DE102013225835A1 - Range radio link - Google Patents

Abstract

The invention relates to a series spark gap having at least one first spark gap (FS1) with a first main electrode (FSA1) and a second main electrode (FSA2) and a second spark gap (FS2) with a first main electrode (FSA3) and a second main electrode (FSA4), wherein the second main electrode (FSA2) of the first spark gap (FS1) is connected in series with the first main electrode (FSA3) of the second spark gap (FS2), each of the spark gaps (FS1, FS2) having an auxiliary starting electrode (H1, H2), wherein the auxiliary ignition electrodes (H1, H2) are interconnected via a switching circuit (ZK), the first main electrode (FSA1) of the first spark gap (FS1) and the second main electrode (FSA4) of the second spark gap (FS2) being terminals (A1, A2 ) are available for the series spark gap.

Description

The invention relates to a series spark gap.

Background of the invention

In many applications of electrical devices impulses, especially high-energy pulses, such as those that occur in lightning, represent a serious risk.

In order to counter these dangers, more and more surge protection devices are used. In particular, for high-energy pulses, the derivative has proven by means of spark gaps. Although varistors are also usable in principle, it has been found that spark gaps provide a better reduction of the residual voltage after ignition of the spark gaps to a desirably low level compared with a varistor-based solution.

Once a spark gap has ignited, a conductive connection is made across the arc gap and the pulse is dissipated therefrom. Various mechanisms are available for ignition. For example, by a targeted use of a high-voltage pulse, a breakdown between the electrodes of a spark gap can be brought about. However, the provision of such a targeted high-voltage pulse is possible only with complex wiring.

A cheaper alternative is possible by means of auxiliary electrodes, as for example in the EP 1 566 868 B1 the applicant is disclosed. An exemplary spark gap FS ₁ is in 1 shown. In this case, a resistive (resistive) conductive connection between one of the main electrodes FSA _{2 of} a spark gap and an auxiliary electrode H ₁ is used. However, this resistive (resistive) conductive compound has only a comparatively low current carrying capacity. If the current exceeds the current carrying capacity, an arc plasma is produced and, as a result of the ionization resulting therefrom, the main ignition gap between the main electrodes FSA ₁ and FSA ₂ becomes more rapidly conductive.

In particular on high-performance (direct voltage as well as alternating voltage) networks, it is necessary to provide a sequence current extinguishing capability corresponding to the power to be switched.

In order to provide this sequence current extinguishing capability in systems with high nominal voltages, ie voltages above 230 V or above 400 V, series connections are usually used for cost reasons. The voltage across the series circuit of spark gaps is thus divided into two or more spark gaps. In 2 an exemplary arrangement of spark gaps FS ₁ and FS _{2 is} shown. Both spark gaps have their own ignition circuit, which is formed here by way of example in the spark gap FS ₁ by means of a gas-filled surge arrester GDT ₁ and a varistor VAR ₁ , and the example here at the spark gap FS ₂ also by means of a gas-filled surge arrester GDT ₂ and a varistor VAR _{2 is} formed.

In the known variants of series connection of spark gaps can not be ensured due to the independent ignition circuits that ignite both spark gaps simultaneously. This is for example in 3 the example of the series connection of 2 shown. There, the voltage at the series spark gap caused by the exemplary impulse initially rises sharply and, after a few μs, the one spark gap (approximately after 5 μs) ignites, whereupon the voltage, which initially also rises sharply, shows a first break-in. Nevertheless, the tension is still very high. Only after approximately another 5 μs does the ignition of the further spark gap occur and thus a greater decrease in the current. 3 So it clearly shows that the spark gaps become conductive in time. The voltage curve gradually drops to the level of the respective spark gap withstand voltage. The residual voltage level is very high due to the series-connected ignition circuits.

That by a serial ignition of the spark gaps, the residual voltage remains at a high level for a longer time, which is undesirable. In addition, in a delayed ignition of another ignition circuit this longer and thus more heavily loaded. Thus, the ignition circuit must be designed for a higher load to provide a delayed ignition, which in turn leads to higher costs. If the ignition circuit is not designed accordingly for a higher load, again threatens danger.

The object of the invention is to provide an improved arrangement which, on the one hand, provides cost-effective and, on the other hand, rapid and reliable lowering of the residual voltage.

The object is achieved by the features of the independent claims. Advantageous embodiments of the invention are specified in the subclaims.

The invention will be explained in more detail with reference to the accompanying drawings with reference to preferred embodiments.

Show it

1 a schematic representation of a spark gap with auxiliary electrode for use in embodiments of the invention,

2 a schematic representation of a series connection of two spark gaps with auxiliary electrode according to the prior art

3 a diagram showing the relationship between current and voltage in the series connection 2 points out,

4 a schematic representation of a series connection of two spark gaps with auxiliary electrode according to embodiments of the invention, and

5 a diagram showing the relationship between current and voltage in the series connection 4 shows.

4 shows a schematic representation of a series connection of two spark gaps with auxiliary electrode according to embodiments of the invention.

The series spark gap has at least one first spark gap FS ₁ with a first main electrode FSA ₁ and a second main electrode FSA ₂ . Furthermore, the series spark gap has at least one second spark gap FS ₂ likewise with a first main electrode FSA ₃ and a second main electrode FSA ₄ . Of course, even more spark gaps can be provided in the series circuit.

The second main electrode FSA _{2 of} the first spark gap FS ₁ is connected in series with the first main electrode FSA _{3 of} the second spark gap FS ₂ .

Each of the spark gaps FS ₁ , FS ₂ has at least one auxiliary starting electrode H ₁ , H ₂ . The Zündhilfselektroden H ₁ , H ₂ are connected to each other via a circuit ZK, wherein the first main electrode FSA _{1 of} the first spark gap FS ₁ and the second main electrode FSA _{4 of} the second spark gap FS _{2 are available} as connections A ₁ , A ₂ for the series spark gap ,

That is, the series spark gaps FS ₁ , FS ₂ are provided with a common Zündkreisbeschaltung ZK. The arrangement ensures that the spark gaps switch at the same time.

This is for example in 5 the example of the series connection of 4 shown. There, the voltage caused by the exemplary pulse above the series spark gap initially increases less than in the 3 and it comes after a few μs to ignite the two spark gaps (about after 5 microseconds), whereupon the voltage shows a break-in. Already after this break in the voltage has dropped about as far as in the example of 3 only after 10 μs would be. 5 Thus, it clearly shows that the spark gaps essentially become conductive at the same time. The voltage curve falls directly to the level of the respective spark gap burning voltage. The residual voltage level can also lower than in the series circuit of 3 lie with the same spark gaps. However, this depends on the design of the components of the Zündkreisbeschaltung ZK.

That By means of the presented series connection, an improved arrangement is made available which, on the one hand, is cost-effective and, on the other hand, provides a rapid and reliable lowering of the residual voltage.

In an advantageous embodiment, spark gaps with auxiliary electrodes, as in FIG EP 1 566 868 B1 Applicant discloses, used, ie the auxiliary ignition electrodes H ₁ , H ₂ are arranged in electrically conductive connection to the first main electrode FSA _{1 of} the first spark gap FS ₁ or in electrically conductive connection to the second main electrode FSA _{4 of} the second spark gap FS ₂ . In this case, a resistive (resistive) conductive connection between the main electrodes FSA _{1 of} a first spark gap and a first auxiliary electrode H ₁ or between the main electrodes FSA _{4 of} a second spark gap and a second auxiliary electrode H ₂ is used. However, these resistive (resistive) conductive compounds have only a comparatively low current carrying capacity. If the current exceeds the current carrying capacity, an arc plasma is generated and, as a result of the ionization resulting therefrom, the main ignition gap between the main electrodes FSA ₁ and FSA ₂ or FSA ₃ and FSA ₄ becomes more rapidly conductive.

Of course, other spark gaps with other auxiliary electrodes can alternatively be used.

In an embodiment of the invention, the circuit ZK has a gas arrester GDT ₁ . That is, here too, the advantageous switching behavior of gas discharge tubes can be usefully used for the ignition circuit. The GDT ₁ gas arrester produces the insulation in the normal state. The ignition voltage of the gas discharge line GDT ₁ is in an advantageous embodiment below the ignition voltage of the spark gaps, ie the gas discharge GDT ₁ ignited usefully before the main spark gap.

In yet another embodiment of the invention, the circuit ZK has a varistor VAR ₁ . This means that the advantageous switching behavior of varistors for the ignition circuit can also be usefully used here.

Of course, the circuit ZK may also have other components, but it has been shown that the switching behavior is particularly favorable when the circuit ZK has both a varistor VAR ₁ and a gas discharge GDT ₁ .

In the event of a discharge event, the gas discharger GDT ₁ first ignites in the circuit ZK. The self-adjusting current flows through both auxiliary electrodes H ₁ and H ₂ . Only when the ionization of both spark gaps FS ₁ and FS ₂ is essentially completed does the current commute to the spark gap FSA ₁ and FSA ₂ or FSA ₃ and FSA ₄ as the main leakage path. The load (current integral) of the circuit ZK corresponds to that of a single spark gap of the same construction type, ie only a smaller load has to be taken into account, as it does not lead to a delayed ignition.

In the presented circuit variant, the two spark gaps FS ₁ and FS _{2 are} connected via an "insulated" electrode. That is, the connection of the two spark gaps between FSA ₂ and FSA ₃ is unbound potential. This ensures the common ignition.

In other words, in the event of a discharge event, the gas discharger GDT ₁ first ignites in the circuit ZK. The self-adjusting current flows through both auxiliary electrodes H ₁ and H ₂ . Only when the ionization of both spark gaps FS ₁ and FS ₂ is essentially completed, the current commutes to the spark gap FSA ₁ and FSA ₂ or FSA ₃ and FSA ₄ as the main leakage path.

In a particularly cost-effective variant, the individual spark gaps FS ₁ and FS ₂ used for the series spark gap are essentially identical.

By means of the presented invention, it is thus possible to achieve an ignition delay time less than or equal to the ignition delay time of a single spark gap. The residual stress is thereby greatly minimized early, i. stronger than a normal series connection of spark gaps.

The series connection can also be arranged in a common housing G, as in FIG 4 shown to be provided only with the necessary terminals A ₁ and A ₂ .

LIST OF REFERENCE NUMBERS

FS ₁ , FS ₂

radio link

FSA ₁ , FSA ₂ , FSA ₃ , FSA ₄

main electrode

H ₁ , H ₂

auxiliary ignition

ZK

circuit

A ₁ , A ₂

connections

GDT ₁ , GDT ₂

gas arrester

VAR ₁ , VAR ₂

varistor

G

casing

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 1566868 B1 [0005, 0026]

Claims (5)

Series spark gap with at least one first spark gap (FS ₁ ) with a first main electrode (FSA ₁ ) and a second main electrode (FSA ₂ ) and a second spark gap (FS ₂ ) with a first main electrode (FSA ₃ ) and a second main electrode (FSA ₄ ) wherein the second main electrode (FSA ₂ ) of the first spark gap (FS ₁ ) is connected in series with the first main electrode (FSA ₃ ) of the second spark gap (FS ₂ ), each of the spark gaps (FS ₁ , FS ₂ ) via a starting auxiliary electrode (H ₁ , H ₂ ), wherein the auxiliary ignition electrodes (H ₁ , H ₂ ) via a circuit (ZK) are interconnected, wherein the first main electrode (FSA ₁ ) of the first spark gap (FS ₁ ) and the second main electrode (FSA ₄ ) of the second spark gap (FS ₂ ) as terminals (A ₁ , A ₂ ) are available for the series spark gap. Series spark gap according to claim 1, characterized in that the auxiliary ignition electrodes (H ₁ , H ₂ ) in electrically conductive connection to the first main electrode (FSA ₁ ) of the first spark gap (FS ₁ ) or in electrically conductive connection to the second main electrode (FSA _4th ) of the second spark gap (FS ₂ ) is arranged. Series spark gap according to one of the preceding claims, characterized in that the circuit (ZK) has a gas discharge (GDT ₁ ). Series spark gap according to one of the preceding claims, characterized in that the circuit (ZK) has a varistor (VAR ₁ ). Series spark gap according to one of the preceding claims, characterized in that the first spark gap (FS ₁ ) and the second spark gap (FS ₂ ) are substantially identical.

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