CN103269058A - Controllable gap, and device and method for protecting neutral point of 110KV transformer based on controllable gap - Google Patents
Controllable gap, and device and method for protecting neutral point of 110KV transformer based on controllable gap Download PDFInfo
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- CN103269058A CN103269058A CN2013102334197A CN201310233419A CN103269058A CN 103269058 A CN103269058 A CN 103269058A CN 2013102334197 A CN2013102334197 A CN 2013102334197A CN 201310233419 A CN201310233419 A CN 201310233419A CN 103269058 A CN103269058 A CN 103269058A
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Abstract
The invention relates to a controllable gap, and a device and method for protecting a neutral point of a 110KV transformer based on the controllable gap, and belongs to the technical field of the high voltage, solves such problems as anti-operation under the steady-state over-voltage and error operation under the transient-state over-voltage caused by the poor action stability in existing discharging gap, and solves the problem that a lightning arrester and the discharging gap in the existing protection method and protection device for the neutral point of the 110KV transformer are not clearly divided because the lightning arrester is just simply in parallel connection with the discharging gap. The method comprises the steps of: identifying the type of an over-voltage through a voltage-type identification and energy storage unit, transmitting a steady-state over-voltage to a triggering pulse forming unit through the voltage-type identification and energy storage unit when the over-voltage is a steady-state over-voltage, forming a triggering pulse signal through the triggering pulse forming unit, transmitting the triggering pulse signal to a controlled discharging gap, and enabling the controlled discharging gap to act; and enabling a zinc oxide lightning arrester (MOA) to act if the over-voltage is a transient over-voltage. The method and the device are mainly used for protecting a neutral point of the 110KV transformer.
Description
Technical field
The invention belongs to the high voltage technique field.
Background technology
Now Chang Yong 110KV electric power system Protection Mode of Transformer Neutral End mainly contains three kinds---lightning arrester, discharging gap, lightning arrester parallel spark gap.
The defective that " lightning arrester " guard method mainly exists is: can not protect long-term internal overvoltages such as power-frequency overvoltage, and self exist fault danger under higher power-frequency overvoltage, self need protection.Particularly when open-phase operation taking place or transfer the isolated neutral system of be with single-phase earthing to, because transformer neutral point voltage raises, may make the lightning arrester long period operate in voltage more than the rated voltage and destroyed, even set off an explosion.
The defective that " discharging gap " guard method mainly exists is: discharge dispersity is big, the protective feature instability, and power frequency continued flow is bigger, and the arc extinguishing ability is relatively poor, and a gap action meeting generation section ripple, and is unfavorable to transformer insulation itself.It is to be foundation with the gap action that the normal gap paradoxical discharge phenomenon that takes place in actual motion, gap breakdown cause the criterion of protective relaying maloperation rules regulation relaying protection action.And in power frequency, operation and three kinds of superpotential scopes of thunder and lightning, realize the definite difficulty of parameter that protection cooperates, practical application effect is not good.
The defective of " lightning arrester parallel spark gap " guard method is: residual voltage of arrester, excellent gap 50% thunder discharge lower voltage limit approach, and because the discharge dispersity of protecting the gap does not improve, the protection gap still has the possibility of action under residual voltage of arrester.In addition, neutral point insulation level, residual voltage of arrester and gap discharge voltage three's mix proportion is difficult.And the data that the laboratory provides measure under power frequency and lightning impulse situation respectively, differ greatly with actual operating mode.Reality multiple overvoltage often acts on neutral point simultaneously, causes gap misoperation and lightning arrester to damage blast easily.
Summary of the invention
The present invention is in order to solve the poor stability of existing discharging gap action; cause " tripping under the steady-state overvoltage " and " malfunction under the temporary overvoltage " problem; in the existing 110KV transformer neutral point guard method; just lightning arrester and discharging gap simply are together in parallel; and the two divides the work indefinite problem; existing 110KV transformer neutral point protective device; lightning arrester and discharging gap are divided the work indefinite problem, a kind of control gap is provided and has realized protective device and the method for 110KV transformer neutral point based on this control gap.
A kind of control gap, it comprises controlled flip-over type protection gap; Described controlled flip-over type protection gap forms the unit by overvoltage type identification and energy-storage units, trigger impulse and the controlled discharge gap is formed;
Described overvoltage type identification and energy-storage units are by capacitor C
1, capacitor C
2, isolating transformer T
1, the lightning protection resistance R
1, full-wave rectification bridge D
1, the current-limiting protection resistance R
2Form with pulsed capacitance C,
Described trigger impulse forms the unit by high pressure diac D
2With pulse transformer T
2Form,
Described controlled discharge gap is three electrode sphere gap switches, and described three electrode sphere gap switches comprise the first spheric electrode G
1, the second spheric electrode G
2With trigger electrode J; Capacitor C in described overvoltage type identification and the energy-storage units
1The a termination first spheric electrode G
1, described capacitor C
1The other end and capacitor C
2An end connect capacitor C
2Other end ground connection, described isolating transformer T
1Primary coil and capacitor C
2Be connected in parallel isolating transformer T
1One end of secondary coil and lightning protection resistance R
1An end connect isolating transformer T
1The other end of secondary coil and full-wave rectification bridge D
1AC signal input connect described full-wave rectification bridge D
1Another AC signal input and lightning protection resistance R
1The other end connect full-wave rectification bridge D
1Direct current cathode output end ground connection, full-wave rectification bridge D
1The direct-flow positive pole output simultaneously and the current-limiting protection resistance R
2The end of an end, pulsed capacitance C and trigger impulse form high pressure diac D in the unit
2Anode connects, described current-limiting protection resistance R
2The other end and the equal ground connection of the other end of pulsed capacitance C;
High pressure diac D
2Negative electrode and pulse transformer T
2An end of primary coil connect described pulse transformer T
2The other end ground connection of primary coil, described pulse transformer T
2An end of secondary coil be connected described pulse transformer T with trigger electrode J in the controlled discharge gap
2The other end ground connection of secondary coil;
The described second spheric electrode G
2Ground connection.
Based on a kind of protective device of control gap realization 110KV transformer neutral point, it comprises zinc oxide arrester MOA, control gap and 110KV transformer, the first spheric electrode G in the end of described zinc oxide arrester MOA and the controlled discharge gap
1All the neutral point with the 110KV transformer is connected, the capacitor C in the other end of described zinc oxide arrester MOA and overvoltage type identification and the energy-storage units
2The equal ground connection of the other end.
Realize that based on the protective device of 110KV transformer neutral point the guard method of 110KV transformer neutral point, its detailed process are,
At first, by voltage type identification and the identification of energy-storage units to the overvoltage type, obtain recognition result,
When recognition result is steady-state overvoltage, voltage type identification sends steady-state overvoltage to trigger impulse with energy-storage units and forms the unit, trigger impulse forms the unit and forms start pulse signal, and this start pulse signal is sent to the controlled discharge gap, the action of controlled discharge gap realizes the protection to the 110KV transformer neutral point;
When recognition result was temporary overvoltage, zinc oxide arrester MOA action realized the 110KV transformer neutral point is protected.
The beneficial effect that the present invention brings is; a kind of novel control gap is provided; the action of this kind control gap is strict; the stability of this kind control gap has improved 20%; and a kind of protective device and method of novel 110KV transformer neutral point are provided; make the division of labor of lightning arrester and discharging gap clear and definite; lightning arrester only shields to lightning overvoltage and Frequency Transient Overvoltage; and the power frequency steady-state overvoltage that only cause fault in the protection gap and asymmetric operating and the resonance overvoltage that causes shields; thoroughly solve under the power-frequency overvoltage stable state problem of the Explosion of on Arrester that causes because of protection gap tripping.
Description of drawings
Fig. 1 is the electrical schematic diagram of a kind of control gap of the present invention.
Fig. 2 is the electrical schematic diagram of the protective device of 110KV transformer neutral point of the present invention.
Fig. 3 is the structural representation of the protective device of 110KV transformer neutral point of the present invention.
Fig. 4 is the structural representation of a kind of control gap of the present invention.
Embodiment
Embodiment one: referring to Fig. 1 and Fig. 4 present embodiment is described, the described a kind of control gap of present embodiment, it comprises controlled flip-over type protection gap; Described controlled flip-over type protection gap forms unit 2 by overvoltage type identification and energy-storage units 1, trigger impulse and controlled discharge gap 3 is formed;
Described overvoltage type identification and energy-storage units 1 are by capacitor C
1, capacitor C
2, isolating transformer T
1, the lightning protection resistance R
1, full-wave rectification bridge D
1, the current-limiting protection resistance R
2Form with pulsed capacitance C,
Described trigger impulse forms unit 2 by high pressure diac D
2With pulse transformer T
2Form,
Described controlled discharge gap 3 is three electrode sphere gap switches, and described three electrode sphere gap switches comprise the first spheric electrode G
1, the second spheric electrode G
2With trigger electrode J; Capacitor C in described overvoltage type identification and the energy-storage units 1
1The a termination first spheric electrode G
1, described capacitor C
1The other end and capacitor C
2An end connect capacitor C
2Other end ground connection, described isolating transformer T
1Primary coil and capacitor C
2Be connected in parallel isolating transformer T
1One end of secondary coil and lightning protection resistance R
1An end connect isolating transformer T
1The other end of secondary coil and full-wave rectification bridge D
1AC signal input connect described full-wave rectification bridge D
1Another AC signal input and lightning protection resistance R
1The other end connect full-wave rectification bridge D
1Direct current cathode output end ground connection, full-wave rectification bridge D
1The direct-flow positive pole output simultaneously and the current-limiting protection resistance R
2The end of an end, pulsed capacitance C and trigger impulse form high pressure diac D in the unit 2
2Anode connects, described current-limiting protection resistance R
2The other end and the equal ground connection of the other end of pulsed capacitance C;
High pressure diac D
2Negative electrode and pulse transformer T
2An end of primary coil connect described pulse transformer T
2The other end ground connection of primary coil, described pulse transformer T
2An end of secondary coil be connected described pulse transformer T with trigger electrode J in the controlled discharge gap 3
2The other end ground connection of secondary coil;
The described second spheric electrode G
2Ground connection.
Embodiment two: referring to Fig. 1 and Fig. 4 present embodiment is described, the difference of present embodiment and embodiment one described a kind of control gap is, move for greater than 48KV the time in the power-frequency voltage value in described controlled discharge gap 3.
Embodiment three: referring to Fig. 1 and Fig. 4 present embodiment is described, the difference of present embodiment and embodiment one described a kind of control gap is, is failure to actuate for less than 146KV the time in the lightning impulse residual voltage in described controlled discharge gap 3.
Embodiment four: present embodiment is described referring to Fig. 1, Fig. 2, Fig. 3 and Fig. 4; present embodiment is the protective device that contains the 110KV transformer neutral point of embodiment one or two or three described a kind of control gaps; it comprises zinc oxide arrester MOA, control gap and 110KV transformer, the first spheric electrode G in the end of described zinc oxide arrester MOA and the controlled discharge gap 3
1All the neutral point with the 110KV transformer is connected, the capacitor C in the other end of described zinc oxide arrester MOA and overvoltage type identification and the energy-storage units 1
2The equal ground connection of the other end.
Embodiment five: present embodiment is described referring to Fig. 1, Fig. 2, Fig. 3 and Fig. 4; the difference of the protective device of present embodiment and embodiment four described 110KV transformer neutral points is; the lightning impulse residual voltage of described zinc oxide arrester MOA is 146KV, and the continuous power-frequency voltage value is for being less than or equal to 48KV.
Embodiment six: present embodiment is described referring to Fig. 1, Fig. 2, Fig. 3 and Fig. 4; present embodiment is to realize the guard method of 110KV transformer neutral point according to the protective device of embodiment four described 110KV transformer neutral points; its detailed process is
At first, by the identification of voltage type identification with 1 pair of overvoltage type of energy-storage units, obtain recognition result,
When recognition result is steady-state overvoltage, voltage type identification sends steady-state overvoltage to trigger impulse with energy-storage units 1 and forms unit 2, trigger impulse forms unit 2 and forms start pulse signal, and this start pulse signal is sent to controlled discharge gap 3,3 actions of controlled discharge gap realize the protection to the 110KV transformer neutral point;
When recognition result was temporary overvoltage, zinc oxide arrester MOA action realized the 110KV transformer neutral point is protected.
Voltage type identification sends temporary overvoltage with energy-storage units 1 and forms unit 2 to trigger impulse, and trigger impulse forms unit 2 can't form start pulse signal, is failure to actuate in controlled discharge gap 3.
Embodiment seven: present embodiment is described referring to Fig. 1, Fig. 2, Fig. 3 and Fig. 4; the difference of the guard method of present embodiment and embodiment six described 110KV transformer neutral points is; the lightning impulse residual voltage of described zinc oxide arrester MOA is 146KV, and the continuous power-frequency voltage value is for being less than or equal to 48KV.
Embodiment eight: present embodiment is described referring to Fig. 1, Fig. 2, Fig. 3 and Fig. 4; the difference of the guard method of present embodiment and embodiment six described 110KV transformer neutral points is, is failure to actuate for less than 146KV the time in the lightning impulse residual voltage in described controlled discharge gap 3.
Embodiment nine: present embodiment is described referring to Fig. 1, Fig. 2, Fig. 3 and Fig. 4; the difference of the guard method of present embodiment and embodiment six described 110KV transformer neutral points is, move for greater than 48KV the time in the power-frequency voltage value in described controlled discharge gap 3.
Embodiment ten: present embodiment is described referring to Fig. 1, Fig. 2, Fig. 3 and Fig. 4; the difference of the guard method of present embodiment and embodiment six described 110KV transformer neutral points is; be between 0 to 5ms the action time of described temporary overvoltage, and amplitude is the megavolt level.
Concrete mode 11: present embodiment is described referring to Fig. 1, Fig. 2, Fig. 3 and Fig. 4; the difference of the guard method of present embodiment and embodiment six described 110KV transformer neutral points is; be between 0 minute to 5 minutes the action time of described steady-state overvoltage, and amplitude is that 0V is between the 73KV.
Claims (9)
1. a control gap is characterized in that, it comprises controlled flip-over type protection gap; Described controlled flip-over type protection gap forms unit (2) by overvoltage type identification and energy-storage units (1), trigger impulse and controlled discharge gap (3) are formed;
Described overvoltage type identification and energy-storage units (1) are by capacitor C
1, capacitor C
2, isolating transformer T
1, the lightning protection resistance R
1, full-wave rectification bridge D
1, the current-limiting protection resistance R
2Form with pulsed capacitance C,
Described trigger impulse forms unit (2) by high pressure diac D
2With pulse transformer T
2Form,
Described controlled discharge gap (3) is three electrode sphere gap switches, and described three electrode sphere gap switches comprise the first spheric electrode G
1, the second spheric electrode G
2With trigger electrode J; Capacitor C in described overvoltage type identification and the energy-storage units (1)
1The a termination first spheric electrode G
1, described capacitor C
1The other end and capacitor C
2An end connect capacitor C
2Other end ground connection, described isolating transformer T
1Primary coil and capacitor C
2Be connected in parallel isolating transformer T
1One end of secondary coil and lightning protection resistance R
1An end connect isolating transformer T
1The other end of secondary coil and full-wave rectification bridge D
1AC signal input connect described full-wave rectification bridge D
1Another AC signal input and lightning protection resistance R
1The other end connect full-wave rectification bridge D
1Direct current cathode output end ground connection, full-wave rectification bridge D
1The direct-flow positive pole output simultaneously and the current-limiting protection resistance R
2The end of an end, pulsed capacitance C and trigger impulse form high pressure diac D in the unit (2)
2Anode connects, described current-limiting protection resistance R
2The other end and the equal ground connection of the other end of pulsed capacitance C;
High pressure diac D
2Negative electrode and pulse transformer T
2An end of primary coil connect described pulse transformer T
2The other end ground connection of primary coil, described pulse transformer T
2An end of secondary coil be connected described pulse transformer T with trigger electrode J in controlled discharge gap (3)
2The other end ground connection of secondary coil;
The described second spheric electrode G
2Ground connection.
2. a kind of control gap according to claim 1 is characterized in that, move for greater than 48KV the time in the power-frequency voltage value in described controlled discharge gap (3).
3. a kind of control gap according to claim 1 is characterized in that, is failure to actuate for less than 146KV the time in the lightning impulse residual voltage in described controlled discharge gap (3).
4. the protective device that contains the 110KV transformer neutral point of claim 1 or 2 or 3 described a kind of control gaps; it is characterized in that; it comprises zinc oxide arrester MOA, control gap and 110KV transformer, the first spheric electrode G in the end of described zinc oxide arrester MOA and controlled discharge gap (3)
1All the neutral point with the 110KV transformer is connected, the capacitor C in the other end of described zinc oxide arrester MOA and overvoltage type identification and the energy-storage units (1)
2The equal ground connection of the other end.
5. the protective device of 110KV transformer neutral point according to claim 4 is characterized in that, the lightning impulse residual voltage of described zinc oxide arrester MOA is 146KV, and the continuous power-frequency voltage value is for being less than or equal to 48KV.
6. the protective device of 110KV transformer neutral point according to claim 4 is realized the guard method of 110KV transformer neutral point, it is characterized in that, its detailed process is,
At first, by voltage type identification and the identification of energy-storage units (1) to the overvoltage type, obtain recognition result,
When recognition result is steady-state overvoltage, voltage type identification sends steady-state overvoltage to trigger impulse with energy-storage units (1) and forms unit (2), trigger impulse forms unit (2) and forms start pulse signal, and this start pulse signal is sent to controlled discharge gap (3), controlled discharge gap (3) action realizes the protection to the 110KV transformer neutral point;
When recognition result was temporary overvoltage, zinc oxide arrester MOA action realized the 110KV transformer neutral point is protected.
7. the guard method of 110KV transformer neutral point according to claim 6 is characterized in that, the lightning impulse residual voltage of described zinc oxide arrester MOA is 146KV, and the continuous power-frequency voltage value is for being less than or equal to 48KV.
8. the guard method of 110KV transformer neutral point according to claim 6 is characterized in that, is failure to actuate for less than 146KV the time in the lightning impulse residual voltage in described controlled discharge gap (3).
9. the guard method of 110KV transformer neutral point according to claim 6 is characterized in that, move for greater than 48KV the time in the power-frequency voltage value in described controlled discharge gap (3).
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| CN2013102334197A CN103269058A (en) | 2013-06-13 | 2013-06-13 | Controllable gap, and device and method for protecting neutral point of 110KV transformer based on controllable gap |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106410748A (en) * | 2016-09-30 | 2017-02-15 | 深圳供电局有限公司 | Transformer neutral point protection device |
| CN110854809A (en) * | 2019-11-11 | 2020-02-28 | 深圳供电局有限公司 | Detection method of transformer neutral point protection device and protection device |
| CN111030049A (en) * | 2019-11-19 | 2020-04-17 | 深圳供电局有限公司 | Transformer neutral point protection method and device |
| CN113783172A (en) * | 2021-07-22 | 2021-12-10 | 西安交通大学 | Intelligent combined protection assembly with external series triggering type overvoltage protection gap |
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| 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 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110854809B (en) * | 2019-11-11 | 2022-04-26 | 深圳供电局有限公司 | Detection method of transformer neutral point protection device and protection device |
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| CN113783172A (en) * | 2021-07-22 | 2021-12-10 | 西安交通大学 | Intelligent combined protection assembly with external series triggering type overvoltage protection gap |
| CN113783172B (en) * | 2021-07-22 | 2023-08-01 | 西安交通大学 | Intelligent combined protection assembly with external string triggering overvoltage protection gap |
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Application publication date: 20130828 |