CN101587787A - Isolating switch - Google Patents

Abstract

The invention embodiment discloses an isolation switch, comprising a movable contact and a stationary contact. An arc-extinguishing device is installed on the movable contact and/or the stationary contact. The isolation switch introduces the arcing current generated between the contacts into a coil in the process of converting the current by turning on/off the bus. The coil forms a magnetic field. The electric arc can be extinguished stably, driven by a magnetic field force, thus reducing the arc erosion degree of the contact, effectively improving the ability of the isolation switch for converting the current by turning on/off the bus.

Description

an isolating switch

technical field

The invention relates to the field of high-voltage switchgear, more specifically, to an isolating switch.

Background technique

The isolating switch is the most widely used electrical appliance in the high-voltage switchgear. The main functions of the isolating switch include the following points:

1) After opening, establish a reliable insulation gap, and separate the equipment or lines that need to be repaired from the power supply with an obvious disconnection point to ensure the safety of maintenance personnel and equipment;

2) According to the operation needs, switch the line;

3) It can be used to divide and close small currents in the line, such as the charging current of bushings, busbars, connectors, and short cables, the capacitive current of switch equalizing capacitors, the circulating current when double busbars are switched, and the excitation current of voltage transformers wait;

4) According to the specific conditions of different structure types, it can be used to divide and combine the no-load excitation current of a transformer with a certain capacity.

The working principle and structure of the isolating switch are relatively simple, but due to the large amount of use and high reliability requirements, it has a great impact on the design, establishment and safe operation of substations and power plants. Ability is extremely important.

The existing isolating switch is composed of a moving contact and a static contact without an arc extinguishing device, and the material of the contact adopts an arc-resistant copper-tungsten alloy. When the disconnector switches on and off the bus to convert the current, it needs to switch on and off a certain loop load current. The isolating switch can reliably isolate the equipment working in a power failure from the live part, but because there is no arc extinguishing device, it can only break a specific circuit with a small current.

Since the opening and closing performance of the isolating switch is limited by the breaking capacity, if the opening and closing load is too heavy, the service life of the isolating switch will be greatly shortened. The isolating switch is feasible for breaking the small bus conversion current, but when breaking the large bus conversion current, the arc extinguishing ability will be too weak to reliably extinguish the arc, resulting in severe ablation of the contacts and the shielding cover, thus Reducing the insulation capacity between the fractures leads to breakdown, which eventually leads to breaking failure. Therefore, the prior art isolating switch has a very low switching current capability for breaking the busbar, and cannot reliably extinguish the arc, resulting in severe contact ablation.

Contents of the invention

In view of this, an embodiment of the present invention provides an isolating switch to solve the problems that the isolating switch has a weak switching current capability for switching off the busbar and severe contact ablation.

The embodiment of the present invention is realized like this:

An isolating switch, comprising a moving contact, a static contact and a coil, wherein an arc suppression device is installed on the moving contact and/or the static contact.

Preferably, in the above-mentioned isolating switch, the arc suppression device is arranged on the moving contact, and a support seat of the arc suppression device is installed on the moving contact.

Preferably, in the above isolating switch, the arc suppression device is arranged on the static contact, and a support seat of the arc suppression device is installed on the static contact.

Preferably, in the above-mentioned isolating switch, the arc suppression devices are respectively arranged on the moving contacts and the static contacts, and support seats of the arc suppression devices are respectively installed on the moving contacts and the static contacts.

Preferably, in the above isolating switch, the arc suppression device is a coil.

Preferably, in the above isolating switch, the coil is composed of a heat-resistant metal material and a heat-resistant shrink tube wrapped on the metal material.

Preferably, in the above isolating switch, the high heat-resistant metal material is copper wire.

Compared with the prior art, the technical solution provided by the embodiment of the present invention has the following advantages and characteristics: in the process of disconnecting the switching current of the bus bar, an arc is generated between the coil and the arcing contact, and the arc current enters the coil to form a magnetic field. The arc starts to rotate under the action of the magnetic field, and at the same time it is cooled, the arc is elongated, and finally the arc is extinguished safely when the current crosses zero. It can be seen that the design structure of the present invention improves the ability of the isolating switch to break the switching current of the bus bar, and reduces the extent of the contacts being ablated by the arc.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

FIG. 1 is a schematic diagram of an isolating switch provided by Embodiment 1 of the present invention;

FIG. 2 is a schematic diagram of a disconnector provided in Embodiment 2 of the present invention;

FIG. 3 is a schematic diagram of an isolating switch provided by Embodiment 3 of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

An isolating switch provided by an embodiment of the present invention includes a moving contact, a static contact, and a coil, wherein: a coil is provided on the contact, and a supporting seat for installing the coil is provided. There are many ways to install the above-mentioned coils and support bases, which will be described in detail through three specific examples below:

Embodiment one

Please refer to Fig. 1, the moving contacts in the isolating switch can be composed of moving main contacts 101 and moving arcing contacts 102, and the static contacts can be composed of static main contacts 103 and static arcing contacts 104; in the moving arcing contacts Coil 105 is installed on 102, and a support seat 106 for installing coil 105 is set. One end of the moving main contact 101 is connected to the mechanism through an insulating pull rod, and the other end of the moving main contact 101 and the moving arc contact 102 pass through the moving end contact seat. 107 connected, the static main contact 103 and the static arc contact 104 are connected by bolts; the moving arc contact 102 and the static arc contact 104 are made of materials resistant to arc ablation, generally copper-tungsten alloy; the coil 105 is made of Made of high heat materials, generally using copper wire and high heat resistant shrink tube.

The working process of the isolating switch is as follows:

When the isolating switch breaks the bus switching current, an arc 109 is generated between the moving and static contacts, and the arc current enters the coil to form a magnetic field 108. The arc 109 starts to rotate under the action of the magnetic field 108, and is cooled and elongated. Finally, it goes out safely when the current crosses zero.

Embodiment two

Please refer to Fig. 2, the coil 202 is installed on the static arc contact 201, and the supporting seat 203 for installing the coil is set, one end of the moving main contact 204 is connected with the mechanism through an insulating pull rod, and the other end of the moving main contact 204 is connected to the moving arc The contact 205 is connected through the moving end contact seat 206, and the static main contact 207 is connected with the static arc contact 201 through bolts; the moving arc contact 205 and the static arc contact 201 are made of materials resistant to arc ablation. Copper-tungsten alloy; the coil 202 is made of high heat-resistant material, generally using copper wire and high-heat-resistant shrink tube.

The working process of the isolating switch is as follows:

When the isolating switch breaks the busbar conversion current, an arc 209 is generated between the moving and static contacts, and the arc current enters the coil to form a magnetic field 208. The arc 209 starts to rotate under the action of the magnetic field 208, and is cooled and elongated. Finally, it goes out safely when the current crosses zero.

Embodiment Three

Please refer to Fig. 3 , a coil 303 and a support seat 304 are arranged on the moving arc contact 301 and the static arc contact 302 respectively, one end of the moving main contact 305 is connected with the mechanism through an insulating pull rod, and the other end of the moving main contact 305 is connected to the The moving arc contact 301 is connected through the moving end contact seat 306, and the static main contact 307 is connected with the static arc contact 302 through bolts; the moving arc contact 301 and the static arc contact 302 are made of materials resistant to arc ablation, Copper-tungsten alloy is generally used; the coil 303 is made of high heat-resistant material, generally copper wire and heat-resistant shrink tube.

The working process of the isolating switch is as follows:

When the isolating switch breaks the busbar conversion current, an arc 309 is generated between the moving and static contacts, and the arc current enters the coil to form a magnetic field 308. The arc 309 starts to rotate under the action of the magnetic field 308, and is cooled and elongated. Finally, it goes out safely when the current crosses zero.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (7)

1, a kind of isolating switch comprises moving contact and fixed contact, it is characterized in that, on described moving contact and/or the fixed contact arc-extinction device is installed.

2, isolating switch according to claim 1 is characterized in that, described arc-extinction device is arranged on the described moving contact, and the supporting seat of arc-extinction device is installed on described moving contact.

3, isolating switch according to claim 1 is characterized in that, described arc-extinction device is arranged on the described fixed contact, and the supporting seat of arc-extinction device is installed on described fixed contact.

4, isolating switch according to claim 1 is characterized in that, described arc-extinction device is separately positioned on described moving contact and the fixed contact, and the supporting seat of arc-extinction device is installed respectively on described moving contact and fixed contact.

According to claim 2,3 or 4 described isolating switches, it is characterized in that 5, described arc-extinction device is a coil.

6, isolating switch according to claim 5 is characterized in that, described coil is made up of high heat-proof metal material and the anti-high heat-shrinkable tube that is coated on the described metal material.

7, isolating switch according to claim 6 is characterized in that, described high heat-proof metal material is a copper cash.

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