Pulse discharge device combining Marx boost and three-axis two-cylinder transmission line

Abstract

This invention discloses a pulse discharge device combining Marx boosting and a three-axis, two-barrel transmission line. The device comprises a multi-cascaded Marx topology boosting module, a high-voltage solid-state switch, a three-axis, two-barrel interlocking pulse transmission line, and a VOCs gas discharge reaction chamber. This device addresses the challenges of high-voltage pulse generation, low efficiency, and high transmission losses in existing VOCs waste gas treatment processes.

Description

Technical Field

[0001] The invention belongs to the technical field of VOCs waste gas treatment and relates to a pulse discharge device combining Marx boosting and a three-axis two-cylinder transmission line. Background Art

[0002] Volatile organic compounds (VOCs) include various organic compounds with a boiling point below 260°C at atmospheric pressure and a saturated vapor pressure greater than 70.9 Pa at room temperature. They are a major type of waste gas that pollutes the air. In addition to being persistent and resistant to degradation in the environment, VOCs are also carcinogenic and mutagenic to humans, causing irreversible damage to human health if exposed for a long time.

[0003] Currently, technologies used to treat VOCs can be divided into recovery technologies and destruction technologies based on the treatment method. These methods mainly include absorption, adsorption, condensation, membrane separation, direct combustion, catalytic oxidation, biological treatment, and low-temperature plasma technology. Low-temperature plasma technology has been a hot research topic in the field of VOCs treatment in recent years. Its nanosecond pulse plasma discharge technology has a high VOC removal rate, which can reach 100% under certain conditions. However, in the actual application of nanosecond pulse plasma discharge to treat VOCs, the high-power pulse power supply used to generate the pulse voltage has complex manufacturing technology, high power supply cost, and the single transmission line used can only transmit no more than 50% of the pulse energy to the output end. These problems have limited the promotion and application of nanosecond pulse corona discharge to treat VOCs waste gas. Summary of the Invention

[0004] The purpose of the present invention is to provide a pulse discharge device combining Marx boost and three-axis two-cylinder transmission line, which solves the problems of difficult high voltage pulse formation, low efficiency and high transmission loss in the existing VOCs waste gas treatment process.

[0005] The technical solution adopted by the present invention is a pulse discharge device combining Marx boosting and a three-axis two-cylinder transmission line, including a multi-stage cascade Marx topology boosting module, a high-voltage solid-state switch, a three-axis two-cylinder interlocked pulse transmission line and a VOCs gas discharge reaction chamber connected in sequence.

[0006] The present invention is also characterized in that:

[0007] The multi-cascade Marx topology boost module includes a polytetrafluoroethylene insulation base, on which two rows of screw columns are arranged, and between the two rows of screw columns is a row of axial-leaded high-voltage capacitors arranged in parallel. The series discharge of the axial-leaded high-voltage capacitors is achieved by the breakdown conduction of the ball electrode spark gap switch between two adjacent parallel axial-leaded high-voltage capacitors.

[0008] In each row of screw columns, high-voltage charging resistors and high-voltage current-limiting resistors are alternately arranged between two adjacent screw columns; the two rows of screw columns are respectively connected to a DC power supply through wires.

[0009] The number of axial lead high voltage capacitors minus 1 / 2 of the number of ball electrode spark gap switches equals 1.

[0010] The high-voltage solid-state switch includes an insulating flange connection plate, which is connected to the output electrode of a multi-cascade Marx topology boost module through a metal flange connector. The output electrode of the multi-cascade Marx topology boost module is connected to the multi-cascade Marx topology boost module. One side of the insulating flange connection plate is connected to a three-axis two-cylinder interlocking pulse transmission line. The other side of the insulating flange connection plate is connected to an outer cylinder of the high-voltage solid-state switch. A surface flashover zero-potential electrode is coaxially arranged at the center of the outer cylinder of the high-voltage solid-state switch. The surface flashover zero-potential electrode is coaxially connected to a surface flashover dielectric and a surface flashover high-voltage electrode in sequence. The surface flashover high-voltage electrode is connected to the metal flange connector. A dielectric filling electrode is embedded in the surface flashover dielectric.

[0011] The three-axis two-cylinder inter-embedded pulse transmission line includes an internal solid cylindrical electrode coaxially connected to the center of the insulating flange connection disk, an intermediate shaft cylinder electrode and an external shaft cylinder electrode are coaxially arranged on the outside of the internal solid cylindrical electrode, a pulse charging inductor is connected between the internal solid cylindrical electrode and the external shaft cylinder electrode, a ring-shaped capacitor voltage divider is embedded in the external shaft cylinder electrode, and a high-frequency coaxial connector is connected to the ring-shaped capacitor voltage divider.

[0012] The ring-shaped capacitive voltage divider includes a ring base, a high-conductivity copper tape, and a polyimide tape coaxially arranged from the inside to the outside. The high-conductivity copper tape, polyimide tape, and the external cylindrical electrode form a capacitor structure; the high-conductivity copper tape, the ring base, and the internal solid cylindrical electrode form another capacitor structure.

[0013] The VOCs gas discharge reaction chamber includes a VOCs gas discharge shaft cylinder electrode coaxially arranged with an internal solid cylindrical electrode, a plasma discharge wire electrode coaxially arranged at the center of the VOCs gas discharge shaft cylinder electrode, one end of the plasma discharge wire electrode is connected to the internal solid cylindrical electrode, and the other end of the plasma discharge wire electrode is connected to a high-voltage electrode clamp, and the high-voltage electrode clamp is installed at the center of an insulating flange, and the insulating flange is connected to one end of the VOCs gas discharge shaft cylinder electrode, and the other end of the VOCs gas discharge shaft cylinder electrode is connected to the external shaft cylinder electrode through an insulating flange connector, and the internal solid cylindrical electrode is connected to the plasma discharge wire electrode through the insulating flange connector, and a high-precision current transformer is installed at the connection between the internal solid cylindrical electrode and the insulating flange connector.

[0014] The high-precision current transformer and the high-frequency coaxial connector are both connected to a high-precision digital oscilloscope.

[0015] The beneficial effects of the present invention are that the multi-cascade Marx topology boost module designed by the present invention has a simple structure and the resistors and capacitors are easy to replace. It can generate a large voltage through a simple cascade, and can maintain compactness, modularity and solidification during pulse output. The designed three-axis two-cylinder interlocking pulse transmission line has a simple and reliable structure, high output pulse waveform fidelity, can withstand high voltage and large current, and due to the presence of the intermediate axis-cylinder electrode, the parasitic coupling to the surrounding is small, and the pulse voltage transmission efficiency can reach 100% under ideal conditions. The surface discharge distance of the designed high-voltage solid-state switch can be flexibly adjusted to achieve the effect of flexibly adjusting the pulse output voltage amplitude. The discharge device of the present invention can stably generate high-voltage pulses and efficiently transmit pulse energy to the plasma discharge end, thereby improving the efficiency of VOCs waste gas treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the overall cross-sectional structure of a pulse discharge device combining Marx boosting and a three-axis two-cylinder transmission line according to the present invention;

[0017] Figure 2 It is a structural schematic diagram of a multi-cascade Marx topology boost module in a pulse discharge device combining Marx boost and a three-axis two-tube transmission line of the present invention.

[0018] Figure 3 It is a left view of a three-axis two-cylinder interlocking pulse transmission line in a pulse discharge device combining Marx boosting and a three-axis two-cylinder transmission line according to the present invention.

[0019] Figure 4 The diagram is a side cross-sectional structural diagram of a pulse discharge device combining Marx boosting and a three-axis two-drum transmission line according to the present invention, in which a ring-shaped capacitive voltage divider is installed on an external axis-drum electrode.

[0020] In the figure, 1- multi-cascade Marx topology boost module, 101- DC power supply, 102- wire, 103- screw, 104- high-voltage charging resistor, 105- axial-lead high-voltage capacitor, 106- ball electrode spark gap switch, 107- polytetrafluoroethylene insulation base, 108- high-voltage current limiting resistor;

[0021] 2-Multi-cascade Marx topology boost module output electrode, 3-High-voltage solid-state switch outer cylinder, 4-Surface flashover zero-potential electrode, 5-Dielectric-filled electrode, 6-Surface flashover dielectric, 7-Surface flashover high-voltage electrode, 8-Metal flange connector, 9-Insulating flange connection plate, 10-Internal electrode fixing base, 11-Rubber ring gasket, 12-External shaft cylinder electrode, 13-Intermediate shaft cylinder electrode, 14-Internal solid cylindrical electrode, 15-Pulse charging inductor;

[0022] 16- Ring-type capacitor voltage divider, 1601- Ring base, 1602- High conductivity copper tape, 1603- Polyimide tape, 17- High-precision current transformer, 18- Insulating flange connector, 19- Plasma discharge wire electrode, 20- VOCs gas discharge shaft tube electrode, 21- High-voltage electrode clamp, 22- Insulating flange, 23- Through-hole VOCs flow control valve, 24- Nitrile rubber screw washer, 25- Metal screw fixings, 26- High-precision digital oscilloscope, 27- High-frequency coaxial connector, 28- Through-hole dimethyl silicone oil flow control valve, 29- Through-hole SF6 flow control valve. DETAILED DESCRIPTION

[0023] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] The present invention combines the pulse discharge device of Marx boost and three-axis two-tube transmission line, such as Figure 1 As shown, it includes a multi-cascade Marx topology boost module 1, a high-voltage solid-state switch, a three-axis two-cylinder interlocking pulse transmission line, and a VOCs gas discharge reaction chamber.

[0025] The high-voltage solid-state switch includes a high-voltage solid-state switch outer tube 3, a surface flashover zero-potential electrode 4, a dielectric filling electrode 5, a surface flashover dielectric 6 and a surface flashover high-voltage electrode 7. The high-voltage solid-state switch is filled with SF6 gas. The filling and discharge of SF6 gas are controlled by two through-hole SF6 flow control valves 29 installed on the through-holes of the high-voltage solid-state switch outer tube 3, and a gas tightness test needs to be performed on the high-voltage solid-state switch gas chamber before the SF6 gas is officially introduced.

[0026] The multi-cascade Marx topology boost module 1 is connected to the multi-cascade Marx topology boost module output electrode 2 and the high-voltage solid-state switch outer cylinder 3 via wires. The multi-cascade Marx topology boost module output electrode 2 is embedded in an insulating flange connection plate 9 and connected to the surface flashover high-voltage electrode 7 through a contact metal flange connector 8. The high-voltage solid-state switch outer cylinder 3 is connected to the surface flashover zero-potential electrode 4 through a threaded connection. As required, the multi-cascade Marx topology boost module 1 outputs a voltage of nV0 to the surface flashover high-voltage electrode 7 and the surface flashover zero-potential electrode 4 in the high-voltage solid-state switch through the surface flashover dielectric 6 to cause surface discharge. The dielectric filling electrode 5 is embedded in the surface flashover dielectric 6 to make the internal electric field of the surface flashover dielectric 6 more uniform and prevent internal spatial electric field distortion.

[0027] like Figure 2 As shown, the multi-cascade Marx topology boost module 1 includes a DC power supply 101 (output voltage is V0), a wire 102, a screw 103, a high-voltage charging resistor 104, an axial-lead high-voltage capacitor 105, a ball electrode spark gap switch 106 and a polytetrafluoroethylene insulation base 107. The multi-cascade Marx topology boost module 1 charges n axial-lead high-voltage capacitors 105 in parallel and discharges them in series, thereby achieving voltage doubling output.

[0028] The energy storage capacity of the axial lead high-voltage capacitor 105 should be large and the inherent inductance should be small, and the output voltage amplitude of the DC power supply 101 should not be greater than the withstand voltage amplitude of the axial lead high-voltage capacitor 105 .

[0029] The high-voltage charging resistor 104 and the high-voltage current-limiting resistor 108 have relatively large resistances. It is best to use a water resistor with adjustable resistance made by placing a CuSO4 solution in a flexible plastic tube, with sealed copper or aluminum electrodes at both ends of the plastic tube, so as to achieve a large thermal capacity to meet the electrical insulation strength requirements of the multi-stage Marx topology boost module 1.

[0030] The screw column 103 is vertically spirally fixed on the polytetrafluoroethylene insulating base 107, but does not penetrate the polytetrafluoroethylene insulating base 107, and the screw columns 103 can be axially spirally connected. The screw column 103 is made of metal and also serves to connect the wires and conduct electricity.

[0031] The axial-leaded high-voltage capacitors 105 are easy to install and remove. The number of cascaded capacitors can be designed based on the specific requirements of the boost module. The series discharge of the axial-leaded high-voltage capacitors 105 is achieved through the breakdown conduction of the spherical electrode spark-gap switches 106. Furthermore, there is a fixed correspondence between the two: the number of axial-leaded high-voltage capacitors 105 minus 1 / 2 the number of spherical electrode spark-gap switches 106 equals 1.

[0032] Combine Figure 1 and Figure 3 The three-axis two-cylinder interlocked pulse transmission line includes an external shaft cylinder electrode 12, an intermediate shaft cylinder electrode 13 and an internal solid cylindrical electrode 14. A pulse charging inductor 15 is connected between the external shaft cylinder electrode 12 and the internal solid cylindrical electrode 14 for storing energy. A ring-shaped capacitor voltage divider 16 is embedded in the external shaft cylinder electrode 12. The three-axis two-cylinder interlocked pulse transmission line is filled with dimethyl silicone oil; the three-axis two-cylinder interlocked pulse transmission line is connected to a high-voltage solid-state switch; the pulse charging inductor 15 connects the external shaft cylinder electrode 12 and the internal solid cylindrical electrode 14 to charge the internal solid cylindrical electrode 14; two through holes are provided on the external shaft cylinder electrode 12, one of which is used to fill and discharge dimethyl silicone oil, and the other through hole is used as a channel connecting the high-frequency coaxial connector 27 and the ring-shaped capacitor voltage divider 16. The filling and discharge of dimethyl silicone oil is controlled by the through-hole dimethyl silicone oil flow control valve 28 installed on the through-hole of the external shaft cylinder electrode 12, and before the dimethyl silicone oil is officially introduced, the three-axis two-cylinder interlocking pulse transmission line needs to be tested for liquid tightness.

[0033] After each charge and discharge of the multi-cascade Marx topology boost module 1, there may be residual voltage inside the axial lead high-voltage capacitor 105. However, direct short-circuit discharge of the axial lead high-voltage capacitor 105 is generally not allowed. To ensure the best discharge effect next time and personal safety, a resistor or inductor should be connected in series with a wire to discharge the axial lead high-voltage capacitor 105 after each charge and discharge.

[0034] There is an insulating flange connection plate 9 between the high-voltage solid-state switch outer cylinder 3 and the external shaft cylinder electrode 12. The high-voltage solid-state switch outer cylinder 3, the left side of the external shaft cylinder electrode 12 and the insulating flange connection plate 9 each have four screw holes with the same aperture and are aligned with each other, and are connected and fixed by four metal screw fixings 25.

[0035] A metal flange connector 8 is provided at the center of the insulating flange connection plate 9. The left and right ends of the metal flange connector 8 are respectively spirally connected to the surface flashover high-voltage electrode 7 and the intermediate shaft tube electrode 13 through threads. The right end of the metal flange connector 8 is also closely attached to an internal electrode fixing base 10, and the right end of the internal electrode fixing base 10 is nested and connected with the internal solid cylindrical electrode 14.

[0036] The ring-shaped capacitor voltage divider 16 is connected to a high-precision digital oscilloscope 26 via a high-frequency coaxial connector 27 to monitor the pulse output voltage. Figure 1 and Figure 4The ring-shaped capacitive voltage divider 16 includes a ring-shaped base 1601, a high-conductivity copper tape 1602, and a polyimide tape 1603. The ring-shaped base 1601 is shaped like a hollow cylinder with a groove of a certain depth and width on the outer wall. At least one layer of high-conductivity copper tape 1602 is first fixed on the groove, and then at least one layer of polyimide tape 1603 is wrapped around the outermost layer, thus forming the structure of the ring-shaped capacitive voltage divider 16. The high-conductivity copper tape 1602, the polyimide tape 1603, and the external shaft tube electrode 12 form a capacitor structure. At the same time, the high-conductivity copper tape 1602, the ring-shaped base 1601, and the internal solid cylindrical electrode 14 also form a capacitor structure. The ring-shaped capacitive voltage divider 16 is self-made, and its structural parameters can be adjusted according to demand to change its withstand voltage amplitude, while the cost is also low.

[0037] The left end of the three-axis two-cylinder interlocking pulse transmission line is connected to the high-voltage solid-state switch through a metal flange connector 8, an insulating flange connector plate 9, an internal electrode fixing base 10, four metal screw fixings 25, eight nitrile rubber screw washers 24 and a rubber ring washer 11.

[0038] The metal screw fixing part 25 not only connects and fixes but also plays a conductive role. The function of the nitrile rubber screw washer 24 is to avoid direct contact and wear between the metal screw fixing part 25 and the outer cylinder 3 of the high-voltage solid-state switch and the external shaft cylinder electrode, thereby avoiding reducing the airtightness of the high-voltage solid-state switch air chamber and the three-axis two-cylinder embedded pulse transmission line.

[0039] The metal flange connector 8 is embedded and fixed in the insulating flange connector plate 9. The surface flashover high-voltage electrode 7 is fixedly connected to the metal flange connector 8 by screw threads, and the screw distance is adjustable so that the surface discharge distance is adjustable.

[0040] The intermediate shaft tube electrode 13 is connected to the metal flange connector 8 through a threaded connection, and the spiral distance is adjustable. The left end of the internal solid cylindrical electrode 14 is embedded and fixed in the internal electrode fixing base 10. The internal electrode fixing base 10 is nested in the intermediate shaft tube electrode 13 and the left end is in close contact with the metal flange connector 8.

[0041] The insulating flange connector 18 is arranged between the external shaft cylinder electrode 12 and the VOCs gas discharge shaft cylinder electrode 20. The insulating flange connector 18, the right side of the external shaft cylinder electrode 12 and the left side of the VOCs gas discharge shaft cylinder electrode 20 each have four screw holes with the same aperture and are aligned with each other, and are connected and fixed by four metal screw fixings 25.

[0042] At the corner of the joint between the insulating flange connection plate 9 and the left end of the external shaft tube electrode 12, there is a rubber ring gasket 11 to enhance the airtightness of the three-axis two-tube interlocked pulse transmission line. An annular groove is engraved at the corner of the joint connection between the insulating flange connection plate 9. The depth of the annular groove is approximately 1 / 2 of the diameter of the rubber ring gasket 11. The maximum width of the annular groove is between 4 / 3 and 3 / 2 of the diameter of the rubber ring gasket 11. It is used to place the rubber ring gasket 11. The cross-section of the annular groove is roughly chord-shaped, and the size of the space should leave a certain margin for the extrusion deformation of the rubber ring gasket 11. When the insulating flange connection plate 9 is tightly connected to the external shaft tube electrode 12, the rubber ring gasket 11 is squeezed and deformed, filling the connection gap, thereby enhancing the airtightness of the three-axis two-tube interlocked pulse transmission line.

[0043] There is a rubber ring gasket 11 at the corner where the insulating flange connector 18 and the right end of the external shaft cylinder electrode 12 are connected to increase the airtightness of the three-axis two-cylinder interlocking pulse transmission line.

[0044] The VOCs gas discharge reaction chamber includes a plasma discharge wire electrode 19, a VOCs gas discharge shaft tube electrode 20, a high-voltage electrode clamp 21 and an insulating flange 22. The right end of the VOCs gas discharge reaction chamber is fixedly connected to the insulating flange 22 by four metal screw fixings 25 and eight nitrile rubber screw washers 24. The left and right ends of the plasma discharge wire electrode 19 are respectively connected to the internal solid cylindrical electrode 14 and the high-voltage electrode clamp 21 embedded in the center of the insulating flange 22, so that the plasma discharge wire electrode remains parallel to the VOCs gas discharge shaft tube electrode and is located at the center of the VOCs gas discharge shaft tube electrode.

[0045] The VOCs gas discharge reaction chamber is connected to the three-axis two-cylinder interlocking pulse transmission line through metal screw fixings; one end of the plasma discharge line electrode 19 is fixedly connected to the internal solid cylindrical electrode 14 through a clamp, and the other end of the plasma discharge line electrode 19 is tightly embedded and installed in the center of the insulating flange 22 through the high-voltage electrode clamp 21, so that the plasma discharge line electrode 19 remains parallel to the VOCs gas discharge axis cylinder electrode 20 and is located at the center position of the VOCs gas discharge axis cylinder electrode 20.

[0046] The VOCs gas discharge barrel electrode 20 is provided with two through holes for charging and discharging VOCs waste gas.

[0047] The charging and discharging of VOCs waste gas are controlled by two through-hole VOCs flow control valves 23 installed on the through-holes of the VOCs gas discharge shaft tube electrode 20, and a gas tightness test needs to be performed on the VOCs gas discharge reaction chamber before the VOCs waste gas is formally introduced.

[0048] When the present invention is combined with the pulse discharge device of Marx boost and three-axis two-drum transmission line, plasma pulse discharge is generated by the plasma discharge line electrode 19 and the VOCs gas discharge axis drum electrode 20 to perform discharge treatment on the VOCs waste gas.

[0049] The right end of the three-axis two-cylinder interlocking pulse transmission line is fixedly connected to the left end of the VOCs gas discharge reaction chamber through an insulating flange connector 18, four metal screw fixings 25, eight nitrile rubber screw washers 24 and a rubber ring washer 11. The internal solid cylindrical electrode 14 is connected to the plasma discharge line electrode 19 in the VOCs gas discharge reaction chamber through the insulating flange connector 18. A high-precision current transformer 17 is installed on the outside of the middle of the internal connector. The high-precision current transformer 17 is connected to a high-precision digital oscilloscope 26 to monitor the pulse output current.

[0050] The three-dimensional shapes of the high-voltage solid-state switch outer cylinder 3, surface flashover zero potential electrode 4, dielectric filling electrode 5, surface flashover dielectric 6, surface flashover high-voltage electrode 7, metal flange connector 8, insulating flange connector 9, internal electrode fixing base 10, rubber ring gasket 11, external shaft cylinder electrode 12, intermediate shaft cylinder electrode 13, internal solid cylindrical electrode 14, ring-shaped capacitor voltage divider 16, insulating flange connector 18, VOCs gas discharge shaft cylinder electrode 20, high-voltage electrode clamp 21 and insulating flange 22 are as follows: Figure 1 The position is obtained by rotating 360 degrees around the horizontal center axis of each component, wherein the high-voltage solid-state switch outer cylinder 3 is further punched with two through holes and four screw holes on the central axis plane, the insulating flange connection plate 9 is further punched with a cylindrical groove and four screw holes for placing the multi-cascade Marx topology boost module output electrode 2, the external shaft cylinder electrode 12 is further punched with two through holes on the same edge and four screw holes are punched at its left and right ends, the insulating flange connection piece 18 is further punched with four screw holes, the VOCs gas discharge shaft cylinder electrode 20 is further punched with two through holes on the central axis plane and four screw holes are punched at its left and right ends, the insulating flange plate 22 is further punched with four screw holes, and the positions of the through holes and screw holes are as shown in FIG. Figure 1 and Figure 3 shown.

[0051] The high-voltage solid-state switch outer cylinder 3, surface flashover zero-potential electrode 4, dielectric-filled electrode 5, surface flashover high-voltage electrode 7, metal flange connector 8, external shaft cylinder electrode 12, intermediate shaft cylinder electrode 13, internal solid cylindrical electrode 14, VOCs gas discharge shaft cylinder electrode 20 and high-voltage electrode clamp 21 are made of red copper. Red copper has good conductivity and plasticity, has high transmission efficiency for pulse charging energy, and can be processed into various shapes according to needs.

[0052] The surface flashover dielectric 6, insulating flange connection plate 9, internal electrode fixing base 10, annular base 1601, insulating flange connection 18, and insulating flange plate 22 are made of polytetrafluoroethylene (PTFE). PTFE exhibits excellent chemical stability, corrosion resistance, sealing properties, electrical insulation, and aging resistance. Components fabricated from PTFE exhibit excellent stability during device operation and can enhance the sealing of the high-voltage solid-state switch chamber, the three-axis, two-tube interlocked pulse transmission line, and the VOCs gas discharge reaction chamber. It is worth noting that the material of the surface flashover dielectric 6 is not limited to the PTFE mentioned in this invention; other insulating materials such as soda lime, quartz glass, Teflon, and ceramics can be selected based on discharge requirements and conditions.

[0053] The material of the plasma discharge wire electrode is tungsten wire with a diameter of 0.1 mm.

[0054] Regulation Figure 1 The maximum horizontal length of each component is the height, the maximum vertical length is the maximum diameter, the external length of the vertical shaft tube is the outer wall diameter, and the internal length of the vertical shaft tube is the inner wall diameter. The unit is millimeters (mm). When the outer wall diameter and the maximum diameter are the same, only the maximum diameter is indicated. The dimensions of some components are shown in Table 1.

[0055] Table 1

[0056]

[0057] The working principle of the pulse discharge device combining Marx boost and three-axis two-tube transmission line is as follows: Figure 2 The operating principle of the multi-cascade Marx topology boost module 1 can be simply described as parallel charging and series discharge of capacitors. Assuming the output voltage of DC power supply 101 is V0, n axial-leaded high-voltage capacitors 105 (two in the figure) are connected in parallel and charged to V0 through high-voltage charging resistors 104. Typically, the first pair of spherical electrode spark-gap switches 106 breaks down first, followed by the remaining spherical electrode spark-gap switches 106 due to the overvoltage across the discharge gap. At this point, the n axial-leaded high-voltage capacitors 105 are connected in series through the broken-down 2(n-1) spherical electrode spark-gap switches, generating a voltage with an amplitude of nV0 across the last two vertical screw studs 103. This generates a high-voltage pulse across the connected load, namely the high-voltage solid-state switch. High-voltage current-limiting resistors 108 protect DC power supply 101 during the discharge of the axial-leaded high-voltage capacitors 105.

[0058] Combine Figure 1Before charging the multi-cascade Marx topology boost module 1, SF6 gas, dimethyl silicone oil and VOCs exhaust gas are introduced into the high-voltage solid-state switch gas chamber, the three-axis two-cylinder interlocking pulse transmission line and the VOCs gas discharge reaction chamber by controlling the through-hole SF6 flow control valve 23, the through-hole dimethyl silicone oil flow control valve 28 and the through-hole VOCs flow control valve 29 respectively.

[0059] (1) When the multi-stage Marx topology boost module 1 is connected to the multi-stage Marx topology boost module output electrode 2 and the high-voltage solid-state switch outer cylinder 3 and starts to charge, the intermediate shaft cylinder electrode 13 is charged first, and at the same time, the surface discharge has not yet occurred, that is, the high-voltage solid-state switch is in the off state, and the outer shaft cylinder electrode 12 is grounded through the conductive connection metal screw fixing part 25 and the indirect conductive connection high-voltage solid-state switch outer cylinder 3, and the intermediate shaft cylinder electrode 13 and the outer shaft cylinder electrode 12 form a single transmission line.

[0060] (2) When the potential difference between the surface flashover high-voltage electrode 7 and the surface flashover zero-potential electrode 4 reaches the surface discharge voltage of the surface flashover dielectric 6, surface discharge occurs, the high-voltage solid-state switch is in the on state, and an initial pulse is generated. The multi-cascade Marx topology boost module 1 begins to charge the external shaft cylinder electrode 12 through the high-voltage solid-state switch outer cylinder 3 and the metal screw fixing 25, and the external shaft cylinder electrode 12 and the internal solid cylindrical electrode 14 are connected to a pulse charging inductor 15 for charging the internal solid cylindrical electrode 14. After the internal solid cylindrical electrode 14 is charged, it also forms a single transmission line with the intermediate shaft cylinder electrode 13.

[0061] (3) After the external cylindrical electrode 12, the intermediate cylindrical electrode 13 and the internal solid cylindrical electrode 14 are charged, the two single transmission lines formed between them pass through Figure 1 The combination of the middle space forms a dual transmission structure, that is, a three-axis two-cylinder interlocking pulse transmission line, which can output 100% of the charging pulse voltage amplitude under ideal conditions. The pulse duration of the output pulse of the three-axis two-cylinder interlocking pulse transmission line is T It can be calculated by the following formula:

[0062] (1);

[0063] (2);

[0064] in, v is the transmission speed of electromagnetic waves in dimethyl silicone oil, and are the relative dielectric constant and relative magnetic permeability of dimethyl silicone oil, c is the propagation speed of electromagnetic waves in vacuum, Lis the length of the intermediate shaft electrode 13. The dimethyl silicone oil used in this device is PMX-200 with a viscosity of 350 cs, and its relative dielectric constant and relative magnetic permeability are 2.75 and 1 respectively. L It is 530mm, which can be obtained under ideal conditions. T The value is about 5.86ns.

[0065] (4) Finally, the plasma discharge wire electrode 19 connected to the inner solid cylindrical electrode 14 and the VOCs gas discharge shaft cylinder electrode 20 connected to the outer shaft cylinder electrode 12 through the metal screw fixing member 25 perform plasma pulse discharge treatment on the VOCs exhaust gas in the VOCs gas discharge reaction chamber.

Claims

1. A pulse discharge device combining Marx boost and three-axis two-tube transmission line, characterized by: It includes a multi-stage cascade Marx topology boost module (1) connected in sequence, a high-voltage solid-state switch, a three-axis two-tube interlocking pulse transmission line and a VOCs gas discharge reaction chamber; The high-voltage solid-state switch comprises an insulating flange connection plate (9), the insulating flange connection plate (9) being connected to a multi-stage Marx topology boost module output electrode (2) via a metal flange connection piece (8), the multi-stage Marx topology boost module output electrode (2) being connected to the multi-stage Marx topology boost module (1), one side of the insulating flange connection plate (9) being connected to a three-axis two-tube interlocking pulse transmission line, the other side of the insulating flange connection plate (9) being connected to a high-voltage solid-state switch outer tube (3), a surface flashover zero potential electrode (4) being coaxially arranged at the center of the high-voltage solid-state switch outer tube (3), the surface flashover zero potential electrode (4) being coaxially connected to a surface flashover dielectric (6) and a surface flashover high-voltage electrode (7) in sequence, the surface flashover high-voltage electrode (7) being connected to the metal flange connection piece (8), and a dielectric filling electrode (5) being embedded in the surface flashover dielectric (6).

2. The pulse discharge device combining Marx boost and three-axis two-tube transmission line according to claim 1 is characterized in that: The multi-stage Marx topology boost module (1) comprises a polytetrafluoroethylene insulation base (107), two rows of screw columns (103) are arranged on the polytetrafluoroethylene insulation base (107), a row of axial lead type high voltage capacitors (105) arranged in parallel is arranged between the two rows of screw columns (103), and the series discharge of the axial lead type high voltage capacitors (105) is achieved by the breakdown conduction of the ball electrode spark gap switch (106) between two adjacent parallel axial lead type high voltage capacitors (105); In each row of screw columns (103), high-voltage charging resistors (104) and high-voltage current-limiting resistors (108) are alternately arranged between two adjacent screw columns (103); the two rows of screw columns (103) are respectively connected to a DC power supply (101) via wires (102).

3. The pulse discharge device combining Marx boost and three-axis two-tube transmission line according to claim 2, characterized in that: The number of the axial lead type high voltage capacitors (105) minus 1 / 2 of the number of the ball electrode spark gap switches (106) equals 1.

4. The pulse discharge device combining Marx boost and three-axis two-tube transmission line according to claim 3 is characterized in that: The three-axis two-tube interlocking pulse transmission line comprises an internal solid cylindrical electrode (14) coaxially connected to the center of an insulating flange connection plate (9), an intermediate shaft tube electrode (13) and an external shaft tube electrode (12) are coaxially arranged outside the internal solid cylindrical electrode (14), a pulse charging inductor (15) is connected between the internal solid cylindrical electrode (14) and the external shaft tube electrode (12), a ring-shaped capacitor voltage divider (16) is embedded inside the external shaft tube electrode (12), and a high-frequency coaxial connector (27) is connected to the ring-shaped capacitor voltage divider (16).

5. The pulse discharge device combining Marx boost and three-axis two-tube transmission line according to claim 4 is characterized in that: The ring-shaped capacitive voltage divider (16) comprises a ring-shaped base (1601), a high-conductivity copper tape (1602) and a polyimide tape (1603) which are coaxially arranged in sequence from the inside to the outside. The high-conductivity copper tape (1602), the polyimide tape (1603) and the external cylindrical electrode (12) form a capacitor structure; the high-conductivity copper tape (1602), the ring-shaped base (1601) and the internal solid cylindrical electrode (14) form another capacitor structure.

6. The pulse discharge device combining Marx boost and three-axis two-tube transmission line according to claim 5, characterized in that: The VOCs gas discharge reaction chamber includes a VOCs gas discharge shaft tube electrode (20) coaxially arranged with an internal solid cylindrical electrode (14), a plasma discharge wire electrode (19) coaxially arranged at the center of the VOCs gas discharge shaft tube electrode (20), one end of the plasma discharge wire electrode (19) is connected to the internal solid cylindrical electrode (14), and the other end of the plasma discharge wire electrode (19) is connected to a high-voltage electrode clamp (21), and the high-voltage electrode clamp (21) is installed at the center of an insulating flange (22), and the insulating flange (22) is connected to one end of the VOCs gas discharge shaft tube electrode (20), and the other end of the VOCs gas discharge shaft tube electrode (20) is connected to the external shaft tube electrode (12) through an insulating flange connector (18), and the internal solid cylindrical electrode (14) passes through the insulating flange connector (18) to be connected to the plasma discharge wire electrode (19), and a high-precision current transformer (17) is installed at the connection between the internal solid cylindrical electrode (14) and the insulating flange connector (18).

7. The pulse discharge device combining Marx boost and three-axis two-tube transmission line according to claim 6, characterized in that: The high-precision current transformer (17) and the high-frequency coaxial connector (27) are both connected to a high-precision digital oscilloscope (26).

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