JPH08172780A - Impulse voltage/current generating apparatus - Google Patents

Abstract

PURPOSE: To remove the contaminated material on the surface of an electrode formed when a current is generated by providing the function, which applies a voltage corresponding to the using voltage of intermediate discharge-gap switches on an intermediate point and discharges and cleans the surface of the discharging electrode. CONSTITUTION: When a voltage is applied on an intermediate point CP of discharge-gap switches GSa and GSb and discharge cleaning operation is performed, a discharging switch S2 of a main capacitor is opened after the large-current discharging operation of a main circuit is finished. A forced grounding switch S1 is closed, and the state without charge is set. A charging switch S3 is closed, and the specified voltage is applied on the intermediate point CP from a charging power supply DCG. Discharging is performed between the intermediate point CP of the discharge-gap switches GSa and GSb and discharging electrodes 1 and 2. At this time, when the dielectric strength between the respective discharge electrodes of the discharge-gap switches GSa and GSb is lowered, discharging is performed by the current which is suppressed by a resistor r3, and the electrode is discharged and cleaned. Thus, the withstand voltage is recovered to the specified value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock voltage / current generator for discharging charging energy stored in a capacitor by an air discharge gap switch.

[0002]

2. Description of the Related Art FIG. 2 shows a basic circuit of a conventional shock voltage / current generator. The main switch C is charged by a charging power supply DCG for a main capacitor through a charging resistor Rg by closing a charging switch S2. The charging energy stored in the capacitor C is generated instantaneously by the discharge of the air discharge gap switch GS and is supplied to the load L by generating a large current.

In the above air discharge gap switch GS, an intermediate electrode 3 is provided between the discharge electrodes 1 and 2, and an intermediate potential of the voltage applied between the discharge electrodes 1 and 2 is applied to the intermediate electrode 3 to discharge. The potential gradient between the electrodes is made uniform to maintain the withstand voltage, and at the time of starting, the pulse voltage generated by the trigger pulse generator PG is applied to the intermediate electrode 3 through the trigger capacitor C1 to start the discharge, and the discharge is performed. The withstand voltage between the electrodes may be adjusted by increasing or decreasing the interval length between the discharge electrodes, and may be adjusted by the pressure of the gas in the switch container.

FIG. 4 is a circuit diagram of a conventional multi-stage impact voltage generator. A main capacitor C is charged in parallel with a power supply DCG for charging the main capacitor through a charging resistor Rg, and the air discharge gap switches G1, G2, G3,... Gn are discharged in series, and an impact voltage is generated between the output terminals TH and TL and supplied to the load L. The air discharge gap switch G1 has a structure in which a needle end gap or the like is provided to provide a trigger for starting, for example, Rs is a braking resistor for waveform adjustment, and Ro is a discharge resistor.

[0005]

In the above air discharge gap switch, when the energizing time is several μs and the energizing capacity per time is 0.01 coulomb or less, the discharging is performed even if the voltage is applied again after one energizing. Although the influence on the withstand voltage between the electrodes is small, the withstand voltage between the discharge electrodes after one energization shows variations and decreases as the passing electricity amount increases. For example, when the amount of electricity passed is 2 coulombs, the withstand voltage after discharge shows a variation of 30-90% with respect to the initial withstand voltage. In this state, it is not possible to stably operate a device using many air discharge gap switches. It will be impossible.

[0006] As described above, the reason why the withstand voltage between the discharge electrodes is reduced after the large current discharge is that the metal surface of the discharge electrode during the large current discharge evaporates and the gas around the discharge electrode, such as air and carbon dioxide gas, is removed. This is because the metal oxide fine particles and the metal powder formed by the bonding adhere to the surface of the discharge electrode and the breakdown voltage is reduced.

[0007]

SUMMARY OF THE INVENTION The present invention is an impact voltage / current generator which eliminates the above-mentioned disadvantages, and discharges energy stored (charged) in a main capacitor using an air discharge gap switch. In a device for generating a shock voltage or a current, two air discharge gap switches each comprising a pair of discharge electrodes are connected in series, and the connection point is set as an intermediate point when the main capacitor is not charged. To apply a voltage corresponding to the working voltage of the air discharge gap switch to the surface of the discharge electrode, thereby providing a function of discharging and cleaning the surface of the discharge electrode.

That is, the charging power source DCG shown in FIG. 1, the charging switch S2, the charging resistor Rg, and the main capacitor C
A discharge resistor Ro, a forced ground switch S1, an air discharge gap switch GSa, GSb, a trigger pulse generator PG and a trigger capacitor C1, a load L, a cleaning power switch S3, a resistor r3, High resistance r1, r
2 is a shock voltage / current generator.

In the above device, the main capacitor C connects the charging switch S2 and the charging resistor Rg in series and connects them in parallel to the output terminal of the charging power supply DCG, and also connects a series circuit of the discharging resistor Ro and the forced ground switch S1. Connect in parallel,
In addition, two high voltage terminals are connected to the discharge electrode 1 of the air discharge gap switch GSa connected in series.

Next, the load L is connected between the output terminal TH and the ground terminal TL of the discharge electrode 2 of the two series air discharge gap switches GSb.

The above air discharge gap switch G
Sa and GSb are each composed of a set of two discharge electrodes 1 and 2, which are connected in series, and the connection point is an intermediate point CP, and a trigger pulse is generated between the intermediate point CP and a ground terminal TL. The device PG and the trigger capacitor C1 are connected in series, the series circuit of the resistor r3 and the cleaning power switch S3 is connected to the charging power supply DCG or another direct current power supply which substitutes for this, and the high resistances r1 and r2 are respectively provided. Midpoint C
P and the discharge electrodes 1 and G of the air gap switch GSa
This is an impact voltage / current generator configured as a circuit connected to the Sb discharge electrode 2.

[0012]

[Action] Impact voltage using air discharge gap switch
When a large current is discharged from the current generator and the withstand voltage of the air discharge gap switch falls below the operating voltage, and when the main capacitor is not charged when the capacitor is not in operation, the air discharge gap switch comprising a pair of two discharge electrodes. Are connected in series, and the connection point is defined as an intermediate point. When a voltage corresponding to the working voltage of the discharge gap switch is applied between the intermediate point and the discharge electrode of each air discharge gap switch, the withstand voltage is reduced. Discharge occurs between discharge gaps.

The discharge current is sufficiently suppressed by the resistor r3 shown in FIG. 1 and does not generate metal oxides or fine metal powders on the surface of the discharge electrode which may occur during large current discharge of the main capacitor. Also, it serves to remove the contaminants on the electrode surface that have caused the decrease in the withstand voltage of the electrode surface that occurs when the large current is generated, and restores the withstand voltage of the discharge gap switch.

[0014]

[Embodiment 1] FIG. 1 shows a circuit of a shock voltage / current generator of the present invention, in which a series circuit of a charging power supply DCG, a cleaning power supply switch S3 and a resistor r3 is formed in the basic circuit of FIG. The circuit configuration is such that a cleaning discharge voltage is applied to an intermediate point CP where the gap switches GSa and GSb are connected in series.

In the above circuit, the discharge gap switches GSa and GSb have a pressurizing structure housed in a closed container or an exposing structure under atmospheric pressure, and the selection thereof is determined by design requirements. The potential at the intermediate point CP, which is a series connection between the discharge gap switches GSa and GSb, is set to be approximately the intermediate value of the voltage applied between the discharge electrode 1 of the discharge gap switch GSa and the discharge electrode 2 of GSb, and the high resistances r1, r
Set by dividing the pressure by 2. The voltage to be applied is the charging power supply DC
Since the output voltage is in the range of G, the present embodiment has a circuit configuration that shares the power supply. Of course, a dedicated power supply may be used as the power supply.

In the above circuit, the values of the currents flowing through the high resistances r1 and r2 are each sufficient to be about 100 μA or less, and the resistance r3 is the intermediate point of two discharge gap switches connected in series and the discharge electrode 1 or 2. It is provided in order to suppress the current to several mA when a short circuit occurs between them, and the value may be sufficiently smaller than the values of the high resistances r1 and r2.

In the circuit of the present invention, the operation for applying the voltage to the intermediate point CP of the discharge gap switches GSa and GSb to perform the discharge cleaning operation is as follows. After the high-current discharging operation of the main circuit is completed, the main capacitor charging switch S2 is opened, and the forced grounding switch S1 is closed to bring the main capacitor into a non-charged state. The charging switch S3 is closed, and a predetermined voltage is applied to the intermediate point CP by the charging power supply DCG, so that the intermediate point CP of the discharge gap switches GSa and GSb and the discharge electrodes 1, 2
Discharge between. At this time, the discharge gap switch GS
If the withstand voltage between the discharge electrodes a and GSb is reduced, the discharge is performed with the current suppressed by the resistance r3, the electrodes are discharged and cleaned, and the withstand voltage of each discharge electrode recovers to a predetermined value.

[0018]

[Embodiment 2] FIG. 3 is a circuit diagram of another embodiment of a multi-stage shock voltage / current generator equipped with a discharge cleaning circuit of the present invention, in which two discharge gap switches are connected in series and an intermediate point CP is formed.
To form a set, and the discharge gap switch GS1
To GS13 in a multi-stage series configuration. In the above circuit, the discharge resistor Ro has a function of discharging the device and a function of applying a potential to the intermediate point CP of each discharge gap switch at the time of discharge cleaning, and the voltage supplied from the discharge cleaning power supply DCG2 is supplied by the main capacitor C. The voltage is divided and a predetermined voltage is applied to an intermediate point CP of each discharge gap switch. S11, S
A high-voltage switch 12 is closed during discharge cleaning and grounded to form a discharge cleaning circuit.

With the circuit formed as described above, the main capacitor C is grounded at the time of discharge cleaning, and the discharge cleaning power supply DCG
When a high voltage is applied by 2, a voltage is applied to the midpoint CP of each of the two discharge gap switches in series, and the other discharge electrodes become the ground potential, so that the discharge electrodes of each discharge gap switch can be discharged and cleaned.

[0020]

As described above, in the shock voltage / current generator of the present invention, two air discharge gap switches are connected in series, and the connection point is set as an intermediate point, and the air discharge gap is set at the intermediate point. By applying a high voltage equivalent to the operating voltage of the switch and passing a minute discharge current between the electrodes with a reduced withstand voltage, the conductive contamination products generated on the surface of the discharge electrode due to the large current discharge can be removed. It is possible to restore the dielectric breakdown voltage between electrodes of the discharge gap switch to a predetermined value.

With the above-mentioned effects, the cleaning work of the discharge electrode, which has been conventionally performed manually, becomes unnecessary.
The most difficult multi-stage impact voltage exceeding ten meters above ground
A great effect can be exerted on the reliable operation, maintenance and operation of the current generator, and work safety, and the present invention has industrial and practical value.

[Brief description of drawings]

FIG. 1 shows two aerial discharge gap switches of the present invention.
FIG. 2 is a circuit diagram of an impact voltage / current generating device connected in series as a set and provided with a discharge cleaning circuit.

FIG. 2 is a basic circuit diagram of a conventional shock voltage / current generator.

FIG. 3 is a circuit diagram of an embodiment of a multistage shock voltage generator of the present invention.

FIG. 4 is a circuit diagram of a conventional multi-stage shock voltage generator.

[Explanation of symbols]

DCG, DCG1: Power supply for charging DCG2: Power supply for discharge cleaning C: Main capacitor GS, GSa, GSb, GS1 to GS13, G1 to G
7: Air discharge gap switch 1, 2: Discharge electrode CP: Midpoint PG: Trigger pulse generator C1: Trigger capacitor L: Load S1: Forced ground switch S2: Charge switch S3: Cleaning power switch S11, S12 : High-voltage switch Rg: Charge resistance Ro: Discharge resistance r1, r2: High resistance r3: Resistance RS: Braking resistance R1: Current control resistance TH, TL: Output terminal E: Ground

Claims (1)

[Claims] 1. A charging power source (DCG), a charging switch (S2), a charging resistor (Rg), a main capacitor (C), a discharging resistor (Ro), and a forced grounding switch (S).
1) and air discharge gap switch (GSa, GSb)
, A trigger pulse generator (PG) and a trigger capacitor (C1), a load (L), and a cleaning power switch (S)
3) An impact voltage / current generator comprising a resistor (r3) and a high resistor (r1, r2), wherein a main capacitor (C) comprises a charging switch (S2), a charging resistor (Rg), Are connected in series to the output terminal of the charging power supply (DCG) in parallel, the series circuit of the discharge resistor (Ro) and the forced ground switch (S1) is connected in parallel, and two high voltage terminals are connected in series. The load (L) is connected to the discharge electrode (1) of the air discharge gap switch (GSa), and the output terminal connected to the discharge electrode (2) of the two series air discharge gap switches (GSb). (TH) and a ground terminal (TL), and the air discharge gap switches (GSa, GSb)
A pair of two discharge electrodes (1, 2) are connected in series, and the connection point is defined as an intermediate point (CP).
A trigger pulse generator (PG) and a trigger capacitor (C1) are connected in series between P) and a ground terminal (TL), and a series circuit of a resistor (r3) and a cleaning power switch (S3) is charged. Power supply (DCG) or another alternative DC power supply and a high resistance (r1, r
2) are connected to the intermediate point (CP) and the discharge electrode (1) of the air discharge gap switch (GSa) and the discharge electrode (2) of (GSb), respectively. Generator.