DE1232239B - Compressed air switch - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. CL:

HOIh

German class: 21c-35/10

Number: 1232239

File number: A 52124 VIII d / 21 c

Filing date: April 9, 1966

Opened on: January 12, 1967

The invention relates to a compressed air switch with several series-connected switching elements, each of which comprises a metal container which is arranged at high voltage potential and is constantly filled with compressed air, which contains a power switching point to be operated with compressed air and a circuit connected in parallel with the power switching point, which in turn has a relatively low-resistance damping resistor and contains a relatively high-resistance control resistor ¹ . For switching the two resistors on and off, two resistance switching points, each provided with an actuating member intended for compressed air actuation, are arranged in the compressed air tank. In the case of certain switches, the task of the damping resistor can be to dampen overvoltages that can occur when, for example, long open-circuit lines are switched on. In other switches, the damping resistor can have the task of reducing the steepness and amplitude of the transient recurring voltage across the switch terminals during a switching process and thereby increasing the switching capacity of the switch. The last-mentioned function is particularly important if the switch is to be arranged at such a point in a high-voltage network at which extremely steep slopes of the recurring voltage can occur, e.g. B. when switching off a short circuit that occurs at a distance of a few kilometers from the switch. In order to be able to perform this function effectively, the resistor must be of low resistance, with a relatively large current, e.g. B. of 2 kA, the resistance happens after the power switching point is open. The task of the control resistor is to facilitate the interruption of this current by evenly distributing the voltage to the various series-connected switching elements during the switching process. In the switched-off rest position of the switch, on the other hand, such a uniform voltage distribution is usually achieved with the aid of capacitors connected in parallel with the switching elements.

The problem underlying the invention is how to get the power switch point, the two resistance switch points and the two resistors in a simple and space-saving manner in one for a compressed air switch of the above Type intended switching element is to be arranged. This is achieved according to the invention in that only one of the resistors in the container is placed on a post insulator, while all-compressed air switches

Applicant:

Allmänna Svenska Elektriska Aktiebolaget,
Västeräs (Sweden)

Representative:

Dipl.-Ing. H. Missling and Dipl.-Ing. R. Schlee,
Patent attorneys, Giessen, Bismarckstr. 43

Named as inventor:

Haakon Forwald,

Dr. phil. Walter Pucher,

Karl Gustav Sindahl, Ludvika (Sweden)

Claimed priority:

Sweden April 14, 1965 (4890)

borrowed for the moving contacts of the three switching points provided actuators on the container wall in electrical connection with each other stand. With such an arrangement, a compact design and the switching elements are achieved are simplified in that only a minimum of individual insulating parts is required. Through this, that all actuators are at the same potential, z. B. control air lines metallic material used for the pneumatic interconnection of the actuators will. Such lines are much simpler and more reliable than z. B. Porcelain piping. Another major advantage is that in the open switch position only those for wearing the fixed Contact of the power switching point provided implementation is stressed during the The post insulator for the resistor is only under voltage for a short time during the switching process.

A particularly advantageous further development of the invention is characterized in that the one Resistance switching point, the z. B. have a common fixed contact with the power switching point can, has a movable contact which is arranged on an insulating operating rod, which in is arranged in a manner known per se centrally leading through one of the resistors. The dimensions of the switching element can be further reduced by the fact that the resistances, which are

609 757/285

are moderately cylindrical, with substantially parallel axes and arranged at right angles to the current path of the power switching point.

Two embodiments of the invention are described below with reference to the drawing, in which

F i g. 1 and 2 each have a section through two different ones Show switching elements.

The in Fig. 1 has a metallic container provided with a bushing 1 2 carried by an insulator 3. The container 2, which consists of two communicating with one another Partial containers 4 and 5 exists, is through the hollow insulator 3 in connection with a compressed air supply in the lower part of the switch and is constantly filled with compressed air. The partial container 4 includes one Power switching point, which consists of a fixed contacts carried by the bushing 1 and a movable contact 7 is made. A circle is arranged in parallel with the power switching point 6, 7, which contains a control resistor 8 arranged in the partial container 5 and a damping resistor 9. The control resistor can, for. B. be on the order of a few kilo ohms while the damping resistance is relatively low, for example 100 Ω. For the one and Disconnection of the parallel circuit, a resistance switching point is arranged in the partial container 4, the one has fixed contact in common with the power switching point, while its movable contact 10 by an actuating rod 11 made of insulating material and arranged centrally by the control resistor 8 will be carried. The contact 10 is in communication with the lowermost one through a sliding contact 12 Part of the resistor 8. For switching on and off the damping resistor 9, which is of a hollow post insulator 13 is carried, an additional resistance switching point is arranged, which consists of a fixed contact carried by the resistor 9

14 and a movable contact 15, which by sliding contacts in connection with the wall of the Container 2 stand. The resistance switching point 14,

15 is arranged in the post insulator 13, the inner cavity through openings not shown with the the remaining part of the container 2 filled with compressed air is in communication. For actuation of the power switching point and the moving contacts of the resistance switching point are three actuators

16, 17 and 18 are mounted on the container 2 and are in electrical contact with each other through the wall of the container. The actuators 16 and

17, which may for example be of the type described in German Patent Specification 1 031 396, also have the task of opening and closing flow paths for the compressed air. The three actuators 16, 17 and 18 are pneumatically interconnected by a metallic control air line 19. Between this compressed air line and each actuating element 16, 17 and 18 are throttle elements 20, 21 and 22 for setting the correct operating sequence for the various switch controls arranged. The control air line 19 can be pressurized or pressurized via a hollow control air isolator 23 be vented. The line 19 leads down to the switch frame, where the control air system by means of a Two-way compressed air valve for the purpose of opening or closing the switching points located in the container 2 can either be connected to the rest of the compressed air system of the switch or to the open air.

However, in order to obtain shorter actuation times, it may be useful, especially with the highest occurring operating voltages that the control air line 19 directly from the compressed air tank 2 is fed via a valve arranged at high voltage potential. The switching element shown can by connecting conductors 24 and 25 with one of the nominal voltage and the nominal breaking capacity of the Switch-dependent number of identical switching elements are connected in series, which together form a switch pole.

In Fig. FIG. 2 shows another switching element in which all in FIG. 1 items shown under the the same designations can be found. The only difference between those in Fig. 1 and those in Fig. 2 switching elements shown is the arrangement of the resistors 8 and 9 and the electrical circuit the parallel circles within the container 5. In the arrangement of FIG. 1 are during the Power interruption the two resistors parallel to the power switching point, while in the arrangement according to Fig. 2 only the damping resistor 9 is connected in parallel.

If the low-resistance resistor 9 is provided for damping the recurring voltage when switching, for example, so-called distance errors, the throttle element 20 can be omitted, and the throttle elements 21 and 22 must be adjusted so that the resistance switching point 14, 15 before the resistance switching point 6, 10 opens. If, on the other hand, the damping resistor is provided for damping switch-on overvoltages, the two resistance switching points must switch on before the power switching point.

Claims (7)

Patent claims: 1. Compressed air switch with several series-connected Switching elements with one each arranged at high voltage potential and constantly metal container filled with compressed air, which has a power switching point to be operated with compressed air and a circuit connected in parallel with this, which contains a relatively low-resistance damping resistor and a relatively high-resistance control resistor contains, as well as two each provided with an actuator provided for compressed air actuation Resistance switching points for switching the said damping and switching on and off Control resistors, characterized in that only one of the named, in the container (2) arranged resistors is supported by a post insulator (13), while all for the movable contacts of the three switching points provided actuators via the The container wall are in electrical contact with one another. 2. Compressed air switch according to claim 1, characterized in that the movable contact (10) the one resistance switching point is carried by an insulating actuating rod (11). 3. Compressed air switch according to claim 2, characterized in that the actuating rod (11) is guided centrally through one of the resistors (8). 4. Compressed air switch according to claim 1, 2 or 3, characterized in that the shutdown of the damping resistor (9) Resistance switching point (14, IS) seen is arranged within said post insulator (13). 5. Compressed air switch according to one of the preceding claims, characterized in that that both resistors (8, 9) are cylindrical and have substantially parallel axes. 6. Compressed air switch according to claim 5, characterized in that the axes of the resistors (8, 9) are essentially at right angles to the current path of the power switching point (6, 7). 10 7. Compressed air switch according to one of the preceding claims, characterized in that said container (2) filled with compressed air consists of two communicating sub-containers (4, 5), one of which is the power switching point (6, 7) and the one for disconnection of the control resistor provided resistance switching point (6, 10), while the other contains the two resistors (8, 9) and the other resistance switching point (14,15). 1 sheet of drawings 609 757/285 1.67 O Bundesdruckerei Berlin