability by innovative structural design and optimized technical parameter setting, and meet the strict requirements of plasma current measurement in the quasi-circular symmetric stellarator during operation.

[0031] The present application not only improves the measurement precision of plasma current in the stellarator device, but also provides more reliable experimental data support for the plasma physical property research of the stellarator experiment.

[0032] The application significantly improves the measurement accuracy, environmental adaptability and reliability, and solves the problems of adaptability, accuracy and anti-interference of the traditional technology in the quasi-ring symmetric stellarator.

[0033] The coil sensitivity is significantly enhanced through the double-layer winding structure design, the measurement accuracy reaches ±5%, and the measurement range covers the plasma current of 0.01-50 kA, which fully meets the operation requirements of the CFQS; at the same time, the flexible skeleton design and compact structure effectively reduce the installation difficulty and improve the engineering feasibility; in addition, the modular design of the application combined with high-temperature insulating materials and optimized signal processing technology enables the module to operate stably in a complex high-temperature and high-vacuum environment for a long time.

[0034] The compensation algorithm of the application works in cooperation with the numerical simulation technology, greatly reduces the interference of the stray field on the measurement results, and has the significant advantages of high sensitivity, high reliability and high environmental adaptability, thereby providing a high-precision diagnostic tool for the plasma physics research of the stellarator and providing an important reference for the optimized design of other magnetic confinement devices.

[0035] Other features and advantages of the application will be described in the following description, and some of them will become apparent from the description, or will be understood by those skilled in the art through implementation of the embodiments of the application. The purposes and other advantages of the application can be achieved and obtained through the structures specifically pointed out in the written description, claims and drawings. BRIEF DESCRIPTION OF DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments, and it should be understood that the following drawings only show some of the embodiments of the application, and therefore should not be regarded as a limitation on the scope, and for those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0037] Figure 1 The flowchart of the plasma current measurement method in the quasi-ring symmetric stellarator described in the embodiments of the application is shown in the figure;

[0038] Figure 2 The structure schematic diagram of the plasma current measurement system in the quasi-ring symmetric stellarator described in the embodiments of the application is shown in the figure;

[0039] Figure 3 The structure schematic diagram of the plasma current measurement device in the quasi-ring symmetric stellarator described in the embodiments of the application is shown in the figure;

[0040] Figure 4A perspective view of spatial arrangement of a magnetic measurement system of a CFQS in a measurement method of a plasma current in a quasi-cyclic symmetric stellator according to an embodiment of the present application.

[0041] In the figure: 701, a determination conversion module; 702, an excitation module; 703, an acquisition module; 704, a conversion module; 705, a compensation inversion module; 800, a measurement device of a plasma current in a quasi-cyclic symmetric stellator; 801, a processor; 802, a memory; 803, a multimedia component; 804, an I / O interface; 805, a communication component. DETAILED DESCRIPTION

[0042] In order to make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the following will be combined with the accompanying drawings of the embodiments of the present application to make a clear and complete description of the technical solutions in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application but not all the embodiments. The components of the embodiments of the present application described and shown in the accompanying drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0043] It should be noted that: similar reference numerals and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. Meanwhile, in the description of the present application, the terms "first", "second" and the like are only used to distinguish description and cannot be understood as indicating or implying relative importance.

[0044] Embodiment 1

[0045] The embodiment provides a measurement method of a plasma current in a quasi-cyclic symmetric stellator.

[0046] Referring to Figure 1 , the figure shows that the method includes steps S100, S200, S300, S400 and S500.

[0047] S100, determine the sensor design index according to the bootstrap current simulation calculation result, and convert the design index into an actual arrangement scheme of a Rogowski coil including a flexible temperature-resistant polytetrafluoroethylene sleeve skeleton, double-layer tightly-wound temperature-resistant polyimide wire and a non-magnetic stainless steel threaded pipe protection according to the installation environment constraints.

[0048] It can be understood that the following steps are included in the present step S100:

[0049] The bootstrap current due to neoclassical transport in the quasi-axisymmetric stellarator (CFQS) configuration is calculated by solving the drift kinetic equation using the BOOTSJ code. Two density profile functions (scenarios) of the plasma are input in the BOOTSJ code:

[0050]

[0051] where ψ is the normalized magnetic flux coordinate, n(0) represents the density at the magnetic axis, <n>The average density of the body, the plasma temperature is:

[0052]

[0053] Where, the electron temperature at the magnetic axis , the ion temperature at the magnetic axis , the magnetic field strength .

[0054] Then the bootstrap current size and distribution corresponding to different density profiles are calculated by the BOOTSJ code based on the drift kinetic theory, and the formula is:

[0055]

[0056] Where, The bootstrap current density is represented by The magnetic field is represented by P, the plasma pressure, and and represent the plasma electron temperature and ion temperature, respectively, and represent the plasma electron density and ion density, respectively, is the parameter related to the device geometry obtained by VMEC (Variational Moment Equilibrium Code), ∝ ( is the capture particle fraction, is the passing particle fraction, =(1- )).

[0057] The simulation results show that the bootstrap current size in the CFQS increases linearly with the plasma body average specific pressure ( , i.e. the ratio of plasma thermal pressure to magnetic field pressure), and its order of magnitude is .

[0058] Specifically, when the in the CFQS, the plasma current is about , so the design index of the sensor is , the measurement accuracy of and the original signal amplitude requirement of more than .

[0059] The installation environment should be clearly defined: because the CFQS will perform high-temperature baking of the vacuum chamber cavity and glow discharge cleaning of the inner wall of the vacuum chamber during operation, the internal components of the vacuum chamber will be subjected to a continuous high temperature of more than 150°C. Moreover, the unique configuration design and limited geometry of the CFQS require that the Rogowski coil design be compact and flexible. To meet the measurement range of 0.01-50 kA, the measurement accuracy of ±5.0%, and the raw signal amplitude requirement of greater than 10 mV, as well as the installation environment requirement, the following scheme is adopted for the system skeleton and winding: flexible temperature-resistant polytetrafluoroethylene is selected as the winding skeleton, double-layer tightly wound polyimide insulation wire with a temperature resistance of up to 300°C is used, and non-magnetic stainless steel threaded pipe is used as the Rogowski coil protection, Figure 4 A magnetic measurement diagnostic space arrangement diagram designed on the CFQS is shown, in which the arrangement of the Rogowski coil and the text annotation are highlighted in red.

[0060] This step enhances the flexibility of the coil to adapt to the compact installation space, and the double-layer winding process makes the coil and the plasma farther apart, ensuring the stability of the work in the high-temperature high-vacuum environment.

[0061] S200, based on the actual arrangement scheme, the magnetic coil is individually excited in the absence of plasma, and the wall vortex interference signal generated by the magnetic coil is calibrated, thereby outputting a wall vortex calibration voltage signal.

[0062] It can be understood that in this step S200, S201 and S202 are included.

[0063] S201, in the absence of plasma, the magnetic coils of the device are individually discharged, and the vacuum wall vortex induced by the magnetic coils on the wall of the vacuum chamber is , then the Rogowski coil records the stray field of the wall vortex generated by each magnetic coil on the Rogowski coil, and the calculation formula is as follows:

[0064]

[0065] In the formula, is the wall vortex stray field induction voltage signal output by the Rogowski coil, is the vacuum wall vortex, is the mutual inductance coefficient, is the differential symbol, is the differential of time;

[0066] S202, the signal data will be input as background noise into a hardware integrator with adjustable time constant , the integrator performs time integration on the induced voltage, and outputs a voltage signal proportional to the total ring voltage ​, which is subtracted in the subsequent calculation to realize the accurate measurement of the plasma current. That is, the inductive signal is taken as the background noise and input into a hardware integrator with an adjustable time constant, and then the inductive voltage is time-integrated to obtain a wall-vortex calibration voltage signal, and the calculation formula is as follows:

[0067]

[0068] In the formula, is the stray field calibration voltage signal output by the integrator, is the time constant of the integrator, is the wall-vortex stray field inductive voltage signal output by the Rogowski coil, is the mutual inductance coefficient, is the time derivative, is the vacuum wall-vortex.

[0069] S300, the inductive voltage signal of the plasma current is collected. The plasma discharge experiment is carried out under the calibrated background stray field parameter in step S2, and the toroidal plasma current is , the rapid change of which will generate an induced electromotive force in the Rogowski coil. According to Faraday's law of electromagnetic induction, the inductive voltage signal output by the Rogowski coil is proportional to the rate of change of the total current (the plasma current and the vacuum wall-vortex ) with time. That is, the wall-vortex calibration voltage signal is taken as the reference, the plasma discharge is performed, and the total original inductive voltage signal including the plasma current and the wall-vortex is synchronously collected by using the sensor in the actual arrangement scheme.

[0070] It can be understood that the inductive voltage signal of step S300 is proportional to the rate of change of the total current (the plasma current and the vacuum wall-vortex ) with time, and the calculation formula is as follows:

[0071]

[0072] In the formula, is the inductive voltage signal output by the Rogowski coil, is the plasma current, is the vacuum wall-vortex. The mutual inductance coefficient , N is the number of turns of the Rogowski coil along the toroidal direction, is the average toroidal circumference of the Rogowski coil, and S is the small cross section of the solenoid of the Rogowski coil.

[0073] According to the design parameters, when a plasma current changes in , the inductive voltage signal output by the Rogowski coil isWhen establishing within a time period, the mutual inductance coefficient is used. for The coil can generate The induced voltage has an amplitude that meets the signal-to-noise ratio requirements of the back-end electronic equipment.

[0074] S400: Input the total original induced voltage signal into the integrator for conversion, and output the integrated voltage signal representing the total current.

[0075] It is understandable that in this step S400, the induced voltage signal acquired in step S300 will be... Input to a device with an adjustable time constant In the hardware integrator, the integrator integrates the induced voltage over time and outputs the sum of the induced and circumferential total currents. Voltage signals proportional in magnitude The calculation formula is as follows:

[0076]

[0077] in, The voltage signal output by the integrator. The time constant of the integrator. This is the induced voltage signal output by the Rogowski coil. For plasma current, For vacuum wall eddy currents, mutual inductance coefficient N is the number of turns of the Rogowski coil along the circumferential direction. Let S be the average circumference of the Rogowski coil, and S be the small cross-section of the solenoid of the Rogowski coil.

[0078] For example, selecting the integrator time constant. for For a The plasma current, the voltage signal output by the integrator is This value is within the ideal range of the backend acquisition equipment. Within the measurement range.

[0079] S500 uses the wall eddy current calibration voltage signal to compensate the integrated voltage signal, and then retrieves the final measured value of the plasma current in the quasi-toroidal stellarator.

[0080] It is understood that step S500 includes S501 and S502, wherein:

[0081] S501. Subtract the total voltage output by the integrator in real time from the calibrated wall eddy current stray field induced voltage signal to obtain the integrated voltage contributed by the plasma current.

[0082] S502, the integral voltage is multiplied by a known integral time constant, and then divided by the mutual inductance coefficient of the Rogowski coil to obtain the plasma current, and the final measurement value is completed, and the calculation formula is as follows:

[0083]

[0084] In the formula, V is the voltage signal output by the integrator, V is the stray field calibration voltage signal output by the integrator, T is the time constant of the integrator, V is the induced voltage signal output by the Rogowski coil, V is the wall vortex stray field induced voltage signal output by the Rogowski coil, I is the plasma current, V is the vacuum wall vortex, is the differential of time, and M is the mutual inductance coefficient.

[0085] It should be noted that, by the double-layer winding structure design, the coil sensitivity is significantly enhanced, the measurement accuracy reaches ±5%, and the measurement range covers 0.01-50 kA of the plasma current, which fully meets the CFQS operation requirement; at the same time, the flexible skeleton design and the compact structure effectively reduce the installation difficulty and improve the engineering feasibility; in addition, the modular design of the present application combined with high-temperature insulating materials and optimized signal processing technology enables the module to operate stably in a complex high-temperature high-vacuum environment for a long time; at the same time, the compensation algorithm and the numerical simulation technology of the present application work together, which greatly reduces the interference of the stray field on the measurement result; the overall scheme has the significant advantages of high sensitivity, high reliability and high environmental adaptability, provides a high-precision diagnostic tool for plasma physics research of the quasi-star simulator, and provides an important reference for the optimization design of other magnetic confinement devices.

[0086] It should be noted that the Rogowski coil current measurement module for measuring the toroidal plasma current and the vacuum wall toroidal vortex has performance index requirements that the measurement range of the plasma current is 0.01-50 kA, and the measurement accuracy is ±5.0 %. And the measurement signal output of the Rogowski coil should be based on the amplitude range of the induced signal, which cannot be too small (less than 10 mV for a long time), and at the same time, it is not suitable to be too large (the transient pulse exceeds 20 V, which has the risk of breaking the electronic chip). From the output signal angle of the rear-end electronic equipment (integrator), the maximum output voltage is preferably 1-5 V.

[0087] Embodiment 2:

[0088] As Figure 2 shown, the present embodiment provides a plasma current measurement system in a quasi-ring-symmetric stellarator, referring to Figure 2 The system comprises:

[0089] determining transformation module 701: for determining sensor design indicators according to bootstrap current simulation calculation results, and transforming the design indicators into actual arrangement schemes including flexible temperature-resistant polytetrafluoroethylene sleeve framework, double-layer tightly-wound temperature-resistant polyimide wire, and non-magnetic stainless steel threaded pipe protection according to installation environment constraints;

[0090] excitation module 702: for individually exciting all magnet coils in a plasma-free state based on the actual arrangement scheme, calibrating wall-vortex current interference signals generated by the magnet coils, and outputting wall-vortex calibration voltage signals;

[0091] acquisition module 703: for performing plasma discharge based on the wall-vortex calibration voltage signals, and synchronously acquiring total original induction voltage signals including plasma current and wall-vortex current by using sensors in the actual arrangement scheme;

[0092] conversion module 704: for inputting the total original induction voltage signals into an integrator for conversion, and outputting integral voltage signals representing total current;

[0093] compensation and inversion module 705: for compensating the integral voltage signals by using the wall-vortex calibration voltage signals, and inverting final measurement values of the plasma current in the quasi-circularly symmetric stellarator.

[0094] Specifically, the excitation module 702 includes:

[0095] acquisition unit: for discharging each magnet coil one by one in a plasma-free state, and acquiring induction signals generated by wall-vortex stray fields in real time, the calculation formula of which is as follows:

[0096]

[0097] In the formula, is a wall-vortex stray field induction voltage signal output by a Rogowski coil, is a vacuum wall-vortex, is a mutual inductance coefficient is a differential symbol, is a differential of time;

[0098] rejection unit: for inputting the induction signals as background noise into a hardware integrator with an adjustable time constant, and then time-integrating the induction voltage to obtain wall-vortex calibration voltage signals, the calculation formula of which is as follows:

[0099]

[0100] In the formula, is a stray field calibration voltage signal output by the integrator, is a time constant of the integrator, is the wall-vortex stray field induced voltage signal output by the Rogowski coil, is the mutual inductance coefficient, is the differential of time, is the vacuum wall-vortex,

[0101] In particular, the total original induced voltage signal in the acquisition module 703 is proportional to the rate of change of the total current with time, and its calculation formula is as follows:

[0102]

[0103] In the formula, is the induced voltage signal output by the Rogowski coil, is the plasma current, is the vacuum wall-vortex, is the mutual inductance coefficient is the differential sign, is the differential of time.

[0104] The output unit: for the acquired induced voltage signal is input into a hardware integrator with adjustable time constant The integrator performs time integration on the induced voltage, and outputs a voltage signal proportional to the size of the total toroidal current , and its calculation formula is:

[0105]

[0106] In the formula, is the voltage signal output by the integrator, is the time constant of the integrator, is the induced voltage signal output by the Rogowski coil, is the plasma current, is the vacuum wall-vortex, is the mutual inductance coefficient, is the differential of time.

[0107] In particular, the compensation inversion module 705 includes:

[0108] The first calculation unit: for subtracting the wall-vortex stray field induced voltage signal calibrated from the total voltage output by the integrator in real time, to obtain the integral voltage contributed by the plasma current;

[0109] The second calculation unit: for multiplying the integral voltage by the known integral time constant, and then dividing by the mutual inductance coefficient of the Rogowski coil, to obtain the plasma current, and complete the final measurement value, and its calculation formula is as follows:

[0110] ​

[0111] wherein, Vint is the voltage signal output by the integrator, Vsh is the stray field calibration voltage signal output by the integrator, T is the time constant of the integrator, Vind is the induced voltage signal output by the Rogowski coil, Vshw is the wall current stray field induced voltage signal output by the Rogowski coil, Ip is the plasma current, Vw is the vacuum wall current is the differential of time, and M is the mutual inductance.

[0112] It should be noted that as to the system in the above-mentioned embodiments, the specific manner in which each module performs operations has been described in detail in the embodiments related to the method, and will not be described in detail here.

[0113] Embodiment 3:

[0114] Corresponding to the above method embodiments, the present embodiment also provides a plasma current measurement device in a quasi-circular symmetric stellarator. The plasma current measurement device in a quasi-circular symmetric stellarator described below can be mutually corresponding with reference to the plasma current measurement method in a quasi-circular symmetric stellarator described above.

[0115] Figure 3 FIG. 8 is a block diagram of a plasma current measurement device 800 in a quasi-circular symmetric stellarator according to an example embodiment. As shown in Figure 3 the plasma current measurement device 800 in a quasi-circular symmetric stellarator includes a processor 801 and a memory 802. The plasma current measurement device 800 in a quasi-circular symmetric stellarator also includes one or more of a multimedia component 803, an I / O interface 804, and a communication component 805.

[0116] The processor 801 is configured to control the overall operation of the quasi-circular symmetric stellarator plasma current measurement device 800 to complete all or part of the steps in the quasi-circular symmetric stellarator plasma current measurement method described above. The memory 802 is configured to store various types of data to support the operation of the quasi-circular symmetric stellarator plasma current measurement device 800, which can include, for example, instructions for any application or method operating on the quasi-circular symmetric stellarator plasma current measurement device 800, and application-related data, such as contact data, messages sent and received, pictures, audio, video, and the like. The memory 802 can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk or optical disk. The multimedia component 803 can include a screen and an audio component. The screen can be, for example, a touch screen, and the audio component is configured to output and / or input audio signals. For example, the audio component can include a microphone configured to receive external audio signals. The received audio signals can be further stored in the memory 802 or transmitted through the communication component 805. The audio component also includes at least one speaker for outputting audio signals. The I / O interface 804 provides an interface between the processor 801 and other interface modules, which can be a keyboard, mouse, or buttons, etc. These buttons can be virtual buttons or physical buttons. The communication component 805 is configured to enable wired or wireless communication between the quasi-circular symmetric stellarator plasma current measurement device 800 and other devices. Wireless communication, such as Wi-Fi, Bluetooth, near field communication (NFC), 2G, 3G or 4G, or a combination of one or more of them, so the corresponding communication component 805 can include a Wi-Fi module, a Bluetooth module or an NFC module.

[0117] In an example embodiment, the plasma current measurement device 800 in the quasi-cyclically symmetric stellarator can be implemented by one or more of an application specific integrated circuit (ASIC), a digital signal processor (DSP), a digital signal processing device (DSPD), a programmable logic device (PLD), a field programmable gate array (FPGA), a controller, a microcontroller, a microprocessor, or other electronic elements, for executing the above-mentioned quasi-cyclically symmetric stellarator plasma current measurement method.

[0118] In another example embodiment, a computer readable storage medium including program instructions is also provided, which, when executed by a processor, implements the steps of the above-mentioned quasi-cyclically symmetric stellarator plasma current measurement method. For example, the computer readable storage medium can be the above-mentioned memory 802 including program instructions, which can be executed by the processor 801 of the quasi-cyclically symmetric stellarator plasma current measurement device 800 to complete the above-mentioned quasi-cyclically symmetric stellarator plasma current measurement method.

[0119] Embodiment 4:

[0120] Corresponding to the above method embodiments, the present embodiment also provides a readable storage medium, which can be referred to in conjunction with the above-mentioned quasi-cyclically symmetric stellarator plasma current measurement method.

[0121] The computer program stored on the readable storage medium, when executed by a processor, implements the steps of the above-mentioned quasi-cyclically symmetric stellarator plasma current measurement method of the method embodiments.

[0122] The readable storage medium can be specifically a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various readable storage media that can store program codes.

[0123] The present application is different from other magnetic confinement configuration devices for measuring plasma current, which significantly improves the measurement accuracy, environmental adaptability and reliability, and solves the compatibility, accuracy and anti-interference problems of traditional technology in the quasi-cyclically symmetric stellarator.

[0124] The above merely provides the preferred embodiments of the present application, but is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

[0125] The above merely provides the preferred embodiments of the present application, but is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above merely provides the preferred embodiments of the present application, but is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.< / n>

Claims

1. A method for measuring plasma current in a quasi-toroidal stellarator, characterized in that, include: The sensor design specifications are determined based on the bootstrap current simulation calculation results, and the design specifications are transformed into an actual arrangement scheme for the Rogowski coil, which includes a flexible heat-resistant polytetrafluoroethylene sleeve skeleton, double-layer tightly wound heat-resistant polyimide winding, and non-magnetic stainless steel threaded tube protection, according to the installation environment constraints. Based on the actual layout scheme, all magnet coils are individually excited in the absence of plasma to calibrate the wall eddy current interference signal generated by the magnet coils, thereby outputting the wall eddy current calibration voltage signal. Using the wall eddy current calibration voltage signal as a reference, plasma discharge is performed, and the total original induced voltage signal, including plasma current and wall eddy current, is synchronously acquired using sensors in the actual layout scheme. The total original induced voltage signal is input into the integrator for conversion, and the output is the integrated voltage signal representing the total current; The wall eddy current calibration voltage signal is used to compensate the integrated voltage signal, and the final measured value of the plasma current in the quasi-toroidal stellarator is obtained by reversing the error. The method of using the wall eddy current calibration voltage signal to compensate the integrated voltage signal and retrieving the final measured value of the plasma current in the quasi-toroidal stellarator includes: Subtract the total voltage output by the integrator in real time from the calibrated wall eddy current stray field induced voltage signal to obtain the integrated voltage contributed by the plasma current. Multiply the integrating voltage by the known integrating time constant, and then divide by the mutual inductance coefficient of the Rogowski coil to obtain the plasma current, thus completing the final measurement. The calculation formula is as follows: In the formula, The voltage signal output by the integrator. The stray field calibration voltage signal output by the integrator. The time constant of the integrator. This is the induced voltage signal output by the Rogowski coil. The signal is the induced voltage signal from the wall eddy current stray field output by the Rogowski coil. For plasma current, It is a vacuum wall eddy current. Let M be the time derivative and M be the mutual inductance coefficient.

2. The method for measuring plasma current in a quasi-toroidal stellarator according to claim 1, characterized in that, Based on the actual arrangement scheme, all magnet coils are individually excited in a plasma-free state to calibrate the wall eddy current interference signal generated by the magnet coils, thereby outputting a wall eddy current calibration voltage signal, including: In the absence of plasma, each magnet coil is discharged sequentially, and the induced signal generated by the wall eddy current stray field is collected in real time. The calculation formula is as follows: In the formula, The signal is the induced voltage signal from the wall eddy current stray field output by the Rogowski coil. It is a vacuum wall eddy current. Mutual inductance coefficient, The differential symbol, The derivative of time; The induced signal is used as background noise and input into a hardware integrator with an adjustable time constant. The induced voltage is then integrated over time to obtain the wall eddy current calibration voltage signal, which is calculated using the following formula: In the formula, The stray field calibration voltage signal output by the integrator. The time constant of the integrator. The signal is the induced voltage signal from the wall eddy current stray field output by the Rogowski coil. Mutual inductance coefficient, For the time derivative, It is a vacuum wall vortex.

3. The method for measuring plasma current in a quasi-toroidal stellarator according to claim 1, characterized in that, The total original induced voltage signal, which includes plasma current and wall eddy current, is proportional to the rate of change of the total current over time, as calculated by the sensors synchronously acquired in the actual arrangement scheme. In the formula, This is the induced voltage signal output by the Rogowski coil. For plasma current, It is a vacuum wall eddy current. Mutual inductance coefficient, The differential symbol, It is the derivative of time.

4. The method for measuring plasma current in a quasi-toroidal stellarator according to claim 1, characterized in that, The process of inputting the total original induced voltage signal into an integrator for conversion and outputting an integrated voltage signal representing the total current includes: Acquired induced voltage signal Input to a device with an adjustable time constant In the hardware integrator, the integrator integrates the induced voltage over time and outputs the sum of the induced and circumferential total currents. Voltage signals proportional in magnitude The calculation formula is as follows: In the formula, It is the voltage signal output by the integrator. The time constant of the integrator. This is the induced voltage signal output by the Rogowski coil. For plasma current, It is a vacuum wall eddy current. Mutual inductance coefficient, It is the derivative of time.

5. A system for measuring plasma current in a quasi-toroidal stellarator, based on the method for measuring plasma current in a quasi-toroidal stellarator as described in claim 1, characterized in that, include: The conversion module is used to determine the sensor design specifications based on the bootstrap current simulation calculation results, and to convert the design specifications into an actual arrangement scheme of the Rogowski coil, including a flexible heat-resistant PTFE sleeve skeleton, double-layer tightly wound heat-resistant polyimide winding, and non-magnetic stainless steel threaded tube protection, according to the installation environment constraints. Excitation module: Used to individually excite all magnet coils in the absence of plasma based on the actual layout scheme, calibrate the wall eddy current interference signal generated by the magnet coils, and thus output the wall eddy current calibration voltage signal; Acquisition module: Used to perform plasma discharge based on the wall eddy current calibration voltage signal, and synchronously acquire the total original induced voltage signal including plasma current and wall eddy current using the sensors in the actual layout scheme; Conversion module: Used to input the total original induced voltage signal into the integrator for conversion, and output the integrated voltage signal representing the total current; Compensation and Inversion Module: Used to compensate the integrated voltage signal using the wall eddy current calibration voltage signal, and invert the final measured value of the plasma current in the quasi-toroidal stellarator; The compensation inversion module includes: The first calculation unit is used to subtract the total voltage output by the integrator in real time from the calibrated wall eddy current stray field induced voltage signal to obtain the integrated voltage contributed by the plasma current. The second calculation unit is used to multiply the integrated voltage by the known integration time constant and then divide by the mutual inductance coefficient of the Rogowski coil to obtain the plasma current, thus completing the final measurement. The calculation formula is as follows: In the formula, The voltage signal output by the integrator. The stray field calibration voltage signal output by the integrator. The time constant of the integrator. This is the induced voltage signal output by the Rogowski coil. The signal is the induced voltage signal from the wall eddy current stray field output by the Rogowski coil. For plasma current, Vacuum wall eddy current Let M be the time derivative and M be the mutual inductance coefficient.

6. The plasma current measurement system in a quasi-toroidal symmetric stellarator according to claim 5, characterized in that, The excitation module includes: Acquisition Unit: Used to discharge each magnet coil one by one in a plasma-free state, and to acquire the induced signal generated by the wall eddy current stray field in real time. The calculation formula is as follows: In the formula, The signal is the induced voltage signal from the wall eddy current stray field output by the Rogowski coil. It is a vacuum wall eddy current. Mutual inductance coefficient The differential symbol, The derivative of time; The rejection unit is used to input the induced signal as background noise into a hardware integrator with an adjustable time constant, and then integrates the induced voltage over time to obtain the wall eddy current calibration voltage signal. The calculation formula is as follows: In the formula, The stray field calibration voltage signal output by the integrator. The time constant of the integrator. The signal is the induced voltage signal from the wall eddy current stray field output by the Rogowski coil. Mutual inductance coefficient, For the time derivative, It is a vacuum wall vortex.

7. The plasma current measurement system in a quasi-toroidal stellarator according to claim 5, characterized in that, The total raw induced voltage signal in the acquisition module is proportional to the rate of change of the total current over time, and its calculation formula is as follows: In the formula, This is the induced voltage signal output by the Rogowski coil. For plasma current, It is a vacuum wall eddy current. Mutual inductance coefficient The differential symbol, It is the derivative of time.

8. The plasma current measurement system in a quasi-toroidal symmetric stellarator according to claim 5, characterized in that, The conversion module includes: Output unit: used to collect induced voltage signals Input to a device with an adjustable time constant In the hardware integrator, the integrator integrates the induced voltage over time and outputs the sum of the induced and circumferential total currents. Voltage signals proportional in magnitude The calculation formula is as follows: In the formula, It is the voltage signal output by the integrator. The time constant of the integrator. This is the induced voltage signal output by the Rogowski coil. For plasma current, It is a vacuum wall eddy current. Mutual inductance coefficient, It is the derivative of time.

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