A sliding arc plasma generator device coupled with microwave arc ignition

Abstract

The present invention discloses a sliding arc plasma generator device with coupled microwave arc ignition, which mainly includes a three-stage plasma generator device: a high-voltage single-electrode plasma generator, a microwave plasma generator, and a sliding arc plasma generator. The high-voltage single-electrode plasma generator and the microwave plasma generator are used in cooperation to provide arc ignition for the sliding arc plasma generator, reduce the impedance change range of the sliding arc plasma, and further reduce the difference between the no-load voltage and the loaded voltage of the sliding arc plasma driving power supply, so that the distance between the electrodes of the sliding arc plasma generator can be increased, thereby generating a high-power sliding arc plasma. Therefore, the high-power sliding arc plasma generator device with coupled microwave arc ignition of the present invention can generate a plasma with a large size and a high temperature.

Description

Technical Field

[0001] The present invention relates to the field of high-end equipment, and specifically relates to a sliding arc plasma generator device with coupled microwave arc ignition, which is used to generate large-size sliding arc plasma. Background Art

[0002] The gas temperature range of the sliding arc plasma is generally between 1500 and 4000K. It is a warm plasma, combining the advantages of cold plasma and hot plasma. Therefore, it has broad application prospects in fields such as auxiliary combustion, methane-carbon dioxide reforming, fuel cracking, and material surface treatment.

[0003] At present, there are still some problems with the sliding arc plasma that have not been solved. One of the main problems is its relatively small discharge power. The current discharge power of the sliding arc plasma is generally between 100 and 1000W. This is mainly determined by the load characteristics of the sliding arc plasma. The electrode spacing of the sliding arc plasma is gradually widened, and the shortest distance between the electrodes is generally less than 5mm, while the longest distance may exceed 100mm. This results in a huge range of impedance changes in the sliding arc plasma. When an arc is generated at the shortest distance, it shows a state of low voltage and high current, while when an arc is generated at the farthest distance, it shows a state of high voltage and low current. Generally speaking, however, the turns ratio of the primary and secondary windings of the high-voltage package of the driving power supply of the sliding arc plasma is fixed, making it difficult to match the power supply voltage requirements of the sliding arc plasma. On the premise of ensuring that the sliding arc can be broken down at the closest electrode spacing, when the arc column is stretched to a certain length, it is difficult to continue to maintain the voltage and current required for the sliding arc plasma, the sliding arc is extinguished, and the discharge power cannot be further increased.

[0004] In view of the above problems, we propose a solution to solve the arc ignition problem of the sliding arc plasma by coupling microwave plasma, so that the length of the sliding arc plasma is always maintained at a relatively long state, thereby expanding the discharge power range of the sliding plasma. Summary of the Invention

[0005] The purpose of the present invention is to provide a sliding arc plasma generator device with coupled microwave arc ignition to improve the discharge power of the sliding arc plasma.

[0006] In order to achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] A sliding arc plasma generator device coupled with microwave arc ignition, the device includes a high-voltage single-electrode plasma generator, a microwave plasma generator, and a sliding arc plasma generator; the high-voltage single-electrode plasma generator and the microwave plasma generator are coaxially fixed through a ceramic swirling gas ring, and the microwave plasma generator and the sliding arc plasma generator are coaxially fixed through an insulating ring.

[0008] Further, the high-voltage single-electrode plasma generator includes a single high-voltage electrode and a ceramic swirling gas ring. The single high-voltage electrode is made of a conical conductive metal, and the tip position of the electrode is located at the electric field peak position of the rectangular waveguide. The ceramic swirling gas ring is fixed around the single high-voltage electrode, and the central axes of the single high-voltage electrode and the ceramic swirling gas ring coincide.

[0009] Further, the microwave plasma generator includes a microwave generator, a rectangular waveguide, and an insulating ring. The rectangular waveguide is a stepped rectangular waveguide. An insulating ring made of ceramic or quartz is sleeved at the center of the λ-shaped wave along the length direction of the rectangular waveguide, and the central axis of the insulating ring coincides with the central axis of the ceramic swirling gas ring. The microwave generator is connected to the rectangular waveguide.

[0010] Further, the sliding arc plasma generator includes n pairs of knife-shaped high-voltage electrodes and 2n ceramic isolation sheets, where n is a positive integer, and the knife-shaped high-voltage electrodes and the ceramic isolation sheets are arranged alternately and symmetrically. The central axis of the sliding arc plasma generator coincides with the central axis of the ceramic swirling gas ring.

[0011] In the present invention, λ is the microwave wavelength. When the microwave plasma generator is in use, the microwave wavelength generated by the microwave generator is λ.

[0012] Further, the high-voltage single-electrode plasma generator, the microwave plasma generator, and the sliding arc plasma generator are sequentially distributed in a top, middle, and bottom manner in terms of spatial position.

[0013] In the present invention, the term "high voltage" refers to a voltage higher than 0.5 kV.

[0014] In the present invention, the term "high power" means a discharge power greater than 2 kW.

[0015] Further, the high-voltage electrode of the single high-voltage electrode plasma generator is driven by direct current, alternating current, or pulsed high voltage.

[0016] Further, the swirling angle α of the ceramic swirling gas ring is selected such that 0° ≤ α < 90°.

[0017] Further, the n pairs of high-voltage electrodes of the sliding arc plasma generator are composed of n high-voltage electrodes and n ground electrodes, where n is a positive integer.

[0018] The n pairs of high-voltage electrodes of the sliding arc plasma generator described above are driven by n independent high-voltage power supplies, and the output of the power supply can be high-voltage DC, high-frequency high-voltage AC or high-voltage pulse.

[0019] The n pairs of high-voltage electrodes of the sliding arc plasma generator described above are driven by n independent high-voltage power supplies, and the output of the power supply can be high-voltage DC, high-frequency high-voltage AC or high-voltage pulse.

[0020] Furthermore, the shortest distance d between each pair of opposed knife-shaped high-voltage electrodes is greater than 10 mm.

[0021] The beneficial effects of the present invention are as follows:

[0022] By the method of coupling microwave plasma with high-voltage single-electrode plasma, the problems that the high-voltage single-electrode plasma is easy to discharge but the plasma volume is small, and that it is difficult to initiate an arc in microwave plasma are both solved. By combining the two kinds of plasmas, microwave plasma can be more easily generated, thus providing seed electrons for igniting the sliding arc plasma, enabling the sliding arc plasma to avoid operating in a low-voltage and high-current state, and thus being able to maintain a high-voltage and high-current state all the time, thereby increasing the discharge power of the sliding arc plasma. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic structural diagram (front view) of a high-power sliding arc plasma generator device with microwave arc ignition designed by the present invention;

[0024] Figure 2 is a schematic structural diagram (top view) of a high-power sliding arc plasma generator device with microwave arc ignition designed by the present invention;

[0025] Reference numerals in the drawings: 1 high-voltage single-electrode plasma generator, 1-1 single high-voltage electrode, 1-2 ceramic gas swirling ring, 1-3 first insulating sheath, 2 microwave plasma generator, 2-1 microwave generator, 2-2 rectangular waveguide, 2-3 insulating ring, 3 sliding arc plasma generator, 3-1 knife-shaped high-voltage electrode, 3-2 ceramic isolation sheet, 3-3 second insulating sheath. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0027] According to an embodiment of the present invention, as Figure 1 shown, a high-power sliding arc plasma generator device with coupled microwave arc ignition (front view), the device includes a three-stage plasma generator: a high-voltage single-electrode plasma generator 1, a microwave plasma generator 2, and a sliding arc plasma generator 3. The high-voltage single-electrode plasma generator 1 and the microwave plasma generator 2 are coaxially fixed through a ceramic swirl gas ring 1-2, and the microwave plasma generator 2 and the sliding arc plasma generator 3 are coaxially fixed through an insulating ring 2-3. The three plasma generators are sequentially distributed in the upper, middle, and lower positions in terms of spatial location.

[0028] The high-voltage single-electrode plasma generator 1 is composed of a single high-voltage electrode 1-1, a ceramic swirl gas ring 1-2, and a first insulating sheath 1-3. The first insulating sheath 1-3 is connected to the ceramic swirl gas ring 1-2, and the first insulating sheath 1-3 is fixed above the ceramic swirl gas ring 1-2 by a threaded manner. The single high-voltage electrode 1-1 uses a conical conductive metal, and the electrode tip position is located at the electric field peak position of the rectangular waveguide 2-2, and the top of the electrode tip penetrates into the top of the rectangular waveguide 2-2. The single high-voltage electrode 1-1 is fixed with a ceramic swirl gas ring 1-2 on the periphery, and the central axes of the single high-voltage electrode 1 and the ceramic swirl gas ring 1-2 coincide.

[0029] The microwave plasma generator 2 is composed of a microwave generator 2-1, a rectangular waveguide 2-2, and an insulating ring 2-3. The rectangular waveguide 2-2 uses a stepped rectangular waveguide. Taking the λ-2 (λ is the microwave wavelength, along the length direction of the rectangular waveguide 2-2) of the rectangular waveguide 2-2 as the center, an insulating ring 2-3 such as ceramic or quartz is sleeved, and the central axis of the insulating ring 2-3 coincides with the central axis of the ceramic swirl gas ring 1-2. The microwave generator 2-1 is connected to the rectangular waveguide 2-2.

[0030] The sliding arc plasma generator 3 is composed of a knife-shaped high-voltage electrode 3-1, a ceramic isolation sheet 3-2, and a second insulating sheath 3-3. The second insulating sheath 3-3 is located directly below the rectangular waveguide and is coaxial with the insulating ring 2-3. The number of the knife-shaped high-voltage electrodes 3-1 is n pairs, and the number of the ceramic isolation sheets 3-2 is 2n, where n is a positive integer. The knife-shaped high-voltage electrodes 3-1 and the ceramic isolation sheets 3-2 are arranged in an alternating and symmetric manner, and the central axis of the sliding arc plasma generator 3 coincides with the central axis of the ceramic swirl gas ring 1-2.

[0031] The high-voltage electrode of the high-voltage single-electrode plasma generator 1 is driven by direct current, alternating current, or pulsed high voltage.

[0032] The swirl angle α of the ceramic swirl gas ring 1-2 is selected to be 0. The selection is as follows.

[0033] The n pairs of high-voltage electrodes of the sliding arc plasma generator 3 can also be composed of n high-voltage electrodes and n ground electrodes.

[0034] The n pairs of high-voltage electrodes of the sliding arc plasma generator 3 are driven by n independent high-voltage power supplies, and the output of the power supply can be high-voltage DC, high-frequency high-voltage AC or high-voltage pulse.

[0035] The n pairs of high-voltage electrodes of the sliding arc plasma generator 3 are driven by n independent high-voltage power supplies, and the output of the power supply can be high-voltage DC, high-frequency high-voltage AC or high-voltage pulse.

[0036] Figure 2 It is a high-power sliding arc plasma generator device (top view) designed by the present invention with microwave-induced arc coupling. The shortest distance d between each pair of facing knife-shaped high-voltage electrodes 3-1 needs to be greater than 10 mm.

[0037] The working principle of the device of the present invention is as follows:

[0038] (1) The ceramic swirl ring 1-2 is supplied with working gas.

[0039] (2) The high-voltage single-electrode plasma generator 1 is turned on;

[0040] (3) The microwave plasma generator 2 is turned on;

[0041] (4) The sliding arc plasma generator 3 is turned on to obtain a large-size and high-power sliding arc plasma.

[0042] As described above, only the preferred specific embodiments of the present invention are provided, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A sliding arc plasma generator device coupled with microwave arc ignition, characterized in that: The device includes a high-voltage single-electrode plasma generator, a microwave plasma generator, and a sliding arc plasma generator; the high-voltage single-electrode plasma generator and the microwave plasma generator are coaxially fixed through a ceramic swirl gas ring, and the microwave plasma generator and the sliding arc plasma generator are coaxially fixed through an insulating ring; the high-voltage single-electrode plasma generator, the microwave plasma generator, and the sliding arc plasma generator are sequentially distributed in the upper, middle, and lower positions in terms of spatial position; by coupling the high-voltage single-electrode plasma with the microwave plasma, it not only solves the problem of the small volume of the high-voltage single-electrode plasma but also solves the problem of difficult arc ignition of the microwave plasma. Through the combination of the two plasmas, it is easier to generate microwave plasma; thus, it provides seed electrons for igniting the sliding arc plasma, enabling the sliding arc plasma to avoid operating in a low-voltage and high-current state and being able to maintain a high-voltage and high-current state all the time, thereby increasing the discharge power of the sliding arc plasma.

2. The sliding arc plasma generator device with coupled microwave arc ignition according to claim 1, characterized in that: The described high-voltage single-electrode plasma generator includes a single high-voltage electrode and a ceramic swirl gas ring. The single high-voltage electrode uses a conical conductive metal, and the electrode tip position is at the electric field peak position of the rectangular waveguide. The top of the electrode tip penetrates into the top of the rectangular waveguide. The ceramic swirl gas ring is fixed around the single high-voltage electrode, and the central axes of the single high-voltage electrode and the ceramic swirl gas ring coincide.

3. The sliding arc plasma generator device with coupled microwave arc ignition according to claim 1, characterized in that: The described microwave plasma generator includes a microwave generator, a rectangular waveguide, and an insulating ring. The rectangular waveguide uses a stepped rectangular waveguide. Centered at λ / 4 along the length direction of the rectangular waveguide, a ceramic or quartz insulating ring is sleeved, and the central axis of the insulating ring coincides with the central axis of the ceramic swirl gas ring; where λ is the microwave wavelength, and the microwave is generated by the microwave generator; the central axis of the sliding arc plasma generator coincides with the central axis of the ceramic swirl gas ring.

4. A sliding arc plasma generator device with coupled microwave arc ignition according to claim 1, characterized in that: The described sliding arc plasma generator includes n pairs of knife-shaped high-voltage electrodes and 2n ceramic isolation sheets, where n is a positive integer, and the knife-shaped high-voltage electrodes and the ceramic isolation sheets are arranged in an alternating and symmetric manner.

5. A sliding arc plasma generator device with coupled microwave arc ignition, characterized in that: The high-voltage electrode of the single high-voltage electrode plasma generator is driven by direct current, alternating current, or pulsed high voltage.

6. The sliding arc plasma generator device with coupled microwave arc ignition according to claim 2, characterized in that: The swirl angle α of the ceramic swirl gas ring is selected such that 0° ≤ α < 90°.

7. A sliding arc plasma generator device with coupled microwave arc ignition according to claim 1, characterized in that: The described sliding arc plasma generator includes n pairs of high-voltage electrodes, and the n pairs of high-voltage electrodes are composed of n high-voltage electrodes and n ground electrodes, where n is a positive integer.

8. A sliding arc plasma generator device with coupled microwave arc ignition according to claim 4 or 7, characterized in that: The n pairs of high-voltage electrodes of the described sliding arc plasma generator are driven by n independent high-voltage power supplies, and the output of the power supply is high-voltage direct current, high-frequency high-voltage alternating current, or high-voltage pulse.

9. A sliding arc plasma generator device with coupled microwave arc ignition, characterized in that: The operation method of the described device is as follows: a) Pass gas into the ceramic swirl gas ring; b) Turn on the high-voltage single-electrode plasma generator; c) Turn on the microwave plasma generator; d) Turn on the sliding arc plasma generator.

10. A sliding arc plasma generator device with coupled microwave arc ignition according to claim 4, characterized in that: The shortest distance d between each pair of opposite knife-shaped high-voltage electrodes is greater than 10 mm.

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