CN201887468U

CN201887468U - Device for limiting all overvoltage

Info

Publication number: CN201887468U
Application number: CN2010206838325U
Authority: CN
Inventors: 肖飒
Original assignee: ANHUI SANHE ELECTRIC POWER TECHNOLOGY Co Ltd
Current assignee: ANHUI SANHE ELECTRIC POWER TECHNOLOGY Co Ltd
Priority date: 2010-12-28
Filing date: 2010-12-28
Publication date: 2011-06-29
Anticipated expiration: 2020-12-28

Abstract

The utility model relates to a device for limiting all overvoltage, which comprises an isolating handcart GL, wherein the wire inlet end of the isolating handcart GL is connected with a three-phase main bus-bar, and the wire outlet end of the isolating handcart GL is connected with a spike overvoltage absorption device and a high-voltage vacuum contactor ZJ which are both grounded; a high-voltage fuse FU2 and a voltage transformer PT are mounted on the isolating handcart GL; and the voltage transformer PT is connected with a microcomputer controller. In the device, the high-voltage vacuum contactor ZJ is used for eliminating the arc overvoltage; the spike overvoltage absorption device is used for eliminating the atmospheric overvoltage and the operational overvoltage; and the resonance overvoltage is eliminated by adopting different resonance-eliminating resistors to damage resonance condition. The device provided by the utility model not only has stabilization and quickness in action, but also has better limitation to the arc grounding overvoltage, the resonance overvoltage, the operational overvoltage and the atmospheric overvoltage.

Description

Full overvoltage Limiting device

Technical field

The utility model relates to a kind of full overvoltage Limiting device.

Background technology

At present, what the electric power system of China 3～35KV great majority adopted is the isolated neutral operational mode, and this operational mode allows the short time to operate with failure when single-phase earthing, thereby has improved the power supply reliability of system greatly.But along with the development of electrical network, overhead transmission line is progressively replaced by the cable line of solid insulation.Because the build-up effect that solid insulation punctures, its internal overvoltage, particularly arc grounding overvoltage that produces during electrical network generation single phase intermittent arc grounding and the ferro-resonance over-voltage that excites have thus become one of this class electric power netting safe running and have threatened greatly.Wherein serious with single-phase arc grounding overvoltage, it is saturated that the arc grounding overvoltage can make voltage transformer take place, and excites ferro resonance, causes voltage transformer seriously to transship, and causes fuse blows or instrument transformer to burn.Because arc grounding overvoltage longer duration, energy very easily surpass the ability to bear of lightning arrester, cause Explosion of on Arrester.

In order to address the above problem, domestic most employing arc suppression coil compensation or automatic tracking and compensating formula grounding through arc mode solve the arc grounding overvoltage problem at present, and its advantage has been to reduce the residual flow of fault point, helps extinguishing of ground arc; Avoid long-time arcing and caused the inter-phase arc short circuit; For metallic earthing, system can operate with failure two hours, and it is poor to have reduced step voltage.Its shortcoming is to be easy to generate series resonance over-voltage and illusory grounding phenomenon; Amplified the transmission overvoltage of transformer high-voltage side to low-pressure side; Little electric current line selection apparatus sensitivity is reduced even can't route selection; When going to offset capacitance current with inductive current, the high fdrequency component part during for arc grounding can't be offset, thereby can't limit the arc light grounding surge effectively.

The utility model content

The purpose of this utility model is to provide a kind of action fast stable, and the full overvoltage Limiting device that can carry out fine restriction to arc grounding overvoltage, resonance overvoltage, switching overvoltage, atmospheric over-voltage.

For achieving the above object, the utility model has adopted following technical scheme: a kind of full overvoltage Limiting device, comprise and isolate handcart GL, the inlet wire termination three-phase main bus bar of isolating handcart GL, the leading-out terminal of isolating handcart GL links to each other with spike overvoltage absorption plant, high-pressure vacuum contactor ZJ respectively, spike overvoltage absorption plant and high-pressure vacuum contactor ZJ ground connection, on the described isolation handcart GL high-tension fuse FU2 and voltage transformer pt are installed, described voltage transformer pt links to each other with microcomputerized controller.

As shown from the above technical solution, the utility model is eliminated arc overvoltage by high-pressure vacuum contactor ZJ; Eliminate atmospheric over-voltage and switching overvoltage by spike overvoltage absorption plant; Thereby destroy condition of resonance elimination resonance overvoltage by dropping into different harmonic elimination resistance.The utility model not only moves fast stable, and can well limit arc grounding overvoltage, resonance overvoltage, switching overvoltage, atmospheric over-voltage.

Description of drawings

Fig. 1 is primary circuit figure of the present utility model.

Embodiment

A kind of full overvoltage Limiting device, comprise and isolate handcart GL, the inlet wire termination three-phase main bus bar of isolating handcart GL, the leading-out terminal of isolating handcart GL links to each other with spike overvoltage absorption plant 1, high-pressure vacuum contactor ZJ respectively, spike overvoltage absorption plant 1 and high-pressure vacuum contactor ZJ ground connection, on the described isolation handcart GL high-tension fuse FU2 and voltage transformer pt are installed, described voltage transformer pt links to each other with microcomputerized controller, as shown in Figure 1.The utility model is converted into metallic earthing with arc grounding in 30mS when system's generation arc grounding, with arc grounding overvoltage Limiting on-Line Voltage level.Spike overvoltage absorption plant 1 adopts the parallel connection of a plurality of high energy ZnO valve block in this device, can effectively limit various overvoltage spikes, relax overvoltage wave head steepness, and it is big to absorb the overvoltage energy, and the 2ms square wave current can reach 3200A.

As shown in Figure 1, the leading-out terminal of described isolation handcart GL links to each other with high-pressure vacuum contactor ZJ by high-voltage and current-limitation fuse FU1, and high-pressure vacuum contactor ZJ is by current transformer CT ground connection.Described high-tension fuse FU2 links to each other with voltage transformer pt, and the neutral point of voltage transformer pt is by intelligent earthed switch K ground connection, and the secondary outlet of current transformer CT is connected with ammeter.When ferro resonance, single phase ground fault eliminate that the back three-phase voltage restores balance or during intermittent arc grounding, intelligence earthed switch K instantaneous operation, significantly reduce the impact of capacitance current, avoid voltage transformer pt to burn out problem with fuse failure voltage transformer pt.

When this device normally moves, microcomputerized controller is by gathering the secondary singal of voltage transformer pt, the ruuning situation of real-time monitoring system voltage, big fluctuation appears when detecting the voltage transformer pt secondary voltage, come the character and the kind of comprehensive failure judgement to make corresponding processing according to the amplitude of voltage transformer pt three-phase voltage and the amplitude and the angle of residual voltage: to be judged as arc grounding, microcomputerized controller sends instruction, high-pressure vacuum contactor ZJ closes a floodgate, the voltage of fault phase is reduced to zero potential, simultaneously with the level of the voltage limit on-Line Voltage of non-fault phase, system can be operated with failure 2 hours, for the time has been striven in the back brake operation of equipment; When being judged as system resonance, microcomputerized controller drops into different harmonic elimination resistance elimination resonance according to the character of resonance; When being judged as metallic earthing, the route selection module of microcomputerized controller shows the route selection result on the LCDs of microcomputerized controller, by the RS485 interface judged result of microcomputerized controller is passed to the backstage simultaneously and reports to the police.This device can be remembered data such as 50 fault types, time of origin, for accident analysis and processing provide information; Be furnished with RS485 microcomputer communication interface, can realize remote data communication with user's Computerized monitor system.

Claims

1. full overvoltage Limiting device, it is characterized in that: comprise and isolate handcart GL, the inlet wire termination three-phase main bus bar of isolating handcart GL, the leading-out terminal of isolating handcart GL links to each other with spike overvoltage absorption plant (1), high-pressure vacuum contactor ZJ respectively, spike overvoltage absorption plant (1) and high-pressure vacuum contactor ZJ ground connection, on the described isolation handcart GL high-tension fuse FU2 and voltage transformer pt are installed, described voltage transformer pt links to each other with microcomputerized controller.

2. full overvoltage Limiting device according to claim 1 is characterized in that: the leading-out terminal of described isolation handcart GL links to each other with high-pressure vacuum contactor ZJ by high-voltage and current-limitation fuse FU1, and high-pressure vacuum contactor ZJ is by current transformer CT ground connection.

3. full overvoltage Limiting device according to claim 1 is characterized in that: described spike overvoltage absorption plant (1) adopts the parallel connection of a plurality of high energy ZnO valve block.

4. full overvoltage Limiting device according to claim 1 is characterized in that: described high-tension fuse FU2 links to each other with voltage transformer pt, and the neutral point of voltage transformer pt is by intelligent earthed switch K ground connection.