CN110634713A

CN110634713A - Instantaneous switch for asymmetric current source

Info

Publication number: CN110634713A
Application number: CN201910612092.1A
Authority: CN
Inventors: 薛占钰; 邢进春; 张同刚
Original assignee: Baoding Yuxin Electrical Technology Co ltd
Current assignee: Baoding Yuxin Electrical Technology Co ltd
Priority date: 2019-07-08
Filing date: 2019-07-08
Publication date: 2019-12-31

Abstract

The invention discloses a momentary switch for an asymmetric current source, which comprises a first conductor block connected with a high-voltage incoming line end and a second conductor block connected with an outgoing line end, wherein an insulating region is formed between the first conductor block and the second conductor block, and the momentary switch also comprises a moving conductor block which enables the first conductor block and the second conductor block to be conducted within a preset time and then restores the insulating state when penetrating through the insulating region. The device can realize that the non-fault phase is switched on in a short enough time, thereby indicating the fault and not causing negative influence to the line.

Description

Instantaneous switch for asymmetric current source

Technical Field

The invention relates to an asymmetric current source for detecting single-phase grounding of a high-voltage line of a power system, in particular to an instantaneous switch of the asymmetric current source.

Background

At present, most power distribution networks in China adopt systems with central points not directly grounded, the power distribution systems have many and complex branches, and when single-phase ground faults occur in the systems, the fault points are very difficult to search due to small fault current and complex fault characteristics; a large amount of manpower, material resources and time are consumed for finding out a specific fault position, fault judgment generally depends on the experience of people or the investigation of fault line patrol personnel, the power failure operation time of equipment maintenance is long, and the power failure range is large. The utility model patent CN201859161U discloses an asymmetric current source, including secondary control part, electron PT, relay operation case and interchange high pressure vacuum contactor, the input of secondary control part is inserted to electron PT secondary side, and the output of secondary control part connects the relay operation case, and relay operation case control exchanges high pressure vacuum contactor's coil, and interchange high pressure vacuum contactor has threely, and the arbitrary double-phase of A, B, C three-phase is connected respectively to the side once, and the opposite side is established ties and is connect high voltage diode and current limiting resistor, and another termination ground of current limiting resistor. If a single-phase ground fault of the high-voltage line occurs, the ground phase-to-ground voltage is reduced, the non-fault phase-to-ground voltage is increased, the asymmetric current source supplies power to a fault indicator on the high-voltage line by enabling the non-fault phase to artificially form a closed loop with the ground, and the fault indicator emits light to indicate the fault line. Utility model CN202815149U has further optimized above-mentioned patent, only uses two interchange high pressure vacuum contactor just can realize above-mentioned function. Utility model CN20533704U further discloses a double-phase asymmetric current source of the adjustable type of resistance, can the ground connection characteristic current size of automatic adjustment to guarantee that earth fault can both make fault indicator luminous in order to instruct the trouble route at every turn. However, when the ac high-voltage vacuum contactor is used to control the on-off of the non-fault phase high-voltage line, the non-fault phase high-voltage line cannot be immediately switched off (for example, the time is shorter than 10 milliseconds) after the line is switched on, so that the time for artificially grounding the non-fault phase is too long (hundreds of milliseconds), and other accidents are easily caused, which becomes an important bottleneck limiting the popularization and application of the asymmetric current source.

Disclosure of Invention

It is an object of the present invention to provide a momentary switch for an asymmetric current source which enables the non-faulted phase to be switched on in a sufficiently short time to indicate a fault without adversely affecting the line.

In order to achieve the purpose, the invention adopts the following technical scheme:

a momentary switch for an asymmetric current source includes a first conductor block connected to a high voltage inlet terminal and a second conductor block connected to an outlet terminal, the first and second conductor blocks forming an insulating region therebetween, and a moving conductor block that, when passing through the insulating region, renders the first and second conductor blocks conductive for a predetermined time and restores the insulating state.

Preferably, the moving conductor block is located on an insulating slide and is slidable on the insulating slide so as to pass through the insulating zone.

Preferably, the mobile conductor block is positioned on the pivot arm and can pivot with the pivot arm to pass through the insulating region.

Preferably, the moving conductor block is free-falling under gravity to pass through the insulating region.

Preferably, the first and second conductor blocks are supported on the elastic member, and ends of the first conductor block protrude to form first contact terminals, ends of the second conductor block protrude to form second contact terminals, and ends of the moving conductor block protrude to form pressing ends, which press the first and second contact terminals when the moving conductor block passes through the insulating section and conducts the first and second conductor blocks.

Preferably, the elastic member is a pressure spring or an elastic rod, and the first contact end, the second contact end and the extrusion end are triangular or convex arcs.

Preferably, the moving conductor block is wrapped with an insulating sheath on both sides in the direction of motion.

In the invention, the moving conductor block passes through the insulating area between the first conductor block and the second conductor block on the high-voltage line to conduct between the first conductor block and the second conductor block, the conduction time can be controlled by controlling the moving speed of the moving conductor block, and the on-off of less than 10 milliseconds (generally controlled at 5 milliseconds) can be smoothly realized. When the momentary switch is used in an asymmetric current source, the first conductor block and the second conductor block are both in an insulated state before the moving conductor block penetrates into the insulating region and after the moving conductor block penetrates out of the insulating region, and the non-fault phase is not grounded. When a certain phase is grounded, the movable conductor block is triggered to penetrate into the insulating area, the first conductor block and the second conductor block are conducted in the process, the non-fault phase is artificially grounded to generate a characteristic current, the characteristic current is captured by the acquisition circuit and indicates a fault route, the non-fault phase is not grounded after the movable conductor block penetrates out of the insulating area in a preset time, the preset time is set to be about 5 milliseconds, the influence on a high-voltage line cannot be caused, and the defect that the non-fault phase grounding time of the traditional asymmetric current source is too long is overcome. The design can omit a current-limiting resistor and a diode, so that the whole device has a simple and reliable structure.

Drawings

FIG. 1 is a schematic structural view of example 1 of the present invention;

FIG. 2 is a schematic diagram of an asymmetric current source according to embodiment 1 of the present invention;

FIG. 3 is a schematic structural diagram of embodiment 2 of the present invention;

FIG. 4 is a schematic diagram of an asymmetric current source according to embodiment 2 of the present invention;

FIG. 5 is a schematic structural diagram of embodiment 3 of the present invention;

fig. 6 is a schematic structural diagram of a preferred embodiment of example 1 of the present invention.

Detailed Description

The invention is further illustrated by the following specific examples:

fig. 1 is a schematic structural diagram of a first embodiment of the present invention, the momentary switch is located in a box 1 of an asymmetric current source, a first conductor block 2 is connected to a line inlet end 201 of a high-voltage line (generally 10 KV), a wall bushing 3 is provided on the box 1 for insulating the high-voltage line from the box, a second conductor block 4 is connected to a line outlet end 401, and the first conductor block and the second conductor block form an insulating region 6. Two or three momentary switches according to the invention can be provided on a three-phase high-voltage line, the outlet end of the second conductor block being connected to ground. An insulating slide 51 is provided between the first conductor block and the second conductor block, a moving conductor block 5 is inserted into the insulating slide 51, the moving conductor block 5 is freely slidable on the insulating slide 51, the first conductor block 2 and the second conductor block 4 are conducted when the moving conductor block 5 is inserted into the insulating region 6, and the first conductor block 2 and the second conductor block 4 are restored to an insulating state after the moving conductor block 5 is separated from the insulating region 6. The moving conductor block 5 can be driven by a spring 52 at one end of the insulating rod 51, the spring 52 is charged and acts on the moving conductor block 5 after being released, so that the moving conductor block 5 moves rapidly on the insulating rod 51, passes through the insulating region 6 for a certain predetermined time, and conducts the first conductor and the second conductor during the time. The predetermined time is typically set to no greater than 10 milliseconds, such as 5 milliseconds, by controlling the lateral width of the first and second conductors along the insulator rod, and thus the width of the insulator region, the lateral width of the moving conductor block 5 along the insulator rod, the spring potential, the speed of movement through the insulator region 6, and the like. This causes the first and second conductor blocks to turn on for a predetermined time and then to return to an insulated state, thereby causing the asymmetric current source to generate a characteristic current. In order to enhance the repeatability, the other end of the insulating sliding rod can be provided with a spring 53, and when the first conductor block and the second conductor block need to be conducted next time, the moving conductor block penetrates through the insulating region 6 in a rebounding mode, so that the next instant conduction within the preset time is realized. The

springs

52 and 53 can be limited by the limiting card 501 to store potential energy and complete release at least once, and a return device can be added or the limiting card 501 can be arranged into a structure which can movably compress the springs and fix the springs.

In another preferred embodiment, a controllable magnetic field can be arranged along the direction of the insulating rod, so that the moving conductor block is bound with the static magnet, and the movement of the moving conductor block is controlled by the control of the magnetic field. In the method, the direction and the size of the magnetic field are well controlled, and the magnetic field is not easy to fatigue and is not easily influenced by the environment.

Fig. 3 and 4 are schematic structural views illustrating a second embodiment of the present invention, in which the moving conductor block 5 is disposed on a radial arm 54, the radial arm 54 is mounted on a rotating shaft 55, the rotating shaft is connected to a motor 56, and the motor drives the rotating shaft and the radial arm to rotate, so that the moving conductor block passes through the insulating region 6, thereby conducting the first conductor block 2 and the second conductor block 4. Repeated rotation of the radial arm 54 may effect the next turn on.

Fig. 5 is a schematic structural diagram of a third embodiment of the present invention, in which a first conductor block 2 and a second conductor block 4 are horizontally arranged, and a moving conductor block 5 is limited on the top of a box 1, the top of the box is provided with an inlet 101, the moving conductor block is released to freely fall when needed, or the moving conductor block can be given an initial speed by a spring, can enter a receiver below the box, and the top can be filled with the moving conductor block again and launched when needed for next conduction. Initial velocities can be provided to move the conductor blocks as follows: namely, an elastic rotating card 102 which can be rotated and reset is additionally arranged at the inlet 101 and is used for supporting the movable conductor block 5 above the box body, and a launching device 9 is arranged and consists of a bracket 902, an internal spring 901 and a limit pin 903 and is used for providing launching force for the movable conductor block.

The apparatus may be filled with SF6 gas to extinguish arcs.

Fig. 6 is another preferred embodiment of the present invention, which is an optimization of the embodiment shown in fig. 1. In the embodiment shown in fig. 1, since a certain gap is formed between the movable conductor block 5 and the first conductor block 2 and the second conductor block 4 under high pressure, the first conductor block and the second conductor block can be conducted, but in order to reduce the arc, the first conductor block can be mounted on the compression spring 801, the second conductor block can be mounted on the compression spring 802 (of course, the first conductor block and the second conductor block can be mounted on the transverse elastic rod respectively), and the end portions of the first conductor block and the second conductor block are protruded to form an arc shape or a triangular shape as the first contact end 803 and the second contact end 804 respectively, the two ends of the movable conductor block 5 are protruded to form a triangular shape or an arc shape as the pressing end 805, and when the movable conductor block passes between the first conductor block and the second conductor block, the two pressing ends respectively contact and press the first contact end and the second contact end, so that the arc-drawing can be reduced, the life is increased.

In order to reduce the arc light generated during the movement, insulating jackets can be added on both sides of the moving conductor block in the direction of movement.

The above embodiments are merely illustrative of the inventive concept and implementation, and are not limiting, and technical solutions that are not substantially changed under the inventive concept are still within the scope of protection.

Claims

1. A momentary switch for an asymmetric current source comprising a first conductor block connected to a high voltage inlet terminal and a second conductor block connected to an outlet terminal, the first and second conductor blocks forming an insulated region therebetween, further comprising a moving conductor block which, when it passes through the insulated region, renders the first and second conductor blocks conductive for a predetermined time and then re-establishes the insulated state.

2. The momentary switch for asymmetric current sources according to claim 1, wherein the moving conductor block is located on an insulating slide and is slidable thereon so as to pass through the insulating region.

3. A momentary switch for an asymmetric current source as claimed in claim 1, wherein the shifted conductor block is located on the arm and can be rotated with the arm so as to pass through the insulating region.

4. The momentary switch for asymmetric current sources as claimed in claim 1, wherein the moving conductor block is free-falling under gravity to pass through the insulating region.

5. A momentary switch for an asymmetric current source as claimed in any one of claims 1 to 4 wherein the first and second conductor blocks are supported on a resilient member and the end of the first conductor block projects to form a first contact end and the end of the second conductor block projects to form a second contact end, and the movable conductor block projects at both ends to form a pressing end which presses the first and second contact ends when the movable conductor block passes through the insulating region and makes the first and second conductor blocks conductive.

6. The momentary switch for an asymmetric current source according to claim 5, wherein the resilient member is a compression spring or a resilient lever, and the first contact end, the second contact end, and the pressing end are triangular or convexly curved.

7. Momentary switch for an asymmetric current source according to one of claims 1 to 4, wherein the moving conductor block is wrapped with an insulating jacket on both sides in the direction of movement.