A high-voltage discharge plasma element detection device

Abstract

The present application relates to the technical field of high-voltage discharge plasma, and provides a high-voltage discharge plasma element detection device, which comprises an optical platform, a discharge reaction unit, an electrical diagnosis unit and an optical diagnosis unit; the discharge reaction unit, a fiber displacement stage and an ICCD displacement stage are installed on the optical platform; the discharge reaction unit comprises a sample carrier, a supporting component, a ground electrode and a high-voltage electrode; the sample carrier is arranged on the supporting component, and the center of the sample carrier is provided with a small hole; the ground electrode is installed at the root of the optical platform and is grounded, and the needle tip of the ground electrode faces the center of the sample carrier; the high-voltage electrode is arranged above the small hole of the sample carrier, and a plurality of groups of radiating fins are installed on the high-voltage electrode; the discharge reaction unit is connected in series with a parameter adjustment dark box, and the parameter adjustment dark box is connected with a high-voltage alternating current power supply; and the present application can realize accurate regulation and control of the discharge mode and detection of metal elements in solids.

Description

Technical Field

[0001] This invention relates to the field of high-voltage discharge plasma technology, and in particular to a high-voltage discharge plasma element detection device. Background Technology

[0002] Elemental analysis is a technique used to determine the types and amounts of elements in a sample, providing crucial technical support for the development of fields such as deep space exploration, geological exploration, and environmental monitoring. Metallic elements account for more than 70% of all known elements and are common and essential in daily life. How to quickly, accurately, and conveniently detect metallic elements in real time has become an increasingly popular topic.

[0003] Methods for detecting metal elements include atomic absorption spectrometry (AAS), atomic fluorescence spectrometry (AFS), inductively coupled plasma atomic emission spectrometry (ICP-AES) / mass spectrometry (ICP-MS), laser-induced breakdown spectroscopy (LIBS), and plasma methods. Compared with traditional metal element detection techniques such as AAS, AFS, ICP-AES, ICP-MS, and LIBS, plasma detection technology has advantages such as speed, accuracy, and convenience, and has broad research prospects.

[0004] Existing research primarily focuses on detecting metal elements in solutions, mainly because the energy required to excite metal elements from solids is significantly greater than that required to excite them from liquids. The detection device typically consists of a sample digestion section, a sample introduction section, a discharge reaction section, and a sample solution circulation section. Before the experiment, the original sample must undergo sample processing and reagent preparation, which is time-consuming, labor-intensive, and prone to sample contamination. Analyzing solid samples requires these steps, which are time-consuming, labor-intensive, and inconvenient. Therefore, developing a detection technique using high-voltage discharge plasma that can directly detect metal elements in solid samples is of great significance.

[0005] There are many methods for obtaining plasma, among which pin discharge between bare electrodes is one of the most classic and simplest discharge methods for generating plasma in the atmosphere. By changing parameters such as the discharge power supply and gas environment, various discharge modes such as corona, streamer, glow, arc, and spark can be generated. Among them, arc discharge can generate highly active plasma with advantages such as high energy and high electron density, which can provide sufficient energy to excite metal elements in samples and has a bright application prospect in the field of metal element detection in solid samples. However, although discharge in atmospheric pressure air environment has the advantages of not requiring a vacuum system, simple structure, and producing a high concentration of active particles, it also faces challenges such as easy switching between discharge modes and difficulty in mode control due to factors such as sudden changes in electron temperature and fluctuations in electron density. The energy required to excite metal elements in solids is much greater than that required to excite metal elements in liquids. There is relatively little research on existing methods for detecting metal elements in solids, and most of them adopt methods such as adding auxiliary materials to the sample and adding a heating source to the device. Summary of the Invention

[0006] This invention primarily addresses the technical problems of easy discharge mode switching and difficult parameter control in existing high-voltage discharge plasma detection techniques for metal elements under atmospheric pressure. It proposes a high-voltage discharge plasma element detection device that enables precise control of the discharge mode and detection of metal elements in solids. This invention utilizes high-voltage discharge plasma between pins in an air environment to develop a detection technology that can directly detect metal elements in solid samples, which is of significant importance.

[0007] This invention provides a high-voltage discharge plasma element detection device, comprising: an optical platform, a discharge reaction unit, an electrical diagnostic unit, and an optical diagnostic unit;

[0008] The optical platform is equipped with a discharge reaction unit, an optical fiber adjustment displacement stage, and an ICCD displacement stage.

[0009] The discharge reaction unit includes: a sample carrier, a support component, a ground electrode, and a high-voltage electrode;

[0010] The sample carrier is mounted on the support component, and the sample carrier has a small hole in its center; the root of the ground electrode is mounted on the optical platform and grounded, and the tip of the ground electrode is directly facing the center of the sample carrier.

[0011] The high-voltage electrode is positioned above the small hole in the sample carrier, and multiple sets of heat sinks are mounted on the high-voltage electrode.

[0012] The discharge reaction unit is connected in series with the parameter adjustment dark box, which is connected to a high-voltage AC power supply; the electrical diagnostic unit includes a high-voltage probe, a current probe, and an oscilloscope; the high-voltage probe is located at the parameter adjustment dark box, the current probe is located at the ground electrode, and the high-voltage probe and the current probe are respectively connected to the oscilloscope;

[0013] The optical diagnostic unit includes: a dynamic evolution analysis module and a spectral analysis module;

[0014] The dynamic evolution analysis module includes: a second computer, an ICCD camera, and a trigger; the ICCD camera is fixed on an ICCD displacement stage, and the ICCD camera is connected to the trigger and the second computer respectively.

[0015] The spectral analysis module includes: a first computer, an optical fiber probe, a CCD, and a spectrometer; the optical fiber probe is fixed on an optical fiber adjustment displacement stage, and the optical fiber probe is connected in sequence to the spectrometer, the CCD, and the first computer.

[0016] Preferably, the optical platform is arranged with an array of threaded holes;

[0017] The optical platform has multiple anti-slip rubber legs underneath.

[0018] Preferably, the sample carrier is made of ceramic material.

[0019] Preferably, the support component has uniform heat dissipation holes on its wall.

[0020] Preferably, the ground electrode is fixed to the optical platform by a ground electrode fixing component.

[0021] Preferably, the high-voltage electrode is positioned above the small hole in the sample slide via a three-dimensional high-voltage electrode adjustment module.

[0022] Preferably, the high-voltage electrode is a tungsten needle with a tapered tip.

[0023] Correspondingly, the present invention also provides a detection method for a high-voltage discharge plasma element detection device according to any embodiment of the present invention, comprising the following steps:

[0024] Step 1: Place the solid sample above the small hole of the sample carrier. Use the three-dimensional high voltage electrode adjustment module to make the tip of the high voltage electrode face the center of the sample carrier. At the same time, adjust the distance between the tip of the high voltage electrode and the sample to a suitable value. Use the fiber optic adjustment displacement stage to make the fiber optic probe face the discharge reaction unit. Use the ICCD displacement stage to make the ICCD camera lens face the discharge reaction unit.

[0025] Step 2: Turn on the spectrometer, the first computer, the oscilloscope, the ICCD camera, the trigger, and the second computer; adjust the oscilloscope, CCD, and spectrometer; adjust the ICCD camera using the trigger, and adjust the ICCD camera using the second computer.

[0026] Step 3: Turn on the high-voltage AC power supply; plasma discharge begins, and a large area of ​​plasma will be generated between the high-voltage electrode and the ground electrode; observe the voltage and current waveforms and dynamic evolution images. If the discharge still does not reach the ideal mode after adjusting the power supply parameters, adjust the parameters and adjust the dark box repeatedly until the ideal discharge mode is reached; at the same time, the first computer, the second computer and the oscilloscope record the emission spectrum, dynamic evolution process and voltage and current waveforms of the high-voltage discharge plasma under the ideal parameters.

[0027] Step 4: The emission spectrum of the high-voltage discharge plasma is analyzed by the first computer to detect the elements and their relative concentrations contained in the sample.

[0028] This invention provides a high-voltage discharge plasma element detection device, comprising an integrated three-dimensional adjustable discharge reaction unit, an electrical diagnostic unit, and an optical diagnostic unit; a high-voltage AC power supply drives the high-voltage electrode discharge. The electrical and optical diagnostic units analyze the plasma characteristics under different discharge modes to select an ideal discharge mode suitable for metal element detection. Combining the diagnostic results from the electrical and optical diagnostic systems, parameters such as the dark chamber, the gap between the high-voltage and ground electrodes, and the AC excitation are adjusted to solve the problem of easy discharge mode switching, achieving precise control of discharge under atmospheric pressure air conditions. When the discharge is in the ideal discharge mode, the optical diagnostic unit detects the elements and their relative concentrations in the sample. Using this device, parameter adjustment is more convenient, discharge mode control is more precise, and the metal element detection limit is lower. This invention realizes the detection of metal elements in solids by high-voltage discharge plasma under atmospheric pressure air conditions. This invention is a system integrating control and diagnosis, providing the necessary theoretical basis for controlling the discharge mode in detection and achieving element detection in solid samples using high-voltage discharge. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the high-voltage discharge plasma element detection device provided by the present invention;

[0030] Figure 2 This is a schematic diagram of the discharge reaction unit provided by the present invention.

[0031] Reference numerals: 1. High-voltage AC power supply; 2. Fiber optic probe; 3. CCD; 4. Spectrometer; 5. First computer; 6. Parameter adjustment dark box; 7. High-voltage probe; 8. Three-dimensional high-voltage electrode adjustment module; 9. Discharge reaction unit; 10. Fiber optic adjustment displacement stage; 11. Optical platform; 12. Current probe; 13. ICCD displacement stage; 14. Oscilloscope; 15. ICCD camera; 16. Trigger; 17. Heat sink; 18. Sample carrier; 19. Support component; 20. High-voltage electrode; 21. Ground electrode fixing part; 22. Ground electrode; 23. Second computer. Detailed Implementation

[0032] To make the technical problems solved by this invention, the technical solutions adopted, and the technical effects achieved clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings, not all of them.

[0033] like Figure 1 As shown in the figure, a high-voltage discharge plasma element detection device provided in this embodiment of the invention includes: an optical platform 11, a discharge reaction unit 9, an electrical diagnostic unit, and an optical diagnostic unit.

[0034] The optical platform 11 is equipped with a discharge reaction unit 9, a fiber optic adjustment stage 10, and an ICCD stage 13, which plays a positive role in the integration of the device. The discharge reaction unit 9, fiber optic probe 2, fiber optic adjustment stage 10, ICCD camera 15, and ICCD stage 13 are all fixed on the optical platform 11. The parameter adjustment dark box 6 can also be fixed on the optical platform 11, resulting in a high degree of device integration. The placement part of the optical platform 11 is made of aluminum alloy flat plate and features an array of threaded holes, specifically 6mm in diameter and 25mm in spacing, facilitating the installation of the discharge reaction unit 9, fiber optic adjustment stage 10, and ICCD stage 13. Multiple anti-slip rubber legs are located below the optical platform 11 to isolate it from the surrounding environment.

[0035] The discharge reaction unit 9 includes a sample carrier 18, a support component 19, a ground electrode 22, and a high-voltage electrode 20. The sample carrier 18 is mounted on the support component 19 and has a small hole at its center; the sample carrier 18 is used to hold the sample and is made of ceramic. The support component 19 has uniformly distributed heat dissipation holes on its walls, allowing excess heat generated during discharge, beyond the excitation of the analyte, to dissipate quickly. Specifically, the support component 19 can be a hollow polytetrafluoroethylene cylinder with four rows of uniformly distributed heat dissipation holes on its walls. The ground electrode 22 is mounted on the optical platform 11 and grounded, with its tip facing the center of the sample carrier 18; the ground electrode 22 is fixed to the optical platform 11 by a ground electrode fixing component 21.

[0036] The high-voltage electrode 20 is positioned above the small hole in the sample carrier 18. Multiple heat sinks 17 are mounted on the high-voltage electrode 20 to quickly dissipate excess heat generated during discharge beyond the excitation of the analyte. The high-voltage electrode 20 is positioned above the small hole in the sample carrier 18 via a three-dimensional high-voltage electrode adjustment module 8. The high-voltage electrode 20 uses a tungsten needle with a tapered tip. The tungsten needle serves as the ground electrode for the discharge and is mounted on the optical platform 11 and firmly grounded. The tip of the tungsten needle faces the center of the sample carrier 18. In this embodiment, the three-dimensional high-voltage electrode adjustment module 8 has an adjustable precision of 0.01 mm and is adjustable along the XYZ axes. The XY axes are used to ensure the two electrodes are coaxial, and the Z axis is used to precisely adjust the gap between the two electrodes. This invention eliminates the need for disassembly. The three-dimensional high-voltage electrode adjustment module 8 allows for convenient adjustment of the distance and position of the high-voltage electrode 20 relative to the analyte sample, and the parameter adjustment dark box 6 allows for rapid adjustment of parameters such as the discharge capacitance and resistance. The device is highly convenient.

[0037] The discharge reaction unit 9 is connected in series with the parameter adjustment dark box 6, which is connected to the high-voltage AC power supply 1 for energy input. The high-voltage AC power supply 1 forms a high-voltage excitation unit. The parameter adjustment dark box 6 contains electrical components such as capacitor banks and current-stabilizing resistors, which allows users to adjust parameters such as capacitance and resistance while ensuring the device is neat and aesthetically pleasing.

[0038] The electrical diagnostic unit includes a high-voltage probe 7, a current probe 12, and an oscilloscope 14. The high-voltage probe 7 is located at the parameter adjustment dark box 6, and the current probe 12 is located at the ground electrode 22. The high-voltage probe 7 and the current probe 12 are respectively connected to the oscilloscope 14. The electrical characteristics of each discharge mode can be analyzed based on the voltage and current waveform diagrams, and the discharge parameters such as discharge power and energy efficiency of different modes can be further calculated.

[0039] The optical diagnostic unit includes a dynamic evolution analysis module and a spectral analysis module.

[0040] The dynamic evolution analysis module includes a second computer 23, an ICCD camera 15, and a trigger 16. The ICCD camera 15 is fixed on an ICCD displacement stage 13, and is connected to both the trigger 16 and the second computer 23. The trigger 16 sends a trigger signal to activate the ICCD camera 15. The ICCD camera 15 first converts the optical signal into an electrical signal, which is then digitized and finally converted into a digital image displayed on the second computer 23. The ICCD camera 15 is placed on the ICCD displacement stage 13, which is fixed on the optical platform 11. The ICCD displacement stage 13 facilitates camera lens adjustment and provides insulation for the equipment.

[0041] The spectral analysis module includes: fiber optic probe 2, CCD 3, spectrometer 4, and first computer 5; the fiber optic probe 2 is fixed on the fiber optic adjustment displacement stage 10, and the fiber optic probe 2 is connected in sequence to the spectrometer 4, CCD 3, and first computer 5.

[0042] The fiber optic probe 2 is fixed on the optical platform 11 by the fiber optic adjustment displacement stage 10, and its axis is directly opposite the discharge reaction unit 9. The optical signal is transmitted to the CCD 3 and the spectrometer 4 through the optical fiber, converted into an electrical signal, and then output by the first computer 5. The emission spectroscopy method is used to diagnose the particles in the discharge process. It can not only detect the type and concentration of metal elements in the solid sample being tested, but also calculate parameters such as the gas temperature and electron density of the discharge.

[0043] This invention provides a detection method for a high-voltage discharge plasma element detection device according to any embodiment of the invention, comprising the following steps:

[0044] Step 1: Place the solid sample above the small hole of the sample carrier 18. Use the three-dimensional high voltage electrode adjustment module 8 to make the tip of the high voltage electrode 20 face the center of the sample carrier 18, and at the same time adjust the distance between the tip of the high voltage electrode 20 and the sample to a suitable value. Use the fiber optic adjustment displacement stage 10 to make the fiber optic probe 2 face the discharge reaction unit 9, and use the ICCD displacement stage 13 to make the lens of the ICCD camera 15 face the discharge reaction unit 9.

[0045] Additionally, adjust the parameters of dark box 6 to set the capacitor and resistor values ​​to appropriate levels. Check that the circuit and grounding are correct.

[0046] Step 2: Turn on the spectrometer 4, the first computer 5, the oscilloscope 14, the ICCD camera 15, the trigger 16, and the second computer 23; adjust the oscilloscope 14, the CCD 3, and the spectrometer 4; adjust the ICCD camera 15 through the trigger 16, and adjust the ICCD camera 15 through the second computer 23.

[0047] Specifically, connect the high-voltage AC power supply 1, high-voltage probe 7, current probe 12, oscilloscope 14, and trigger 16. Turn on the spectrometer 4, first computer 5, oscilloscope 14, ICCD camera 15, trigger 16, and second computer 23. Adjust the voltage and current of the oscilloscope 14 to appropriate ranges. Adjust parameters such as the raster number, resolution, exposure time, and spectral acquisition range of the CCD 3 and spectrometer 4 using the control software on the first computer 5. Adjust the trigger voltage of the ICCD camera 15 using trigger 16, and adjust parameters such as the exposure time and number of frames accumulated for the ICCD camera 15 using the second computer 23.

[0048] Step 3: Turn on the high-voltage AC power supply 1; plasma discharge begins, and a large area of ​​plasma will be generated between the high-voltage electrode 20 and the ground electrode 22; observe the voltage and current waveforms and dynamic evolution images. If the discharge still does not reach the ideal mode after adjusting the power supply parameters, adjust the parameters and repeatedly experiment with the dark box 6 until the ideal discharge mode is reached; at the same time, the first computer 5, the second computer 23 and the oscilloscope 14 record the emission spectrum, dynamic evolution process and voltage and current waveforms of the high-voltage discharge plasma under the ideal parameters.

[0049] Specifically, after verifying that the circuit connections and grounding are correct, turn on the high-voltage AC power supply 1. First, adjust the AC power supply frequency, then adjust the peak-to-peak value of the input voltage. Plasma discharge begins, and a large area of ​​plasma is generated between the high-voltage electrode 20 and the ground electrode 22. Observe the voltage and current waveforms and dynamic evolution images. If adjusting the power supply parameters still does not achieve the ideal discharge mode, adjust the peak-to-peak value of the input voltage and the power supply frequency to 0, then turn off the power supply. Adjust the parameters of the dark box 6, and repeat the experiment until the ideal discharge mode is achieved. Simultaneously, the first computer 5, the second computer 23, and the oscilloscope 14 record the emission spectrum, dynamic evolution process, and voltage and current waveforms of the high-voltage discharge plasma under ideal parameters. After recording, adjust the peak-to-peak value of the input voltage and the power supply frequency to 0, turn off the high-voltage AC power supply 1, and the discharge ends.

[0050] Step 4: The emission spectrum processed by the first computer 5 is analyzed to determine the possible metallic elements and their types contained in the sample. Specifically, by analyzing the emission spectrum processed by the first computer 5, the emission intensity of the atomic spectra of different metallic elements can be obtained, thereby achieving the detection of metallic elements. Before using the high-voltage discharge plasma element detection device of this invention to detect metallic elements, the analysis curves of each element must first be determined under optimal experimental parameters, and the detection limit (LOD) of this method is calculated using the following formula.

[0051]

[0052] Where s represents the 10th standard deviation of the spectral wavelength positions of each metal element in the blank sample; k represents the slope of the standard curve.

[0053] Furthermore, important parameters such as plasma electron density, rotational temperature, vibrational temperature, electron temperature, power, power density, and energy consumption can be analyzed through emission spectra and voltage-current waveforms. These parameters provide a clear visual representation of some key characteristics of the generated plasma. Dynamic evolution images captured by the ICCD camera 15 also allow for a direct assessment of the discharge mode and its evolution.

[0054] This invention enables precise control of discharge modes and detection of metal elements in solids, and provides support for the study of the microscopic mechanisms of metal element detection and the characteristics of different discharge modes through electrical and optical diagnostic techniques.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications to the technical solutions described in the foregoing embodiments, or equivalent substitutions for some or all of the technical features, do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-voltage discharge plasma element detection device, characterized in that, include: Optical platform (11), discharge reaction unit (9), electrical diagnostic unit and optical diagnostic unit; The optical platform (11) is equipped with a discharge reaction unit (9), an optical fiber adjustment displacement stage (10), and an ICCD displacement stage (13); The discharge reaction unit (9) includes: a sample carrier (18), a support component (19), a ground electrode (22), and a high-voltage electrode (20); The sample carrier (18) is mounted on the support component (19), and the sample carrier (18) has a small hole in the center; the root of the ground electrode (22) is mounted on the optical platform (11) and grounded, and the tip of the ground electrode (22) is directly opposite the center of the sample carrier (18); The high-voltage electrode (20) is disposed above the small hole of the sample carrier (18), and multiple sets of heat sinks (17) are installed on the high-voltage electrode (20); The discharge reaction unit (9) is connected in series with the parameter adjustment dark box (6), and the parameter adjustment dark box (6) is connected to the high-voltage AC power supply (1); the electrical diagnostic unit includes: a high-voltage probe (7), a current probe (12) and an oscilloscope (14); the high-voltage probe (7) is set at the parameter adjustment dark box (6), the current probe (12) is set at the ground electrode (22), and the high-voltage probe (7) and the current probe (12) are respectively connected to the oscilloscope (14); The optical diagnostic unit includes: a dynamic evolution analysis module and a spectral analysis module; The dynamic evolution analysis module includes: a second computer (23), an ICCD camera (15), and a trigger (16); the ICCD camera (15) is fixed on an ICCD displacement stage (13), and the ICCD camera (15) is connected to the trigger (16) and the second computer (23) respectively. The spectral analysis module includes: a first computer (5), an optical fiber probe (2), a CCD (3), and a spectrometer (4); the optical fiber probe (2) is fixed on an optical fiber adjustment displacement stage (10), and the optical fiber probe (2) is connected in sequence to the spectrometer (4), the CCD (3), and the first computer (5).

2. The high-voltage discharge plasma element detection device according to claim 1, characterized in that, The optical platform (11) is arranged with an array of threaded holes; The optical platform (11) has multiple anti-slip rubber legs underneath.

3. The high-voltage discharge plasma element detection device according to claim 1, characterized in that, The sample plate (18) is made of ceramic material.

4. The high-voltage discharge plasma element detection device according to claim 1, characterized in that, The support component (19) has uniform heat dissipation holes on its wall.

5. The high-voltage discharge plasma element detection device according to claim 1, characterized in that, The ground electrode (22) is fixed on the optical platform (11) by the ground electrode fixing part (21).

6. The high-voltage discharge plasma element detection device according to claim 1, characterized in that, The high-voltage electrode (20) is positioned above the small hole on the sample plate (18) via a three-dimensional high-voltage electrode adjustment module (8).

7. The high-voltage discharge plasma element detection device according to claim 6, characterized in that, The high-voltage electrode (20) is a tungsten needle with a tapered tip.

8. A detection method for a high-voltage discharge plasma element detection device according to any one of claims 1 to 7, characterized in that, The process includes the following: Step 1: Place the solid sample above the small hole of the sample carrier (18), use the three-dimensional high voltage electrode adjustment module (8) to make the tip of the high voltage electrode (20) face the center of the sample carrier (18), and at the same time adjust the distance from the tip of the high voltage electrode (20) to the sample to a suitable value; use the fiber optic adjustment displacement stage (10) to make the fiber optic probe (2) face the discharge reaction unit (9), and use the ICCD displacement stage (13) to make the lens of the ICCD camera (15) face the discharge reaction unit (9); Step 2: Turn on the spectrometer (4), the first computer (5), the oscilloscope (14), the ICCD camera (15), the trigger (16), and the second computer (23); adjust the oscilloscope (14), the CCD (3), and the spectrometer (4); adjust the ICCD camera (15) through the trigger (16), and adjust the ICCD camera (15) through the second computer (23); Step 3, turn on the high-voltage AC power supply (1); plasma discharge begins, and a large area of ​​plasma will be generated between the high-voltage electrode (20) and the ground electrode (22); Observe the voltage and current waveforms and dynamic evolution images. If the discharge still does not reach the ideal mode after adjusting the power supply parameters, adjust the parameters and adjust the dark box (6) repeatedly until the ideal discharge mode is reached. At the same time, the first computer (5), the second computer (23) and the oscilloscope (14) record the emission spectrum, dynamic evolution process and voltage and current waveform of the high-voltage discharge plasma under the ideal parameters. Step 4: The emission spectrum of the high-voltage discharge plasma is analyzed by the first computer (5) to detect the elements and relative concentrations contained in the sample.

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