RU2574288C2 - Lightning-proof horn-gap arrester with deion chamber - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: arrester comprises deion chamber (6) for arc-quenching inside the body (1) and facilities to control inner gas flow to regulate characteristics of electric arc occurring at load with pulse current and electric arc stipulated by the mains aftercurrent. Distance is maintained very low between opposite surfaces of the arrester electrodes in the area of ignition. There is only insignificant expansion of distance between them in direction of the arrester end, which prevents undesired movement of electric arc at pulse currents. Gas circulation is envisaged so that blast wave from the arc stipulated by pulse current of the lightening is reflected from deion chamber (6) and/or other obstacles thus preventing movement of electric arc. Gas flow passes through deion chamber (6) with time delay, then it is returned back to the area of ignition and brought to openings made in electrodes for flow guidance thus promoting arc movement at the mains atercurrents occurred in direction of deion chamber (6).

EFFECT: optimal limitation of the mains aftercurrent excluding entry of current pulses with high amplitude to the deion chamber thus increasing service life of the arrester.

13 cl, 6 dwg

Description

Technical field

The invention relates to a lightning protection horn spark gap with a deion chamber for extinguishing an arc in a housing, including with a non-blowing structure, and means for adjusting the differing characteristics of an electric arc arising from a pulsed current load, on the one hand, and an electric arc caused by the aftereffect current network, on the other hand.

State of the art

From the patent document DE 4435968 C2 a surge protection element for rejection of transient overvoltages based on a horn spark gap is known. In it, each electrode of the horn spark gap has an element for connection and a spark horn, and the spark horns of electrodes located at a distance from each other form a punctured air spark gap. In addition, inside the casing of the overvoltage protection element, a flat electrode damping device is provided having several flat damping electrodes that are located opposite the ends of the spark gap electrodes remote from the connection elements at a distance from these ends of the electrodes.

Known spark gap is made with blowing the arc and therefore requires extensive and costly measures to protect it. In order to realize sufficient current limitation, as well as durability when resisting the appearing thermal and mechanical loads, the spark gap of the patent document DE 4435968 C2 has an electric arc separation, namely separation using two deion chambers, which also leads to additional costs.

For modern lightning protection arresters mounted in sectional housings and used in the field of low voltage, there is a requirement to perform them encapsulated. Such lightning protection arresters must have a high efficiency of quenching the aftereffect current of the network, as well as a high degree of limiting the current of the aftereffect of the network.

Patent documents EP 1535378 B1 or EP 0860918 B1 show lightning arresters with deion chambers for sectional built-in devices which are made by blowing, but in which, however, the exhaust gases are at least partially deionized. These spark gaps do not provide the possibility of functional separation between the emerging pulsed currents and the aftereffects of the network.

In general, the application of the principle of limiting the aftereffect current of a network through deion chambers in lightning rods, which is widespread in the field of low voltages, is problematic. An effective limitation of the aftereffect current of a network using deion chambers is based on the rapid entry of an electric arc into the corresponding arcing chamber. The time before entering the arcing chamber is short if a small distance between the place of ignition and the deion chamber and a high speed of movement of the electric arc are realized. However, the speed of movement of the electric arc depends on many parameters, namely, among other things, on the material of the electrodes, on the aerodynamic drag, on the design and on the corresponding forces that act on the electric arc.

Since, when the goal is to severely limit the network aftereffect current, the instantaneous value of the network aftereffect current should always be less than the magnitude of the impulse currents supplied, a contradiction arises, since the forces supporting the movement of the electric arc increase with increasing electric current, in accordance with the Lorentz rule.

In well-known horn spark arresters, this leads to the fact that, when the electric arc of the after-effects of the network quickly enters the arcing chamber and with a good limitation of the after-effects of the network, the longest pulsed currents also enter the deion chamber, and, thus, also have high energy pulse currents of lightning. This means that the deion chamber used must be designed thermally and dynamically for supplied pulsed currents.

The voltage of the electric arc and with it the power conversion in the corresponding horn spark gap increases significantly when the arc is divided into several partial electric arcs, since no current limitation occurs when the pulsed currents are supplied. Therefore, the load on all parts of the spark gap increases significantly. This is especially critical for encapsulated devices, since power conversion takes place completely within the arrester. In contrast, arrester arresters give up to 90% of the converted power in the surrounding space.

An alternative to having to withstand this heavy load inside the arrester is to temporarily delay the entry of an electric arc into the chamber by increasing the intervals or distances. As a result of this, the electric arc of the pulse current is prevented from entering the chamber of the electric arc, however, the resulting limitation of the aftereffect current of the network is unacceptable. Regarding this, reference can be made to patent document DE 2419731 B2.

Disclosure of invention

From the foregoing, the objective of the invention is to create an improved lightning protection horn spark gap with a deion chamber, which, on the one hand, has an optimal limitation of the aftereffect current of the network and, on the other hand, avoids the input of high-amplitude pulsed currents into the deion chamber, which ensures high service life and wear resistance.

The solution of the problem of the invention is achieved through a combination of features of a technical solution according to paragraph 1, wherein the dependent claims represent at least expedient embodiments and improvements of the invention.

In a lightning-proof horn spark gap according to the invention, including with a non-blowing design, different behavior of the electric arc is caused at the aftereffect currents and at pulsed currents. As a result of this, an economically feasible and compact design of the deion chamber, as well as diverging electrodes, is achieved, the thermal and mechanical load on the spark gap is reduced, it becomes possible to reduce the cost of preventing blowing phenomena, and also increase the service life. It also implements a simple, inexpensive and compact device for ignition in the form of a starting electrode.

Using the solution according to the invention, it is possible to reduce the load on the deion chamber created due to the supplied pulsed lightning currents, up to its complete elimination. In a first embodiment of the invention with non-blowing, i.e. In the encapsulated design of the horn spark gap, an electric arc of a pulsed current is fixed inside the ignition region of diverging electrodes due to the special shape of the ignition region and the targeted control of pressure wave reflections within the spark gap, while the electric arc of the aftereffect of the network for a significantly shorter period of time enters arc chamber and limited.

The idea according to the invention comes from a lightning protection horn spark gap with a deion chamber for extinguishing an arc in a housing with a non-blowing structure and controlling the internal gas flow to regulate the different characteristics of the electric arc arising from the load by the pulse current, on the one hand, and the electric arc due to the aftereffect of the network , on the other hand.

To this end, the distance between the opposite surfaces of the electrodes of the horn spark gap in the ignition region is kept very small in order to prevent undesired movement of the electric arc with pulsed lightning currents. In addition, opposite surfaces of the electrodes in the ignition region extend substantially parallel to each other or have only a very slight extension of the distance between them towards the end of the horn spark gap. As a result of these geometric measures in the field of ignition, the effect of forces on the electric arc of the pulsed current is minimized. In addition to this, shock waves produced by an electric arc, which occurs during the discharge of a pulsed lightning current in the ignition region of a spark gap, form certain reflections on obstacles with which the stream meets in front of the deion chamber, on it or also behind it. The force impact of the reflected shock wave or shock waves is used to further reduce or compensate for the electric current forces that could cause an undesirable displacement of the electric arc of the pulsed lightning current in the direction of the deion chamber. The effectiveness of these reflections for fixing the electric arc is limited, in particular, by pulsed currents due to lightning, and is also limited in time. With the measures used, the intensity and duration of the effective forces of the reflection front depends on the magnitude, duration and energy content of the pulsed current caused by lightning, so that this makes, in particular, the critical high-energy pulsed lightning currents very effectively fixed in the place of ignition of the arc.

The application of the measures explained above is also possible in a fully encapsulated horn spark gap with a deion chamber to limit the electric arc current due to the aftereffect current without drift of the pulsed lightning current into the deion chamber caused by internal gas circulation, which also contributes to the mobility of the aftereffect current. The gas flow passing through the deion chamber, in such a spark arrester coming with a time delay, at least partially returns to the area of motion of the electric arc of the spark arrester by means of deflecting means.

As already presented, an arrangement in the ignition region of the starting electrode is possible.

The starting electrode includes an electrically conductive element that is surrounded by a spark gap of the surface discharge or has adjacent spark gaps of the surface discharge of an insulating or semiconducting material.

The start electrode is inserted either in one of the two electrodes in the ignition region or between the two electrodes of the horn spark gap, and is preferably located in the lower part of the ignition region.

Spark gaps in the surface discharge can be asymmetric or asymmetrical.

The solution according to the invention allows to minimize the forces arising due to the amplitude of the electric current to the level of the pulsed lightning current due to the special design of the ignition region and the use of reflection of shock waves inside the lightning rod.

An electric arc of a pulsed current at the beginning of its appearance tends to a diffuse form. This form favors the existence of several bases of the electric arc and not yet very focused arc. As a result of too narrowing of the electric arc or its cooling by adjacent elements, such as anti-friction elements of the casing walls, ceramic plates, etc., at the initial stage of the electric arc, the power conversion in the plasma increases, and the electric arc quickly transfers to the state of thermal plasma. In this state, the compression of the electric arc is much more pronounced, and the electric arc is more susceptible to the forces acting on it, which contribute to undesirable displacement during the load by the pulsed lightning currents.

The above effect is counteracted by reducing the distance between the electrodes in the ignition region to values less than 1.2 mm, preferably 0.8 mm. Moreover, the active surfaces of the electrodes within the ignition region are located at approximately the same distance. This approximately equal distance takes place, in particular, in the region above the ignition point in the direction of movement of the electric arc. Due to slight initial expansion, i.e. due to the minimal change in the distance between the diverging electrodes, the "run-out" of the electric arc is prevented or limited. The degree of initial expansion of the distance between diverging electrodes should be a maximum of 50%.

The width of the active surface of the electrodes in the preferred embodiment is at least 2 mm. For pulsed currents up to 50 kA, an active electrode width of 2 mm to 6 mm is preferable and sufficient.

It has been found that it is necessary to realize a current density of less than 2 kA / mm ² , preferably 1 kA / mm ² , with respect to the amplitude of the supplied pulsed current under normal atmospheric conditions, in order to constructively prevent the arcing from unraveling in the region of its beginning.

The sufficiently large surface of the electrodes, insignificant tearing and insignificant length of the electric arc make it possible to reduce, in particular, in the phase of the arc before reaching thermal equilibrium, the action of forces, which leads to undesirable movement of the electric arc into deion chambers. Thus, the thermal time constant of an electric arc in air can be about 10 μs to 100 μs.

Since with the help of the mentioned measures it is impossible to infinitely delay the compression of the electric arc caused by the pulse current, at the latest in the region of the trailing edge of the lightning pulse after reaching thermal equilibrium, the electric arc will be compressed and subjected to increased force. In this critical phase according to the invention, the shock wave reflection generated by the described construction of the obstacles in the flow path of the gas circulation will act.

Along with reducing the impact of electric current forces in a design with diverging electrodes for an electric arc of a pulsed current, in the presented spark gap with internal gas circulation, the flow cross section and flow resistance are formed in such a way that the reflection of the shock wave produced by the pulsed current itself counteracts the movement of the electric arc.

To this end, an increase in resistance to flow in the inlet zone of the deion chamber can serve as a reflection front, but also resistance to flow when air is released from the deion chamber.

In order to optimize the effect of pressure reflection, the propagation velocity of the shock wave in the corresponding medium must be taken into account. In this case, the first reflected shock wave does not have to meet an electric arc before reaching the "own exposure time", which depends, among other things, on the material and amounts to several tens of microseconds. It is believed that time gaps significantly larger than 100 μs, or exceeding the time of half amplitude reduction in the section of the trailing edge of the pulse, should be avoided.

Due to the geometric characteristics of the spark gap in the ignition region of the spark gap, only the minimal forces that could cause the arc to move in the direction of the deion chamber act on the electric arc of the pulsed lightning current. Reflections created by an obstruction or obstructions in the flow path lead to shock waves that reach the electric arc of the lightning impulse current at the latest after the "own exposure time" and, if possible, also act until the time reaches half the decrease in amplitude in the region of the trailing edge of the current pulse, as well as sufficiently compensate for the forces driving the electric arc with their oppositely directed force. To achieve this goal, shock waves of reflection from one or more obstacles arranged in series on the flow path are intentionally created. Through these measures, reflected pressure waves of different durations or frequencies are created, and their individual forces distributed over time or also the superposition of these forces are used during the critical period.

A brief description of the graphic materials

Below the invention is explained in more detail on the basis of a variant implementation, as well as with the involvement of the figures of the drawings.

Showing:

figa is a schematic illustration of a lightning protection horn spark gap according to the invention, with a design of diverging electrodes and a circuit diagram of a deion chamber;

fig.1b is a detailed image of the ignition region of the electrodes of the horn spark gap;

figure 2 is a side view according to the image in figure la with the shown direction of gas flow back to the holes for the flow in the electrodes of the horn spark gap;

figure 3 - the combination of the graphs of electric current and voltage of a conventional closed horn spark gap with a deion chamber with a pulse E and load F from the currents of the aftereffect of the network;

Fig. 4 is a view similar to that shown in Fig. 3, however, with the characteristics of the electric current and voltage of the horn spark gap according to the invention;

figure 5 - image of the ignition region of the horn spark gap with a starting electrode, which is built into one of the electrodes of the spark horn of the spark gap, and

6 is a depiction of the ignition region in the design of a lightning protection horn spark gap according to the invention with a starting electrode between the two slightly diverging main electrodes.

The implementation of the invention

On the basis of figa, a fundamental embodiment of the design of a lightning protection horn spark gap according to the invention is understood.

In this case, the spark gap device is mounted in a sectional housing 1 and has two connecting terminals 2.

The spark gap has two slightly diverging electrodes 3 and 4 with recesses 5 for gas circulation and flow around the electric arc of the aftereffect current.

Between strongly divergent sections of the electrodes 3 and 4 in their final region is a deion chamber 6 with openings for gas circulation.

The section of movement of the electric arc between the ignition region (see the detailed image according to Fig.1b) and the deion chamber 6 is limited to the sides by insulating plates (see Fig.2, pos.8).

The deion chamber 6 preferably has air outlets from separate portions of the deion chamber located alternately on different sides. These holes are placed both on the sides and on the end side of the deion chamber 6.

In the area of movement of the arc of the spark gap, gases are removed through the aforementioned side recesses 5 in the electrodes 3 and 4. Moreover, these side openings for the flow or recess 5 are located above the region in which the electric arc stagnates during the load with a pulsed electric lightning current (see Fig. 1b).

For the purposeful separation of backward-flowing gases in separate recesses or openings 5 for flow, in order to better maintain the movement of the electric arc at the aftereffect current, the amount of gas flowing from the deion chamber is divided by splitter 7 into several separate gas streams.

In addition, this splitter 7 prevents the direct flow of gas from the deion chamber 6 to the side recesses 5, as a result of which, even with very strong loads of the electric arc, still heated and / or ionized gases do not return to the region of motion. In addition, the supply of combustion products or associated particulate matter is prevented.

The splitter 7 is, for example, in the form of a small dividing wall, located at an angle, and is located in the region of decreasing gas pressure, i.e. in the area into which gases from the area of motion and from the chamber of the electric arc. The splitter 7 serves in this area as a dividing or deflecting wall for gases that are supplied from the electric arc chamber with a still high temperature and which are again brought to the area of electric arc movement through the grooves in the electrodes on both sides. A relatively direct focused gas stream from the electric arc chamber encounters a splitter and splits into two streams with longer paths - among other things, to lower the temperature and to distribute in the form of a diffuse stream - both of which enter the gas supply openings in the area of the electrodes. Thus, the still heated gas is divided into two streams from two sides, is cooled and further prevents free conductive particles from entering the electrode region. Existing splitters contribute to an even distribution of chilled gas between all openings for the reverse flow in the area of movement of the electric arc. This uniform separation is of great importance for optimally maintaining the characteristics of the electric arc movement of the aftereffect current. For example, when using only one recirculation hole, a relatively thin electric arc of the aftereffect current could easily remain without the effect of targeted internal circulation of the gas that supports the movement. This would lead in a counterproductive way to the passage of the electric arc for too long from the ignition point to the chamber of the electric arc or even to the stagnation of the electric arc, as a result of which the spark gap could fail. Thus, the splitter supports the initial main function of encapsulation of the horn spark gap, namely, targeted internal circulation of the gas to ensure the characteristics of the electric arc movement of the aftereffect current and thereby to limit and suppress the aftereffect current.

The cross section of the recesses 5 in the electrodes is selected to be very insignificant in comparison with the outlet openings of the deion chamber 6 and in the embodiment is at least 10% of the cross section of the opening of the air outlets.

Figure 1b shows in detail the ignition region of the electric arc, which is formed between the electrodes 3 and 4 below the recesses 5 for gas circulation.

Arc ignition can occur actively or passively.

In this case, an electric arc arises between both electrodes 3 and 4 in region A.

The distance between the electrodes in region A in the embodiment is from 0.8 mm to 1.2 mm.

The surface on which the electric arc remains during loading by an electric pulse current of lightning passes at most to region B. The maximum expansion of the distance between diverging electrodes with respect to region A at location B is 50%.

The resulting surface of the electrodes between regions A and B corresponds in the minimum case to that surface which is obtained as the quotient of dividing the maximum amplitude of the supplied electric pulse current by the preferred current density of 1 kA / mm ² .

Figure 2 shows a cross section of a deion chamber, as well as the arrangement of preferred reflection areas.

Here, in turn, it is also necessary to proceed from the sectional mounting case 1 with a spark gap and a visible electrode 4, as well as side recesses 5 for circulating gas between the deion chamber 6 and the region of motion of the electric arc.

The area of movement of the electric arc is limited by insulating protective plates 8.

An electric arc 9 of the aftereffect current of the network passes along diverging electrodes 3, 4 to the inlet region C of the deion chamber 6 and then is divided into separate sections of the chamber. The deion chamber 6 has outlet openings (shown by arrows) on the sides and on the end side, with which air is removed from the regions between the individual flat damping electrodes with a V-neck of the deion chamber. Separate flat quenching electrodes with V-shaped cutouts inside the deion chamber 6 are represented by a dotted line.

On the front side of the deion chamber, the air outlet is also divided in the direction of the axis of the chamber, by an insulating jumper 10.

The aerodynamic drag in the inlet region C of the deion chamber 6, along with the choice of the distance between the individual flat electrodes, the shape of the V-shaped cut-out and the distance from the first individual flat damper of the deion chamber to the corresponding electrodes or guide plates 3, 4, is also affected by the following measures.

V-shaped cutouts of the deion chamber can additionally become clogged with insulation.

In the lateral insulating plates 8, the areas of electric arc movement below the deion chamber 6 may contain additional restrictions as obstacles to the flow.

The number, size and shape of the exhaust openings can affect and define the aerodynamic drag in the air discharge region D of the deion chamber 6.

The described possibility of placing an obstacle to the flow below the deion chamber serves to create a reflection front near the region of fixation of the electric arc of the pulsed lightning current. At the same time, due to this measure, the acceleration of the electric arc of the aftereffect current into the deion chamber occurs. Mentioned wedge-shaped narrowing, located on both sides in the area of movement of the electric arc, can be used very flexibly to control aerodynamic drag by varying the wedge shape up to a massive wedge and, accordingly, the residual width of the channel.

However, it is also possible to change the aerodynamic drag due to the volume and geometry of the channels of the return flow near the deion chamber 6 and above it. In principle, in order to facilitate the fixation of the electric arc of the pulsed current in the immediate vicinity of the ignition region (see Fig. 1b) of the electrodes 3, 4, shock wave reflections are suitable both in the inlet range C and in the air outlet region D. Decisive for the choice of the most favorable reflection area are, in accordance with the form of execution of the spark gap, the requirements with respect to the maximum permissible impulse load and damping capacity with the electric current of the aftereffect of the network.

Presented according to the invention, the measures cause reliable fixation of pulsed lightning currents with a holding time of the order of several milliseconds in the ignition region between section A and section B of the spark gap.

With the expected current of the aftereffect of the network, for example, 50 kA, entry into the deion chamber 6 and its limitation, on the contrary, occurs within a maximum of one millisecond. In this case, the instantaneous value of the aftereffect currents is limited to a few kA. The effectiveness of the measures according to the invention is traced by comparing the images of FIGS. 3 and 4.

Figure 3 shows the combination of the characteristics of the electric current (bottom) and voltage (top) in a conventional closed horn spark gap with a deion chamber with a pulse (E) and the load with currents of the aftereffect of the network (F).

It can be seen that with pulsed current, due to the high steepness of the graph of the electric current and high amplitude, the electric arc enters the deion chamber very soon. The energy load of the deion chamber due to the supplied pulsed current, which can hardly be limited when it enters the chamber, is very high. The parts of the entire spark gap are extremely stressed due to pressure and heat load. The energy turnover in the deion chamber at 25 kA 10/350 μs is in the range up to 7 kJ.

Due to the implemented limitation of the aftereffect current, the specific energy at the expected electric aftereffect current of the 25 kA network is only 2 kA ² s. When loaded with a pulse current of 25 kA 10/350 μs, this value, on the contrary, is approximately 100 times greater. However, when executing the spark gap according to the invention, it is possible to calculate the parameters of the chamber parts for the electric arc or the entire spark gap for a significantly lower energy load. Material subjected to strong energy loads, and therefore expensive, is required exclusively in the ignition region of the horn spark gap between sections A and B.

In figure 4. a characteristic of a closed horn spark gap according to the invention is shown. Changing the voltage of the electric arc and limiting the current under load by the current of the aftereffect of the network (F) correspond to the same characteristics (F) of FIG. 3. When loaded with a pulsed electric current (E), the electric arc according to the invention is fixed in the ignition region of both electrodes, so that the thermal and dynamic load of the entire spark gap is reduced to a small fraction of the load of the spark gap, corresponding to the graph in Fig. 3, due to a significantly lower voltage arcs.

In the embodiment of the spark gap according to the invention, the energy turnover at a pulse load of 25 kA in the form of a pulse of 10/350 μs is reduced by at least ten times compared with the spark gap without the corresponding functional separation with respect to the after-current of the network and the pulsed lightning current.

Due to the performance of the spark gap, possibly non-blowing, according to the invention it is possible to drastically reduce the energy turnover, which, due to encapsulation, loads all the details of the spark gap by 100%. As a result of this, in turn, it becomes possible to reduce the structural dimensions, and this reduces the structural costs. In the end, simpler and therefore less expensive materials find application.

In a further embodiment, the ignition region is formed using a starting electrode.

In this case, it is possible to resort to execution in the form of an air spark gap in accordance with Fig. 5 and / or in the form of a spark gap of a surface discharge in accordance with Fig. 6.

Figure 5 shows an embodiment with a starting electrode 11 in the ignition region. The starting electrode 11 and the spark gap 12 of the surface discharge are conducted through a recess inside one of the two main electrodes 3, 4 or on its surface. This option is suitable, in particular, for the execution of the spark gap between the two main electrodes 3, 4 without a spark gap for surface discharge.

In addition, the ignition device shown in FIG. 5 is very thermally and mechanically protected due to the heat-resistant material of the corresponding main electrode and is thus particularly durable. This is a particular advantage of the presented embodiment of the horn spark gap, since the fixation of the electric arc of the pulse current in the ignition region loads the starting electrode more heavily. Moreover, in the presented embodiment, the location of the starting electrode is especially simple to realize the small interval necessary for the shown embodiments between the two main electrodes 3, 4 with very good insulation resistance values.

As an alternative to the arrangement of the trigger electrode 11 between the two diverging main electrodes, the lateral arrangement of the trigger electrode is also acceptable.

According to Fig.6, the starting electrode 11 is located between the two main electrodes 3 and 4. In this case, the starting electrode 11 is located inside the two spark gaps 13, 14 of the surface discharge. With the preferred asymmetric design of the spark gaps 13, 14 of the surface discharge, it is also possible to select a higher, in the vertical direction, location of the spark gap 14 of the surface discharge and / or make it thicker. As a result of this, insulation resistance also increases. The execution of one or both of the spark gaps of the surface discharge in the form of air gaps is also within the scope of the invention.

Spark gaps 12, 13 of the surface discharge, which are pierced by ignition of the spark gap, can be made in accordance with the prior art as purely insulating gaps or as a combination of an insulating gap having a negligible breakdown voltage, with a continuation of the electrical material that is punched by electrical an arc.

In the case of a clean insulation gap, the use of a pulse transformer provides increased ignition voltage. In the embodiment with an electrically conductive material as an auxiliary element for breakdown, in principle, only a voltage switch is required.

In the presented variants with a trigger, it is assumed that due to the small distances between both main electrodes 3, 4, if necessary, a very short ignition delay time of the spark gap as a whole is selected, as a result of which the energy load and, accordingly, also the structural dimensions are also very small. In addition, the small distance between the main electrodes provides, for example, in case of a failure of the starting circuit, the operation of a passive arrester with a protection level of maximum 4 kV.

In an embodiment of the invention with an electrically conductive material serving as an auxiliary element for breakdown, in principle, only a voltage switch and / or an element limiting an electric current, such as a resistor, varistor, posistor or the like, are required.

Claims (13)

1. A lightning-proof horn spark gap with a deion chamber for extinguishing an arc in a housing and means for adjusting the different characteristics of an electric arc arising from a pulsed current load, on the one hand, and an electric arc caused by the aftereffect current of the network, on the other hand, in which a small distance between opposite surfaces of the electrodes of the horn spark gap in the ignition region, while the opposite electrode surfaces in the ignition region have a substantial expansion of the distance between them in the direction of the end of the horn spark gap, and there are openings for flow in the electrodes, while this lightning-proof horn spark gap of a non-blowing structure allows gas to circulate in such a way that the shock wave produced by the electric arc caused by the pulsed lightning current is reflected from the deion chamber and / or from obstacles in the flow path and counteracts the movement of the electric arc, and also in such a way that the gas flow, which passes through the deion chamber, is at least partially retracted back to the ignition region by means of deflecting means and is brought to the flow openings in the electrodes in order to facilitate the movement of the electric arc at the aftereffect currents of the network in the direction of the deion chamber, and for this purpose, the flow openings made, in the direction of the deion chamber, over the ignition region and over the region in which the electric arc stagnates during the load with a pulsed electric current of lightning. 2. The arrester according to claim 1, characterized in that the distance between the opposite surfaces of the electrodes in the ignition region is less than 1.5 mm, preferably in the range from 0.5 mm to 0.8 mm. 3. The arrester according to claim 1 or 2, characterized in that the maximum expansion of the distance between opposite surfaces of the electrodes in the ignition region is 50%. 4. The arrester according to claim 1, characterized in that the width of the surfaces of the electrodes in the ignition region is essentially from 2 mm to 6 mm. 5. The spark gap according to claim 1, characterized in that the device is mounted in a sectional housing, the housing having holes in the form of slots or slots for equalizing the pressure. 6. The spark gap according to claim 1, characterized in that the electric arc motion section is bounded laterally by insulating plates covering the electrodes on the sides, the plates extending from the ignition region to the deion chamber. 7. The spark gap according to claim 1, characterized in that the cross-sectional area of the holes for the flow in the electrodes is substantially smaller than the total area of the openings for the exit of the flow of the deion chamber. 8. The arrester according to claim 1, characterized in that the deion chamber has a plurality of individual flat absorbers located at a distance from each other, each of which has a V-shaped notch, the opening of which is directed towards the horn spark gap, so that by choosing the distance between the individual dampers and / or their additional filling to establish or regulate aerodynamic drag in the inlet region of the deion chamber. 9. The arrester according to claim 8, characterized in that the deion chamber has openings for air outlet, the quantity, size and shape of which are selected from the conditions for adjusting or defining aerodynamic drag in the inlet region of the deion chamber. 10. The arrester according to claim 1, characterized in that a starting electrode is located in the ignition area. 11. The arrester according to claim 10, characterized in that the starting electrode includes an electrically conductive element that is surrounded by a spark gap of the surface discharge or near which there are spark gaps of the surface discharge. 12. The spark gap according to claim 10 or 11, characterized in that the starting electrode is integrated in one of the two electrodes in the ignition region or is located between the two electrodes of the horn spark gap. 13. The spark gap according to claim 11, characterized in that the spark gaps of the surface discharge are asymmetric or asymmetrically arranged.

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