High-voltage nanosecond pulse coaxial line capable of realizing cable connection between inner cylinder and outer cylinder

Abstract

The invention provides the high-voltage nanosecond pulse coaxial line capable of realizing cable connection between the inner cylinder and the outer cylinder, and the problems that the cable connection mode between the inner cylinder and the outer cylinder of the existing coaxial line cannot meet the requirement of introduction of various types of signals, the anti-interference capability is weak, and the reliability is poor can be solved. The coaxial line comprises an outer cylinder, an inner cylinder, an insulation supporting body, a vortex-shaped hollow inductor and a multi-core cable arranged in the vortex-shaped hollow inductor in a penetrating mode, the insulation supporting body is arranged on the outer side of the inner cylinder in a sleeving mode and located between the outer cylinder and the inner cylinder, the vortex-shaped hollow inductor is arranged on the outer wall of the insulation supporting body, the two ends of the vortex-shaped hollow inductor are arranged on the outer cylinder and the inner cylinder in a penetrating mode respectively and connected with the outer cylinder and the inner cylinder in a sealed mode, and the multi-core cable is arranged in the vortex-shaped hollow inductor. The outer diameter dL of the vortex-shaped air core inductor, the inner diameter a of the outer cylinder and the outer diameter b of the inner cylinder meet the following relation: (a-b) / [N * (dL + d)] > = sin theta, d is 0.5-2 times of dL, the inter-turn average electric field E is lower than the direct-current breakdown field strength of a medium between the outer cylinder and the inner cylinder, and the corresponding inductive reactance value # imgabs0 # of the vortex-shaped air core inductor under nanosecond pulse

Description

Technical Field

[0001] The invention relates to a high-voltage nanosecond pulse coaxial line, in particular to a high-voltage nanosecond pulse coaxial line capable of realizing cable connection between inner and outer cylinders. Background Art

[0002] In pulse power technology, in order to transmit pulse voltage or current with high power capacity, pulse drive sources, transmission lines, etc. usually adopt coaxial cable structures to generate nanosecond-level, high-voltage pulses of more than 100 kilovolts between the inner and outer cylinders of the coaxial cable. With the development of technologies such as gas switches and high-power microwaves, there are scenarios where it is necessary to lay cables between the inner and outer cylinders of nanosecond pulse coaxial cables, such as the power supply and control of the main switch trigger of the built-in pulse drive source, the optical signal transmission of the omnidirectional rotating antenna signal acquisition device, etc., which require the laying of multiple types of cables such as power cables, signal cables, and optical fibers. Since a transient strong electromagnetic field will be generated between the inner and outer cylinders when the coaxial cable transmits high-voltage nanosecond pulses, when laying cables, it is necessary to avoid insulation failure between the inner and outer cylinders of the coaxial cable, avoid introducing transient strong electromagnetic fields into cable interference equipment, and avoid attenuation of nanosecond pulses.

[0003] There are three main cable connection methods between the inner and outer cylinders of the existing high-voltage nanosecond pulse coaxial line: (1) Winding a conical spiral inductor with an insulated metal wire between the inner and outer cylinders of the coaxial line to achieve grounding or voltage boosting of the inner cylinder; (2) Using a special high-voltage cable and an insulating sealing structure to introduce the electrical signal from the outer cylinder into the inner cylinder; (3) Setting a coil on the inner cylinder and coupling with the primary coil on the outer cylinder through a magnetic field to achieve voltage boosting of the trigger device in the inner cylinder. However, the common problems of the above-mentioned cable connection methods between the inner and outer cylinders of the high-voltage nanosecond pulse coaxial line are: they cannot meet the requirements of introducing multiple types of signals, have weak anti-interference capabilities, and have poor reliability. Summary of the invention

[0004] The purpose of the present invention is to solve the technical problems that the existing cable connection method between the inner and outer cylinders of the high-voltage nanosecond pulse coaxial line cannot meet the needs of introducing various types of signals, has weak anti-interference ability and poor reliability, and to provide a high-voltage nanosecond pulse coaxial line that can realize cable connection between the inner and outer cylinders.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] A high-voltage nanosecond pulse coaxial line that can realize cable connection between inner and outer tubes. Its special features are:

[0007] It includes an outer cylinder, an inner cylinder, an insulating support, a vortex hollow inductor and a multi-core cable;

[0008] The insulating support body is a hollow truncated cone structure, and the insulating support body is sleeved on the outside of the inner cylinder and is located between the outer cylinder and the inner cylinder;

[0009] The vortex hollow inductor is formed by winding a metal round tube in a vortex line. The vortex hollow inductor is arranged on the outer wall of the insulating support body. The two ends of the vortex hollow inductor are respectively penetrated on the outer tube and the inner tube, and are sealed and connected with the outer tube and the inner tube. The outer diameter d of the vortex hollow inductor is L The inner diameter a of the outer tube and the outer diameter b of the inner tube satisfy the following relationship: (ab) / [N×(d L +d)]≥sinθ, where N is the total number of turns of the vortex hollow inductor, d is the distance between the turns of the vortex hollow inductor, and θ is the angle between the inner wall of the insulating support and the inner cylinder; the distance between the turns d of the vortex hollow inductor is its outer diameter d L The average electric field E between turns is lower than the DC breakdown field strength of the medium between the outer tube and the inner tube; the inductive reactance value corresponding to the vortex hollow inductor under nanosecond pulse is Among them, ε r2 is the relative dielectric constant of the medium between the outer cylinder and the inner cylinder;

[0010] The multi-core cable is inserted into the spiral hollow inductor and insulated from the spiral hollow inductor. One end of the multi-core cable close to the outer tube is connected to a device for power supply and signal control, and the other end close to the inner tube is connected to a device for switch triggering and signal monitoring.

[0011] Furthermore, a first base is provided on the outer wall of the outer cylinder;

[0012] A second base is provided on the inner wall of the inner cylinder;

[0013] The two ends of the vortex hollow inductor are respectively penetrated on the first base and the second base; the first base and the second base are both installed with sealing components for sealing the medium between the inner cylinder and the outer cylinder, and achieving good electrical contact between the vortex hollow inductor and the inner cylinder and the outer cylinder.

[0014] Further, the sealing assembly includes a spin-on sealing cover and a sealing gasket;

[0015] The two spin-on sealing covers are both sleeved on the outside of the vortex-shaped hollow inductor and are respectively threadedly connected to the first base and the second base;

[0016] The two sealing gaskets are both sleeved on the outside of the vortex hollow inductor and are respectively arranged between the spin-on sealing cover and the end of the first base, and between the spin-on sealing cover and the end of the second base.

[0017] Furthermore, in order to improve reliability, the surface roughness of the outer surface of the vortex-shaped hollow inductor is Ra≤6.3.

[0018] Furthermore, a vortex-shaped semi-cylindrical groove is provided on the outer wall of the insulating support body along the axial direction; the vortex-shaped hollow inductor is arranged in the semi-cylindrical groove;

[0019] The relative dielectric constant ε of the insulating support r1 The relative dielectric constant ε of the medium between the outer cylinder and the inner cylinder r2 The following relationship should be satisfied: r1 -ε r2 | / ε r2 ≤0.5, thereby reducing the electric field in the coaxial line medium at the semi-cylindrical groove.

[0020] Furthermore, in order to further improve the installation stability of the vortex hollow inductor and the insulating support, the groove width of the semi-cylindrical groove is adapted to the outer diameter of the vortex hollow inductor, and the groove depth of the semi-cylindrical groove is not less than 1 / 2 of the outer diameter of the vortex hollow inductor;

[0021] The inner diameter of the small end of the insulating support body is matched with the outer diameter of the inner cylinder, and the outer diameter of the large end of the insulating support body is matched with the inner diameter of the outer cylinder.

[0022] Furthermore, the wall thickness h of the vortex-shaped air-core inductor and the outer diameter d of the vortex-shaped air-core inductor are L And the outer diameter d of the multi-core cable s The following relationship is satisfied: 2h+d s <d L .

[0023] Furthermore, the multi-core cable includes a two-core DC power cable and a two-core trigger control cable, and the two-core DC power cable and the two-core trigger control cable are respectively connected to devices for power supply and signal control at one end close to the outer tube, and are respectively connected to devices for switch triggering and signal monitoring at one end close to the inner tube.

[0024] Furthermore, the spin-on sealing cover and the sealing gasket are both made of metal.

[0025] Furthermore, the first base is integrally formed with the outer tube, or the first base is welded to the outer wall of the outer tube;

[0026] The second base is formed integrally with the inner tube, or the second base is welded to the inner wall of the inner tube.

[0027] Beneficial effects of the present invention:

[0028] 1. The present invention provides a high-voltage nanosecond pulse coaxial line that can realize cable connection between inner and outer cylinders, wherein a vortex hollow inductor is provided, and a multi-core cable is inserted into the vortex hollow inductor, thereby realizing the connection between the outside of the coaxial line and multiple types of cables in the inner cylinder, thereby meeting the demand for introducing multiple types of signals from the outside to the inner cylinder, and improving the flexibility of the layout of the triggering, control, signal acquisition and other devices of the pulse power system.

[0029] 2. The present invention adopts a vortex hollow inductor to achieve high-resistance isolation between the inner and outer cylinders under nanosecond pulses. The cable is sealed between the inner and outer cylinders with a vortex hollow inductor, which can completely shield the interference of high-voltage nanosecond pulses on the internal cables and has strong anti-interference ability.

[0030] 3. The present invention does not affect the transmission of nanosecond pulses in the coaxial line by reasonably designing the inductive reactance value. By controlling the turn-to-turn distance and the average electric field between turns of the vortex hollow inductor, the introduction of the structure will not cause turn-to-turn breakdown and insulation failure between the inner and outer cylinders, thereby ensuring reliable insulation under high-voltage nanosecond pulses.

[0031] 4. The present invention has the advantages of high-voltage resistance and a simple and reliable sealing structure. The surface roughness of the outer surface of the vortex hollow inductor in the present invention is Ra≤6.3, which can avoid local electric field enhancement under high voltage, thereby improving reliability. In addition, the relative dielectric constant of the insulating support is similar to the relative dielectric constant of the medium between the outer cylinder and the inner cylinder, which can reduce the electric field in the coaxial line medium at the semi-cylindrical groove. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a three-dimensional structural schematic diagram of an embodiment of a high-voltage nanosecond pulse coaxial line that can realize cable connection between inner and outer cylinders of the present invention;

[0033] Figure 2 yes Figure 1 B-direction view;

[0034] Figure 3 yes Figure 2 AA section view;

[0035] Figure 4 yes Figure 3 A partial enlarged view of point I in the middle;

[0036] Figure 5 yes Figure 3 A partial enlarged view of position II in the middle;

[0037] Figure 6 is the voltage waveform of the nanosecond pulse transmitted by the embodiment of the present invention before and after passing through the vortex air-core inductor;

[0038] Figure 7It is the trigger signal waveform before and after entering the vortex hollow inductor during the transmission of the high-voltage nanosecond pulse in the embodiment of the present invention;

[0039] Figure 8 It is the DC voltage waveform before and after entering the vortex hollow inductor during high-voltage nanosecond pulse transmission in the embodiment of the present invention.

[0040] Description of reference numerals:

[0041] 1-spin-on sealing cover, 2-vortex hollow inductor, 3-multi-core cable, 31-dual-core DC power cord, 32-dual-core trigger control line, 4-insulating support body, 41-semi-cylindrical groove, 5-outer cylinder, 51-first base, 6-inner cylinder, 61-second base, 7-sealing assembly, 8-sealing gasket. DETAILED DESCRIPTION

[0042] like Figure 1-Figure 5 As shown, a high-voltage nanosecond pulse coaxial line that can realize cable connection between inner and outer cylinders includes an outer cylinder 5, an inner cylinder 6, an insulating support body 4, a vortex hollow inductor 2, and a multi-core cable 3. Specifically, a first base 51 is welded on the outer wall of the outer cylinder 5, and a second base 61 is welded on the inner wall of the inner cylinder 6. In other embodiments, the first base 51 is integrally formed with the outer cylinder 5, and the second base 61 is integrally formed with the inner cylinder 6. The insulating support body 4 is a hollow truncated cone structure, which is sleeved on the outside of the inner cylinder 6 and located between the outer cylinder 5 and the inner cylinder 6. The inner diameter of the small end of the insulating support body 4 is adapted to the outer diameter of the inner cylinder 6, and the outer diameter of the large end of the insulating support body 4 is adapted to the inner diameter of the outer cylinder 5. A vortex-shaped semi-cylindrical groove 41 is provided on the outer wall of the insulating support body 4 along the axial direction. The vortex-shaped hollow inductor 2 is formed by winding a round copper tube in a vortex-shaped line. The vortex-shaped hollow inductor 2 is arranged in the semi-cylindrical groove 41. The groove width of the semi-cylindrical groove 41 is adapted to the outer diameter of the vortex-shaped hollow inductor 2. The groove depth of the semi-cylindrical groove 41 is not less than 1 / 2 of the outer diameter of the vortex-shaped hollow inductor 2. The two ends of the vortex-shaped hollow inductor 2 are respectively penetrated on the first base 51 and the second base 61. The first base 51 and the second base 61 are both installed with sealing components 7. Each sealing component 7 includes a spiral The press-fit sealing cover 1 and the sealing gasket 8 are made of metal. The two press-fit sealing covers 1 are sleeved on the outside of the vortex hollow inductor 2 and are respectively threadedly connected to the first base 51 and the second base 61. The two sealing gaskets 8 are sleeved on the outside of the vortex hollow inductor 2 and are respectively arranged between the end of the press-fit sealing cover 1 and the first base 51 and the end of the press-fit sealing cover 1 and the second base 61 to achieve sealing of the medium between the inner cylinder 6 and the outer cylinder 5, and to achieve good electrical contact between the vortex hollow inductor 2 and the inner cylinder 6 and the outer cylinder 5. The surface roughness of the outer surface of the vortex hollow inductor 2 is Ra=6.3. The outer diameter d of the vortex hollow inductor 2 LThe inner diameter a of the outer tube 5 and the outer diameter b of the inner tube 6 satisfy the following relationship: (ab) / [N×(d L +d)]≥sinθ, where N is the total number of turns of the vortex hollow inductor 2, d is the distance between the turns of the vortex hollow inductor 2, and θ is the angle between the inner wall of the insulating support 4 and the inner cylinder 6. The distance between the turns d of the vortex hollow inductor 2 is the outer diameter d L The average electric field E between turns is lower than the DC breakdown field strength of the medium between the outer cylinder 5 and the inner cylinder 6, E = U / (N×d), where U is the pulse peak voltage. The inductive reactance value corresponding to the vortex hollow inductor 2 under nanosecond pulse Among them, ε r2 is the relative dielectric constant of the medium between the outer tube 5 and the inner tube 6. The relative dielectric constant ε of the insulating support 4 r1 The relative dielectric constant ε of the medium between the outer cylinder 5 and the inner cylinder 6 r2 The following relationship should be satisfied: r1 -ε r2 | / ε r2 ≤0.5.

[0043] The multi-core cable 3 is inserted into the vortex hollow inductor 2, and its outer diameter is smaller than the inner diameter of the vortex hollow inductor 2. The outer skin of the multi-core cable 3 is insulated from the vortex hollow inductor 2. L and the outer diameter d of the multi-core cable 3 s The following relationship is satisfied: 2h+d s <d L The multi-core cable 3 in this embodiment includes a 700V dual-core DC power line 31 and a dual-core trigger control line 32. The ends of the 700V dual-core DC power line 31 and the dual-core trigger control line 32 close to the outer tube 5 are respectively connected to devices for power supply and signal control, and the ends close to the inner tube 6 are respectively connected to devices for switch triggering and signal monitoring.

[0044] In this embodiment, the impedance of the coaxial line The coaxial line is used to transmit a pulse with a voltage of 400 kV and a pulse width of 20 ns. The inner diameter a of the outer cylinder 5 is 280 mm, the outer diameter b of the inner cylinder 6 is 90 mm, the medium is No. 45 transformer oil, and the relative dielectric constant ε r2 is 2.3, the material of the insulating support 4 is MC nylon, and the relative dielectric constant ε r1 The outer diameter d of the vortex hollow inductor 2 is 3.2, the depth of the semi-cylindrical groove 41 of the insulating support 4 is 4 mm, and the groove spacing is the same as the turn-to-turn distance. LThe wall thickness h is 7mm, the total number of turns N is 10, the distance between turns d is 6mm, and the angle θ between the inner wall of the insulating support 4 and the inner tube 6 is 40°. According to the inductance formula, the inductance value of the vortex hollow inductor 2 is about 30μH. Under the action of a pulse with a pulse width of 20ns, the inductive reactance value X of the vortex hollow inductor 2 is L It is about 4.7kΩ, which is about 105 times the impedance of the 45Ω coaxial line. The average electric field E between turns is 67kV / cm, which is less than the DC breakdown field strength of No. 45 transformer oil.

[0045] Figure 6 3 is the voltage waveform of the nanosecond pulse transmitted in this embodiment before and after passing through the vortex-shaped air-core inductor 2. It can be seen from the figure that the pulse waveform before and after passing through the vortex-shaped air-core inductor 2 remains consistent, and the vortex-shaped air-core inductor 2 does not affect the transmission of the nanosecond pulse.

[0046] Figure 7 is the trigger signal waveform before and after the high-voltage nanosecond pulse enters the vortex hollow inductor 2 during transmission in this embodiment, Figure 8 is the DC voltage waveform before and after the high-voltage nanosecond pulse enters the vortex-shaped air-core inductor 2 during transmission in this embodiment, Figure 7 and Figure 8 It can be seen that the vortex hollow inductor 2 realizes the transmission of two electrical signals, namely, trigger and DC voltage, between the inner cylinder 6 and the outer cylinder 5, and these two electrical signals are not interfered by the high-voltage nanosecond pulse in the coaxial line.

[0047] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A high-voltage nanosecond pulse coaxial line capable of realizing cable connection between inner and outer tubes, characterized in that: It comprises an outer cylinder (5), an inner cylinder (6), an insulating support body (4), a vortex hollow inductor (2) and a multi-core cable (3); The insulating support body (4) is a hollow truncated cone-shaped structure, and the insulating support body (4) is sleeved on the outside of the inner cylinder (6) and is located between the outer cylinder (5) and the inner cylinder (6); The vortex hollow inductor (2) is formed by winding a metal round tube in a spiral line. The vortex hollow inductor (2) is arranged on the outer wall of the insulating support (4). The two ends of the vortex hollow inductor (2) are respectively passed through the outer tube (5) and the inner tube (6), and are sealed and connected to the outer tube (5) and the inner tube (6). The outer diameter d of the vortex hollow inductor (2) is L , the inner diameter a of the outer tube (5) and the outer diameter b of the inner tube (6) satisfy the following relationship: (ab) / [N×(d L +d)]≥sinθ, wherein N is the total number of turns of the vortex hollow inductor (2), d is the distance between the turns of the vortex hollow inductor (2), and θ is the angle between the inner wall surface of the insulating support (4) and the inner cylinder (6); the distance between the turns d of the vortex hollow inductor (2) is equal to its outer diameter d L The average electric field E between turns is lower than the DC breakdown field strength of the medium between the outer cylinder (5) and the inner cylinder (6); the inductive reactance value corresponding to the vortex hollow inductor (2) under nanosecond pulse is Among them, ε r2 is the relative dielectric constant of the medium between the outer cylinder (5) and the inner cylinder (6); The multi-core cable (3) is inserted into the spiral hollow inductor (2) and is insulated from the spiral hollow inductor (2). The end of the multi-core cable (3) close to the outer tube (5) is externally connected to a device for power supply and signal control, and the end of the multi-core cable (3) close to the inner tube (6) is externally connected to a device for switch triggering and signal monitoring.

2. The high-voltage nanosecond pulse coaxial line capable of realizing cable connection between inner and outer cylinders according to claim 1, characterized in that: A first base (51) is provided on the outer wall of the outer cylinder (5); A second base (61) is provided on the inner wall of the inner cylinder (6); The two ends of the vortex-shaped hollow inductor (2) are respectively inserted into the first base (51) and the second base (61); the first base (51) and the second base (61) are both provided with sealing components (7) for sealing the medium between the inner cylinder (6) and the outer cylinder (5), and for achieving good electrical contact between the vortex-shaped hollow inductor (2) and the inner cylinder (6) and the outer cylinder (5).

3. The high-voltage nanosecond pulse coaxial line capable of realizing cable connection between inner and outer cylinders according to claim 2, characterized in that: The sealing assembly (7) comprises a spin-on sealing cover (1) and a sealing gasket (8); The two spin-on sealing covers (1) are both sleeved on the outside of the vortex-shaped hollow inductor (2) and are respectively threadedly connected to the first base (51) and the second base (61); The two sealing gaskets (8) are both sleeved on the outside of the spiral hollow inductor (2), and are respectively arranged between the end of the spun sealing cover (1) and the first base (51), and between the end of the spun sealing cover (1) and the second base (61).

4. The high-voltage nanosecond pulse coaxial line capable of realizing cable connection between inner and outer cylinders according to claim 1, 2 or 3, characterized in that: The surface roughness of the outer surface of the vortex hollow inductor (2) is Ra≤6.

3.

5. The high-voltage nanosecond pulse coaxial line capable of realizing cable connection between inner and outer cylinders according to claim 4, characterized in that: A vortex-shaped semi-cylindrical groove (41) is provided on the outer wall of the insulating support body (4) along the axial direction; the vortex-shaped hollow inductor (2) is arranged in the semi-cylindrical groove (41); The relative dielectric constant ε of the insulating support (4) is r1 The relative dielectric constant ε of the medium between the outer cylinder (5) and the inner cylinder (6) r2 The following relationship should be satisfied: r1 -ε r2 | / ε r2 ≤0.

5.

6. The high-voltage nanosecond pulse coaxial line capable of realizing cable connection between inner and outer cylinders according to claim 5, characterized in that: The groove width of the semi-cylindrical groove (41) is adapted to the outer diameter of the vortex-shaped hollow inductor (2), and the groove depth of the semi-cylindrical groove (41) is not less than 1 / 2 of the outer diameter of the vortex-shaped hollow inductor (2); The inner diameter of the small end of the insulating support body (4) is matched with the outer diameter of the inner tube (6), and the outer diameter of the large end of the insulating support body (4) is matched with the inner diameter of the outer tube (5).

7. The high-voltage nanosecond pulse coaxial line capable of realizing cable connection between inner and outer cylinders according to claim 6, characterized in that: The wall thickness h of the vortex-shaped hollow inductor (2) and the outer diameter d of the vortex-shaped hollow inductor (2) are L and the outer diameter d of the multi-core cable (3) s The following relationship is satisfied: 2h+d s <d L .

8. The high-voltage nanosecond pulse coaxial line capable of realizing cable connection between inner and outer cylinders according to claim 7, characterized in that: The multi-core cable (3) comprises a double-core DC power line (31) and a double-core trigger control line (32); the double-core DC power line (31) and the double-core trigger control line (32) are respectively connected to devices for power supply and signal control at one end close to the outer tube (5), and are respectively connected to devices for switch triggering and signal monitoring at one end close to the inner tube (6).

9. The high-voltage nanosecond pulse coaxial line capable of realizing cable connection between inner and outer cylinders according to claim 3, characterized in that: The spin-on sealing cover (1) and the sealing gasket (8) are both made of metal.

10. The high-voltage nanosecond pulse coaxial line capable of realizing cable connection between inner and outer cylinders according to claim 9, characterized in that: The first base (51) is integrally formed with the outer tube (5), or the first base (51) is welded to the outer wall of the outer tube (5); The second base (61) is integrally formed with the inner tube (6), or the second base (61) is welded to the inner wall of the inner tube (6).

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