JPH0715078Y2 - Disconnector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a disconnecting switch with resistance used in a gas insulated switchgear.

(Prior Art) Disconnectors are used for disconnecting equipment from the power supply when inspecting equipment, changing circuit connections, and opening and closing electrical circuits. There are various types for voltage. In such a disconnector, when the electric circuit is opened or closed, re-ignition generally occurs and a high surge voltage is generated. In order to suppress this surge voltage and keep the insulation of the electric circuit safe, a method has been proposed in which a resistor is attached to the re-ignition path of the disconnector.

FIG. 2 shows the configuration of a conventionally proposed disconnecting switch with resistance. That is, the insulating gas 2 such as SF ₆ gas is enclosed in the metal container 1, and the fixed contact portion C _f and the movable contact portion C _{m of} the disconnector are housed therein. Further, the fixed contact portion C _f
Is a fixed contact 10, a contact attachment conductor 6 to which the fixed contact 10 is attached, a shield 7 arranged so as to surround the fixed contact 10, a cylinder fixed to the conductor 6 and having the shield attached to the tip. It is composed of a conductor 4 which is supported by the metal container 1 by a rectangular resistor 8 and an insulating spacer 3a and communicates with the outside in an airtight state.

On the other hand, the movable contactor portion C _m is a movable contactor 9 which is disposed so as to be freely contactable with and separated from the fixed contactor 10 of the fixed contactor portion C _f , and a current collecting contactor which is in sliding contact with the movable contactor 9. 11, a shield 12 surrounding them, the current collector contact 11 and the conductor 5 to which the shield 12 is fixed and supported and fixed to the insulating spacer 3b. The movable contactor 9 is connected to an external driving device (not shown) via an insulating operation rod 13 and is configured to perform the opening and closing operations of the disconnector.

In the conventional disconnector thus configured, it is generally required to open / close the charging current of a short line. Here, the distributed capacitance and distributed inductance of the line, transformer, etc. are approximately represented by concentrated capacitance and concentrated inductance, respectively, and the charging current switching breaker circuit of the line is represented by an approximate equivalent circuit, as shown in FIG. become. In the figure, 14 is a power supply voltage, 15 is a short-circuit impedance, 16 is a power supply side capacitance, 17 is a power supply side inductance, 18 is a load side line capacitance, 19 is a load side line inductance, and 20 is a disconnector. . Also,
In the disconnector shown in FIG. 2, the insulation recovery characteristic between the tip of the movable contact 9 and the tip of the fixed contact side shield 7 is as shown in FIG.

When the circuit shown in FIG. 3 is cut off by the disconnecting switch having such characteristics, the voltage waveform as shown in FIG. 5 appears. That is, in FIG. 5, the solid line 21 shows the voltage waveform at the point “a” in FIG. 3, and the broken line 22 shows the voltage waveform on the power supply side. The difference between the solid line 21 and the broken line 22 is the voltage between contacts of the disconnector.

Explaining this relationship, for example, when the movable contactor 9 and the fixed contactor 10 are opened at point A, and then the tip of the movable contactor 9 comes out of the inside of the shield 7 of the fixed contactor portion. ,
The current is cut off at the point B, and the power supply voltage at this time remains in the capacitance 19 on the load side, and the voltage between contacts increases as the power supply voltage changes. Then, when the voltage between contacts exceeds the insulation recovery voltage, it is re-ignited at the point C. However, since the current is small, the current is immediately cut off and the voltage at this time remains in the load side capacitance 18. In this way, re-ignition is repeated, and as the insulation recovery voltage rises, the inter-electrode voltage during re-ignition also increases, but if the insulation recovery voltage exceeds the inter-electrode voltage, repeated re-ignition is stopped and the interruption is completed. To do. Re-ignition points C and D in Fig. 5
E, F, G, H correspond to the distance between the poles of C, D, E, F, G, H shown in FIG. The re-ignition phenomenon occurs between the shield 7 of the fixed contact and the tip of the movable contact 9, and a re-ignition arc 23 is formed as shown in FIG. When the contact opening operation is completed in this way, the movable contactor 9 is housed inside the shield 12 of the movable contactor portion. In addition, the shield 7 of the fixed contact portion and the shield 12 of the movable contact portion are
It has the function of making the electric field between the poles even and close to each other to increase the withstand voltage between the poles.

Now, in the disconnector as shown in FIG. 2, when the resistor 8 arranged in the fixed contact portion C _f is a metal conductor, it is between the movable contact 9 and the shield 7 of the fixed contact portion. When the re-ignition occurs, high frequency vibration occurs in the circuit of the capacitances 16 and 18 and the inductances 17 and 19 shown in FIG. 3, and the high frequency voltage 24 is generated as shown in FIG. This high-frequency voltage 24 increases as the voltage between contacts when the disconnector re-ignites is higher.
Further, the high frequency voltage 24 may threaten the insulation of the disconnector itself or other adjacent equipment. Therefore, in order to reduce the overvoltage at the time of re-ignition, as shown in FIG. 2, a resistor 8 is provided so that the electric current due to the re-ignition is applied to the conductor of the fixed contact portion C _f 4-contactor attachment conductor from 6 resistor 8 shield 7, flow in a path of the movable contactor 9 collector contact 11 conductor 5 of the movable contact portion C _m, by utilizing the loss of the circuit according resistors, the high-frequency voltage decreases I try to keep it down. As a disconnecting switch that suppresses overvoltage by passing a current during re-ignition through such a shield and resistor of the fixed contact,
There are those proposed in 53-38031 and Japanese Patent Publication No. 60-42570.

(Problems to be solved by the invention) However, in the conventional disconnector as described above,
There was a problem to be solved as described below.

That is, the shield 7 of the fixed contactor portion as shown in FIG.
Since the resistor 8 directly connected to the resistor has a large diameter and a long overall length, it is very difficult to manufacture the resistor. Further, since the resistor is large, the disconnector is also large.

The present invention has been proposed in order to solve the above drawbacks, and an object thereof is to provide a disconnector which realizes downsizing of a resistor and simplifies a manufacturing process.

[Structure of the Invention] (Means for Solving the Problem) A disconnector of the present invention stores a resistor disposed in a fixed contact portion inside a conductor to which the fixed contact is attached, and has one end thereof. Is connected to the shield of the fixed contact portion, and the other end is connected to the conductor.

(Operation) According to the disconnector of the present invention, the resistor, which has been conventionally directly connected to the shield of the fixed contact portion, can be housed inside the conductor to which the fixed contact is attached.
The resistor can be made smaller. Also, as the resistor,
Since the same lightning arrester can be used, its manufacturing process is also simplified.

(Embodiment) An embodiment of the present invention will be specifically described below with reference to FIG. Further, the same members as those of the conventional type shown in FIGS. 2 to 7 are designated by the same reference numerals, and the description thereof will be omitted.

In this embodiment, as shown in FIG. 1 (A), the resistor 30 provided in the fixed contactor C _f is formed by laminating disc-shaped resistors used in a lightning arrester or the like. This resistor 30 is mounted inside the contactor attachment conductor 6 substantially concentrically, and is connected to the contactor attachment conductor 6 and the shield 7 via the connection plate 31. An insulating cylinder or an insulating rod 32 is arranged around the resistor 30, and the resistor 30 is supported and fixed. In addition, the contact attachment conductor 6 and the resistor 30
The positional relationship of the connecting plate 31 for mounting is configured as shown in FIG. 1 (B). That is, the connecting plate 31 is composed of a disk-shaped central portion 31a in which the resistor 30 is arranged, two arm portions 31b extending outward from the central portion, and a connecting portion 31c, and the arm portion 31b is formed on the contact attachment conductor 6. Connection part through the hole 6a
It is connected to the shield 7 at 31c.

In the fixed contact portion C _f , the conductor 4, the contact attachment conductor 6, the resistor 30, the connecting plate 31, and the shield 7 are electrically connected in series.

In the disconnecting switch of this embodiment having such a structure, the overvoltage at the time of re-ignition is suppressed as described below.
That is, when re-ignition occurs between the movable contact 9 and the shield 7 of the fixed contact portion when the contact is opened, the current passes from the shield 7 through the connecting plate 31 to the fixed contact portion through the resistor 30. ,
It flows to the contactor attachment conductor 6 and the conductor 4. Therefore, the second
Similar to the conventional example shown in the figure, the loss of the resistor 30 effectively suppresses the overvoltage. Moreover, in this embodiment, since the resistor 30 is a disk-shaped member having a small diameter, the resistor 30 can be made smaller than a conventional cylindrical resistor having a large diameter. Further, as the resistor, a disk-shaped resistor that has been conventionally used in a lightning arrester or the like can be used, so that its manufacturing process can be used, and its manufacturing becomes easy. Further, since the resistor is not only formed in a disc shape but also disposed inside the contactor attachment conductor 6, the diameter of the fixed contactor portion can be reduced, and the disconnector as a whole can be downsized.

The present invention is not limited to the above-described embodiment, and the resistor provided in the fixed contact portion is formed in a cylindrical shape as long as it can be accommodated in the fixed contact attachment conductor. Anything is fine.

[Advantages of the Invention] As described above, according to the present invention, the resistor provided in the fixed contactor is housed inside the conductor to which the fixed contactor is attached, and one end thereof is fixed contactor. It is possible to provide a disconnector in which the resistor can be downsized and the manufacturing process can be simplified by a simple means of connecting to the shield and connecting the other end to the conductor.

[Brief description of drawings]

FIG. 1 shows an embodiment of the disconnector of the present invention.
(A) is a vertical sectional view, (B) is a horizontal sectional view, FIG. 2 is a sectional view showing an example of a conventional disconnector, and FIG. 3 is a diagram showing an approximate equivalent circuit of a line charging current switching breaker circuit. FIG. 4 is a diagram showing insulation recovery characteristics between the tip of the movable contact and the tip of the shield of the fixed contact, and FIG. 5 is a voltage waveform generated when the circuit is interrupted, FIG. FIG. 7 is a sectional view showing the conventional disconnecting switch shown in FIG. 2 when the contact is opened, and FIG. 7 is a diagram showing a high frequency voltage generated when re-ignition occurs. 1 ... Metal container, 2 ... Insulating gas, 3 ... Insulating spacer, 4 ... Conductor, 5 ... Conductor, 6 ... Contact mounting conductor, 7 ... Shield, 8 ... Resistor, 9 ... Movable contact, 10 …… Fixed contact, 11 …… Current collecting contact, 12 …… Shield, 13 …… Insulation control rod, 14 …… Power supply voltage, 15 …… Short circuit impedance, 16 …… Power supply side capacitance, 17 ……
Power supply side inductance, 18 …… Load side line capacitance, 19 …… Load side line inductance, 20 …… Disconnector,
21 …… Voltage waveform at "a" point in Fig. 3, 22 …… Power supply side voltage waveform, 23 …… Re-ignition arc, 24 …… High frequency voltage, 30 …… Resistor, 31 …… Connection plate, 32 …… Insulation rod.

Claims (1)

[Scope of utility model registration request] 1. A fixed contact part and a movable contact part are arranged facing each other in a container filled with an insulating gas, the fixed contact part is a fixed contact, a conductor to which the fixed contact is attached, and a fixed contact. A movable contact having a shield arranged so as to surround the child and a resistor arranged so as to be connected to the shield, and the movable contact portion being arranged so as to come in contact with and separate from the fixed contact. And a shield, etc., and the re-ignition discharge current generated in the opening and closing processes is configured to flow to the outside via the shield and the resistor of the fixed contact portion, The resistor provided in the contactor portion is housed inside a conductor to which the fixed contactor is attached, one end of which is connected to the shield of the fixed contactor portion, and the other end is connected to the conductor. Disconnector characterized by.