CN107332107A - A kind of pulse power postpones pseudospark switch with magnetic - Google Patents

Abstract

This disclosure discloses a magnetically delayed pseudo-spark switch for pulse power, which includes a pseudo-spark switch and a magnetic switch. The magnetic switch is connected in series to the anode end of the pseudo-spark switch. The pseudo-spark switch is composed of an insulating shell, a hollow cathode, a hollow anode and a trigger pole, and the pressure in the sealed cavity formed by the insulating shell, the hollow cathode, and the cover plate of the hollow anode is 1-100Pa. The opposite ends of the hollow cathode and the hollow anode are provided with a number of circular holes, and the diameter of the holes and the distance between the two ends are both 3-5mm; the trigger electrode is arranged inside the cavity of the hollow cathode, and the discharge form is a pseudo-spark discharge. The volt-second product parameter of the magnetic switch must be sufficient to cause the current to flow in large quantities after the voltage on the pseudo-spark switch drops to a very low value. The effect of the magnetic delay greatly reduces the conduction loss and electron energy of the pseudo-spark switch, reduces the anode ablation, and accelerates the current rising speed at the same time.

Description

A Magnetically Delayed Pseudo-Spark Switch for Pulse Power

technical field

The disclosure belongs to the fields of pulse power technology, gas lasers, extreme ultraviolet lithography power supplies, etc., and particularly relates to a magnetic delayed spark switch for pulse power.

Background technique

High-voltage pulse discharge switch is one of the key devices in pulse power technology, and it plays an increasingly important role in high-power microwave, gas laser, extreme ultraviolet lithography, particle accelerator, etc. Long-term research has been carried out on high-voltage pulse discharge switches at home and abroad. Common forms include high-pressure switches, magnetic switches, solid-state switches, and pseudo-spark switches. However, there are inherent defects in a single device that are difficult to overcome. Compared with the limitations encountered by a single switching device, the magnetic delay switching technology using magnetic switches in conjunction with other switches shows great potential for development in repetitive frequency pulsed power systems.

The magnetic delay pseudo-spark switch is composed of a magnetic switch and a pseudo-spark switch connected in series. The magnetic switch is essentially a saturable inductor with excellent repetition frequency performance and can work at a high repetition frequency of tens of kilohertz. Compared with the gas switch, there is no problem of insulation recovery and electrode ablation. Compared with the semiconductor switch, the withstand voltage and Large flow capacity. However, high-voltage applications have high requirements on the volt-second product of magnetic switches, and the problems of slowing down the pulse front or increasing the volume of the magnetic core are more prominent. Pseudo-spark switch is a kind of pulse power switch with great development potential. Compared with other gas switches such as high-pressure spark gap switch, vacuum trigger switch and hydrogen thyratron, etc., it has small size, large discharge current rise steepness, and Small delay and jitter, strong flow capacity, small electrode ablation, long life, 100% reverse current can pass, fast medium recovery speed, repetition frequency can even reach 100kHz, etc. In the specific application, it was found that there are still many problems to be solved in the high repetition frequency pseudo-spark switch, such as large conduction loss, which leads to heat generation of the switch, limitation of repetition frequency working time, life and stability; serious anode ablation, which affects the entire life Discharge stability during the process; insulation recovery speed needs to be further improved.

Contents of the invention

Based on this, the present disclosure discloses a magnetic delay pseudo-spark switch for pulse power, and the pseudo-spark switch includes a magnetic switch (1) and a pseudo-spark switch (2);

The magnetic switch (1) is used to delay the rise time of the current;

The pseudo-spark switch (2) is used to bear the high voltage of pulse discharge;

The magnetic switch (1) includes a high-voltage insulated wire (3) and a ring magnetic core (4);

The high-voltage insulated wire (3) is wound on the ring magnetic core (4);

The pseudo-spark switch (2) includes an anode cover plate (5), a cathode cover plate (6), a hollow anode (7), a hollow cathode (8), an insulating shell (9) and a trigger unit (11);

The anode cover plate (5), the cathode cover plate (6) and the insulating shell (9) form a closed cavity;

The interior of the insulating casing includes a hollow anode (7), a hollow cathode (8) and a trigger unit (11).

The present disclosure has the following technical effects:

1. This disclosure provides a new type of high-voltage pulse discharge switch using magnetic delay switch technology. This switch has a very high current rise rate, very low conduction loss, low electrode ablation rate and extremely long life.

2. The opposite end surfaces of the hollow cathode and the hollow anode described in the present disclosure are provided with a number of circular holes, the diameter of which is 3-5mm, and the distance between the discharge occurrence surfaces of the two electrodes is 3-5mm; the trigger electrode passes through the cathode through the insulating sleeve The cover plate is arranged inside the hollow cathode cavity; the discharge is initiated by the trigger electrode and develops along the axis of the cathode hole and the anode hole, and the discharge plasma expands to the area around the hole, and the discharge form is a pseudo-spark discharge.

3. The volt-second product parameter of the magnetic switch described in this disclosure must meet certain requirements, which is enough to make the current flow in large quantities after the voltage drops to a very low value during the conduction process of the pseudo-spark switch.

Description of drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present disclosure;

Fig. 2 is a schematic structural diagram of an embodiment of the present disclosure;

Fig. 3 is a schematic structural diagram of an embodiment of the present disclosure;

Among them, magnetic switch (1) and pseudo-spark switch (2), high-voltage insulated wire (3), ring magnetic core (4), anode cover plate (5), cathode cover plate (6), hollow anode (7), hollow Cathode (8), insulating shell (9), insulating medium sheet (10), trigger unit (11), trigger electrode (12), insulating sleeve (13), insulating sleeve (14).

detailed description

The structural principle and working principle of the present invention will be further described in detail below in conjunction with the accompanying drawings.

In one embodiment, the present disclosure discloses a magnetic delay pseudo-spark switch for pulse power, including a magnetic switch (1) and a pseudo-spark switch (2);

The magnetic switch (1) is used to delay the rise time of the current;

The pseudo-spark switch (2) is used to bear the high voltage of pulse discharge;

The magnetic switch (1) includes a high-voltage insulated wire (3) and a ring magnetic core (4);

The high-voltage insulated wire (3) is wound on the ring magnetic core (4);

The pseudo-spark switch (2) includes an anode cover plate (5), a cathode cover plate (6), a hollow anode (7), a hollow cathode (8), an insulating shell (9) and a trigger unit (11);

The anode cover plate (5), the cathode cover plate (6) and the insulating shell (9) form a closed cavity;

The interior of the insulating casing includes a hollow anode (7), a hollow cathode (8) and a trigger unit (11).

The working principle of this embodiment is: after the trigger pulse is applied to the trigger pole, the voltage at both ends of the pseudo-spark switch drops rapidly, but the current is cut off by the magnetic switch, which is almost negligible. During the transition from unsaturated state to saturated state of the magnetic switch, the plasma inside the pseudo-spark switch can be fully developed and multiplied. Once the magnetic switch is saturated, a large current flows quickly in the loop, and at this time the voltage drop on the pseudo-spark switch has dropped to a very low value. Therefore, the effect of the magnetic delay greatly reduces the conduction loss and electron energy of the pseudo-spark switch, reduces the anode ablation, and accelerates the current rising speed at the same time.

In one embodiment, the magnetic switch (1) is connected in series with the hollow anode (8) of the pseudo-spark switch (2).

In one embodiment, the number of turns of the high-voltage insulated wire (3) wound on the annular magnetic core (4) varies from one turn to several turns and is evenly distributed;

The materials of the annular magnetic core (4) are selected from ferrite and nanocrystals;

The material for making the high-voltage insulated wire core wire is copper, and the material for the insulating sheath is silica gel.

In this embodiment, the high-voltage insulated wire forms a coil on the magnetic core, conducts current and insulates the inner metal core wire from the magnetic core, and the specific number of turns of the high-voltage insulated wire depends on the volt-second product of the magnetic core required in actual use The purpose of parameter selection is to achieve a suitable withstand voltage amplitude and pulse width capability, as well as a suitable delayed current rise time.

The reason why the material of the annular magnetic core (4) of this embodiment is ferrite and nanocrystalline is: the hysteresis loops of these two magnetic cores are closer to a rectangle and have good high-frequency performance. Compared with materials such as silicon steel sheets, the production Magnetic switches with the same volt-second product parameters require smaller magnetic cores, and are suitable for applications in the field of repetitive frequency pulse power.

In one embodiment, the internal pressure of the airtight cavity formed by the anode cover plate (5), cathode cover plate (6) and insulating casing (9) is 1-100Pa.

In this embodiment, the working air pressure range of the pseudo-spark switch is 1-100Pa, and it works on the left half of the Baschen curve.

In one embodiment, the end surfaces of the hollow anode (7) and the hollow cathode (8) are provided with round holes with a diameter of 3-5 mm, and are parallel to each other with a distance of 3-5 mm.

Under the dimensional structure of this embodiment, the pseudo-spark switch has a high withstand voltage capability and facilitates hollow cathode discharge.

In one embodiment, the trigger unit (11) is arranged inside the hollow cathode (8) and faces the circular hole on the cathode.

In this embodiment, the trigger unit (11) is arranged inside the hollow cathode (8), and facing the circular hole on the cathode is to achieve a better triggering effect. It can also be triggered when it is not facing directly, but the triggering effect Deterioration will occur.

In one embodiment, the pseudo-spark switch also includes a self-made high-voltage pulse generator and an insulating bushing (13);

The self-made high-voltage pulse generator cooperates with the trigger unit to generate a trigger signal;

The trigger signal is introduced through an insulating sleeve (13) and is insulated from the cathode cover plate (6).

In this embodiment, the trigger signal is generated by a self-made high-voltage pulse generator. The principle is that the mains power is rectified into DC by the full bridge and charged to the capacitor. The capacitor discharges the primary side of the pulse transformer through a solid-state switch such as IGBT or MOSFET, and the pulse The secondary side of the transformer outputs a high-voltage pulse signal, which is introduced through an insulating bushing (13) and insulated from the cathode cover plate (6).

In one embodiment, the trigger unit (11) includes an insulating dielectric sheet (10) and a trigger electrode (12);

The insulating medium sheet (10) is sandwiched between two trigger electrodes (12) and is in contact with the two trigger electrodes (12).

In one embodiment, the trigger unit (10) comprises a thin metal needle, the diameter of which is less than 1 mm.

In one embodiment, referring to Fig. 1, this embodiment includes a magnetic switch (1) and a pseudo-spark switch (2). The magnetic switch (1) is composed of a wire (3) wound on a ring magnetic core (4). The structure of the false spark switch (2) comprises an anode cover plate (5), a cathode cover plate (6), an insulating casing (9), a hollow anode (7) and a hollow cathode (8) positioned inside the insulating casing, and a trigger unit ( 11). The magnetic switch (1) is connected in series with the anode of the pseudo-spark switch (2), the number of turns of the winding wire varies from one to several and is evenly distributed, and the typical materials of the magnetic core (4) are ferrite and nanocrystals. The internal pressure of the airtight cavity formed by the anode cover plate (5), the cathode cover plate (6) and the insulating shell (9) is 1-100Pa. The end faces of the hollow anode (7) and the hollow cathode (8) are provided with round holes with a diameter of 3-5mm, which are parallel to each other with a distance of 3-5mm. The trigger unit (11) is arranged inside the hollow cathode (8) and faces the cathode circular hole; the trigger signal is introduced through the insulating sleeve (13) and is insulated from the cathode cover plate (6). The trigger unit (11) is composed of an insulating dielectric sheet (10) and a trigger electrode (12). The insulating medium sheet (10) is sandwiched between the two trigger electrodes (12) and is in close contact with the two.

The magnetic delay pseudo-spark switch described in this embodiment is different from the general pulse discharge switch, and the parameters of the two main parts of the magnetic switch (1) and the pseudo-spark switch (2) need to cooperate with each other. The volt-second product parameter of the magnetic switch must meet certain requirements, which is enough to make the current flow in large quantities after the voltage drops to a very low value during the conduction process of the pseudo-spark switch. In addition, the discharge form generated by the trigger unit (11) during operation is creeping discharge, and the discharge form generated by the pseudo-spark switch (2) during operation is hollow cathode discharge.

In one embodiment, referring to Fig. 2, this embodiment includes a magnetic switch (1) and a pseudo-spark switch (2). The magnetic switch (1) is composed of a wire (3) wound on a ring magnetic core (4). The structure of the false spark switch (2) comprises an anode cover plate (5), a cathode cover plate (6), an insulating casing (9), a hollow anode (7) and a hollow cathode (8) positioned inside the insulating casing, and a trigger unit ( 10). The magnetic switch (1) is connected in series with the anode of the pseudo-spark switch (2), the number of turns of the winding wire varies from one to several and is evenly distributed, and the typical materials of the magnetic core (4) are ferrite and nanocrystals. The internal pressure of the airtight cavity formed by the anode cover plate (5), the cathode cover plate (6) and the insulating shell (9) is 1-100Pa. The end faces of the hollow anode (7) and the hollow cathode (8) are provided with round holes with a diameter of 3-5 mm, which are parallel to each other and have a distance of 3-8 mm. The trigger unit (10) is arranged inside the hollow cathode (8) and faces the circular hole of the cathode; the trigger signal is introduced through the insulating sleeve (11) and is insulated from the cathode cover plate (6). The trigger unit (10) is composed of a thin metal needle, the diameter of which is less than 1mm.

The magnetic delay pseudo-spark switch described in this embodiment is different from the general pulse discharge switch, and the parameters of the two main parts of the magnetic switch (1) and the pseudo-spark switch (2) need to cooperate with each other. The volt-second product parameter of the magnetic switch must meet certain requirements, which is enough to make the current flow in large quantities after the voltage drops to a very low value during the conduction process of the pseudo-spark switch. In addition, the discharge form generated by the trigger unit (11) during operation is field electron emission, and the discharge form generated by the pseudo-spark switch (2) during operation is hollow cathode discharge.

In one embodiment, referring to Fig. 3, this embodiment includes a magnetic switch (1) and a pseudo-spark switch (2). The magnetic switch (1) is composed of a wire (3) wound on a ring magnetic core (4). The structure of the pseudo-spark switch (2) includes an anode cover plate (5), a cathode cover plate (6), an intermediate electrode (9), an insulating casing (10), a hollow anode (7) and a hollow cathode (8) located inside the insulating casing. ), and the trigger unit (12). The magnetic switch (1) is connected in series with the anode of the pseudo-spark switch (2), the number of turns of the winding wire varies from one to several and is evenly distributed, and the typical materials of the magnetic core (4) are ferrite and nanocrystals. The internal pressure of the airtight cavity formed by the anode cover plate (5), the cathode cover plate (6) and the insulating shell (10) is 1-100Pa. The end faces of the hollow anode (7) and the hollow cathode (8) are provided with round holes with a diameter of 3-5mm, which are parallel to each other with a distance of 3-5mm. The trigger unit (12) is arranged inside the hollow cathode (8) and faces the cathode circular hole; the trigger signal is introduced through the insulating sleeve (14) and is insulated from the cathode cover plate (6). The trigger unit (11) is composed of an insulating dielectric sheet (11) and a trigger electrode (13). The insulating medium sheet (11) is sandwiched between the two trigger electrodes (13) and is in close contact with the two.

The magnetic delay pseudo-spark switch described in this embodiment is different from the general pulse discharge switch, and the parameters of the two main parts of the magnetic switch (1) and the pseudo-spark switch (2) need to cooperate with each other. The volt-second product parameter of the magnetic switch must meet certain requirements, which is enough to make the current flow in large quantities after the voltage drops to a very low value during the conduction process of the pseudo-spark switch. In addition, the discharge form generated by the trigger unit (11) during operation is creeping discharge, and the discharge form generated by the pseudo-spark switch (2) during operation is hollow cathode discharge. The middle electrode (9) is located between the hollow anode (7) and the hollow cathode (8), and the distance to the two electrodes is equal, between 3-5mm. There is a circular hole in the center of the middle electrode (9), the diameter of which is the same as that of the hollow anode (7) and the hollow cathode (8), and the three small holes are coaxial. The middle electrode (9) can not only operate at a floating potential, but also can be used by dividing the voltage between the cathode and the anode through the capacitance resistance.

The above embodiments are only used to illustrate the technical solutions of the present invention, rather than 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; Modifications are made to the recorded technical solutions, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical descriptions of the embodiments of the present invention.

Claims (10)

1. a kind of pulse power postpones pseudospark switch with magnetic, it is characterised in that：The magnetic delay pseudospark switch is opened including magnetic Close (1) and pseudospark switch (2)；

The magnetic switch (1) is used for the rise time of delayed current；

The pseudospark switch (2) is used for the high voltage for undertaking pulsed discharge；

The magnetic switch (1) includes high-voltage insulating wire (3) and toroidal core (4)；

The high-voltage insulating wire (3) is wound on toroidal core (4)；

The pseudospark switch (2) includes anode cover plate (5), negative electrode cover plate (6), hollow anode (7), hollow cathode (8), insulation Shell (9) and trigger element (11)；

The anode cover plate (5), negative electrode cover plate (6) and insulation crust (9) constitute airtight cavity；

Include hollow anode (7), hollow cathode (8) and trigger element (11) inside the insulation crust.

2. magnetic according to claim 1 postpones pseudospark switch, it is characterised in that preferred, the magnetic switch (1) and puppet The hollow anode (8) of spark switch (2) is in series.

3. magnetic according to claim 1 postpones pseudospark switch, it is characterised in that：It is described to be wound on toroidal core (4) High-voltage insulating wire (3) the number of turn from a circle to some circles not wait and be uniformly distributed.

4. magnetic according to claim 1 postpones pseudospark switch, it is characterised in that：The material choosing of the toroidal core (4) With ferrite and nanocrystalline；

The material selection copper of the high-voltage insulating wire cored wire, the material selection silica gel of insulation sheath.

5. magnetic according to claim 1 postpones pseudospark switch, it is characterised in that：The anode cover plate (5), negative electrode cover plate (6) and insulation crust (9) constitute airtight cavity internal pressure be 1~100Pa.

6. magnetic according to claim 1 postpones pseudospark switch, it is characterised in that：The hollow anode (7) and hollow the moon The end face of pole (8) is provided with 3~5mm of diameter circular hole, and parallel relative, and spacing is 3~5mm.

7. magnetic according to claim 6 postpones pseudospark switch, it is characterised in that：The trigger element (11) is arranged in sky The heart-yin pole (8) is internal, and just to the circular hole on negative electrode.

8. magnetic according to claim 7 postpones pseudospark switch, it is characterised in that：

The pseudospark switch also includes self-control high-voltage pulse generator and insulating sleeve (13)；

The self-control high-voltage pulse generator coordinates with trigger element (11) produces trigger signal；

The trigger signal is introduced by insulating sleeve (13), and is mutually insulated with negative electrode cover plate (6).

9. magnetic according to claim 8 postpones pseudospark switch, it is characterised in that：The trigger element (11) includes insulation Media sheet (10) and trigger electrode (12)；

The dielectric thin slice (10) is sandwiched between two trigger electrodes (12), and is in contact with two trigger electrodes (12).

10. magnetic according to claim 8 postpones pseudospark switch, it is characterised in that：The trigger element (10) includes one Root metal fine needle, the diameter of fine needle is less than 1mm.