JPH038231A - Circuit breaker - Google Patents

Abstract

PURPOSE:To effectively suppress surge of an electric breaker and make the breaker size small by fixing a cylindrical contact in an insulator spacer- embedded high voltage electrode and further fixing a cylindrical shield which works as a resistor in the side of the embedded high voltage electrode. CONSTITUTION:A current flow line among a fixed electrode 13, a movable electrode 14, a contactor 10, and a conductor is formed when the movable electrode 14 contacts with the inside of the contactor 10. The movable electrode 14 moves rightward according to an order of taking out and is parted from the contactor 10. When the tip of the movable electrode 14 is within a high voltage shield 11, discharge is not caused and after then an arc 17 is caused. The arc is generated between the movable electrode 14 and either the high voltage shield 11 or resistor coating 12. By this, a surge current is generated and transmitted but suppressed by the high voltage shield 11 and the resistor coating 12. Moreover, earthing accident is also avoided. The size of a circuit breaker is made small since a contact part 15 is composed by fixing an insulator spacer 9 in the contactor 10.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a new circuit device that takes into account the suppression of high frequency surges.

(Prior Art) It is generally known that high frequency surges occur when operating a disconnector. This high-frequency surge may cause ground faults, radio interference, low-voltage control circuit destruction accidents, and the like.

Therefore, a disconnector having measures against high frequency surges as shown in FIG. 3 and known from Japanese Patent Application Laid-Open No. 61-66510 has been proposed. That is, a grounded metal container 1 filled with insulating gas.
A pair of fixed electrodes 2a and 2b are housed in the housing facing each other. A movable electrode 3 is slidably disposed inside the fixed electrode 2b. The movable electrode 3 moves toward and away from the fixed electrode 2a to connect and disconnect one fixed electrode 2a and 2b. A ferromagnetic ring 4 is provided on the outer periphery of the fixed electrode 2a.
is disposed, and a shield 5a is further disposed on the outside thereof. A gap g is formed between the tip of the fixed electrode 2a and the tip of the shield 5a. Further, a shield 5b is provided outside the fixed electrode 2b.

The high frequency surge is absorbed by the inductance component of the ferromagnetic ring 4.

By the way, since the gap g is formed at the tip of the fixed electrode 2a, one turn current is prevented from flowing around the one ferromagnetic ring 4. Therefore, fixed electrode 2a
When the movable electrode 3 separates, an arc 6 is formed, and a disconnector surge occurs, a large voltage is applied to the gap g. There is a possibility that the streamer that has expanded before the formation of the arc 6 changes direction and heads toward the shield 5a, causing dielectric breakdown between the shield 5a and the movable electrode 3. In this state, the ferromagnetic ring 4 does not have a surge suppressing effect.

Furthermore, although the surge suppression effect is proportional to the amount of ferromagnetic ring 4, a shield 5a is provided on the outside of ferromagnetic ring 4, and equipment is required to install these. Space cannot be used effectively.

Furthermore, the voltage of the movable electrode 3 is applied in the radial direction of the grounded metal container 1, and two electric fields in the same direction are simultaneously applied to the gap g formed at the tip of the shield 5a.

For this reason, when dielectric breakdown occurs in the gap g and one turn of current flows, the surge suppressing effect is lost, and at the same time, the first developed streamer may reach the grounded metal container 1 and cause a ground fault.

For this reason, it is desirable to make the gap g sufficiently large.

(Problems to be Solved by the Invention) However, in order to increase the gap, it is necessary to increase the size of the grounded metal container, and it is necessary to reduce the size of the disconnector.

The present invention has been made in consideration of the above points, and an object of the present invention is to provide a small-sized disconnector that can effectively suppress disconnector surge.

[Structure of the invention]

(Means for Solving the Problem) In order to achieve the above object, in the present invention, a cylindrical contactor is fixed to the embedded high-voltage electrode of an insulating spacer, and a cylindrical contactor that acts as a resistance is attached to the side surface of the embedded high-voltage electrode. A high-voltage shield is fixedly attached to the high-voltage shield, and a contact portion is formed by a movable electrode that passes inside the high-voltage shield and makes contact with and separates from the contact, and the contact.

(Function) With this configuration, surges can be effectively suppressed by the high-voltage shield, and the disconnector can be downsized.

(Example) An example of the present invention will be described below with reference to FIG. S
An insulating spacer 9 is airtightly connected to a flange 7a of a grounded metal container 7, which is filled with an insulating gas such as F gas, through an O-ring 8. The insulating spacer 9 is composed of a cone-shaped insulator body 9a and a cylindrical embedded high-voltage electrode 9b embedded in the center of the insulator body 9a.

Furthermore, a contact 10 such as a multi-contact is disposed inside the embedded high-voltage electrode 9b.

Furthermore, a cylindrical high voltage shield 11 is fixed coaxially to one side of the embedded high voltage electric i9b. This high voltage shield 11 is made of a resistor or conductive material, and its outer surface is covered with a resistive coating 12.

Note that a current-carrying conductor (not shown) is connected to the other side of the embedded high-voltage electrode 9b.

A fixed electrode 13 connected to a current-carrying conductor (not shown) is insulated and supported within the grounded metal container 7. A movable electrode 14 is slidably disposed inside the fixed electrode 13. The movable electrode 14 is driven by an operating device (not shown), passes inside the high-voltage shield II, comes into contact with and separates from the inner surface of the contact 10, and opens and closes the energizing path. That is, the contact portion 15 is formed by the contact lO and the movable electrode 14. Note that 16 is a shield.

Next, the operating device (not shown) moves the movable m-pole 14 to the left in the figure and contacts the inner surface of the contact 10, so that the current path is changed between the fixed electrode 13 and the movable m-pole 14. It is formed between the electrode 14, the contactor 10, and a current-carrying conductor (not shown).

Then, the movable electrode 14 moves to the right and separates from the contactor 10 in response to a tripping command. The tip of the movable electrode 14 is a high voltage shield l
While it exists within l, there is no discharge, and then an arc 17 occurs. This arc 17 occurs between the movable electrode 14 and the high voltage shield 11 or resistive coating 12.

As a result, although a surge is generated and propagated, it is suppressed by the high voltage shield 11 and the resistance coating 12. Moreover, ground fault accidents are avoided.

In addition, the contact IO is fixed to the insulating spacer 9 and the contact part 15 is
, it is possible to downsize the disconnector.

Incidentally, the arc 17 is also generated when the movable electrode 14 is turned on.

Further, in this embodiment, the contact 10 is disposed inside the embedded high-voltage electrode 9b, but as shown in FIG.
It is also possible to obtain similar effects by arranging this on the side surface of the cylindrical embedded high-voltage electrode 9b.

Furthermore, the configurations of these embodiments can also be applied to three-phase equipment.

〔Effect of the invention〕

As explained above, in the present invention, a cylindrical contactor is fixed to the embedded high-voltage electrode of an insulating spacer, and a cylindrical high-voltage shield that acts as a resistance is further fixed to the side surface of the embedded high-voltage electrode. Since the contact portion is formed by the movable electrode that passes through the inside and contacts and separates from the contact, and the contact, it is possible to provide a small-sized disconnector that can effectively suppress new circuit surge.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a disconnector showing one embodiment of the present invention.
The figure is a sectional view of a disconnector according to another embodiment of the present invention, and FIG. 3 is a sectional view of a conventional disconnector.

Claims (1)

[Claims] an insulating spacer consisting of a grounded metal container filled with an insulating gas, an insulator body connected to the end face of the grounded metal container, and an embedded high-voltage electrode embedded in the center of the insulator body;
A cylindrical contactor fixed to the embedded high-voltage electrode, a cylindrical high-voltage shield located in the grounded metal container and fixed to the side surface of the embedded high-voltage electrode and acts as a resistor, and insulated and housed in the grounded metal container. A disconnector comprising a movable electrode that passes through the inside of the high-voltage shield and connects and disconnects the contactor to open and close an energizing path.