A method and device for optoelectronic combined diagnosis of metastable time delay decoupling of oscillating plasma electron temperature
Patent Information
- Application Number
- CN202611163199.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-08-03
- Publication Date
- 2026-10-27
AI Technical Summary
[0004]本发明要解决的技术问题是针对上述现有技术的不足，而提供一种振荡等离子体电子温度的亚稳态时滞解耦光电联合诊断方法及装置，以解决传统稳态双谱线法在振荡等离子体中因亚稳态时滞效应导致的幅值畸变、相位偏移、单调性失效等问题，以及现有光电联合方案无法动态标定、探针寿命短的问题
[0044]本发明具有如下有益效果： 本发明通过同步采集同一振荡等离子体区域的朗缪尔探针电子温度真值与双通道光谱双谱线强度特征值，依托等离子体温度归一化传输函数完成模型核心参数拟合，并基于拟合参数实现工况准稳态分区判别与时滞误差动力学校正，一方面从能级动力学根源消除了传统稳态双谱线法受亚稳态时滞效应诱发的温度振荡幅值畸变、相位偏移、响应单调性失效等测量失真缺陷，另一方面依托光电同步联合标定架构解决了现有光电联合诊断方案难以动态标定模型参数、探针高侵入易损耗寿命短的短板，整套测量流程侵入扰动水平低，可适配周期性振荡等离子体全区间工况，能够实现动态电子温度的高精度、高可靠定量诊断。
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Abstract
Description
Technical Field
[0001] This invention relates to the field of plasma parameter diagnostic technology, and in particular to a metastable time-delay decoupling optoelectronic joint diagnostic method and device for oscillating plasma electron temperature. Background Technology
[0002] The dual-line emission spectroscopy method, with its advantages of being non-contact, undisturbed, and having high spatiotemporal resolution, is a core technique for diagnosing electron temperature in electrically propelled plumes and cryogenic gas discharge plasmas. Based on the steady-state Boltzmann distribution assumption, this method inverts electron temperature through the intensity ratio of characteristic spectral lines, demonstrating reliable measurement accuracy in steady-state or quasi-steady-state plasmas.
[0003] In practical engineering scenarios, such as Hall thruster breathing mode oscillation, electron cyclotron resonance ion thruster ionization oscillation, and capacitively coupled gas discharge, plasma electron temperature and density generally exhibit periodic fluctuations. Studies have shown that the energy levels on commonly used characteristic spectral lines of inert gas plasmas such as xenon and argon simultaneously have two paths: direct excitation of the ground state and metastable collisional excitation. The relaxation timescales of these two paths differ by several orders of magnitude. Under periodic oscillation conditions, this can induce a spectral line ratio time delay effect, leading to amplitude distortion and phase shift in the traditional steady-state dual-spectral-line method. At high frequencies, it can even cause monotonicity failure, resulting in a relatively large temperature measurement error, which cannot meet the high-precision temperature measurement requirements of dynamic plasmas. Current technical solutions to this problem have significant shortcomings: pure spectroscopic improvement methods do not depart from the steady-state equilibrium assumption and cannot correct metastable-mediated dynamic time delay errors from a kinetic mechanism perspective; existing optoelectronic joint diagnostic schemes only achieve static single-point calibration and have not established a dynamic calibration mechanism that is phase-locked with plasma oscillations, making it impossible to identify metastable relaxation dynamic parameters online; continuous measurement with invasive probes interferes with discharge stability and causes severe electrode ablation, while intermittent measurement cannot achieve precise phase-level synchronization with high-speed spectroscopy; at the same time, there is a lack of online discrimination and failure compensation mechanisms for temperature measurement effectiveness, resulting in low reliability of measurement results at high frequencies. Summary of the Invention
[0004] The technical problem this invention aims to solve is to address the shortcomings of the prior art by providing a metastable time-delay decoupled optoelectronic joint diagnostic method and apparatus for electron temperature in oscillating plasma. This addresses the problems of amplitude distortion, phase shift, and monotonicity failure caused by metastable time-delay effects in oscillating plasmas using the traditional steady-state dual-spectral-line method, as well as the limitations of existing optoelectronic joint schemes such as inability to dynamically calibrate and short probe lifetime. This invention's method can correct time-delay errors at the kinetic mechanism level, achieving high-precision and high-reliability measurement of electron temperature under oscillating conditions with low intrusion disturbance.
[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:
[0006] A metastable time-delay decoupled optoelectronic joint diagnostic method for oscillating plasma electron temperature includes the following:
[0007] Set the diagnostic cycle T for photoelectric combined diagnosis of oscillating plasma;
[0008] Within a diagnostic cycle T, sampling is performed at a preset interval. The true values of n electron temperatures and the characteristic values of bispectral line intensity of the oscillating plasma are continuously collected;
[0009] The normalized temperature transfer function of the oscillating plasma is established based on the dual-channel excitation dynamics model;
[0010] The core parameters in the normalized temperature transfer function are fitted using the nonlinear least squares method based on the true values of n electron temperatures;
[0011] The quasi-steady-state determination of the oscillating plasma is performed by fitting the core parameters.
[0012] If the oscillating plasma is determined to be in a quasi-steady state, the average of the n true electron temperature values is output as the diagnostic electron temperature of the oscillating plasma within one diagnostic cycle T.
[0013] If it is determined that the oscillating plasma is not in a quasi-steady state, the average value of the n true electron temperatures is corrected to obtain the corrected electron temperature, which is then output as the diagnostic electron temperature of the oscillating plasma within one diagnostic cycle T.
[0014] Repeat the above steps to complete the combined photoelectric diagnosis of the oscillating plasma in all diagnostic cycles T.
[0015] Furthermore, the normalized temperature transfer function is shown in the following equation:
[0016]
[0017] In the formula, It is the normalized temperature transfer function; It is the high-frequency sensitivity ratio of oscillating plasma; It is the imaginary unit; It is the oscillation angular frequency of the oscillating plasma; It is the metastable relaxation time of the oscillating plasma.
[0018] Furthermore, the core parameters are the high-frequency sensitivity ratio of the oscillating plasma. Metastable relaxation time and steady-state sensitivity ;
[0019] The specific details of fitting the core parameters of the normalized temperature transfer function using the nonlinear least squares method based on the true values of n electron temperatures are as follows:
[0020] By assigning values to the core parameters in the normalized temperature transfer function, the corresponding apparent temperatures are obtained. The sum of squared residuals between the apparent temperatures and the true electron temperatures is calculated. Based on the nonlinear least squares method, the core parameter values that minimize the sum of squared residuals between the apparent temperatures and the true electron temperatures are found as the final fitting results. These are the optimal fitting high-frequency sensitivity ratios. and the best-fit metastable relaxation time .
[0021] Furthermore, the specific details of the quasi-steady-state determination of the oscillating plasma are as follows:
[0022] The optimal fitting metastable relaxation time Substitute into the following formula to make a judgment.
[0023]
[0024] In the formula, It is a quasi-steady-state judgment threshold, which is an empirical value;
[0025] If the above condition is met, the oscillating plasma is considered to be in a quasi-steady state; otherwise, the oscillating plasma is not in a quasi-steady state.
[0026] Furthermore, the corrected electron temperature is obtained by correcting the average of the n true electron temperatures as follows:
[0027] The original spectral line ratio time series of the oscillating plasma is obtained by processing the n double spectral line intensity characteristic values and then performing a fast Fourier transform to obtain the original spectral line ratio frequency domain signal.
[0028] Frequency domain deconvolution correction is performed on the original spectral line ratio frequency domain signal;
[0029] The corrected original spectral line ratio frequency domain signal is subjected to inverse Fourier transform to obtain the corrected spectral line ratio time domain signal;
[0030] The corrected electron temperature is obtained by correcting the average of the true electron temperatures of n electrons by adjusting the correction spectral line ratio to the time-domain signal.
[0031] Furthermore, the specific calculation formula for the original spectral line ratio time series of the oscillating plasma is as follows:
[0032]
[0033] In the formula, It is the original spectral line ratio time series; These are the ratios of the original spectral lines calculated from the first, second to nth of the n double spectral line intensity eigenvalues; It is the j-th original spectral line ratio among n original spectral line ratios; and These are the fast-channel reference spectral line intensity and the fast-slow coupling spectral line intensity, respectively, in the j-th bispectral line intensity eigenvalue among the n bispectral line intensity eigenvalues.
[0034] Furthermore, the specific formula for frequency domain deconvolution correction is shown in the following equation.
[0035]
[0036] In the formula, It is the frequency domain signal obtained by fast Fourier transform of the original spectral line ratio and time sequence R; It is the fitted normalized temperature transfer function with the core parameter values of the optimal fit substituted; It is the original spectral line ratio frequency domain signal after correction.
[0037] Furthermore, the formula for calculating the corrected electron temperature is obtained by correcting the average of the true values of the n electron temperatures, as shown in the following equation.
[0038]
[0039] In the formula, It corrects the electron temperature; It is the average of the true values of the temperatures of n electrons; It is the corrected original spectral line ratio frequency domain signal The corrected spectral line obtained by inverse Fourier transform is compared to the time-domain signal; and These are the fast-channel instantaneous sensitivity and the slow-channel steady-state sensitivity of the oscillating plasma, respectively. It is the steady-state sensitivity of the oscillating plasma;
[0040] f1 and f2 are the contribution rates of metastable excitation paths in the energy levels of the fast-channel reference line and the fast-slow coupled line, respectively. 01 β 02 These are the temperature sensitivity coefficients for direct excitation of the ground state of oscillating plasma, β and β, respectively. m1 β m2 These are the temperature sensitivity coefficients for metastable one-step excitation of oscillating plasma, B m It is the temperature sensitivity coefficient of the metastable energy level of the oscillating plasma.
[0041] To address the aforementioned technical problems, a technical solution is also proposed:
[0042] A metastable time-delay decoupling optoelectronic joint diagnostic method and device for oscillating plasma electron temperature includes a plasma source, a plasma plume region, a Langmuir probe, an optical fiber probe, a narrowband filter array, a dual-channel spectrometer, a phase-locked synchronous trigger, and a synchronous acquisition and decoupling processing unit.
[0043] Both the fiber optic probe and the Langmuir probe are aligned with the axis of the plasma plume region, and the measurement point of the Langmuir probe coincides with the center of the field of view of the fiber optic probe. The phase-locked synchronous trigger is connected to the plasma source device, the Langmuir probe, and the dual-channel spectrometer to provide global signals. The synchronous acquisition and decoupling processing unit is connected to the Langmuir probe and the dual-channel spectrometer and receives the true value of the electrical temperature acquired by the Langmuir probe and the characteristic value of the dual spectral line intensity acquired by the dual-channel spectrometer, and performs the metastable time-delay decoupling optoelectronic joint diagnostic method for the electron temperature of oscillating plasma as described in the above technical solution.
[0044] This invention has the following beneficial effects: By synchronously acquiring the true value of the electron temperature of the Langmuir probe and the intensity characteristic value of the dual-channel spectrum of the same oscillating plasma region, this invention completes the fitting of the core parameters of the model based on the plasma temperature normalized transfer function, and realizes the quasi-steady-state partitioning discrimination and time delay error dynamic correction based on the fitted parameters. On the one hand, it eliminates the measurement distortion defects such as temperature oscillation amplitude distortion, phase shift, and response monotonicity failure induced by metastable time delay effect in the traditional steady-state dual-spectral line method from the root of energy level dynamics. On the other hand, it solves the shortcomings of existing optoelectronic joint diagnostic schemes, such as difficulty in dynamically calibrating model parameters and high probe intrusion, easy wear and short lifespan, by relying on the optoelectronic synchronous joint calibration architecture. The entire measurement process has a low level of intrusion disturbance, can be adapted to the entire range of periodic oscillating plasma conditions, and can realize high-precision and high-reliability quantitative diagnosis of dynamic electron temperature. Attached Figure Description
[0045] Figure 1 This is a schematic diagram of the system solution structure of the present invention;
[0046] Figure 2 This is a flowchart of a metastable time-delay decoupling optoelectronic joint diagnostic method for oscillating plasma electron temperature according to the present invention;
[0047] Figure 3 This is a schematic diagram comparing the electronic temperature timing before and after time delay correction.
[0048] 1 is the plasma source, 2 is the plasma plume region, 3 is the Langmuir probe, 4 is the fiber optic probe, 5 is the narrowband filter array, 6 is the dual-channel spectrometer, 7 is the phase-locked synchronous trigger, and 8 is the synchronous acquisition and decoupling processing unit. Detailed Implementation
[0049] The present invention will now be described in further detail with reference to the accompanying drawings and specific preferred embodiments.
[0050] In the description of this invention, it should be understood that the terms "left side," "right side," "upper part," "lower part," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. "First," "second," etc., do not indicate the importance of the components, and therefore should not be construed as a limitation of this invention. The specific dimensions used in this embodiment are only for illustrating the technical solution and do not limit the scope of protection of this invention.
[0051] This embodiment proposes a metastable time-delay decoupled optoelectronic joint diagnostic method for oscillating plasma electron temperature, relying on... Figure 1 The device shown is implemented as follows: Figure 1 As shown, the device includes a plasma source device 1, a plasma plume region 2, a Langmuir probe 3, an optical fiber probe 4, a narrowband filter array 5, a dual-channel spectrometer 6, a phase-locked loop (PLL) synchronous trigger 7, and a synchronous acquisition and decoupling processing unit 8. Both the optical fiber probe 4 and the Langmuir probe 3 are aligned with the axis of the plasma plume region 2, and the measurement point of the Langmuir probe 3 coincides spatially with the center of the field of view of the optical fiber probe 4. The PLL synchronous trigger 7 is connected to the plasma source device 1, the Langmuir probe 3, and the dual-channel spectrometer 6, providing a global synchronous trigger signal. The synchronous acquisition and decoupling processing unit 8 is connected to the Langmuir probe 3 and the dual-channel spectrometer 6 to perform signal acquisition and decoupling processing.
[0052] This embodiment presents a metastable time-delay decoupling optoelectronic joint diagnostic method for oscillating plasma electron temperature, such as... Figure 2 The following content is shown:
[0053] The discharge current time-domain signal of the plasma source device 1 is acquired by using the phase-locked synchronous trigger 7, and the oscillation fundamental frequency and real-time phase are extracted to establish a global synchronous time base. Two characteristic spectral lines are selected for the working fluid to be tested. The energy level on the fast channel reference spectrum is mainly excited by the ground state, and the response speed is fast and there is no time delay. The energy level on the fast-slow coupling spectrum has both ground state excitation and metastable state excitation, and the time delay effect is significant.
[0054] In this embodiment, the plasma to be tested is a xenon electrically propelled plume; the 460 nm spectral line is selected as the fast channel reference spectral line, and the 828 nm spectral line is selected as the fast-slow coupling spectral line; the narrowband filter group 5 is configured with filters of two wavelengths, and the fiber optic probe 4 adopts a small field-of-view collimation design, with the line of sight facing the plume axis, and the phase synchronization accuracy is better than 1 μs.
[0055] Within a single oscillation cycle, four uniformly distributed characteristic phase points (0°, 90°, 180°, and 270°) are selected. Based on the synchronous phase signal, the Langmuir probe 3 is pulsedly inserted into the target position of the plasma plume region 2. After a single insertion to complete a rapid voltammetric scan, it is immediately withdrawn to obtain the true electron temperature value of each phase point. The intensities of two spectral lines corresponding to the same phase are simultaneously acquired, and the spectral line intensity ratio sequence is calculated. Based on the metastable dual-channel coupled normalized temperature transfer function model, the core dynamic parameters are fitted and identified.
[0056] Specifically, the dual-channel spectrometer 6 synchronously acquires the intensities of two spectral lines corresponding to each characteristic phase point, and sends them to the synchronous acquisition and decoupling processing unit 8 to calculate the spectral line intensity ratio R:
[0057]
[0058] In the formula, I1 is the intensity of the fast channel reference spectral line, and I2 is the intensity of the fast-slow coupling spectral line.
[0059] The normalized temperature transfer function is constructed based on a dual-channel excitation kinetics model, with the fast-channel instantaneous sensitivity and the slow-channel steady-state sensitivity being as follows:
[0060]
[0061]
[0062] In the formula, f1 and f2 are the contribution rates of the metastable excitation pathways in the energy levels of the two spectral lines, respectively, and β 01 β 02 β is the temperature sensitivity coefficient for direct excitation from the ground state. m1 β m2 B is the temperature sensitivity coefficient for metastable one-step excitation. m This is the temperature sensitivity coefficient of the metastable energy level.
[0063] The overall sensitivity under steady state satisfies:
[0064]
[0065] Define high frequency sensitivity ratio Combining the metastable first-order low-pass relaxation characteristics, the normalized temperature transfer function is obtained:
[0066]
[0067] In the formula, τ m ω is the metastable relaxation time, ω=2πf is the oscillation angular frequency, and i is the imaginary unit.
[0068] Based on the true values of the electron temperatures at each phase point measured by the Langmuir probe 3, the data are sent to the synchronous acquisition and decoupling processing unit 8. The steady-state sensitivity S0 and the metastable relaxation time τ are identified through nonlinear least squares fitting. m The core parameter minimizes the sum of squared residuals between the apparent temperature calculated by the model and the true temperature of the probe.
[0069] In the preferred embodiment of this section, the Langmuir probe 3 uses a tungsten-rhenium alloy electrode, is driven by a piezoelectric telescopic mechanism, has a single insertion time of ≤1 ms, a voltage range of -30 V to +30 V, and a scanning frequency of ≥10 kHz.
[0070] The quasi-steady-state determination of the oscillating plasma is performed by substituting the fitted core parameters into the following formula.
[0071]
[0072] In the formula, It is a quasi-steady-state judgment threshold, which is an empirical value;
[0073] If the oscillating plasma is determined to be in a quasi-steady state, the average value of the true electron temperature is used as the diagnostic electron temperature of the oscillating plasma.
[0074] If it is determined that the oscillating plasma is not in a quasi-steady state, the average value of the true electron temperature is corrected to obtain the corrected electron temperature and output as the diagnostic electron temperature of the oscillating plasma.
[0075] The specific content is as follows: Dual-spectral line continuous acquisition and time-delay decoupling temperature inversion. The dual-channel spectrometer 6 continuously acquires the light intensity time series of two characteristic spectral lines at a sampling rate of not less than 1 MS / s, and calculates the original spectral line ratio time series according to equation (1); the original line ratio time series is subjected to fast Fourier transform to obtain the frequency domain signal, and frequency domain deconvolution correction is carried out based on the transfer function:
[0076]
[0077] In the formula, The frequency domain signal of the original line ratio. The frequency domain signal after correction of the line ratio.
[0078] Perform an inverse Fourier transform on the corrected frequency domain signal to obtain the time-domain correction line ratio, and substitute it into the temperature inversion formula to obtain the true electron temperature time series:
[0079]
[0080] In the formula, T e0 R0 is the steady-state electron temperature, and R0 is the steady-state line ratio.
[0081] This correction process can simultaneously eliminate amplitude distortion and phase lag caused by metastable slow channels, and suppress electron density crosstalk error.
[0082] To verify the correction effect of this method, numerical simulations were conducted based on the aforementioned dual-channel excitation kinetics transfer function model. Given the theoretically true electron temperature of periodic oscillations as input, temperature inversion was performed using both the traditional steady-state double-spectral-line method and the time-delay decoupling method of this invention. The resulting normalized electron temperature time series comparison results are as follows: Figure 3 As shown in the figure, the simulation results show that the temperature retrieved by the traditional steady-state method has significant amplitude amplification and phase lag compared to the theoretical true temperature, resulting in significant dynamic errors. The temperature corrected by the time-delay decoupling method of this invention is in high agreement with the theoretical true temperature, and both amplitude distortion and phase shift are effectively suppressed, verifying the accuracy and effectiveness of this method.
[0083] Adaptive periodic parameter updates. The pulse probe calibration process described above is repeated every set time period to update the dynamic parameters and critical frequency, adapting to the slow drift of plasma conditions. The Langmuir Probe 3 has a built-in temperature control detection unit. When the probe temperature exceeds the preset safety threshold, the system automatically extends the calibration period, reduces the frequency of probe plasma exposure, and ensures the service life and measurement safety of the Langmuir Probe 3.
[0084] This invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of this invention, various equivalent transformations can be made to the technical solution of this invention, and all such equivalent transformations fall within the protection scope of this invention.
Claims
1. A metastable time-delay decoupling optoelectronic joint diagnostic method for oscillating plasma electron temperature, characterized in that: Includes the following: Set the diagnostic cycle T for photoelectric combined diagnosis of oscillating plasma; Within a diagnostic cycle T, sampling is performed at a preset interval. The true values of n electron temperatures and the characteristic values of bispectral line intensity of the oscillating plasma are continuously collected; The normalized temperature transfer function of the oscillating plasma is established based on the dual-channel excitation dynamics model; The core parameters in the normalized temperature transfer function are fitted using the nonlinear least squares method based on the true values of n electron temperatures; The quasi-steady-state determination of the oscillating plasma is performed by fitting the core parameters. If the oscillating plasma is determined to be in a quasi-steady state, the average of the n true electron temperature values is output as the diagnostic electron temperature of the oscillating plasma within one diagnostic cycle T. If it is determined that the oscillating plasma is not in a quasi-steady state, the average value of the n true electron temperatures is corrected to obtain the corrected electron temperature, which is then output as the diagnostic electron temperature of the oscillating plasma within one diagnostic cycle T. Repeat the above steps to complete the combined photoelectric diagnosis of the oscillating plasma in all diagnostic cycles T.
2. The metastable time-delay decoupling optoelectronic joint diagnostic method for oscillating plasma electron temperature according to claim 1, characterized in that: The normalized temperature transfer function is shown in the following equation. ； In the formula, It is the normalized temperature transfer function; It is the high-frequency sensitivity ratio of oscillating plasma; It is the imaginary unit; It is the oscillation angular frequency of the oscillating plasma; It is the metastable relaxation time of the oscillating plasma.
3. The metastable time-delay decoupling optoelectronic joint diagnostic method for oscillating plasma electron temperature according to claim 2, characterized in that: The core parameters are the high-frequency sensitivity ratio of the oscillating plasma. Metastable relaxation time and steady-state sensitivity ; The specific details of fitting the core parameters of the normalized temperature transfer function using the nonlinear least squares method based on the true values of n electron temperatures are as follows: By assigning values to the core parameters in the normalized temperature transfer function, the corresponding apparent temperatures are obtained. The sum of squared residuals between the apparent temperatures and the true electron temperatures is calculated. Based on the nonlinear least squares method, the core parameter values that minimize the sum of squared residuals between the apparent temperatures and the true electron temperatures are found as the final fitting results. These are the optimal fitting high-frequency sensitivity ratios. and the best-fit metastable relaxation time .
4. The metastable time-delay decoupling optoelectronic joint diagnostic method for oscillating plasma electron temperature according to claim 3, characterized in that: The specific details of the quasi-steady-state determination for the oscillating plasma are as follows: The optimal fitting metastable relaxation time Substitute into the following formula to make a judgment. ； In the formula, It is a quasi-steady-state judgment threshold, which is an empirical value; If the above condition is met, the oscillating plasma is considered to be in a quasi-steady state; otherwise, the oscillating plasma is not in a quasi-steady state.
5. The metastable time-delay decoupling optoelectronic joint diagnostic method for oscillating plasma electron temperature according to claim 3, characterized in that: The corrected electron temperature is obtained by correcting the average of the n true electron temperature values as follows: The original spectral line ratio time series of the oscillating plasma is obtained by processing the n double spectral line intensity characteristic values and then performing a fast Fourier transform to obtain the original spectral line ratio frequency domain signal. Frequency domain deconvolution correction is performed on the original spectral line ratio frequency domain signal; The corrected original spectral line ratio frequency domain signal is subjected to inverse Fourier transform to obtain the corrected spectral line ratio time domain signal; The corrected electron temperature is obtained by correcting the average of the true electron temperatures of n electrons by adjusting the correction spectral line ratio to the time-domain signal.
6. The metastable time-delay decoupling optoelectronic joint diagnostic method for oscillating plasma electron temperature according to claim 5, characterized in that: The specific formula for calculating the original spectral line ratio time series of the oscillating plasma is as follows: ； In the formula, It is the original spectral line ratio time series; These are the ratios of the original spectral lines calculated from the first, second to nth of the n double spectral line intensity eigenvalues; It is the j-th original spectral line ratio among n original spectral line ratios; and These are the fast-channel reference spectral line intensity and the fast-slow coupling spectral line intensity, respectively, in the j-th bispectral line intensity eigenvalue among the n bispectral line intensity eigenvalues.
7. The metastable time-delay decoupling optoelectronic joint diagnostic method for oscillating plasma electron temperature according to claim 6, characterized in that: The specific formula for frequency domain deconvolution correction is shown below. ； In the formula, It is the frequency domain signal obtained by fast Fourier transform of the original spectral line ratio and time sequence R; It is the fitted normalized temperature transfer function with the core parameter values of the optimal fit substituted; It is the original spectral line ratio frequency domain signal after correction.
8. The metastable time-delay decoupling optoelectronic joint diagnostic method for oscillating plasma electron temperature according to claim 7, characterized in that: The formula for calculating the corrected electron temperature is obtained by correcting the average of the true values of n electron temperatures, as shown in the following equation. ； In the formula, It corrects the electron temperature; It is the average of the true values of the temperatures of n electrons; It is the corrected original spectral line ratio frequency domain signal The corrected spectral line obtained by inverse Fourier transform is compared to the time-domain signal; and These are the fast-channel instantaneous sensitivity and the slow-channel steady-state sensitivity of the oscillating plasma, respectively. It is the steady-state sensitivity of the oscillating plasma; f1 and f2 are the contribution rates of metastable excitation paths in the energy levels of the fast-channel reference line and the fast-slow coupled line, respectively. 01 β 02 These are the temperature sensitivity coefficients for direct excitation of the ground state of oscillating plasma, β and β, respectively. m1 β m2 These are the temperature sensitivity coefficients for metastable one-step excitation of oscillating plasma, B m It is the temperature sensitivity coefficient of the metastable energy level of the oscillating plasma.
9. An apparatus for using the metastable time-delay decoupling optoelectronic joint diagnostic method for oscillating plasma electron temperature according to any one of claims 1-8, characterized in that: It includes a plasma source, a plasma plume region, a Langmuir probe, a fiber optic probe, a narrowband filter array, a dual-channel spectrometer, a phase-locked synchronous trigger, and a synchronous acquisition and decoupling processing unit; Both the fiber optic probe and the Langmuir probe are aligned with the axis of the plasma plume region, and the measurement point of the Langmuir probe coincides with the center of the field of view of the fiber optic probe. The phase-locked synchronous trigger is connected to the plasma source device, the Langmuir probe, and the dual-channel spectrometer to provide global signals. The synchronous acquisition and decoupling processing unit is connected to the Langmuir probe and the dual-channel spectrometer and receives the true value of the electrical temperature acquired by the Langmuir probe and the characteristic value of the dual spectral line intensity acquired by the dual-channel spectrometer, and performs the metastable time-delay decoupling optoelectronic joint diagnostic method for the electron temperature of oscillating plasma as described in any one of claims 1-8.