EP1020886A2 - High-speed circuit breaker - Google Patents

Abstract

The switch has spaced stationary electrodes (E1,E2) and a cooperating bridging contact (2) which connects the electrodes in the closed switch position, with an explosive charge (4) generating the gas for extinction of the switching arc. the bridging contact is provided by a switch piston and an integral contact sleeve (2') having a gas exit opening (3) which is closed by the hollow stationary electrode (E2) in the closed switch position and which leads to a gas exit chamber (8) in the open switch position. An Independent claim for an application of a high-speed current breaker switch for use with a power switch is also included.

Description

TECHNICAL AREA

The invention is based on an electrical Fast switch according to the preamble of claim 1. The The invention also relates to the use of the quick switch.

STATE OF THE ART

With the preamble of claim 1, the invention takes to a prior art reference, as it is from DE 3 537 314 A1 is known. There is a device for interrupting Current described in which an electrical connection through the Explosion of an explosive charge is separated. A tubular Bridging contact made of ductile material between a 1st and 2. The electrode has notches on the inside as predetermined breaking points and an explosive charge on the outside inside a pressure chamber. If the current to be monitored exceeds a specifiable one Current limit value, the explosive charge is ignited. One of them arcing arises from the pressure chamber Blowing out mixed gas and at the next Current zero crossing deleted. The disadvantage here is that in addition to Explosive charge also the electrodes and the bridging contact must be replaced after each switch-off. By the Arc becomes electronegative gas, as part of the Mixed gas, from the lining of the inner wall of the pressure chamber triggered, which leads to their consumption.

DE 19 613 568 A1 describes a circuit breaker for Operating voltages up to 30 kV known for the 1st and 2nd Electrodes in the closed state by a movable, circular cylindrical switching pin as bridging contact are electrically connected. Is between the electrodes the switching pin is surrounded on the circumference by a pressure chamber. Parallel to the power current path, one with movable Nominal current contacts provided nominal current path can be arranged. At the The circuit breaker first turns off the rated current path interrupted, causing the current on the power track commutates. Then the power path is interrupted. An arc forms, which is then extinguished. The Drive for the switching pin, which when switching a Speed in the range of 10 m / s - 20 m / s can reach is not specified. The switch pin that comes with a Relatively complex switching drive for nominal current contact fingers is connected when switching a high load exposed.

PRESENTATION OF THE INVENTION

The invention as defined in claim 1 solves the task of an electrical quick switch of the beginning continue to develop in such a way that the constructive Effort for cables and switching devices is reduced.

Advantageous embodiments of the invention are in the dependent claims defined.

An advantage of the invention is that electrodes and Bridging contact not renewed after every switching operation Need to become. The simple construction leads to Cost savings.

The quick switch according to the invention can be advantageous as Reserve switches can be used for a circuit breaker.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1

schematisch einen Querschnitt durch die Kontaktbereiche eines Schnellschalters mit einer Sprengladung, rechts im eingeschalteten, links im ausgeschalteten Zustand,

Fig. 2

schematisch einen Querschnitt durch einen Kontaktbereich eines Schnellschalters mit 3 Sprenqladunqen und

Fig. 3

schematisch einen Querschnitt durch die rechte Hälfte der Kontaktbereiche eines Schnellschalters mit zusätzlichen Nennstromkontakten.

The invention is explained below using exemplary embodiments. Show it:

Fig. 1

schematically shows a cross section through the contact areas of a high-speed switch with an explosive charge, on the right when switched on, on the left when switched off,

Fig. 2

schematically shows a cross section through a contact area of a quick switch with 3 Sprenqladunqen and

Fig. 3

schematically shows a cross section through the right half of the contact areas of a high-speed switch with additional nominal current contacts.

WAYS OF CARRYING OUT THE INVENTION

In the figures, the same parts have the same reference numerals featured.

Fig. 1 shows schematically a cross-sectional view through the Contact areas of a high-speed switch with an axis of symmetry or switch axis (A), on the right when switched on, on the left in its off state.

In the upper part of a circular cylindrical switch housing (1) a 1st electrode (E1) with an erosion contact or Burn-up contact pin (K1) and a gas-generating charge or Explosive charge (4) on which an ignition device (4 ') is attached, gas-tight to an underlying one High pressure chamber (6) arranged. In the lower part of the Switch housing (1) is a 2nd electrode or Hollow electrode (E2) with a ventilation line (9) for Venting a low pressure chamber or piston chamber (7) into a Exhaust chamber (8) below the hollow electrode (E2). On tubular bypass contact or switching piston (2) is in Switch-on position of the quick switch on the one hand via Current contact element (K2) with the erosion contact pin (K1) in electrically good conductive sliding connection and on the other hand with the Inner wall of the switch housing (1) in sliding connection. This switching piston (2) has an axial, electrical well-conducting contact tube (2 ') in a central Opening of the hollow electrode (E2) is arranged movably and with the wall of this central opening in electrically conductive Contact is there. The contact tube (2 ') has in its lower Area a gas outlet opening or exhaust opening (3), which in the on position of the quick switch below the top surface of the hollow electrode (E2) and thus through this is closed. Gas from the high pressure chamber (6) can be in this Do not escape the switch-on position through the exhaust opening (3).

By igniting this explosive charge (4) is a chemical Reaction, like a safety airbag (airbag) Motor vehicle, temporarily released a large amount of gas, the through openings or explosion gas inlet openings (5) in the 1. Electrode (E1) flows into the high pressure chamber (6) and there generates a pressure in the range of 5 MPa - 10 MPa. That pressure drives the tubular switching piston (2) in the direction of movement an arrow (B) down. This is the electrical contact between the erosion contact pin (K1) and the Current contact element (K2) interrupted, so that between the Burn-up contact pin (K1) and the inner wall of the contact tube (2 ') forms an arc (10) which in the further course of the Piston movement is extended. If the switching piston (2) is lower position, cf. the left side of Fig. 1, then the exhaust opening (3) is free to the outside, and the Explosion gases from the high pressure chamber (6) can enter the Exhaust chamber (8) escape. The arc (10) blow and within a half period of the to be interrupted AC at the next zero current to go out brought. The vent line (9) in the hollow electrode (E2) ensures that the switching piston (2) is not affected by the Piston chamber (7) compressed gas in its movement is braked.

1. die Bewegung des Schaltkolbens (2) und damit die Trennung des Abbrandkontaktstiftes (K1) von dem Stromkontaktelement (K2) in der gewünschten kurzen Zeit von wenigen ms erfolgt und

2. daß die durch das Abströmen des Explosionsgases erzeugte Beblasung des Lichtbogens (10) ausreicht, um den Strom zu unterbrechen und ggf. eine gewünschte hohe Lichtbogenspannung zu erzeugen.

The pressure in the high-pressure chamber (6) can be adjusted such that the gas-generating explosive charge (4) is suitably dimensioned

1. the movement of the switching piston (2) and thus the separation of the erosion contact pin (K1) from the current contact element (K2) in the desired short time of a few ms and

2. that the blowing of the arc (10) generated by the outflow of the explosion gas is sufficient to interrupt the current and possibly to generate a desired high arc voltage.

Pressures in the range of 5 MPa - 10 MPa can be easily to reach; they allow contact separation times of a few ms a distance between the 1st electrode (E1) and the hollow electrode (E2) of about 10 cm.

The volume of the exhaust chamber (8) is such that the Residual pressure in the high pressure chamber (6) is sufficient to desired dielectric strength of the open contact path to ensure.

After a switching operation, the quick switch can be activated Reset the contact tube (2 ') and replace the gas generating explosive charge (4) made ready for switching again become. In the simplest case, this is done by manual Revision. The readiness to switch off can also be done by one mechanical reset drive and automatic Reloading device for the explosive charge (4) (not shown) be automated.

2 schematically shows a 1 in a cross-sectional view. Electrode (E1 ') with several gas-generating explosive charges (4a, 4b, 4c), which are ignited separately one after the other if necessary can and via separate feed channels to the high pressure chamber (6) are connected. This eliminates the need for use cases with rare switching cases an automatic Reloading device.

Fig. 3 shows schematically in a cross-sectional view the right Half of the contact areas of a high-speed switch, in which to increase the nominal current carrying capacity Arc extinguishing contacts (K1 ', K2) multiple finger contacts or Nominal current contacts (11), only one of which can be seen, are connected in parallel. These current contacts (11) are on the edge between a stationary 1st electrode (E1 ") and the Movable switching piston (2) and arranged by one Compression spring (12) pressed on. The movable switching piston (2) thus serves to carry the nominal current. From this switching piston (2) the current is rigid over several with the switching piston (2) connected webs (2a), one of which is in cross section is shown on a sliding contact (13) from where it is transferred to the resting hollow electrode (E2). The big ones Radii at which the contact transitions take place allow this Carrying high rated currents.

To ensure safe commutation from the rated current contacts (11) to ensure the erosion contact pin (K1 '), this is around an overlap distance (a) of z. B. 1 cm compared to Burn-up contact pin (K1) extended according to FIG. 1.

For the 2nd nominal current transmission from the switching piston (2) to the Hollow electrode (E2) can also be used instead of sliding contacts (13) Rated current contacts (11), as for the 1st rated current transmission from the 1st electrode (E1 ") on the switching piston (2) used become.

It is understood that the current contacts are also different can be shown. So z. B. instead of one from the 1st electrode (E1) of the excellent erosion contact pin (K1) a recess can be provided in the 1st electrode (E1), which on the edge with a current contact element (K2) of the Switching piston (2) is in an electrically conductive sliding connection (not shown). Such a contact recess could also be provided in the erosion contact pin (K1).

The quick switch according to the invention can be used as an additional or Relief switch (back-up) to a not shown Circuit breakers are used whose switching capacity for an expected maximum short-circuit current is not sufficient. In such a situation, the quick switch could be about the middle of a busbar, right at the beginning of a Short circuit, part of the injected short circuit energy disconnect so that the existing circuit breaker only after End of the switching process in the quick switch needs and with the reduced short-circuit current no longer is overloaded.

The quick switch according to the invention can also be used as a fuse or Reserve switch (back-up) at a relatively low Powerful, cost-effective, "intelligent" Circuit breakers are used, which depends on favorable phase conditions of the current to be switched off switches off. If such a failure Circuit breaker what z. B. too long an arc duration can be recognized, the quick switch is ignited or triggered. This can increase the reliability of a Overcurrent protection with inexpensive "intelligent" Circuit breakers are significantly improved. Because of the very rare occurrence of such failure of the In this case the circuit breaker needs the circuit breaker to be designed for only a few switching operations. In the in most cases, a one-time function followed by Revision will be sufficient.

Preferably one used as a reserve switch Quick switch independent of the normal system protection system triggered, e.g. B. from a trigger device that from the local current flow is fed (not shown), d. H., independent of a trip signal for the circuit breaker.

If, for example, near a generator, due to asymmetry and thus missing zero crossings of the current to be switched off no timely interruption from very high ones Short-circuit currents can be achieved, then one Rapid switch with high arc voltage build-up a premature Force zero current crossing and thus timely Ensure power interruption.

The simply constructed quick switch according to the invention can also as a reclosable fuse element in High-voltage systems can be used because it is also a high rated current carrying capacity and high Has responsiveness. He can for the highest possible short-circuit current in the system to be protected be interpreted and, if necessary, after a Switch off half period.

The time delay between the arrival of a trigger signal and the beginning of the movement of the switching piston (2) can be due to fast electrical ignition and fast chemical Reaction kept much smaller than a half period become.

LIST OF DESIGNATIONS

1

Switch housing

2nd

Switching piston, bypass contact

2 '

Contact tube from 2

2a

Bridge from 2

3rd

Gas outlet opening, exhaust opening from 2

4, 4a - 4c

gas-generating charges, explosive charges

4 '

Ignition device for 4

5

Openings, explosion gas inlet openings

6

High pressure chamber

7

Low pressure chamber, piston chamber

8th

Exhaust chamber

9

Vent line in E2

10th

Electric arc

11

Finger contact, nominal current contact

12th

Compression spring

13

Sliding contact, compression spring

A

Axis of symmetry of 1, switch axis

a

Overlap distance from K1 'to K1

B

Arrow, direction of movement of 2 when opening the Quick switch

E1, E1 ', E1 "

1st electrode

E2

2. Electrode, hollow electrode

K1, K1 '

E1 erosion contact pins, arc extinguishing contacts

K2

Current contact element from 2

Claims (7)

Electric quick switch a) with a fixed 1st electrode (E1, E1 ', E1 ") and b) with a fixed second electrode (E2) spaced from it, c) furthermore with an electrically conductive bridging contact (2) which electrically connects the 1st electrode (E1, E1 ', E1 ") to the 2nd electrode (E2) when the quick switch is closed, d) furthermore with at least one gas-generating explosive charge (4, 4a - 4c) for extinguishing an arc (10), characterized, e) that the bridging contact is a switching piston (2) with a contact tube (2 '), f) which protrudes into a recess in the second electrode (E2) and is slidably movable therein, g) which contact tube (2 ') has at least one exhaust opening (3) on the circumference, h) which are closed by the second electrode (E2) when the quick switch is closed and i) is open to an exhaust chamber (8) in an open state of the quick switch. Electrical quick switch according to claim 1, characterized in a) that the 1st electrode (E1, E1 ', E1 ") has an erosion contact element (K1, K1'), which is in the closed state of the quick switch with a current contact element (K2) of the switching piston (2) in an electrically conductive sliding connection and b) that the switching piston (2) seals this erosion contact element (K1, K1 ') in a gas-tight manner with respect to a switch housing (1) of the high-speed switch. Electrical quick switch according to claim 1 or 2, characterized in that a) that the switching piston (2) on the one hand a high pressure chamber (6) and b) on the other hand delimits a piston chamber (7) which is connected to the exhaust chamber (8) via a vent line (9) in the second electrode (E2). Electrical quick switch according to one of the preceding Claims, characterized in that the at least one Explosive charge (4, 4a - 4c) in a recess in the 1st Electrode (E1, E1 ', E1 ") is mounted. Electrical quick switch according to claim 4, characterized characterized in that each explosive charge (4, 4a - 4c) over a separate feed channel with one or the High pressure chamber (6) communicates. Electrical quick switch according to one of the preceding Claims, characterized in that the 1st electrode (E1, E1 ', E1 ") when the quick switch is closed at least one nominal current contact (11) with the switching piston (2) is in an electrically conductive sliding connection. Use of an electrical quick switch after a of the preceding claims as an additional switch at least one circuit breaker, a trip of the Quick switch depending on a failure of the Circuit breaker is done.

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