A wide-range plasma jet generation device and method based on a pilot arc induction

Abstract

The application is based on a wide-range plasma jet generation device and method induced by a pilot arc, comprising a coaxially arranged outer electrode tube and inner electrode rod, a tungsten resonant coil, a quartz tube and a microwave source; the outer electrode tube is provided with an air inlet part, and the quartz tube is sleeved outside the inner electrode rod. The inner electrode rod is used for coupling microwave energy to the resonant coil, and by adjusting the axial relative position and gap distance between the end of the resonant coil and the end of the inner electrode rod, a high electric field coupling region is constructed therebetween, so as to generate a pilot arc to induce ionization of working gas and form a plasma jet. The application combines the mechanisms of arc ignition and field coupling maintenance, reduces the excitation threshold of plasma, realizes low-delay arc starting in a wider pressure range and frequency range and at a low starting power, improves the operation stability of a full-solid-state microwave source driving system, and is suitable for nitrogen plasma medical beauty applications driven by a full-solid-state microwave source.

Description

Technical Field

[0001] This invention relates to the technical field of plasma applications, and in particular to a device and method for generating a wide range of plasma jets based on pilot-induced arc. Background Technology

[0002] In the field of energy medicine, plasma jets are widely used for skin surface reconstruction, scar repair, and wrinkle improvement. The core principle is to utilize the reactive oxygen / nitrogen components (RONS), thermal effects, and electromagnetic fields generated by plasma to stimulate skin tissue regeneration.

[0003] Advantages and disadvantages of nitrogen as a working gas: It has relatively stable chemical properties, low acquisition cost, and unique biological effects in skin treatment. However, nitrogen molecules have extremely high ionization energy. This means that an extremely strong electric field is required to break the molecular bonds and achieve ionization when nitrogen is excited to generate plasma. Nitrogen is ionized primarily through high-field ionization and thermal ionization at extremely high temperatures.

[0004] Stable high electric fields can be generated by using microwaves operating in a standing wave state. A standing wave is formed by the superposition of two waves with the same frequency but opposite propagation directions: an incident wave and a reflected wave. At the antinodes of the standing wave, the electric field vectors of the incident and reflected waves are in the same direction, and the superposition of electric field amplitudes reaches its maximum value. Theoretically, total internal reflection occurs when there is a short circuit or open circuit, and the electric field strength at the antinodes is twice that of the traveling wave state. In local edge regions, the electric field strength and energy density are even higher. This localized enhanced electric field can be used to break down nitrogen gas and excite plasma jets. The physical spatial positions of the antinodes and nodes of a standing wave are determined by the wavelength.

[0005] Among microwave transmission devices, the coaxial bottom-feed structure meets the handheld and miniaturized requirements of medical applications. This coaxial bottom-feed structure can achieve a compact device and high energy transmission efficiency, but it is very difficult to use the energy on the ionized gas. If the impedance of the entire device is mismatched, some energy will be reflected back to the microwave source from the end of the inner electrode, resulting in energy loss.

[0006] Existing technologies include US Patent No. 6723091B2, which discloses a "Plasma Generation System for Tissue Processing"; and US Patent No. 20070073287A1, which discloses a "Plasma Processing Device Using Nitrogen as Working Gas." Physically, these patents consist of an inner electrode, an outer electrode, a dielectric material between them, and a resonant element, forming a coaxial resonant cavity. Energy is fed into the inner electrode via a microwave or radio frequency power supply, generating a strong electromagnetic field at the nozzle exit. When gas flows through this high-field-strength region, it is directly broken down by the strong electromagnetic field, generating plasma.

[0007] The existing solutions described above can generate nitrogen plasma, but there are still issues that can be improved in practical applications. This is precisely the starting point for the improvement of this invention: 1. Existing coaxial resonant cavities rely solely on the electric field at the antinodes to directly break down nitrogen gas, resulting in an excessively high power threshold and high power dependence. Breaking down nitrogen gas using electromagnetic fields requires extremely high power. This leads to large microwave power supplies with high costs.

[0008] 2. The impedance matching bandwidth is narrow, and microwave systems are extremely sensitive to minute changes. In actual surgery, even slight fluctuations in airflow or minor frequency shifts can lead to impedance mismatch, causing plasma jet delay, jet instability, or even no jet.

[0009] 3. Start-up delay: The response time from power-on to plasma ejection is relatively long. Summary of the Invention

[0010] The purpose of this invention is to solve the problems in the prior art by proposing a wide-range plasma jet generation device and method based on pilot-induced arc, so as to solve the technical problems of existing coaxial microwave plasma devices, such as ionization difficulties, strong dependence on high power, sensitivity to changes in gas pressure and frequency, and poor plasma stability.

[0011] To achieve the above objectives, the present invention proposes a wide-range plasma jet generation device based on pilot-induced arc, comprising an external electrode tube, wherein the external electrode tube has a hollow chamber inside, an air inlet communicating with the interior of the external electrode tube, an interface device at the proximal end of the external electrode tube, and a plasma outlet at the distal end. The inner electrode rod is coaxially disposed inside the outer electrode tube; A quartz tube is disposed between the inner electrode rod and the outer electrode tube, forming a channel for gas to pass through between the inner wall of the quartz tube and the inner electrode rod; A resonant coil is disposed inside the quartz tube, and the electrical length of the resonant coil is 1 / 2 of the working wavelength; A gas delivery device, wherein the gas delivery device is connected to the internal cavity of the external electrode tube; A microwave source, connected to the outer electrode tube and the inner electrode rod via the interface device, is used to provide microwave excitation energy; The inner electrode rod is used to couple microwave energy to the resonant coil, and the end of the resonant coil and the end of the inner electrode rod form a preset relative position relationship in the axial direction, and a preset gap is provided between them to construct a micro-arc discharge region with high electric field coupling. In the initial stage of excitation, the micro-arc discharge region generates a pilot arc to induce the ionization of the working gas and forms a plasma jet at the plasma outlet.

[0012] Preferably, the inner electrode rod and the resonant coil are made of tungsten metal.

[0013] Preferably, the resonant coil has a spiral structure, and its outer diameter is adapted to the inner diameter of the quartz tube to achieve radial positioning of the resonant coil within the quartz tube.

[0014] Preferably, an internal fixing component is also included. The internal fixing component is used to maintain the relative coaxial position between the inner electrode rod, the quartz tube, and the outer electrode tube. The internal fixing component includes a solid front structure and a hollow rear structure. The solid front structure is filled between the outer electrode tube and the inner electrode rod to fix the inner electrode rod and ensure its coaxiality. The hollow rear structure forms an axial ventilation channel. Its outer diameter matches the inner diameter of the outer electrode tube, and its inner diameter matches and communicates with the inner diameter of the quartz tube to guide gas flow.

[0015] Preferably, the system also includes a spiral air intake structure for cooperating with the quartz tube. The spiral air intake structure has at least two spirally distributed gas channels inside, which are used to convert axially flowing gas into rotating gas and then introduce it into the gas channels inside the quartz tube.

[0016] Preferably, the external electrode tube, internal electrode rod, quartz tube, resonant coil, and interface device together constitute a coaxial resonant cavity structure.

[0017] Preferably, the device operates at frequencies ranging from 2.40 GHz to 2.50 GHz, and the wide range of operating airflow velocities ranges from 0.1 L / min to 20.0 L / min.

[0018] Preferably, the axial relative position of the end of the resonant coil and the end of the inner electrode rod is defined such that the axial position of the end of the resonant coil does not exceed the end of the inner electrode rod, thereby ensuring spatial coupling between the two in their high electric field regions. The axial relative distance between the end of the resonant coil and the end of the inner electrode rod is 0–20 mm.

[0019] Preferably, the pilot arc is a discontinuous, instantaneous arc. After the plasma enters the stable maintenance phase, the energy of the microwave source maintains the continuous ionization of the gas through spatial electromagnetic field coupling.

[0020] Preferably, the interface device includes a female thread at the end of the external electrode tube, a central conductor socket at the center of the female thread, and a dielectric insulating layer inside the female thread. One end of the internal electrode rod is inserted into the central conductor socket to achieve electrical connection with the microwave source radio frequency signal.

[0021] Another object of the present invention is to provide a method for generating plasma using the wide-range plasma jet generation device based on pilot-induced arc as described in any of the above claims, characterized by comprising the following steps: A working gas is introduced into the external electrode tube; When the microwave source is turned on, a pilot arc is generated in the micro-arc discharge region through electromagnetic coupling between the inner electrode rod and the resonant coil. The pilot conductive arc is used to induce an avalanche ionization process in the working gas, forming an initial plasma. By adjusting the microwave power and gas pressure, the plasma enters a stable jet phase maintained by the space electromagnetic field.

[0022] The present invention leverages the advantages of a wide-range plasma jet generation device and method induced by a pilot-charge arc: By introducing a "pilot-charge arc induction" mechanism, specifically utilizing a tungsten wire spring coil coupled to an inner electrode microwave, two high electric fields are generated at the end of the inner electrode and the distal end of the tungsten coil. These two high-intensity local electric fields excite an arc that ignites nitrogen gas. The ionized nitrogen ions are propelled by the gas flow, expanding the conductive range at the end of the inner electrode and forming a larger high-electric-field region, further inducing the formation of a nitrogen plasma flow. The induced plasma flow transforms the entire structure from a high-impedance to a 50Ω impedance load conductor. The stability of the ion flow is maintained by field coupling, significantly reducing the start-up power and breakdown threshold required for gas ionization.

[0023] This invention constructs a stable high-electric-field coupling region by adjusting the axial relative position of the inner electrode rod and the end of the resonant coil. During continuous operation, the resonant frequency can be stably maintained. This achieves low-delay arc initiation to generate a plasma jet and improves operational stability under different operating parameters.

[0024] Enhance the continuity and stability of the plasma jet. To make the jet more suitable for medical aesthetics, it can be used in precision scenarios such as skin reconstruction and scar repair. This invention transforms the airflow from axial to rotational by setting up a spiral gas guiding structure. This design enhances the uniformity and stability of the plasma jet and broadens the operating bandwidth of the device under different gas pressures and frequencies.

[0025] It is suitable for stable plasma generation under low-power microwave source driving conditions, and is especially suitable for medical and cosmetic applications using high-ionization energy gases such as nitrogen.

[0026] The features and advantages of the present invention will be described in detail through embodiments and in conjunction with the accompanying drawings. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the overall three-dimensional structure of the wide-range plasma jet generation device based on pilot-induced electric arc of the present invention.

[0028] Figure 2 yes Figure 1 Partial cross-sectional structural diagram.

[0029] Figure 3 This is a schematic diagram of the axial cross-sectional structure of the invention, which is based on a wide-range plasma jet generation device induced by a pilot-charged electric arc.

[0030] Figure 4 This is a partially enlarged schematic diagram showing the relative positional relationship between the resonant coil and the end of the inner electrode rod in an embodiment of the present invention.

[0031] Figure 5 This is a schematic diagram of the spiral air intake structure in an embodiment of the present invention.

[0032] Figure 6 This is a schematic diagram of the spiral air intake and air delivery device and internal fixing components in an embodiment of the present invention.

[0033] Figure 7 This is a schematic diagram of the plasma jet formation state when the device is working in an embodiment of the present invention.

[0034] In the figure: 1-external electrode tube, 2-quartz tube, 3-gas delivery device, 4-resonant coil, 5-inner electrode rod, 6-spiral air intake structure, 7-internal fixing component, 8-female thread, 9-center conductor socket, 10-dielectric insulation layer, 11-plasma jet. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. However, it should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0036] In the description of this invention, it should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to or indirectly connected to the other element.

[0037] In the description of this invention, it should be noted that the terms "center," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are used only for the convenience of describing the invention and for 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. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. "Several" means one or more, unless otherwise explicitly specified.

[0038] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set", "install", "connect", and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components. "Wide range" means that the working airflow velocity can be from 0.1 L / min to 5.0 L / min and the working frequency can be from 2.40 GHz to 2.5 GHz, and the operation can be stable.

[0039] Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances. Example 1:

[0040] See Figures 1-3 The present invention is based on a wide-range plasma jet generation device induced by a pilot-charge arc, comprising a microwave source and a plasma generating structure. The microwave source is connected to the plasma generating structure via a coaxial cable to provide microwave excitation energy. like Figures 2-4 As shown, the coaxial transmission structure includes an outer electrode tube 1 and an inner electrode rod 5. The outer electrode tube 1 is a hollow metal tube structure, one end of which is detachably connected to a coaxial connector through an N-type female thread 8 and electrically connected to an outer conductor to form a current loop. A plasma jet outlet is provided at the far end. The inner electrode rod 5 is arranged along the axial direction of the outer electrode tube 1 and is electrically connected to the center conductor of the coaxial cable. The inner electrode rod 5 is a metal conductor, one end of which is inserted into the center conductor socket 9 of the N-type female thread 8 to achieve electrical connection with the radio frequency signal. The radio frequency signal comes from the microwave source, and the microwave energy is transmitted to the entire device through the inner electrode rod 5.

[0041] The microwave source is connected to the outer electrode tube 1 and the inner electrode rod 5 via a coaxial cable to transmit microwave energy to the plasma generation region.

[0042] The microwave source is connected to the outer electrode tube 1 and the inner electrode rod 5 via a coaxial cable to form a coaxial transmission structure.

[0043] The plasma generating structure is located inside the external electrode tube 1 and includes an internal fixing part 7 made of plastic, a quartz tube 2, a resonant coil 4, and a gas guiding assembly.

[0044] An internal fixing component 7 is disposed between the outer electrode tube 1 and the inner electrode rod 5, preferably made of Teflon material, for coaxial positioning and electrical isolation of the inner electrode rod 5, and for adjusting the system impedance through its dielectric properties; the internal fixing component 7 includes a solid front structure and a hollow rear structure. The solid front structure fills the space between the outer electrode tube 1 and the inner electrode rod 5 to fix the inner electrode and ensure its coaxiality. The hollow rear structure forms an axial ventilation channel, the outer diameter of which matches the inner diameter of the outer electrode tube 1 and the inner diameter of which matches the inner diameter of the quartz tube 2, for guiding gas flow.

[0045] An air inlet is provided on the external electrode tube 1, and the air inlet is connected to the ventilation channel of the internal fixing component 7 so that the working gas enters the discharge area axially.

[0046] The gas delivery device 3 is connected to the air inlet of the external electrode tube 1 via a threaded connection, and is used to deliver working gas into the device.

[0047] Quartz tube 2 is located downstream of the internal fixing member 7 and coaxially nested inside the external electrode tube 1. The inner diameter of the quartz tube 2 matches the ventilation channel to form a stable discharge space and provide an electrically insulating environment.

[0048] A resonant coil 4 is disposed inside the quartz tube 2. The resonant coil 4 has a spiral tungsten wire structure, and its outer diameter matches the inner diameter of the quartz tube 2 to achieve radial limiting. The electrical length of the resonant coil 4 is set as a predetermined proportion of the working wavelength. The electrical length refers to the equivalent conductive length of the resonant coil calculated according to the electromagnetic wave at the working frequency.

[0049] The end of the resonant coil 4 near the outlet is positioned axially relative to the end of the inner electrode rod 5, ensuring that the axial position of the end of the resonant coil 4 does not exceed the end of the inner electrode rod 5, and a predetermined gap is formed between them, thus creating a pre-conduction arc triggering zone when energized. By optimizing the quartz tube diameter and introducing a built-in tungsten filament spiral coil structure, and utilizing the tip field strength gradient effect, rapid and stable ignition is achieved under low power and low airflow conditions, reducing the ignition threshold and improving discharge stability.

[0050] The gas guiding component is disposed in the ventilation channel of the internal fixing component 7. The gas guiding component is a spiral air intake structure 6 with a spiral groove structure, which is used to make the flowing working gas form a rotating flow to enhance plasma stability.

[0051] like Figure 7 As shown, during the operation of the device, the microwave energy output by the microwave source is coupled to the inner electrode rod 5 through a coaxial structure, and a high-intensity electromagnetic field is formed in the region of the resonant coil 4. In the pilot arc triggering region between the end of the inner electrode rod 5 and the end of the resonant coil 4, an instantaneous arc discharge is generated first under the concentrated action of the electric field, which is used to reduce the breakdown threshold of the working gas and induce the gas to undergo initial ionization. Subsequently, the microwave electromagnetic field is continuously coupled to the ionized gas, so that the plasma enters a stable maintenance state and is ejected from the outlet of the outer electrode tube 1 to form a plasma jet. Example 2:

[0052] like Figures 4-6 As shown, preferably, by adjusting the axial overlap length or gap distance between the end of the resonant coil 4 and the end of the inner electrode rod 5, the triggering conditions of the pilot arc can be controlled, thereby achieving adjustment of the arc initiation performance and plasma stability.

[0053] In this invention, the axial relative position of the resonant coil 4 and the inner electrode rod 5 has a decisive influence on the triggering of the pilot arc.

[0054] When the axial position of the end of the resonant coil 4 does not exceed the end of the inner electrode rod 5, based on the electromagnetic field distribution characteristics under microwave excitation conditions, the resonant coil 4 forms a region of maximum electric field intensity at its end, while the end of the inner electrode rod 5 is also a region of concentrated electric field. The two form a high-field-intensity region that is spatially coupled, thereby forming an extended high-electric-field distribution region between the end of the resonant coil 4 and the end of the inner electrode rod 5.

[0055] Within this high-field region, the local electric field strength is significantly increased, making it easier for the working gas to meet the breakdown conditions, thereby inducing a stable pilot arc discharge. Because this high-field region has a certain spatial range, it can improve the stability and repeatability of arc initiation.

[0056] Conversely, when the axial position of the end of the resonant coil 4 exceeds the end of the inner electrode rod 5, the electric field concentration area at the end of the resonant coil 4 will move away from the end of the inner electrode rod 5, causing the original coupled high field area to be destroyed, resulting in a shift in the electric field distribution. The high field strength areas cannot effectively overlap, thereby significantly increasing the difficulty of gas breakdown and reducing the probability of triggering the first conductive arc.

[0057] Therefore, by limiting the axial position of the end of the resonant coil 4 to not exceed the end of the inner electrode rod 5, a stable high-field coupling region can be effectively constructed, thereby achieving precise control over the triggering conditions of the pilot arc.

[0058] Preferably, the axial distance between the end of the resonant coil 4 and the end of the inner electrode rod 5 is 0 to 10 mm.

[0059] In addition, a preset distance is maintained between the front end of the resonant coil 4 and the spiral air intake structure 6, preferably not less than 5 mm, so as to avoid the adverse effects of the high temperature generated by the coil on the spiral air intake structure 6.

[0060] The rotation direction of the spiral channel is consistent with the spiral direction of the resonant coil 4 to enhance plasma stability.

[0061] Furthermore, the electric length of the resonant coil 4 is preferably 1 / 2 of the operating wavelength. Under this condition, the resonant coil 4 forms a typical standing wave distribution, with the two ends being the positions of maximum electric field strength and the middle part being the region of relatively low electric field strength.

[0062] By spatially coupling the high-field end of the resonant coil 4 with the end of the inner electrode rod 5, the two electric field maxima regions are superimposed in space, thereby further enhancing the local electric field strength and improving the gas ionization efficiency.

[0063] Meanwhile, the inner electrode rod 5, the outer electrode tube 1, the resonant coil 4, and the dielectric fixing structure together constitute a microwave resonant structure, enabling the system as a whole to achieve effective energy coupling in the 2.4GHz to 2.5GHz frequency band.

[0064] The microwave structure satisfies the resonance condition that the electrical length is (n+1) / 4 times the operating wavelength at the operating frequency.

[0065] The geometric parameters of the resonant coil 4 include the number of turns, wire diameter, turn spacing, and total length, which can be adjusted according to the target operating frequency so that the resonant coil 4 satisfies the resonance condition that the electrical length is in a predetermined proportion at the operating frequency.

[0066] Preferably, the output power of the microwave source is 50W to 300W, and more preferably 200W.

[0067] The N-type female thread 8 has a dielectric insulation layer 10, preferably made of Teflon, which is used to achieve electrical isolation between the center conductor socket 9 and the outer electrode tube 1. Example 3:

[0068] This embodiment proposes a wide-range plasma jet generation method based on pilot-charged arc induction for use in the above embodiments, including the following steps: A working gas is introduced into the external electrode tube 1; When the microwave source is turned on, a pilot arc is generated in the micro-arc discharge region through the electromagnetic coupling between the inner electrode rod 5 and the resonant coil 4; wherein the micro-arc discharge region is a spatial region and the pilot arc is a physical phenomenon generated in this region. The pilot conductive arc is used to induce an avalanche ionization process in the working gas, forming an initial plasma. By adjusting the microwave power and gas pressure, the plasma enters a stable jet phase maintained by the space electromagnetic field.

[0069] All standard parts used in this application can be purchased from the market. The specific connection methods of each part adopt conventional methods such as bolts, rivets, and welding that are mature in the existing technology. The internal components of the electric slide rail, cylinder, welding machine, electric telescopic rod and controller all adopt conventional models in the existing technology, and their internal structure belongs to the existing technology structure. Workers can complete the normal operation of them according to the existing technical manual. In addition, the circuit connection adopts the conventional connection method in the existing technology, and will not be described in detail here.

[0070] It should be noted that although the above embodiments have been described herein, this does not limit the scope of patent protection for this invention. Therefore, any changes and modifications made to the embodiments described herein based on the innovative concept of this invention, or equivalent structural or procedural transformations made using the description and drawings of this invention, directly or indirectly applying the above technical solutions to other related technical fields, are all included within the scope of protection of this invention.

Claims

1. A wide-range plasma jet generation device based on pilot-charged arc-induced plasma, characterized in that, include: An external electrode tube (1) is provided with a hollow chamber inside. An air inlet communicating with the interior is provided on the external electrode tube (1). An interface device is provided at the near end of the external electrode tube (1) and a plasma outlet is provided at the far end. The inner electrode rod (5) is coaxially disposed inside the outer electrode tube (1); A quartz tube (2) is disposed between the inner electrode rod (5) and the outer electrode tube (1), forming a channel for gas to pass through between the inner wall of the quartz tube (2) and the inner electrode rod (5); A resonant coil (4) is located inside the quartz tube (2), and the electrical length of the resonant coil (4) is 1 / 2 of the working wavelength; Gas delivery device (3), the gas delivery device (3) is connected to the internal cavity of the external electrode tube (1); A microwave source is connected to the outer electrode tube (1) and the inner electrode rod (5) via the interface device to provide microwave excitation energy; The inner electrode rod (5) is used to couple microwave energy to the resonant coil (4), and the end of the resonant coil (4) and the end of the inner electrode rod (5) form a preset relative position relationship in the axial direction, and a preset gap is provided between them to construct a micro-arc discharge region with high electric field coupling. In the initial stage of excitation, the micro-arc discharge region generates a pilot arc to induce the ionization of the working gas and forms a plasma jet at the plasma outlet.

2. The wide-range plasma jet generation device based on pilot-induced electric arc as described in claim 1, characterized in that: The inner electrode rod (5) and the resonant coil (4) are made of tungsten metal.

3. The wide-range plasma jet generation device based on pilot-induced arc as described in claim 1, characterized in that: The resonant coil (4) has a spiral structure and its outer diameter is adapted to the inner diameter of the quartz tube (2) so as to achieve radial positioning of the resonant coil (4) within the quartz tube (2).

4. The wide-range plasma jet generation device based on pilot-induced arc as described in claim 1, characterized in that: It also includes an internal fixing component (7), which is used to maintain the relative coaxial position between the inner electrode rod (5), the quartz tube (2) and the outer electrode tube (1). The internal fixing component (7) includes a front solid structure and a rear hollow structure. The front solid structure is filled between the outer electrode tube (1) and the inner electrode rod (5) to fix the inner electrode rod (5) and ensure its coaxiality. The rear hollow structure forms an axial ventilation channel. Its outer diameter matches the inner diameter of the outer electrode tube (1), and its inner diameter matches and connects with the inner diameter of the quartz tube (2) to guide gas flow.

5. The wide-range plasma jet generation device based on pilot-induced arc as described in claim 1, characterized in that: It also includes a spiral air intake structure (6) for cooperating with the quartz tube (2), wherein the spiral air intake structure (6) has at least two spirally distributed gas channels inside, which are used to convert axially flowing gas into rotating gas and then introduce it into the gas channels inside the quartz tube (2).

6. The wide-range plasma jet generation device based on pilot-induced electric arc as described in claim 1, characterized in that: The external electrode tube (1), the internal electrode rod (5), the quartz tube (2), the resonant coil (4), and the interface device together constitute a coaxial resonant cavity structure.

7. The wide-range plasma jet generation device based on pilot-induced arc as described in claim 1, characterized in that, The axial relative position of the end of the resonant coil (4) and the end of the inner electrode rod (5) is defined such that the axial position of the end of the resonant coil (4) does not exceed the end of the inner electrode rod (5), thereby ensuring that the high electric field regions of the two are spatially coupled. The axial relative distance between the end of the resonant coil (4) and the end of the inner electrode rod (5) is 0 to 20 mm.

8. The wide-range plasma jet generation device based on pilot-induced arc as described in claim 1, characterized in that: The pilot arc is a discontinuous, instantaneous arc. After the plasma enters the stable maintenance phase, the energy of the microwave source maintains the continuous ionization of the gas through spatial electromagnetic field coupling.

9. The wide-range plasma jet generation device based on pilot-induced arc as described in claim 1, characterized in that: The interface device includes a female thread (8) at the end of the external electrode tube (1), a central conductor socket (9) at the center of the female thread (8), and a dielectric insulating layer (10) inside the female thread (8). One end of the internal electrode rod (5) is inserted into the central conductor socket (9) to achieve electrical connection with the microwave source radio frequency signal.

10. A method for generating plasma using a wide-range plasma jet generating device based on pilot-induced arc as described in any one of claims 1-9, characterized in that, Includes the following steps: A working gas is introduced into the external electrode tube (1); Turn on the microwave source and generate a pilot arc in the micro-arc discharge region through the electromagnetic coupling between the inner electrode rod (5) and the resonant coil (4); The pilot conductive arc is used to induce an avalanche ionization process in the working gas, forming an initial plasma. By adjusting the microwave power and gas pressure, the plasma enters a stable jet phase maintained by the spatial electromagnetic field.

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