CN106410748A - Neutral point protection device of transformer - Google Patents

Neutral point protection device of transformer Download PDF

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Publication number
CN106410748A
CN106410748A CN201610867813.XA CN201610867813A CN106410748A CN 106410748 A CN106410748 A CN 106410748A CN 201610867813 A CN201610867813 A CN 201610867813A CN 106410748 A CN106410748 A CN 106410748A
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CN
China
Prior art keywords
neutral point
transformer
protection device
gap
ball discharge
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201610867813.XA
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Chinese (zh)
Inventor
严玉婷
王亚舟
肖拴荣
胡燮
黄荣辉
唐峰
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Shenzhen Power Supply Bureau Co Ltd
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Shenzhen Power Supply Bureau Co Ltd
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Publication date
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Priority to CN201610867813.XA priority Critical patent/CN106410748A/en
Publication of CN106410748A publication Critical patent/CN106410748A/en
Pending legal-status Critical Current

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Classifications

    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02HEMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H7/00Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
    • H02H7/04Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for transformers
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02HEMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H9/00Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
    • H02H9/04Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage
    • H02H9/06Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage using spark-gap arresters

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Emergency Protection Circuit Devices (AREA)

Abstract

The invention discloses a neutral point protection device of a transformer. The neutral point protection device of the transformer comprises a metal oxide arrester and a ball electrode protection device, wherein the ball electrode protection device at least comprises a first discharge ball gap, a second discharge ball gap and a trigger electrode; the trigger electrode is used for discharging electricity to generate sparks under the action of high pulse voltage; and the electricity is discharged and the sparks are generated between the trigger electrode and the first discharge ball gap or the second discharge ball gap due to the high pulse voltage acting on the trigger electrode, so that the breakdown voltage between the first discharge ball gap and the second discharge ball gap is reduced and/or the ball gap between the first discharge ball gap and the second discharge ball gap is broken down. According to the neutral point protection device of the transformer, a neutral point protection gap of the transformer can reliably act during power frequency overvoltage, and does not act during lightning overvoltage and operation overvoltage, so that insulation of a neutral point of the transformer is protected; the condition that the arrester does not explode due to overlong current passing time is ensured; and the neutral point protection device of the transformer is reasonable in structure, safe, efficient and reliable.

Description

A kind of transformer neutral point protection device
Technical field
The present invention relates to power transformation engineering field, more particularly, to a kind of transformer neutral point protection device.
Background technology
In prior art, 110,220 KV transformer substation systems by the way of neutral point effective grounding, in order to limit single-phase connecing Ground short circuit electric current, prevents communication interference and relay protection configured in one piece etc. from requiring, some transformers neutral point is usually taken and does not connect Ground runs.
At present, the harm that lightning surge and the higher power-frequency overvoltage of amplitude insulate to transformer neutral point is larger, existing Some transformer neutral point protection devices generally adopt power frequency gap protection, lightning surge, switching overvoltage protection of arrester Scheme.But, from the point of view of current ruuning situation, portable protective gaps acting characteristic dispersibility is very big, the probability of malfunction Lifting, the reliability of impact operation of power networks, for example:Portable protective gaps malfunction under transient overvoltage causes zero-sequenceprotection action to jump master Transformator, portable protective gaps tripping under power-frequency overvoltage causes Explosion of on Arrester, and causes transformer neutral point to bear for a long time Power-frequency overvoltage, insulation safety is on the hazard.
Content of the invention
The technical problem to be solved is, provides a kind of transformer neutral point protection device, can make transformation Device protective gap of neutral point action message when there is power-frequency overvoltage, motionless when there is lightning surge and switching overvoltage Make, to protect transformer neutral point insulation it is ensured that spark gap will not be due to long and explode by current time;Structure is closed Reason, safe and efficient reliability.
In order to solve above-mentioned technical problem, The embodiment provides a kind of transformer neutral point protection device, bag Include:Metal oxide arrester;In parallel with metal oxide arrester in order to the ball electrode being triggered by spark discharge Protection device, ball electrode protecting device at least includes:First ball discharge gap, the second ball discharge gap and in order in pulse high-voltage In the presence of electric discharge produce pyrophoric trigger electrode, wherein:Act on the pulse high-voltage on trigger electrode make trigger electrode with Discharge between the first ball discharge gap or the second ball discharge gap and produce spark, make between the first ball discharge gap and the second ball discharge gap Sphere gap between breakdown voltage reduction and/or the first ball discharge gap and the second ball discharge gap punctures.
Wherein, transformer neutral point protection device also includes:In parallel with metal oxide arrester in order to transformator The power-frequency overvoltage of neutral point carries out the capacitive divider of partial pressure, and capacitive divider at least includes the first capacitive divider and with The second capacitive divider that one capacitive divider is connected, wherein:The power-frequency overvoltage of transformer neutral point is divided by capacitive divider Power-frequency voltage, power-frequency voltage and transformer neutral point have been got after pressure on the first capacitive divider or the second capacitive divider Power-frequency overvoltage is proportional.
Wherein, transformer neutral point protection device also includes:It is connected in parallel on the first capacitive divider or the second capacitive divider On isolating transformer;Be connected to the damping resistance on isolating transformer, and respectively with isolating transformer, damping resistance and gold Belong to the full-wave rectification bridge that Oxide Arrester is connected, wherein:Power-frequency voltage enters all-wave through damping resistance again through isolating transformer After rectifier bridge, rectification is DC voltage.
Wherein, transformer neutral point protection device also includes:Respectively with full-wave rectification bridge and metal oxide arrester phase Energy-storage capacitor even;The high pressure diac being connected with energy-storage capacitor;And the arteries and veins being connected with high pressure diac Rush transformator, wherein:DC voltage charges to energy-storage capacitor, triggers two poles when the charging voltage of energy-storage capacitor exceedes high pressure During the specified trigger voltage of pipe, high pressure diac triggers.
Wherein, after the triggering through high pressure diac for the energy-storage capacitor, the former limit of pulse transformer is discharged, and pulse becomes Depressor produces the pulse high-voltage acting on trigger electrode in its secondary.
Wherein, transformer neutral point protection device also includes:It is connected in parallel on the discharge resistance on energy-storage capacitor.
Wherein, metal oxide arrester is Zinc-Oxide Arrester.
Wherein, between trigger electrode and the first ball discharge gap or the second ball discharge gap, electric discharge produces spark can be the first ball discharge Electric field between gap and the second ball discharge gap provides a large amount of charged particles.
Implement the transformer neutral point protection device of the present invention, there is following beneficial effect:
Firstth, acting on the pulse high-voltage on trigger electrode makes between trigger electrode and the first ball discharge gap or the second ball discharge gap Discharge and produce spark, so that the breakdown voltage between the first ball discharge gap and the second ball discharge gap is reduced and/or the first ball discharge Sphere gap between gap and the second ball discharge gap punctures, and transformer neutral point protective gap can be made to occur power frequency excessively electric Action message during pressure, there is lightning surge and be failure to actuate during switching overvoltage, protecting transformer neutral point insulation it is ensured that Spark gap will not be due to long and explode by current time;Reduce the dispersibility of portable protective gaps action, preferably with Metal oxide arrester coordinates, and improves stability and the Reliability of Microprocessor of device.
Secondth, rational in infrastructure, safe and efficient reliability, can preferably ensure the stability of electrical network.
Brief description
In order to be illustrated more clearly that the embodiment of the present invention or technical scheme of the prior art, below will be to embodiment or existing Have technology description in required use accompanying drawing be briefly described it should be apparent that, drawings in the following description be only this Some embodiments of invention, for those of ordinary skill in the art, on the premise of not paying creative work, acceptable Other accompanying drawings are obtained according to these accompanying drawings.
Fig. 1 is the electrical block diagram of embodiment of the present invention transformer neutral point protection device.
Specific embodiment
Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out clear, complete Site preparation description is it is clear that described embodiment is only a part of embodiment of the present invention, rather than whole embodiments.It is based on Embodiment in the present invention, it is every other that those of ordinary skill in the art are obtained under the premise of not making creative work Embodiment, broadly falls into the scope of protection of the invention.
As shown in figure 1, the embodiment one for transformer neutral point protection device of the present invention.
Embodiments provide a kind of transformer neutral point protection device, including:Metal oxide arrester and ball Electrode protecting device.
Metal oxide arrester in the present embodiment is Zinc-Oxide Arrester MOA.
Ball electrode protecting device with metal oxide arrester MOA and couples, and its effect is to be touched by spark discharge Send out, play the effect of igniting, electronics causes puncturing of whole gas gap produced by the spark discharge of this local.
When being embodied as, ball electrode protecting device at least includes:First ball discharge gap G1, the second ball discharge gap G2 and use Pyrophoric trigger electrode J is produced with electric discharge in the presence of pulse high-voltage, wherein:The pulse acting on trigger electrode J is high Voltage makes trigger electrode J and the first ball discharge gap G1 or the second ball discharge gap G2(Put with second for trigger electrode J in the present embodiment Electric ball gap G2)Between discharge and produce spark, make the breakdown potential pressure drop between the first ball discharge gap G1 and the second ball discharge gap gap G2 Sphere gap between low and/or the first ball discharge gap G1 and the second ball discharge gap G2 punctures.
It is understood that according to actual use arrangement demand or trigger electrode J and the first ball discharge gap G1 Between discharge and produce spark, have no effect on enforcement.
Further, transformer neutral point protection device also includes:In parallel with metal oxide arrester MOA in order to right The power-frequency overvoltage of transformer neutral point carries out the capacitive divider of partial pressure.In the present embodiment, capacitive divider includes but does not limit The second capacitive divider C2 be connected in the first capacitive divider C1 and with the first capacitive divider C1, wherein:Transformator is neutral Point power-frequency overvoltage by after capacitive divider partial pressure in the first capacitive divider C1 or second capacitive divider C2 (the present embodiment In for power-frequency overvoltage by after capacitive divider partial pressure in the second capacitive divider C2) on got power-frequency voltage, this power frequency electric Pressure is proportional to the power-frequency overvoltage of transformer neutral point.
It is understood that being divided by capacitive divider using arrangement demand or power-frequency overvoltage according to actual Power-frequency voltage has been got on the first capacitive divider C1, this power-frequency voltage is become with the power-frequency overvoltage of transformer neutral point after pressure Ratio.Have no effect on enforcement.
Further, transformer neutral point protection device also includes:It is connected in parallel on the first capacitive divider C1 or the second electric capacity Isolating transformer T1 on potentiometer C2;Be connected to the damping resistance R1 on isolating transformer T1, and respectively with isolation transformation The full-wave rectification bridge D1 that device T1, damping resistance R1 are connected with metal oxide arrester MOA, wherein:Power-frequency voltage becomes through isolation It is DC voltage that depressor T1 enters rectification after full-wave rectification bridge D1 again through damping resistance R1.
Further, transformer neutral point protection device also includes:Keep away with full-wave rectification bridge D1 and metal-oxide respectively The energy-storage capacitor C that thunder device MOA is connected;The high pressure diac D2 being connected with energy-storage capacitor C;And trigger two with high pressure The pulse transformer T2 that pole pipe D2 is connected, wherein:DC voltage charges to energy-storage capacitor C, when the charging electricity of energy-storage capacitor C When pressure exceedes the specified trigger voltage of high pressure diac D2, high pressure diac D2 triggers.
Wherein, after the triggering through high pressure diac D2 for the energy-storage capacitor C, the former limit of pulse transformer T2 is discharged, arteries and veins Rush transformator T2 and produce the pulse high-voltage acting on trigger electrode J in its secondary.
Further, transformer neutral point protection device also includes:It is connected in parallel on the discharge resistance R2 on energy-storage capacitor C.
A kind of transformer neutral point protection device of the embodiment of the present invention in the specific implementation, is needing the first ball discharge gap During sphere gap action between G1 and the second ball discharge gap G2, introduce the spark discharge of a local, play ignition action, by local fire Electronics produced by flower electric discharge causes puncturing of whole gas gap.
Specifically, the power-frequency overvoltage of transformer neutral point is divided by the first capacitive divider C1 and the second capacitive divider C2 Power-frequency voltage has been got on the second capacitive divider C2, this power-frequency voltage becomes ratio with transformer neutral point power-frequency overvoltage after pressure Example, it is DC voltage that this power-frequency voltage enters full-wave rectification bridge D1 rectification through overdamp resistance R1 after isolating transformer T1, should DC voltage charges to energy-storage capacitor C, touches when the charging voltage of energy-storage capacitor C exceedes the specified of high pressure diac D2 During the pressure that generates electricity, wherein:The threshold value that the specified trigger voltage of high pressure diac D2 is previously set, high pressure diac D2 touches Send out, energy-storage capacitor C discharges through high pressure diac D2 pulse transformer T2 former limit, produce the high electricity of pulse in its secondary Pressure, this pulse high-voltage acts on trigger electrode J, at this moment discharges between trigger electrode J and the second ball discharge gap G2 and produce spark, Both ignition results had been produced, this electric discharge provides a large amount of band electrochondrias for the electric field between the first ball discharge gap G1 and the second ball discharge gap G2 Son, so that the breakdown voltage of sphere gap between the first ball discharge gap G1 and the second ball discharge gap G2 substantially reduces, finally makes first Sphere gap between ball discharge gap G1 and the second ball discharge gap G2 punctures.
Because the presence of damping resistance R1 is so that in lightning impulse voltage, the persistent period such as operating impulse voltage is shorter The lower energy-storage capacitor of transient overvoltage effect can not store enough energy, thus igniting trigger pulse electricity also would not be produced Pressure, so, under persistent period shorter transient overvoltage, the breakdown voltage of sphere gap will be very high, and igniting will not be occurred to touch Provide electricity, and malfunction will not occur under residual voltage of arrester.
In the other embodiment of transformer neutral point protection device of the present invention, the first ball discharge gap G1 and the second ball discharge The parameter of the ball electrode length between gap G2 and internal control circuit can be carried out adjusting, can be according to transformation in actual moving process The overvoltage level that device neutral point occurs, to determine size and the parameter of spark triggered gap each several part, to reach and avoid spark gap With the purpose of gap malfunction and tripping, protect transformer neutral point insulation, improve grid stability.
Implement the transformer neutral point protection device of the present invention, there is following beneficial effect:
Firstth, acting on the pulse high-voltage on trigger electrode makes between trigger electrode and the first ball discharge gap or the second ball discharge gap Discharge and produce spark, so that the breakdown voltage between the first ball discharge gap and the second ball discharge gap is reduced and/or the first ball discharge Sphere gap between gap and the second ball discharge gap punctures, and transformer neutral point protective gap can be made to occur power frequency excessively electric Action message during pressure, there is lightning surge and be failure to actuate during switching overvoltage, protecting transformer neutral point insulation it is ensured that Spark gap will not be due to long and explode by current time;Reduce the dispersibility of portable protective gaps action, preferably with Metal oxide arrester coordinates, and improves stability and the Reliability of Microprocessor of device.
Secondth, rational in infrastructure, safe and efficient reliability, can preferably ensure the stability of electrical network.

Claims (8)

1. a kind of transformer neutral point protection device is it is characterised in that include:
Metal oxide arrester;
In parallel with described metal oxide arrester in order to the ball electrode protecting device being triggered by spark discharge, described Ball electrode protecting device at least includes:First ball discharge gap, the second ball discharge gap and in order in the presence of pulse high-voltage Pyrophoric trigger electrode is produced in electric discharge, wherein:
Acting on the pulse high-voltage on described trigger electrode makes described trigger electrode and described first ball discharge gap or described the Discharge between two ball discharge gaps and produce spark, make the breakdown voltage between described first ball discharge gap and described second ball discharge gap Sphere gap between reduction and/or described first ball discharge gap and described second ball discharge gap punctures.
2. transformer neutral point protection device as claimed in claim 1 is it is characterised in that the protection of described transformer neutral point fills Put and also include:
The electric capacity in order to the power-frequency overvoltage of transformer neutral point is carried out with partial pressure in parallel with described metal oxide arrester Potentiometer, described capacitive divider at least includes the first capacitive divider and the second electricity being connected with described first capacitive divider Hold potentiometer, wherein:The power-frequency overvoltage of transformer neutral point is divided in described first electric capacity by after described capacitive divider partial pressure Power-frequency voltage has been got, described power-frequency voltage is excessively electric with the power frequency of transformer neutral point on depressor or described second capacitive divider It is pressed into ratio.
3. transformer neutral point protection device as claimed in claim 2 is it is characterised in that the protection of described transformer neutral point fills Put and also include:
It is connected in parallel on the isolating transformer on described first capacitive divider or described second capacitive divider;
It is connected to the damping resistance on described isolating transformer, and
The full-wave rectification bridge being connected with described isolating transformer, described damping resistance and described metal oxide arrester respectively, Wherein:
It is straight that described power-frequency voltage enters rectification after described full-wave rectification bridge again through described isolating transformer through described damping resistance Stream voltage.
4. transformer neutral point protection device as claimed in claim 3 is it is characterised in that the protection of described transformer neutral point fills Put and also include:
The energy-storage capacitor being connected with described full-wave rectification bridge and described metal oxide arrester respectively;
The high pressure diac being connected with described energy-storage capacitor;And
The pulse transformer being connected with described high pressure diac, wherein:Described DC voltage fills to described energy-storage capacitor Electricity, when the charging voltage of described energy-storage capacitor exceedes the specified trigger voltage of described high pressure diac, described high pressure Diac triggers.
5. transformer neutral point protection device as claimed in claim 4 is it is characterised in that described energy-storage capacitor is through described height Former limit electric discharge to described pulse transformer after the triggering of pressure diac, described pulse transformer acts in its secondary generation Described pulse high-voltage in described trigger electrode.
6. the transformer neutral point protection device as described in claim 4 or 5 is it is characterised in that described transformer neutral point is protected Protection unit also includes:It is connected in parallel on the discharge resistance on described energy-storage capacitor.
7. transformer neutral point protection device as claimed in claim 1 is it is characterised in that described metal oxide arrester is Zinc-Oxide Arrester.
8. transformer neutral point protection device as claimed in claim 1 is it is characterised in that described trigger electrode and described first Between ball discharge gap or described second ball discharge gap, electric discharge produces spark can be described first ball discharge gap and described second ball discharge Electric field between gap provides a large amount of charged particles.
CN201610867813.XA 2016-09-30 2016-09-30 Neutral point protection device of transformer Pending CN106410748A (en)

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Application Number Priority Date Filing Date Title
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112117745A (en) * 2019-06-20 2020-12-22 王嬿蕾 Dynamic insulation matching method and device for eliminating power frequency insulation strength loss
EP3747100B1 (en) * 2018-01-30 2022-03-16 Hitachi Energy Switzerland AG Surge arrestor dimensioning in a dc power transmission system

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1933268A (en) * 2006-09-06 2007-03-21 中国电力科学研究院 Controllable gap for protecting transformer neutral point
CN202997557U (en) * 2012-12-26 2013-06-12 宁夏电力公司吴忠供电局 Controllable trigger device for protecting 110kV transformer neutral point
CN103269058A (en) * 2013-06-13 2013-08-28 哈尔滨理工大学 Controllable gap, and device and method for protecting neutral point of 110KV transformer based on controllable gap
US20140334054A1 (en) * 2013-02-20 2014-11-13 Emprimus, Llc Overvoltage protection for power systems
CN206117123U (en) * 2016-09-30 2017-04-19 深圳供电局有限公司 Transformer neutral point protection device

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1933268A (en) * 2006-09-06 2007-03-21 中国电力科学研究院 Controllable gap for protecting transformer neutral point
CN202997557U (en) * 2012-12-26 2013-06-12 宁夏电力公司吴忠供电局 Controllable trigger device for protecting 110kV transformer neutral point
US20140334054A1 (en) * 2013-02-20 2014-11-13 Emprimus, Llc Overvoltage protection for power systems
CN103269058A (en) * 2013-06-13 2013-08-28 哈尔滨理工大学 Controllable gap, and device and method for protecting neutral point of 110KV transformer based on controllable gap
CN206117123U (en) * 2016-09-30 2017-04-19 深圳供电局有限公司 Transformer neutral point protection device

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3747100B1 (en) * 2018-01-30 2022-03-16 Hitachi Energy Switzerland AG Surge arrestor dimensioning in a dc power transmission system
CN112117745A (en) * 2019-06-20 2020-12-22 王嬿蕾 Dynamic insulation matching method and device for eliminating power frequency insulation strength loss

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