JPH0449731B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power sheath disconnection device, and particularly to one in which a puffer type sheath disconnection section and a vacuum sheath disconnection section are connected in series.

The short-circuit capacity of electric power systems continues to increase as demand for electricity increases and supply sources become more concentrated and unevenly distributed, and UHV and DC transmission with a rated voltage of 1000 kV are being planned. Accordingly, the responsibility placed on power shield disconnectors is to increase the shield disconnection capacity and increase the voltage. In recent years, buffer-type gas shields and circuit breakers filled with SF ₆ gas, which has excellent insulation and arc-extinguishing properties, have become mainstream as high-voltage, large-capacity circuit breakers. Due to its excellent arc extinguishing properties, the arc breaking capacity per unit has reached 300kV50kV, and the combination of this unit has reached 550kV63kA2.
Single-point disconnection, 1100kV63kA four-point disconnection is also possible.

However, the buffer type gas shield disconnector's buffer characteristics are affected by the current change rate at the zero current point (di/dt) and the rate of increase in the restart voltage immediately after the current shield breaks (dv/dt), and currently, , di/dt is 30~
It is estimated that the maximum per unit is 40A/μs and dv/dt of 10 to 15kV/μs, and depending on the combination, performance limits appear below these values. In particular, when used for direct current or disconnection, it is assumed that di/dt may exceed 50A/μs, and if dv/dt is large, the current will drop from several kV to several tens of kV within a few microseconds after the current is interrupted. At a voltage of , there is a high percentage of thermal breakdown and failure of thermal breakdown, and the limit of thermal breakdown characteristics is determined by this thermal breakdown.

In order to improve this thermal breakdown characteristic, in puffer-type gas shield disconnectors, a capacitor is often inserted in parallel to the shield section to soften the dv/dt. However, inserting a capacitor in parallel to the shear break is a big disadvantage in terms of insulation reliability, so it is best to eliminate the capacitor or, even if it is provided, to minimize the capacitance (for example, by cutting it at multiple points). (capacity to improve the voltage sharing ratio in disconnectors) is desired.

On the other hand, vacuum cutters have high di/dt and dv/dt
It has performance that can withstand from 50A/μs to rarely
It can withstand di/dt of 150~200A/μs, and
It is said to be able to withstand dv/dt of 10kV/μs.
However, with the current vacuum shield disconnection technology, the occurrence of restriking cannot be avoided due to structural reasons, making it difficult to realize an ultra-high pressure vacuum shutoff.

Therefore, we decided to use a patchworker type gas disconnector and a high di/
A vacuum breaker which exhibits sufficient insulation recovery characteristics against dt is connected in series to make use of the characteristics of each. An example is shown in FIG. This crinkling device has two containers 2 and 3 that are airtightly partitioned by an insulating spacer 1, and a puffer-type crinkle section 4 is provided in one container 2 and a vacuum is provided in the other container 3. A sheath section 5 is installed. The puffer-shaped sheath section 4 includes a fixed contact 6, a movable contact 7, a puffer cylinder 8, an insulating nozzle 9, a piston 10, a piston support fitting 11, and the like. Piston support fitting 1
1 is supported on an insulating support 12 and connected to the center conductor 13 of the bushing. The movable contactor 7 is operated from the outside via an insulated operating rod 14, a lever 15, etc. Further, the vacuum shield section 5 is composed of a fixed contact 16, a movable contact 17, a vacuum container 18, and the like. The vacuum container 18 is composed of an insulating cylinder 19, a fixed contact side terminal 20, a movable contact side terminal 21, a bellows 22, and the like. The bellows 22 is attached so as to protrude inside the vacuum container 18. The movable contact side terminal 21 is supported by an insulating support 23 and connected to a center conductor 24 of the bushing. The movable contactor 17 is operated from the outside via an insulated operating rod 25 and a lever 26.

The powder mold sheath section 4 and the vacuum sheath section 5 are
The respective fixed contacts 6 and 16 are connected in series so as to be directly connected. The containers 2 and 3 are each filled with SF ₆ gas, and the gas pressure in the container 3 is lower than that in the container 2. This is to protect the bellows 22 of the vacuum shield section 5. In this sheath disconnection device, most of the initial part of the recovery voltage after the current sheath interruption is borne by the vacuum sheath breaker 5, and the subsequent increase in voltage is borne by the puffer type sheath breaker 4. It is designed to do so. For this purpose, a non-linear resistor 27 is connected in parallel to the vacuum shield section 5, and a capacitor 28 is connected in parallel to the puff type shield section 4. In addition, in order to prevent the insulating spacer 1 from being damaged by the high temperature gas released from the puffer mold sheath section 4, an insulating guide is placed around the fixed contact 6 of the puffer mold sheath section 4. 29 are provided.

With the above configuration, high di/dt and dv/
It is possible to create an ultra-high pressure shear cutting device that can withstand dt. However, in the above-mentioned disconnection device, when it is in the closed state, current flows through the contacts of the puffer-type shield and the vacuum shield, and the contact area of these contact parts Since it is not possible to increase the current level, the current level is limited to about 3000A at most. Therefore, the rated current is
In case of 4000A, 8000A, or even 12000A,
It is conceivable to separately provide current-carrying contacts in each of the puffer-type sheath section and the vacuum sheath section.
However, apart from the patchwork and fractures,
Since the vacuum shield section has a short stroke and the contacts contact each other by butt, when the vacuum shield section is disconnected, it is necessary to open it before the contact (for arc extinguishing) of the vacuum shield section. Providing current-carrying contacts that need to be spaced apart has the disadvantage that the structure becomes extremely complicated. Therefore, it has been difficult to increase the applied current with the above-mentioned disconnection and disconnection devices.

In addition, recently, a structure in which a puffer-type shield section and a vacuum shield section are connected in series, and each is provided with an energizing contact, has been proposed. An example is shown in FIG. This shredder also includes an insulating spacer 1, a container 2 on the high gas pressure side, a container 3 on the low gas pressure side,
It is provided with a puffer mold sheath section 4 and a vacuum sheath section 5. In this device, the fixed contacts 6 and 16 of the puffer type sheath section 4 and the vacuum sheath section 5 are arranged on the outside, and the movable contacts 7 and 17 are arranged on the inside, respectively. An insulated operating rod 30 for operation is arranged in the center. In other words, the first
The arrangement is reversed from that shown.

A fixed-side energizing contact 31 is provided on the fixed contact 6 side of the puffer-shaped sheath section 4, and a movable-side energizing contact 32 is provided on the buffer cylinder 8. Further, a fixed-side current-carrying contact 33 is provided on the fixed contact 16 side of the vacuum shield section 5, and a movable-side current-carrying contact 34 is provided on the movable contact 17 side. The movable side energizing contact 34 on the side of the vacuum shield section 5 is connected to the movable contact 1 of the vacuum shield section 5.
It is driven by a wiping device 35 which has a larger stroke than the vacuum sheath section 5 and which is designed to separate the sheath faster than the vacuum sheath section 5 when the sheath is broken. Therefore, in this shredder cutting device, when in the closed state, the bushing center conductor 13 - the support metal fitting 36 - the fixed side energizing contact 31 - the movable side energizing contact 32
- Buffer cylinder 8 - Slide contact 37 - Intermediate structure 38 - Slide contact 39 - Movable side energizing contact 34 - Fixed side energizing contact 33 - Support fitting 40 - Most of the paths of the bushing center conductor 24 An energizing current will flow.

Here, when an overcurrent detection device (not shown) detects an overcurrent flowing through the circuit and a tripping signal is transmitted to the disconnection device, a drive (not shown) using the repulsive force of a spring, high pressure air, hydraulic pressure, etc. The insulating operating rod 30 is driven downward in the figure by the force generating mechanism. This movement is transmitted to the movable contact 7 and the wipe device 35 by the link mechanism, and in the case of the puffer type sheath section 4 side, the movable contact 7, puffer cylinder 8, and movable side energizing contact 32 are integrated. The wiping device 35 and the movable energizing contact 34 are driven to the left in the figure as a unit on the vacuum shield section 5 side.

At this time, on the side of the puffer-shaped sheath section 4, the movable side energizing contact 32 is connected to the fixed side energizing contact 31.
And, at the same time, the movable contact 7 is connected to the fixed contact 6,
At the same time, the slide contact 37 fixed to the intermediate structure 38 slides on the puffer cylinder 8, but before the fixed contact 6 and the movable contact 7 are separated, the fixed side energizing contact 31 and the movable side Since the current-carrying contact 32 opens, the fixed side current-carrying contact 3
The current flowing through the path of 1 - movable side energizing contact 32 - puffer cylinder 8 - slide contact 37 - intermediate structure 38 is cut off from the path of fixed side energizing contact 31 - movable side energizing contact 32. As a result, the air flows through the path of fixed contact 6 - movable contact 7 - puffer cylinder 8 - slide contact 37 - intermediate structure 38 . As the sliding progresses further, the fixed contact 6
The movable contact 7 is also separated, and an arc is generated between the fixed contact 6 and the movable contact 7.

On the other hand, on the vacuum shield section 5 side, the intermediate structure 3
8 slides on the movable side energizing contact 34, and at the same time, the movable side energizing contact 34 slides on the fixed side energizing contact 33 fixed on the support fitting 40. However, since the movable contact 17 is kept in contact with the fixed contact 16 by the wiping device 35, the movable side energizing contact 34 is removed before the movable contact 17 and the fixed contact 16 are separated. Then, the fixed side energizing contact 33 opens. As a result, the intermediate structure 38 - the slide contact 39 - the movable side energizing contact 34 - the fixed side energizing contact 33
- The current flowing through the path of the support fitting 40 is cut off from the path of the movable side energizing contact 34 - the fixed side energizing contact 33, and the current flows through the intermediate structure 38 - slide contact 39 - wipe device 35 - movable contact. The liquid flows through the path of the contact 17 - fixed contact 16 - support fitting 40 . As the sliding progresses further, the movable contact 17 and the fixed contact 16, which were kept connected by the wipe device 35, are separated, and the movable contact 17 and the fixed contact 1 are separated.
An arc occurs between 6 and 6.

In the state where each shear cutting part extinguishes the arc and completes the shear cutting, each movable contactor 7, 17 is separated from each fixed contactor 6, 16, and insulation is maintained.

In this way, in the shear breaker shown in Figure 2, the current flows through the current-carrying contact, which has a larger contact area than the contacts on the puffer-type sheath section and the vacuum sheath section. Can be made larger.
However, in the above-mentioned sheath cutting device, it is necessary to provide a wipe device on the vacuum shield cutting part side to adjust the stroke between the movable contact of the vacuum shield cutting part and the movable side energizing contact. Therefore, the number of parts is large, the structure is complex, and the structure is large. Further, the fact that there are two contact portions of the movable current-carrying contact that can become a heat source due to poor contact also causes a decrease in reliability.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art and to provide a shear breaker device that has a simple structure, high reliability, and is capable of increasing the current flow.

In order to achieve this object, the present invention provides a puffer-shaped sleeve section that includes at least one pair of fixed contacts and a movable contact that can be brought into and out of contact with each other, and at least one pair of fixed contacts and a movable contact that can be brought into and out of contact with each other. A vacuum shield and a section are arranged such that the fixed contact sides thereof face each other, and the fixed contacts of the puffer type shield and the vacuum shield section are directly connected to each other. In the structure in which both the vacuum shield and the disconnection parts are connected in series, the vacuum shield is connected to the fixed terminal on the movable contact side that is electrically connected to the movable contact of the vacuum shield disconnection part through the outer periphery of the vacuum shield disconnection part. A fixed-side energizing contact extending to the puffer-shaped sheath section is attached, and a movable-side energizing contact that comes into contact with the fixed-side energizing contact in the puffer cylinder of the puffer-shaped sheath section in the inserted state. It is characterized by the provision of a contactor for use.

Hereinafter, one embodiment of the present invention will be described in detail with reference to FIG.

This shear cutting device has a puffer type sheath section 4 and a vacuum sheath section 5 housed in one container 41, and the container 41 is filled with SF ₆ gas.
The puffer type sheath section 4 and the vacuum sheath section 5 are similar to those in FIG.
are connected in series by directly connecting them.

The movable contact side terminal 21 of the vacuum shield section 5 includes:
A fixed-side energizing contact 42 is attached to extend through the outer periphery of the vacuum shield section 5 to the puffer-type shield section 4. This fixed side energizing contact 42 has a cylindrical shape, and has a shape in which the vacuum shield section 5 is housed. On the other hand, the puffer cylinder 8 of the puffer-shaped sheath section 4 is provided with a movable energizing contact 43 that comes into contact with the fixed energizing contact 42 in the closed state. In this embodiment, the outer circumferential surface of the distal end of the puffer cylinder 8 serves as the movable-side energizing contact 43, but the movable-side energizing contact 43 may be provided protruding from the distal end of the puffer cylinder 8. Further, a bellows 22 provided between the movable part and the fixed part of the vacuum shield section 5 is provided so as to protrude to the outside of the vacuum container 18.
The rest of the configuration is the same as that in FIG. 1 except that a non-linear resistor and a capacitor are not provided, so corresponding parts are given the same reference numerals and a description thereof will be omitted.

With the above configuration, in the closed state, the center conductor 13 of one bushing - the piston support fitting 11 - the piston 10 - the puffer cylinder 8 - the movable side energizing contact 43 - the fixed side energizing contact 42 - the vacuum shield Movable contact side terminal 21 of cut section 5
- A current will flow through the center conductor 24 of the other bushing. Since the energizing contacts 42 and 43 can have a large contact area, even when the energizing current is sufficiently large in a steady state, it is possible to maintain a stable energizing state without generating heat or welding at the contact portion. Further, the fixed side energizing contact 42 is connected to the movable contact side terminal 21 of the vacuum shield section 5.
Since it extends from the vacuum shield through the outer periphery of the vacuum shield section 5 to the movable side of the puffer-type shield section 4, the contact parts of the contacts 16 and 17 of the vacuum shield section 5 are short-circuited in the closed state. The current flowing in the steady state is controlled by the current carrying contact 4 with a large current carrying capacity.
Therefore, there is no concern about heat generation or welding even if the current carrying capacity of the contacts 16 and 17 of the vacuum shield and disconnection section 5 is insufficient, and there is no need to worry about heat generation or welding. Since only a small force is required and the contact area is also small, the vacuum shield and the cutting section can be made small and require a small operating force. This is also convenient for housing the vacuum shield section 5 within the cylindrical fixed-side energizing contact 42. moreover,
The shunt current also flows through the contact parts of the contacts 6 and 7 of the puffer-shaped shield section 4 and the contacts 16 and 17 of the vacuum shield section 5, but even if the contact resistance is large in these parts, heat is generated. Therefore, materials with low wear and tear can be freely selected for the contacts that generate arcs, which is advantageous in terms of device design.

The shearing operation is performed as follows. When an overcurrent flowing through an overcurrent detection device (not shown) is detected, and a tripping signal is transmitted to the cutting device and the cutting operation begins, a drive (not shown) using the repulsive force of a spring, high pressure air, hydraulic pressure, etc. The lever 15 is driven by the force generation mechanism, and the insulated operation rod 14 connected to the calendar bar 15, the puffer cylinder 8, the movable contact 7, the movable side energizing contact 43, and the nozzle 9 made of insulator are moved to the right in the figure. driven in the direction.

At this time, the movable side energizing contact 43 is electrically and mechanically connected to the fixed side energizing contact 42 which is fixed to the movable contact side terminal 21 of the vacuum shield section 5, and the movable contact 7 is fixed. It is driven while sliding with the contactor 6.

The drive is advanced, and the movable contact 7 and the fixed contact 6
If the fixed-side current-carrying contact 42 and the movable-side current-carrying contact 43 open before they open, the center conductor 13 of one brushing - the piston support fitting 11 - the piston 10 - the puffer cylinder 8 - the movable side current-carrying contact 43 - fixed side energizing contact 42 -
The current flowing through the movable contact terminal 21 of the vacuum shield disconnection section 5 and the center conductor 24 of the other bushing is cut off from the path of the movable side energizing contact 43 and the fixed side energizing contact 42. Contacts 6 and 7 of puffer type sheath section 4 and contact 1 of vacuum sheath section
6 and 17 maintain contact, current flows through the center conductor 13 of one bushing - the piston support fitting 11 - the piston 10 - the puffer cylinder 8 -
Movable contact 7 - Fixed contact 6 - Fixed contact 16 of vacuum shield section 5 - Movable contact 1 of vacuum shield section 5
7 - The movable contact side terminal 21 of the vacuum shield section 5 flows through the center conductor 24 of the other bushing, and an arc is generated between the fixed side energizing contact 42 and the movable side energizing contact 43. There's nothing to do.

Next, as the drive progresses further, the fixed contact 6 and the movable contact 7 of the puffer-shaped sheathed portion 4 are separated, and an arc is ignited between the contacts 6 and 7. Furthermore, the separation distance between these contacts 6 and 7 becomes sufficiently large, and the pressure inside the part furring 8 becomes sufficiently high, so that the dielectric strength between both contacts 6 and 7 after the current is cut off is reduced by the breakage device. When the voltage applied to all points can be withstood, the lever 26 is driven, and the insulating rod 25 and the movable contact 17 of the vacuum shield breaking section 5 are driven to the left in the figure to break the vacuum shield. contactor 16 of section 5,
17 is released. By doing this, di/dt
After the interruption of a large current of Due to the thermal history between the electrodes and the broken electrodes, the recovery of dielectric strength is not sufficient, and the impedance remains low. On the other hand, the vacuum insulation recovery speed is faster than that of the puffer type insulation, so
The impedance between the poles increases. Therefore, immediately after the current sheath is interrupted, especially for a period of about 0 to 10 μs, a transient recovery voltage is applied to the vacuum sheath due to the impedance relationship. In addition, if the partial pressure on the puffer die or cut side is large and thermal destruction is about to occur, the impedance of the puffer die or cut side will drop rapidly, so the voltage will be shared automatically by the vacuum seal or cut side. becomes larger. After passing through the performance-determining region due to thermal breakdown, the dielectric strength of the puffer molded sheath section recovers significantly, so even if dielectric breakdown occurs on the vacuum shredded section side, the puffer molded sheath section remains insulated. It will not lead to destruction.

In addition, in the above-mentioned shear cutting device, the puffer mold sheath section and the vacuum sheath section are housed in the same container, so the gas pressure around the vacuum sheath section is lower than that of the puffer mold cutter. , and a larger gas pressure will be applied to the bellows than in the case shown in Figure 1, but since the bellows is installed so as to protrude to the outside of the vacuum vessel as described above, the steady state ( In the loaded state), it is in a compressed state, that is, in a state where its strength against gas pressure is high, so it can withstand high gas pressure.

Moreover, compared to the one shown in FIG. 2, since the current-carrying contact has only one contact portion, the risk of malfunctions due to poor contact is reduced to half that of the conventional method, and high reliability can be obtained. In addition, the current-carrying contact is designed to short-circuit both the puffer-shaped sheath section and the vacuum shield section at once, and is opened and closed by moving the puffer cylinder. This eliminates the need for a wiping device that was required on the side of the blade, which reduces the number of parts, simplifies the structure, and makes it more compact, which not only reduces costs, but also improves reliability from this perspective. can be done.

FIG. 4 shows another embodiment of the invention. In this figure, the same or corresponding parts as in FIG. 3 are given the same reference numerals. This embodiment differs from the one shown in FIG. 3 in that a capacitor 28 is connected in parallel to the puffer type sheath section 4, and a nonlinear resistor 27 is connected in parallel to the vacuum sheath section 5. capacitor 2
8 is a part of the fixed-side energizing contact 42 cut out, and the fixed contact side terminal 20 of the vacuum shield section 5 (also the stationary contact side terminal of the puffer type shield section 4) and the puffer type The non-linear resistor 27 is inserted between the piston support fitting 11 of the vacuum shield section 4 and the fixed contact side terminal 20 of the vacuum shield section 5 and the fixed side energizing contact 42. ing. The non-linear resistor 27 is particularly preferably one whose main component is zinc oxide. The interelectrode voltage of the vacuum shield is low;
Since it is from several kV to several tens of kV, the nonlinear resistance 2
7 may be small in size, and can be placed inside the fixed-side energizing contact 42.

According to this embodiment, most of the initial part of the transient recovery voltage after the current shield is applied to the vacuum shield by the capacitor 28 inserted in parallel with the puffer type shield. That will happen. On the other hand, when the recovery voltage becomes high and exceeds the voltage limit of the non-linear resistor 27, all voltages higher than that will be applied to the puff-shaped shield. Therefore, there is an advantage that the current carrying capacity can be increased by fully utilizing the characteristics of the vacuum shield section and the puffer type shield section.

As explained above, according to the present invention, in a shear cutting device in which a puffer-type sheath section and a vacuum sheath section are connected in series, an energizing contact that short-circuits both sheath sections at once. The current carrying capacity can be increased, and since the current carrying contact only has one contact point and no wiping device is required, the structure is simple and compact, and reliability is improved. There are advantages.

[Brief explanation of the drawing]

1 and 2 are longitudinal cross-sectional views showing a conventional shearing device, respectively, and FIGS. 3 and 4 are longitudinal cross-sectional views showing a shearing device according to an embodiment of the present invention, respectively. 4...Passfire type sheath section, 5...Vacuum sheath section, 6...Fixed contact, 7...Movable contact, 8...
...Paper cylinder, 16...Fixed contact, 17
... Movable contact, 18 ... Vacuum container, 21 ... Movable contact side terminal, 22 ... Bellows, 27 ... Nonlinear resistance, 28 ... Capacitor, 41 ... Container,
42... Fixed side energizing contact, 43... Movable side energizing contact.

Claims (1)

[Scope of Claims] 1. A puffer-shaped shear section equipped with at least one pair of fixed contacts and a movable contact that can be moved toward and away from each other, and a vacuum equipped with at least one pair of fixed and movable contacts that can be moved toward and away from each other. The shields are arranged such that their fixed contact sides face each other, and the fixed contacts of the puffer type shield and the vacuum shield are directly connected to each other. In the case where the vacuum shield section is connected in series with the fixed terminal on the movable contact side that is electrically connected to the movable contact side of the vacuum shield section, the puffer type is connected through the outer periphery of the vacuum shield section. a movable side current-carrying contact that is attached to a fixed-side current-carrying contact that extends to the fixed-side current-carrying contact, and that contacts the fixed-side current-carrying contact when the puffer-type plastic shield is in a state of being inserted into the puffer cylinder of the puffer-type plastic cylinder; A shear cutting device characterized by being provided with. 2. The shear cutting device according to claim 1, wherein the stationary side energizing contact is a cylindrical body that accommodates the vacuum shear cutting portion inside. 3 In claim 1 or 2,
The vacuum sheath section is housed in the same gas pressure vessel as the puffer-type sheath section, and the bellows provided between the movable section and the fixed section of the vacuum sheath section protrudes to the outside of the vacuum vessel. A shear cutting device characterized in that it is attached to. 4. According to any one of claims 1 to 3, a non-linear resistance is connected between the fixed contact side terminal of the vacuum shield section and the fixed side energizing contact. Shiya cutting device. 5. In any one of claims 1 to 3, a non-linear resistance is connected between the fixed contact side terminal of the vacuum shield section and the fixed side energizing contact, and the puffer type A shear breaker device characterized by a capacitor connected in parallel to the shear breaker.