CN109787589B - Nanosecond composite shock wave generator based on vacuum sealed environment - Google Patents

Abstract

The invention discloses a nanosecond composite shock wave generating device based on a vacuum closed environment, which comprises a vacuum closed cavity body, wherein the vacuum closed cavity body is composed of an upper insulating flange, a lower metal flange and an insulating pipe, the air pressure of the vacuum closed cavity body is far lower than the standard air pressure, and an energy storage capacitor, a discharge switch and resistors formed in various shapes are all arranged in the vacuum closed environment, so that on one hand, each element has good insulating and pressure-resistant characteristics, on the other hand, the gap distance of the discharge switch can be further reduced, and because discharge is carried out in the same closed vacuum environment, each element in a nanosecond generating loop can be compactly arranged and a connecting line can be shortened, the increase of the total inductance of the loop caused by the connecting line is further shortened, the connecting line inductance of the loop can be reduced.

Description

Nanosecond composite shock wave generator based on vacuum sealed environment

technical field

The invention belongs to a nanosecond pulse current generating device, in particular to a nanosecond composite shock wave generating device based on a vacuum-sealed environment.

Background technique

With the development of pulse current technology, pulse current with nanosecond rise time and microsecond long duration has become a research hotspot. Research in this field in the United States and Russia is at an advanced level. Well-known pulse technology laboratories in the United States include National Lawrence Livermore Laboratory, Sandia National Laboratory, Maxwell Laboratory, Los Alamos Laboratory, Naval Weapons Research Center, University of Texas, etc. The Hermes-I pulse device was built in the United States in 1967; the Aurora device was built in the United States in 1972. The pulse experimental equipment consists of four Marx generators, which is of great significance in the history of development. Russia's famous pulse technology laboratories include Kurchatov Institute, Novosibirsk Institute of Nuclear Physics, Tomsk Institute of Large Current Electronics, Institute of Electrophysics Equipment, and Lebedev Institute. In 1985, Russia successfully developed pulse generators such as AHrapa-5.

In my country, research on pulse current technology began in the 1970s. There are many scientific research institutions in my country engaged in research in this field. Famous scientific research institutions include Institute of Plasma Physics, Chinese Academy of Sciences, Institute of High Energy Physics, Chinese Academy of Sciences, Institute of Electrical Technology, Chinese Academy of Sciences, Tsinghua University, Huazhong University of Science and Technology, Xi'an Jiaotong University, Northwest Nuclear Technology Research Wait.

The duration of the pulsed current wave is generally in the nanosecond to microsecond level. The lightning phenomenon that occurs in the atmosphere has a great impact on human life. The current wave of the subsequent short-term lightning strike in lightning protection has an approximate peak time of T ₁ ≈ 250ns and a long wave tail duration. This waveform has a short rise time. , and longer duration. For the short-pulse composite shock wave in the electromagnetic environment test method, the peak time of the voltage and current shock waves is 100ns, and the half-peak time is about 2.5μs.

The nanosecond shock wave is generally generated by the RLC second-order circuit. The loop inductance is a crucial factor that affects the rise time of the pulse current and the loop efficiency. The total inductance of the RLC second-order circuit includes the residual inductance of the energy storage capacitor C and the residual of the waveform forming resistance. Inductance, residual inductance of discharge switch and loop connection inductance, etc., plus composite shock wave not only has requirements for the waveform parameters of voltage and current, but also puts forward certain requirements for the ratio of voltage peak to current peak. How to reduce the occurrence of shock waves The equivalent inductance of the loop is the key technology of nanosecond composite shock wave generation.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a nanosecond composite shock wave generating device based on a vacuum closed environment, which can reduce the total inductance of the loop and efficiently generate nanosecond composite shock waves.

For achieving the above object, the present invention adopts the following scheme:

A nanosecond composite shock wave generator based on a vacuum-sealed environment, including an upper insulating flange, a lower metal flange, and an insulating tube, a vacuum-sealed cavity whose air pressure is much lower than the standard atmospheric pressure. The discharge switch, the first waveform forming resistor, the second waveform forming resistor and the third waveform forming resistor; the high voltage end of the energy storage capacitor is electrically connected to the DC high voltage charging end through the first insulating sleeve, and the low voltage end of the DC high voltage charging power supply is connected to the lower metal The flange is connected to the reference ground; the low voltage end of the energy storage capacitor is connected to the lower metal flange; the high voltage end of the energy storage capacitor is connected to one end of the discharge switch, the other end of the discharge switch is connected to the upper end of the first waveform forming resistor, and the first waveform forming resistor lower end The upper ends of the second waveform forming resistor and the third waveform forming resistor are respectively electrically connected, and the lower end of the second waveform forming resistor is connected with the lower metal flange; the upper end of the second waveform forming resistor also leads out the nanosecond composite shock wave generating device through the third insulating sleeve The current output end of the open-circuit current output end, the lower end of the third waveform forming resistor leads out the current output end of the nanosecond composite shock wave generating device through the second insulating sleeve.

Further, the installation branch of the energy storage capacitor is arranged in parallel with the connection branch of the first waveform forming resistor and the second waveform forming resistor, and the two are installed as close as possible. The currents are equal in magnitude and opposite in direction.

Further, the connection branch of the energy storage capacitor and the discharge switch is arranged in parallel with the connection branch of the first waveform forming resistor and the second waveform forming resistor, and the two are installed as close as possible. The currents flowing through are equal in magnitude and opposite in direction.

Further, the discharge switch is in the form of a surface flashover trigger structure. The discharge switch adopts a flat electrode, including an upper electrode, a lower electrode and a trigger electrode. The trigger electrode is coaxially installed in the lower electrode and is electrically isolated by an insulating isolation medium. The upper guide rod and the lower guide rod are respectively connected with the upper end of the first waveform forming resistor and the high voltage end of the energy storage capacitor.

Further, the edge of the plate electrode of the discharge switch is a rounded corner with a certain radius of curvature.

Further, the air pressure of the vacuum-tight cavity is 10 ^-1 Pa to 10 ^-5 Pa.

The invention is based on a nanosecond composite shock wave generating device in a vacuum-sealed environment, which includes a vacuum-sealed cavity whose air pressure is far lower than the standard atmospheric pressure composed of an upper insulating flange, a lower metal flange, and an insulating tube. The forming resistors are installed in a vacuum sealed environment. On the one hand, each element has good insulation and withstand voltage characteristics. On the other hand, it can further reduce the gap distance of the discharge switch. Since the discharge occurs in the same sealed vacuum environment, nanoseconds occur. The components in the loop can be compactly installed and the wiring can be shortened, further shortening the increase in the total loop inductance caused by the wiring, which can reduce the loop wiring inductance, which is beneficial to the generation of nanosecond composite shock waves.

Further, the installation branch of the energy storage capacitor is arranged in parallel with the connection branch of the first waveform forming resistance and the second waveform forming resistance and the two are installed as close as possible, or the installation branch of the energy storage capacitor and the first waveform forming resistance and The connecting branches of the second waveform forming resistor are arranged in parallel and installed as close as possible to the two branches. During the nanosecond impulse discharge, the currents flowing in the two branches are equal in magnitude and opposite in direction, which strengthens the mutual inductance between the two branches. The self-inductance effect of the two branches is almost cancelled, so that the total residual inductance of the composite impulse circuit is minimized.

Further, the discharge switch adopts the form of a surface flashover triggering structure, and the electrodes are flat electrodes and the edges are rounded with a certain curvature radius, so that the two ends of the discharge switch have a uniform electric field. Under the condition of a certain withstand voltage, nanoseconds The path of the pulse current flowing through the switch electrodes is the shortest, and the residual inductance is the smallest.

Description of drawings

Fig. 1 is a schematic diagram of a nanosecond composite shock wave RLC generating circuit of the present invention

Fig. 2 is the structure schematic diagram of the nanosecond composite shock wave generating device of the present invention

Figure 3 is a schematic structural diagram of the second embodiment of the nanosecond composite shock wave generating device of the present invention

Fig. 4 is the structural schematic diagram of the discharge switch of the present invention

In the figure: 1- upper insulating flange, 2- lower metal flange, 3- insulating tube, 4- energy storage capacitor, 5- discharge switch, 6- first waveform forming resistor, 7- second waveform forming resistor, 8 -The third waveform forming resistor, 9-first insulating sleeve, 10-second insulating sleeve, 11-third insulating sleeve, 12-DC high voltage charging end, 13-open circuit current output end, 14-current output end , RL load, LC-energy storage capacitor low-voltage terminal, HC-energy storage capacitor high-voltage terminal, E1-upper electrode, E2-lower electrode, TE-trigger electrode, ID-insulation isolation medium, S1-upper guide rod, S2- Lower deflector.

Detailed ways

The present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments, but it is not intended to limit the present invention.

Referring to FIG. 1 , a schematic diagram of the nanosecond composite shock wave generating circuit of the present invention. It includes an energy storage capacitor 4, a discharge switch 5, an inductance L, a first waveform forming resistor 6, a second waveform forming resistor 7, a third waveform forming resistor 8 and a load RL. In the following, the short-pulse composite shock wave in the electromagnetic environmental effect test method of the lightning current system is taken as an example to illustrate the selection method of the circuit parameters.

The short pulse composite shock wave satisfies the following expression:

i(t)=I _p (-αe ^-αt +βe ^-βt ), where: α=11354s ^-1 , β=647265s ^-1

From this calculation, it can be obtained that the pulse composite shock wave is a function of the decay time of RC, but in practice, the shock wave with zero rise time cannot be realized, because the inductance of the generating circuit itself and the inductance of the wiring exist objectively. Therefore, in the The standard specifies that the peak time of the short pulse composite shock wave is 100ns, and the bottom width time of the waveform is 6.4μs. However, with the increase of loop inductance, the rising process of nanosecond composite shock wave will slow down. Therefore, how to reduce the residual inductance of the composite shock wave generating loop is the key to the generation of nanosecond composite shock wave.

Referring to Figure 1, when the load presents a high impedance, the nanosecond composite shock wave generating device outputs a nanosecond shock voltage wave at both ends of the load. When the load presents a low resistance state, the current flowing through the nanosecond composite shock wave generating device through the two ends of the load is nanoseconds. second impulse current wave.

Referring to Fig. 2 and Fig. 3, the nanosecond composite shock wave generating device of the present invention comprises an upper insulating flange 1, a lower metal flange 2, and an insulating tube 3, which is composed of an air pressure of ^10-1 Pa to ^10-5 Pa. A storage capacitor 4, a discharge switch 5, a first waveform forming resistor 6, a second waveform forming resistor 7 and a third waveform forming resistor 8 are installed in the vacuum sealed cavity; the high voltage end HC of the storage capacitor passes through the first insulating sleeve The tube 9 is electrically connected to the DC high voltage charging terminal 12, the low voltage terminal of the DC high voltage charging power supply is connected to the lower metal flange 2 and is connected to the reference ground; the low voltage terminal LC of the energy storage capacitor is connected to the lower metal flange 2; the high voltage terminal HC of the energy storage capacitor It is connected to the left end of the discharge switch 5, the right end of the discharge switch 5 is connected to the upper end of the first waveform forming resistor 6, and the lower end of the first waveform forming resistor 6 is electrically connected to the upper end of the second waveform forming resistor 7 and the third waveform forming resistor 8 respectively. connection, the lower end of the second waveform forming resistor 7 is connected to the lower metal flange 2; the upper end of the second waveform forming resistor 7 leads out the open-circuit current output end 13 of the nanosecond composite shock wave generating device through the third insulating sleeve 11, and the third waveform The lower end of the forming resistor 8 leads out the current output end 14 of the nanosecond composite shock wave generating device through the second insulating sleeve 10 .

Referring to FIG. 4, the discharge switch 5 of the present invention adopts the structure form of creeping trigger and flat electrode, including an upper electrode E1, a lower electrode E2 and a trigger electrode TE, and the trigger electrode TE is coaxially installed in the lower electrode E2, and passes through the insulating isolation medium ID Electrical isolation, the discharge switch 5 is respectively connected with the upper end of the first waveform forming resistor 6 and the high voltage end HC of the energy storage capacitor through the upper guide rod S1 and the lower guide rod S2; in order to reduce the corona discharge phenomenon during the charging process, the discharge switch 5 The edges of the plate electrodes are all rounded structures with a certain curvature radius, so that there is a uniform electric field at both ends of the discharge switch, and because the axial distance of the plate electrodes is much shorter than the discharge path of the spherical electrodes, the nanosecond impulse current The path through the switch electrode is the shortest, that is, the equivalent inductance of the discharge switch 5 is the smallest.

Referring to FIG. 2 , the storage capacitor 4 is installed in parallel with the branches of the first waveform forming resistor 6 and the second waveform forming resistor 7 and as close as possible. Referring to Fig. 3, or the discharge branch of the energy storage capacitor 4 and the discharge switch 5 are parallel to the first waveform forming resistor 6 and the second waveform forming resistor 7 branch and installed as close as possible; The currents flowing in the circuit are equal in magnitude and opposite in direction, which strengthens the mutual inductance between the two branches and almost cancels the self-inductance of the two branches, thereby minimizing the total residual inductance of the composite impulse circuit.

In the present invention, the energy storage capacitor 4, the discharge switch 5, the first waveform forming resistor 6, the second waveform forming resistor 7 and the third waveform forming resistor 8 are all installed in a closed vacuum environment. On the one hand, the excellent vacuum insulation makes each element It has good insulation and withstand voltage characteristics. On the other hand, the components in the nanosecond generating circuit can be compactly installed, which further shortens the increase in the total inductance of the circuit caused by the connection, which is conducive to the generation of nanosecond composite shock waves.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: Modifications or equivalent substitutions are made to the specific embodiments, and any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention shall all be included in the scope of the present claims.

Claims (4)

1. A nanosecond composite shock wave generating device based on a vacuum airtight environment, characterized in that: the air pressure comprising the upper insulating flange (1), the lower metal flange (2), and the insulating tube (3) is far lower than the vacuum of the standard atmospheric pressure. A sealed cavity, wherein an energy storage capacitor (4), a discharge switch (5), a first waveform forming resistor (6), a second waveform forming resistor (7) and a third waveform forming resistor (8) are installed in the vacuum sealed cavity The high voltage terminal (HC) of the energy storage capacitor is electrically connected with the DC high voltage charging terminal (12) through the first insulating sleeve (9), and the low voltage terminal of the DC high voltage charging power source is connected with the lower metal flange (2) and connected to the reference ground; The low voltage end (LC) of the energy storage capacitor is connected to the lower metal flange (2); the high voltage end (HC) of the energy storage capacitor is connected to one end of the discharge switch (5), and the other end of the discharge switch (5) forms a resistor (6) with the first waveform ) upper ends are connected, the lower ends of the first waveform forming resistor (6) are respectively electrically connected with the upper ends of the second waveform forming resistor (7) and the third waveform forming resistor (8), and the lower end of the second waveform forming resistor (7) is electrically connected with the lower metal flange (2) connected; the upper end of the second waveform-forming resistor (7) also leads out the open-circuit current output end (13) of the nanosecond composite shock wave generating device through the third insulating sleeve (11), and the third waveform-forming resistor (8) ) the lower end leads out the current output end (14) of the nanosecond composite shock wave generating device through the second insulating sleeve (10); The installation branch of the energy storage capacitor (4) is arranged in parallel with the connection branch of the first waveform forming resistor (6) and the second waveform forming resistor (7), and the two are installed as close as possible to each other. , the currents flowing in the two branches are equal in magnitude and opposite in direction; Or the connection branch of the energy storage capacitor (4) and the discharge switch (5) is arranged in parallel with the connection branch of the first waveform-forming resistor (6) and the second waveform-forming resistor (7), and the two are installed as close to each other as possible. , during the nanosecond impulse discharge, the currents flowing in the two branches are equal in magnitude and opposite in direction. 2. The device according to claim 1, characterized in that: the discharge switch (5) is in the form of a surface flashover triggering structure, and the discharge switch (5) adopts a flat electrode, comprising an upper electrode (E1), a lower electrode ( E2) and the trigger electrode (TE), the trigger electrode (TE) is coaxially installed in the lower electrode (E2), and is electrically isolated by the insulating isolation medium (ID), and the discharge switch (5) passes through the upper guide rod (S1), the lower The guide rod (S2) is respectively connected with the upper end of the first waveform forming resistor (6) and the high voltage end (HC) of the energy storage capacitor. 3 . The device according to claim 2 , wherein the edge of the plate electrode of the discharge switch ( 5 ) is a rounded corner with a certain curvature radius. 4 . 4 . The device according to claim 3 , wherein the air pressure of the vacuum-tight chamber is 10 ^-1 Pa to 10 ^-5 Pa. 5 .

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