DE2319836A1 - CIRCUIT BREAKER - Google Patents

Description

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April 18

HITACHI. LTDo. Tokyo (Japan)

Circuit breaker

The invention relates to a circuit breaker, in particular to a circuit breaker of the gas buffer type with a multiple switching part, which is derived from the electromotive Force is driven.

In recent times, as the demand for electrical power increases, the transmission lines carry higher and higher Voltages and also stronger currents to enable high-capacity energy transfer. A circuit breaker, which is used as a protective device for such a high-capacity transmission line must be such be such that with it an electric current

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high voltage and high current can be switched and interrupted.

For this purpose, a circuit breaker is used as such, the one arc generated between the contactors by blowing an arc-quenching insulating medium with good erasing properties, such as B. SF ^ gas, against extinguishes the arc. However, this type of circuit breaker is also high voltage in terms of switching and strong current only limited usable in the presence of only one switching unit, and therefore recently the circuit breaker is provided with a multiple switching part, which consists of a plurality of series-connected Switching units consists.

On the other hand, a gas buffer type circuit breaker requires a strong actuating or driving force « This is because the gas buffer circuit breaker an arc extinguishing gas essentially at the same time as the switching or disconnecting process or the movement of the contactor for the purpose of blowing the compressed high pressure arc extinguishing gas against one generated between the contactors Arc is compressed to extinguish the arc. There is also the compression path of the compressor to compress the arc extinguishing gas is significant the switching path of the contactor is also long.

If the gas buffer circuit breaker has multiple switching units has that operated or driven by a drive piston at the same time and together according to the previous type must be driven, which in turn is driven by compressed air as the working medium, the

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the driving force will be all the stronger. To overcome this difficulty, the switching units can be in a number can be subdivided into groups «If, however, separate groups are to be operated by separate actuators, you do not expect a good and stable switching behavior, because the drive processes in the individual groups are not would be balanced »

There is still a type of circuit breaker in which the electromagnetic energy of the circuit breaker is to be interrupted Current is used as the driving force »This type of circuit breaker is constructed in such a way that the Current at the time of switching in the primary coil is diverted to an electromagnetic repulsion or Attraction between the primary coil and the electromagnetic secondary inductive unit coupled with it to produce «As the electromagnetic through this Drive device generated electromagnetic force proportional to the square of the interrupted Is current, the switching unit is safely driven with every strong current »

However, the circuit breaker has one electromagnetic drive device as explained above is provided for each switching unit, complicated in structure, making it difficult to Adjust the mechanism so that the individual switching units work evenly »

For this reason, it is difficult to manufacture a circuit breaker with good uniform switching characteristics.

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The invention is based on the object of a circuit breaker to create with several switching units of the gas buffer type, which is characterized by a low external driving force can switch. The circuit breaker should also in its entire structure and also in terms of The structure of each switching unit can be simplified by using a single electromagnetic drive mechanism for the different switching units is provided jointly »

The subject of the invention, with which this object is achieved, is a circuit breaker which is identified by at least two switching units electrically connected in series, each with at least one pair of one arc-inducing Interrupting or disconnecting effecting contactors, a compressor for compressing a Arc extinguishing gas and a nozzle for blowing the through the Compressor of highly compressed arc extinguishing gas against the arc,

one consisting of a primary coil and a short-circuit ring or coil electromagnetically coupled therewith electromagnetic drive,

one that can be actuated in accordance with an interrupt command Current diverting device for diverting a current to be interrupted into the electromagnetic drive and

Connectors for electrically isolated connection of the electromagnetic drive with moving parts of the switching units to move these moving parts «

With this circuit breaker everyone can

switch currents, no matter how strong, with a small external actuation force «

The invention is explained in more detail with reference to the exemplary embodiments illustrated in the drawing; in this demonstrate;

F ± g _t 1 a sectional view of an embodiment of the circuit breaker according to the invention;

Flg. 2 shows a cross section along the line H-II in FIG. 1;

Fig. 3 shows an equivalent circuit of the circuit breaker of Fig. 1;

Fig. K is a sectional view of part of another embodiment of the circuit breaker according to the invention; and

Fig. 5 is a sectional view of a further embodiment of the circuit breaker according to the invention.

According to FIG. 1, two switching units Ta and 1b are electrically connected in series. Each of the switching units 1a and 1b consists of a fixed contactor 2, a movable contactor 3 facing the fixed contactor 2, a compressor consisting of a buffer cylinder k and a buffer piston 5 and defining a buffer chamber 6 therein, and an insulating nozzle 7 which contains an arc-extinguishing gas, such as z. B. Sulfur hexafluorid (SF ^) gas

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against an arc generated between the fixed contactor 2 and the movable contactor 3 blows _s The movable contactor 3 »the buffer cylinder k and the insulating nozzle 7 are interconnected. The buffer piston 5 of the switching unit Ta and the fixed contactor 2 of the switching unit 1b are carried by the same fixed support 8. The movable contactor 3 and a supporting conductive tube 9 of the buffer piston 5 are in electrical contact with one another via a current collector 10.

An operating rod 11, which is connected to a not shown external actuator is connected, has an axial part 11a, which is a driving force to a discharge device 12, which will be described, transmits and slidably passes through a carrier 13 which is connected to the moving parts of the switching units 1a and 1b, and the rod 11 also has stops 11b and 11c, the freedom of movement of the carrier 13 limit. For pushing the carrier 13 in the shown In the closed state downwards against the stop lic, a spring 14 is provided.

The current deriving device 12 consists of a hollow fixed contactor 15 »a fixed contactor 15 opposite movable contactor 16, a compressor with a movable buffer piston 17 and a solid buffer cylinder 18, which together have a Form buffer chamber 19, and an insulating nozzle 21, the arc extinguishing gas, which in the buffer chamber 19 at high pressure is compressed against a generated between the fixed contactor 15 and the movable contactor 16

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Arc blows. The movable contactor 16 is with the actuating rod 11 connected, the movable contactor 16, the movable buffer piston 17 and the Isolating nozzle 21 through the actuating rod 11 as a composite are operable. The movable contactor 16 makes contact electrically a current collector 22 provided at one end portion of the fixed buffer cylinder 18,

An electromagnetic drive 23 surrounds the fixed contactor 15. The electromagnetic drive 23 has a primary coil 2k, into which the current to be interrupted is diverted by the discharge device 12, and a short-circuit ring 25 which is electromagnetically coupled to the primary coil 2k , so that an induction current in the short-circuit ring 25 is inducible _3, which makes it repulsive to the primary coil 2k = the short-circuit ring 25 can also be a short-circuit coil which has a short-circuited winding =.

The primary coil 2k is z. B. an integrally formed unit and attached to a fixed support 26, to which the buffer piston 5 of the switching unit 1b and the fixed contactor 15 of the discharge device 12 are attached. The short-circuit ring 25 is connected to connecting rods 28 which are mechanically connected to metal holders 27 attached to the buffer cylinders 4 of the switching units 1a and 1b and which actuate the moving parts of the switching units 1a and 1b.

The primary coil 2k and the short-circuit ring 25 are arranged coaxially and each have certain axial lengths, so that in the state shown, the primary coil 2k

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is inserted into the short-circuit ring 25. With this arrangement, even if the short-circuit ring 25 moves, a certain electromagnetic force can be developed over a long distance. A conductor 34 is seated at the bottom of the primary coil 2k.

The solid parts of the switching units 1a and Ib, and the solid part of the drain 12 are insulative support rods 29 held Xm each be a fixed support 31 'carrying the fixed contactor 2 of the switching unit 1a and is formed at its end portion to a terminal 30 _s of the fixed carrier 8 ₉ which is provided between the switching unit 1a and the switching unit 1b, the fixed carrier 26 which is provided between the switching unit 1b and the discharge device 12, and a fixed carrier 33 »which carries the fixed buffer cylinder 18 of the discharge device 12 and is formed at its end part to a connection 32, carried by the insulating support rods 29 »

In Fig. 2, which shows a cross section along the line H-II in Fig. 1, the three insulating support rods 29 carry the fixed support 8, and the connecting rods 28, which are connected to the short-circuit ring 25 of the electromagnetic drive 23, are alternately with the insulating support rods 29 arranged offset. The connecting rods 28 are attached to the metal brackets 27, which in turn are attached to the buffer cylinders h \ as described above.

The current path in the closed state shown in FIG. 1 is! Connection 30 - solid support 31 - solid

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ORiGSNAL INSPECTED

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Contactor 2 - movable contactor 3 - current collector 10 - supporting conductive tube 9 - fixed support 8 more solid Contactor 2 - moving contactor 3 current collector 10 - carrying conductive tube 9 - more solid Carrier 26 - fixed contactor 15 - movable contactor 16 - current collector 22 - fixed buffer cylinder 18 - fixed support 33 - connection 32

If the through the fixed contactor 15 and the movable contactor 16 of the discharge device 12 If the current flowing is interrupted in the initial stage of shutdown, the result is the current path of a solid carrier 26 - primary coil 24 - conductor 34 - fixed buffer cylinder 18 «

FIG. 3 is an equivalent circuit diagram of the circuit breaker according to FIG. 1. A series connection of the switching units 1a and Ib are in series with a parallel connection the discharge device 12 and the electromagnetic drive 23 connected. When the discharge device 12 is closed is, only a little current flows through the electromagnetic drive 23 »because the resistance of the discharge device is chosen so that it is very small in comparison with the electromagnetic drive 23.

In a switching process in which the operating rod 11 pushes downward in FIG. 1 by an external drive device (not shown), becomes the movable one Part of the discharge device 12 pushed down so that the contact between the fixed contactor 15 and the movable contactor 16 is interrupted, so that the movable buffer piston 17, which is formed with the movable contactor 16 into an integral unit is, an arc extinguishing gas in the buffer chamber 19 grain

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ORIGINAL JNSPECTED

- to -

and this is blown against an arc generated between the fixed contactor 15 and the movable contactor 16. As a result, the arc voltage between the fixed contactor 15 and the movable contactor 16. When the arc voltage becomes higher than the voltage drop of the circuit containing the primary coil 2k , the arc is extinguished by blowing with the high pressure arc extinguishing gas before the current in the main circuit goes to zero reached so that the current is diverted into the circuit with the primary coil 2k »

Since the impedance of the primary coil is around 10 /, the voltage is only around 200 - 300 V for switching 50 kA. Consequently, even if the compressive action on the arc extinguishing gas occurring simultaneously with the contactor breaking operation is small to generate a highly compressed arc extinguishing gas, the arc generated between the fixed contactor 15 and the movable contactor 16 can be extinguished sufficiently.

At this time, only the bracket 13 slides on the axial part 11 a of the operating rod 11.

When the current is diverted through the diverter device 12 into the circuit with the primary coil 2k , a magnetic flux is generated around the primary coil 24 by the current to be interrupted. The magnetic flux induces an induction current in the short-circuit ring 25 »which is electromagnetically coupled to the primary coil 2k , whereby an electromagnetic

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Repulsive force between the primary coil 2k and the short-circuit ring 25 arises, so that the short-circuit ring 25 is driven downward in FIG .

By moving the connecting rods 28, the buffer cylinders k of the switching units 1a and 1b are driven to cause an interruption or disconnection process between the fixed contactor 2 and the movable contactor 3, which on the other hand compresses the arc-extinguishing gas in the buffer chamber 6 of the compressor. A slider 35 'suitable for wiping is provided at the upper end portion of each movable contactor 3 so that an arc can be generated between the fixed contactor 2 and the movable contactor 3 in the state where the arc extinguishing gas in the buffer chamber 6 passes the compressor is compressed to a certain pressure. The arc-extinguishing gas, which is thereby put under high pressure, is blown against the arc generated between the fixed contactor 2 and the movable contactor 3 until it is extinguished, whereby the interruption or disconnection of the circuit breaker is completedo

The closing or switching on process will now be described. If the operating rod 11 by a not shown outer actuating device is pushed up in the drawing, drives the actuating rod 1 1 not only the movable contactor 16 of the

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guide device 12, but also the connecting rods 28 connected to the carrier 13 upwards, so that the moving parts of the switching units 1a and 1b are shifted in the closing or switching-on direction, since the carrier 13 is pressed against the stop 11c the fixed contactor 15 and the movable contactor 16 are turned on first, and then the fixed contactors 2 and the movable contactors 3 of the switching units 1a and 1b are closed or turned on. If the wiping path of the sliding piece 36 of the diverting device 12 is made larger than the wiping path of the sliding pieces 35 of the switching units 1a and 1b ₉ , the switching on of the diverting device 12 is achieved earlier than that of the switching units 1a and 1b,

With this measure, the discharge device 12 never causes an earlier discharge at the time of switching on As a result, there becomes a phenomenon that an electromagnetic force occurs between the primary coil 24 and the short-circuit ring 25 at the time of power-on due to the flowing through the primary coil 24 due to premature discharge Current occurs, prevented, so that the switch-on process is even and smooth.

Fig. 4 is a modification of the discharge device 12 according to Fig. 1. Substantially in the middle part of a solid one Buffer cylinder 40 is a second movable buffer piston 42 is provided by a spring 41 in the the direction of movement of the movable buffer piston 17 at the time of the interruption is pressed opposite the direction will. This arrangement reduces the volume of the buffer chamber 43.

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In operation, due to the downward movement of the actuating rod 11, the movable contactor l6 causes a Interrupting movement away from the fixed contactor 15, and at the same time compresses the movable buffer piston 17 an arc extinguishing gas in the buffer chamber 43 » since the volume of the buffer chamber 43 is smaller than that of the Buffer chamber 19 in Fig. 1 is made, the arc extinguishing gas in the buffer chamber 43 at a higher speed a smaller stroke of the movable contactor 16 compressed. The second movable buffer piston 42 pulls back, the pressure in the buffer chamber 43 increasing is kept at a high value because it is by the spring 4i is pressed so that the arc generated between the contactors 15 and 16 is quickly extinguished and at the same time the time required to interrupt the entire circuit breaker is reduced «

Fig. 5 shows a further embodiment of the invention. Although only three switching units 51a, 51b and 51c shown therein, any desired number of switch units can be added above switch unit 51c. Between the switching unit 51a and the switching unit 51b are a diverter 52 and an electromagnetic one Drive 53 is provided. Each of the switching units 51a to 51c consists of a fixed contactor 54, a movable contactor 55 »one consisting of a buffer cylinder 56 and a buffer piston 57, together a compressor defining a buffer chamber 58, and a funnel-shaped insulating nozzle 78 »die an arc extinguishing gas from the buffer chamber 58 to an intermediate the contactors 54 and 55 directs generated arc. The movable contactor 55 consists of a

Main contactor 55a and an arc contactor 55t> » that creates an arc.

The discharge device 52 consists of a fixed contactor 59 and a movable contactor 60. The fixed contactor 59 is provided on its inner wall surface with an insulating layer 62 except for the part where a current collector 6i is provided. The movable contactor 6.0. is provided with an insulating layer 63 at its upper end part at a certain distance from the part facing the current collector 01 in the closed state. By means of this arrangement, an arc is directed into the insulating layers 62 and 63 to effect a brief arc extinction. Such a discharge device 52 is of a simpler construction than that in FIGS. 1 and 4. "

The electromagnetic drive 53 consists of a primary coil 64 and a short-circuit ring 65, which is thus electromagnetically coupled in a manner similar to that in FIG. 1, and will therefore not be described again in detail. An operating rod 66 connected to an external drive device (not shown) has an axial part 66a which slidably passes through a carrier 68, which is supported by connecting rods 77 with holders 67 which are attached to the buffer cylinders 56 of the switching units 51a to 51c, and also to the short-circuit ring 6 ^ is connected, and the actuating rod 66 further has a stop 66b for limiting the movement of the carrier. The movable contactor 60 of the discharge device 52 is connected to the actuating rod 66 by means of a connecting rod 69.

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Fixed supports 70 that hold the fixed parts of the switch units 51a to 51c are supported by at least one supporting insulating rod 71 held *

The current path according to this exemplary embodiment is switching unit 51c - switching unit 51t> - discharge device 52 - switching unit 51a - connection 72, and in each of the switching units 51a to 51c the current path runs fixed support 70 - fixed contactor ^ k - main contactor 55a - buffer cylinder 56 - current collector 73 Buffer piston 57 - piston carrier Ik - fixed carrier 70. The current path in the discharge device 52 is ι fixed carrier 70 - fixed contactor 59 - current collector 6l movable contactor 60 - current collector 75 - fixed carrier 70.

When switching off or interrupting operation, when the operating rod 66 is pushed down, the movable contactor 60 of the discharge device 52 to interrupt the line with the current collector 61 and to drive an arc into the insulating layers 62 and 63 downwards, so that a brief arc erasure results. The current to be interrupted, which previously flowed through the discharge device 52, is diverted into the fixed support 70, the primary coil 6k - a conductor 76 - the fixed support 70. The short-circuit ring 65 is operated by the electromagnetic repulsive force induced by the current flowing through the primary coil 64 to drive the moving parts of the switching units 51a to 51c, whereby the fixed contactor 5k and the main contactor 55a are separated so that an arc between the fixed contactor $ k and the arc

contactor 55b. is generated. At the same time an arc extinguishing gas is used compressed in the buffer karamer 58 to high pressure and blown through the insulating nozzle 78 against the arc to extinguish it and the interruption process to be completed "

In the closing or switch-on mode, when the operating rod 66 is pushed up, the diverting device 52 and the switching units 51a to 51c are driven in the closing direction, the diverting device 52 being closed first and then the switching units 51a to 51c. This is because the wiping path of the discharge device 52 is made larger than the wiping path of the switching units 51a to 51c, thereby preventing a current from flowing through the electromagnetic drive 53, which is otherwise caused by the premature discharge in the switching units 51a to 51c at closing time occurs, so that as a result of this arrangement, the closing process proceeds smoothly and evenly.

It should also be pointed out that in all of the exemplary embodiments explained above, the switching units, the discharge device and the electromagnetic drive are or are introduced into a vessel that is filled with an arc extinguishing gas with good electrical insulating properties.

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Claims (10)

1.) lei Patent claims Circuit breaker, characterized by at least two electrically connected in series Switching units (la, 1b; 51a, 51b, 51c) each with at least a pair of contactors (2, 3; 54, 55) causing an arc-inducing interruption or disconnection a compressor (4, 5 »6; 56, 57» 58) for compressing a Arc extinguishing gas and a nozzle (7; 78) for blowing the arc extinguishing gas highly compressed by the compressor against the arc; one of a primary coil (24; 64) and an electromagnetic short-circuit ring (25; 65) or coil that is electromagnetically coupled therewith Drive (23; 53) 5 a current discharge device which can be actuated in accordance with an interrupt command (12; 52) for diverting a current to be interrupted in the electromagnetic drive (23; 53); and connectors (28, 27; 77, 67) for electrically isolated connection of the electromagnetic drive (23; 53) with the movable one Parts (4; 56) of the switching units (la, 1b; 51a » 51b, 51c) to move these moving parts. 2. Circuit breaker according to claim 1, characterized in that that the primary coil (24; 64) and the (the) short-circuit ring (25; 65) or coil of the electromagnetic Drive (23; 53) are concentric cylinders, each of which has a certain axial length, and that the Primary coil and the (the) short-circuit ring or coil each other overlap at a time during the relative movement. 3. Circuit breaker according to claim 1, characterized 409845 / G46b - 18 - indicates that the primary coil (2k; 64) of the electromagnetic drive (23; 53) is attached to a fixed support (26; 70) and the short-circuit ring (25; 65) or coil of the electromagnetic drive with the connecting pieces ( 28; 77) is connected. 4. Circuit breaker according to claim 1, characterized in that that the diverting device (12) has at least one pair of contactors (15> 16) which have an arc-inducing Effect separation, a compressor (z. B. 17 »18, 19) for compressing an arc extinguishing gas and a Having a nozzle (21) for blowing the arc-extinguishing gas pressurized by the compressor against the arc. 5 «circuit breaker according to claim 4, characterized in that that the compressor has a first piston (i7) »one separated by a certain distance from the first piston and by a compression spring (4i) in the opposite direction to the actuation direction of the first piston Direction pressed second piston (42) and a cylinder (4o) which is connected to one of the two pistons or is provided independently. 6. Circuit breaker according to claim 1, characterized in that that it has an actuating rod (11; 66) which is used for joint actuation of the discharge device (12; 52) and the switching units (la, 1b; 51a, 51b, 5 ^ c) and has a connecting part that is used to actuate the discharge device prior to actuation of the switching units during the interruption process. 409845/046 7. Circuit breaker according to claim 6, characterized in that the connecting part has a carrier (13; 68) mechanically connected to the switching units, a carrier (13> 68) slidably penetrating axial part ("Ma; 66a) of the actuating rod (11, 66) and a stop (lib; 66b) which is attached to the actuating rod for the purpose of restricting the displacement of the carrier (13; 68) to a certain length » Circuit breaker according to Claim 1, characterized in that the switching _{units (e.g. 5} 1a, 1b), the discharge device (e.g. 12) and the electromagnetic drive (e.g. 23) are arranged coaxially and can be operated in the same direction are. 9. Circuit breaker according to claim 8, characterized in that that the discharge device (z. B, 12) closer to the actuating rod (ii) than that of this actuating rod next switching unit (ib) is arranged. 10. Circuit breaker according to claim 1, characterized in that that the diverting device (52) has at least one pair of contactors (59, 6o), of which one contactor (6o) is inserted into a hollow part of the other contactor (59) with the outer wall surface of the one contactor (60) and the inner wall surface of the other contactor (59) in such a way with insulating layers (63 or 62) are provided that at the time of switching off the insulating layers with each other face the smallest possible gap into which an arc to be extinguished can be pressed. 4Q9845 / 046b 11 «circuit breaker according to claim 1, characterized in that the wiping path between the contactors (15, 16; 59, 60) of the discharge device (12; 52) is greater than the wiping path between the contactors (2, 3; 5 ^ ₉ 55) each Switching unit (la, 1b; 51a, 5ib, 51c) is » J / Blank page