JPH03205719A - Gas-blast circuit-breaker - Google Patents

Abstract

PURPOSE:To prolong equivalent shut-able arc time to at least 1.0 cycle and improve supply reliability while eliminating shutting disability even when multi- lightning happenes by connecting a plurality of shutting parts in series electrically and shifting the shortest shut-able arc time to at least 0.5 cycle. CONSTITUTION:A plurality of shutting parts 1, 2 are connected in series electrically and a shut-able arc time is shifted at least 0.5 cycle. The shut-able arc time width 4, 5 of the shutting parts 1, 2 are at least 0.5 cycle and the shortest shut-able arc time F of the shutting parts 2 is shifted 0.5 cycle from the shortest shut-able arc time E of the shutting parts 1 and thus practical shut-able arc time width becomes at least 1.0 cycle. Short-circuitted current owing to the first lightning is shut at the point C by the shutting part 1 but shutting is not able to be carried out at the C point due to multi-lightning and when current zero point moves to G point, shutting is not achieved by the shutting part 1 but by the shutting part 2. In this way, a circuit-breaker which is able to shut even the case of multi-lightning is obtained and supply reliability is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a gas circuit breaker, and particularly to a structure that is effective in widening the arc time width that can be interrupted.

[Conventional technology]

In current power systems, gas circuit breakers that spray sulfur hexafluoride gas to shut off the circuits are the mainstream, and are generally used as high-voltage, large-capacity circuit breakers that have a simple circuit structure and excellent disconnection performance. A Patsufa type gas circuit breaker is used.

[Problem to be solved by the invention]

The above-mentioned conventional technology does not consider the case where multiple lightning strikes occur on the power transmission line, and there is a problem in terms of interrupting performance. In other words, a patchwork circuit breaker can handle a single large lightning strike, but it becomes unable to shut off when multiple lightning strikes occur several times in a very short period of time. .

Figure 7 shows the pressure rise characteristics of the puffer type shutoff section.

The puffer pressure increases as the cutoff stroke moves, but the pressure that can cut off the short circuit current requires, for example, the AB line or higher. If the current reaches a zero point like point C when the current is above this line, the interruption will be successful, but if the arc time increases due to multiple lightning strikes and the current reaches zero point at point D, the interruption will become impossible.

Generally, the arc time width that can be interrupted by a puffer type interrupter is:
0.5 cycles (10ms at 50Hz, 8 at 60Hz
．． 3ms), so if the circuit breaker trips or there is lightning, the arcing time will be 10ms or more, making it impossible to deal with it.

The purpose of the present invention is to solve the above problems,
The aim is to improve supply reliability without being unable to shut down even when multiple lightning strikes occur.

[Means to solve the problem]

In order to solve the above problem, the present invention electrically connects a plurality of interrupting parts in series, and sets the fastest interruptible arc time to 0.
It is shifted by more than 5 cycles.

[Effect]

By shifting the fastest interruptible arc times of multiple interrupting sections by 0.5 cycles or more, the equivalent interruptible arc time extends to 1.0 cycles or more, so even if multiple lightning strikes occur in a short period of time, it will not work in the later stages. It can be shut off at the shut off section. In addition, in the event of a delayed lightning strike, the gaps between the poles of the multiple blocking sections are open, making it capable of withstanding lightning impulses.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. Two cutoff sections 1 and 2 are electrically connected in series, and a control device 3 issues a cutoff command for each cutoff section. The interruptible arc time widths 4 and 5 of the interrupters 1 and 2 are at least 0.5 cycles or more. The fastest breaking arc time F of the breaking part 2 is 0 from the fastest breaking arc time E of the breaking part work.
．． 5 cycles shifted. As a result, the actual interruption arc time width becomes 1.0 cycles or more.

The short-circuit current caused by the first lightning strike is interrupted at point C by interrupter 1, but if multiple lightning strikes cause it to become uninterruptible at point C and the current zero point becomes point G, interrupter l cannot interrupt the short-circuit current. First, the shutoff section 2 shuts off. As described above, according to this embodiment, it is possible to provide a circuit breaker that can interrupt even multiple lightning strikes, thereby improving supply reliability.

FIGS. 3 and 4 show further variations of the present invention. In areas where there is a high probability of lightning strikes, such as mountainous areas, lightning may strike several times over a long period of several tens of milliseconds. Therefore, this is a case where the four interrupting parts 1, 2, 6.7 are electrically connected in series. The interruptible arc time width of each interrupting section is 4,
5, 8.9, the fastest arc time that can be interrupted is 0.5
It's delayed by cycles. As a result, the effective arc time width that can be interrupted becomes 2.0 cycles or more. No.l
The configurations shown in Fig. 3 and Fig. 3 are as follows.
, or when the cut-off part 7 is cut off, the voltage withstands the lightning impulse.

FIG. 5 shows an example in which both movable parts of two puffer-type cut-off parts 10.11 are driven by the same insulated operating rod 15. The stroke characteristics of the blocking portion 10 and the blocking portion l1 are changed as shown in S1 and 82, as shown in FIG. That is, by opening the circuit breaker 11 with a delay of 0.5 cycles or more, even if the circuit breaker 10 becomes unable to shut off due to multiple lightning strikes, the circuit breaker 11 can perform the circuit.

The configuration of FIG. 5 will be explained. A sealed container (not shown) is filled with SFe gas at a predetermined pressure. A bracket 13 is coupled to an insulating support cylinder 12 fixed to the inner surface of the sealed container, and a link mechanism 1 is attached to this bracket 13.
One end of the link mechanism 14, on which one end of the link mechanism 14 is supported, is connected to the insulated operating rod 15, and the output side has two ends, one of which is connected to the movable contact 16 of the interrupting part 10,
The other end is connected to the movable contact 7 of the blocking section 11.

A cylinder l8 is connected to the movable contact 16, and an insulating nozzle 19 is attached to surround the movable contact 16. Piston 20 coupled to bracket 13
The cylinder l8 is in a sliding relationship, and the two constitute a compression device. This compression device is
The gas in l is compressed, and this gas is guided through an insulating nozzle l9 to spray against the arc generated between the fixed contact 26 and the movable contact 16. Main contacts 24 and 25 for main energization are configured electrically in parallel with the contacts of the cutoff section. The blocking section 11 also has the same structure and shape as the blocking section 10. The cutoff part 10 and the cutoff part ↓l are electrically connected in series via the bracket l3, and voltage dividing impedances 22 and 23 are electrically connected in parallel with each cutoff part.

The structure of the link mechanism l4 is different between the blocking parts 10 and 11, and the latter structure will be explained below.

The other end of the link 30, one end of which is fixed to the insulated operating rod 15, is guided within an ellipse 31 formed along the direction of movement of the movable contact 17. At a position approximately half of the total axial length of this link 30, there is a link 3 having an axial length approximately half of this total axial length.
The other end of the link 32 is rotatably supported by the bracket 13. With this configuration, the horizontal movement of the insulated operating rod 15 in the drawing is converted into vertical movement of the other end of the link 30 along the inside of the oval hole 31.

One end of a link 34 is connected to the inner end of the bracket 13 of the shaft 33 of the movable contactor 17, and the other end of a link 35 whose one end is rotatably supported on the bracket 13 is connected to the other end of the link 34. ing.

One end of a link 36 is connected to the connection point of the links 34 and 35, and the other end of this link 36 is connected to the other end of the link 30.

Therefore, when the other end of the link 30 moves through the oval hole 31 in the circuit direction upward in the drawing, the link 34.
The connecting part between 35 and 35 is moved somewhat downward in the drawing in the closing direction
Eventually, the movable contact 17 is driven upward in the opening direction, and the operating characteristics of the movable contact 17 become as shown in the stroke characteristic S2 in FIG. 6. If it is not desired for the movable contactor 17 to move once in the closing direction, a general method of delaying movement by forming a connecting portion using an elliptical hole in the middle of the link can be adopted. According to such an embodiment, the arc time width that can be interrupted is expanded by the common term between the interrupting parts 10 and l1, so even if multiple lightning strikes occur, the interrupting part 1 that operates later
It can be shut off by construction.

In FIG. 5, the cut-off parts 10, 11 are constructed of puffer-type cut-off parts, but the same effect as shown in FIG. 5 can be obtained even if a cut-off part of other structure such as a self-acting cut-off part is used.

〔Effect of the invention〕

According to the present invention, by electrically connecting a plurality of interrupting parts in series and shifting the interruptable arc time by 0.5 cycles or more, it is possible to equivalently expand the interruptable arc time, so multiple lightning strikes can occur in a short time. Even if a problem occurs in the system, it can be shut off by a shutoff unit that operates at a later stage.

[Brief explanation of drawings]

FIG. 1 is a block diagram of one embodiment of the present invention, and FIG. 2 is a block diagram of an embodiment of the present invention.
Fig. 3 is a block diagram of another embodiment of the present invention, Fig. 4 is a time relation diagram of Fig. 3, and Fig. 5 is a longitudinal section of a gas circuit breaker according to an embodiment of the present invention. 6 is a stroke explanatory diagram of FIG. 5, and FIG. 7 is a principle diagram of a conventional example. 1, 2... Cutoff unit, 3... Cutoff command control device, 4,
5... Arc time width that can be interrupted. 1 Figure 2 Figure 2 Figure 3 Figure 4 Figure 5 Ginma →

Claims (1)

[Scope of Claims] 1. A plurality of gas circuit breakers are electrically connected in series and arranged, characterized in that the fastest possible shutdown time of at least one of the gas circuit breakers is shifted by 0.5 cycles or more. gas circuit breaker. 2. A gas cutoff in which a plurality of gas cutoff parts are electrically connected and arranged in series, characterized in that the opening time of at least one of the gas cutoff parts is delayed by 0.5 cycles or more. vessel.