CN101286636B - Switching overvoltage absorption apparatus - Google Patents
Switching overvoltage absorption apparatus Download PDFInfo
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- CN101286636B CN101286636B CN2008100182748A CN200810018274A CN101286636B CN 101286636 B CN101286636 B CN 101286636B CN 2008100182748 A CN2008100182748 A CN 2008100182748A CN 200810018274 A CN200810018274 A CN 200810018274A CN 101286636 B CN101286636 B CN 101286636B
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Abstract
The invention discloses a switching overvoltage absorbing device, which consists of a vacuum protection switch which is connected with the hurl-slices controlling switch of an electrical device to be protected in a parallel way and a pressure-sensing element; the vacuum protection switch is a vacuum load switch or a vacuum contactor. The device has simple structure, convenient operation, high reliability and no maintenance, can effectively restrict and absorb the overvoltage produced by the electrification and the interruption of power supply of various electrical devices and power supply network; the device withdraws from the connection with the power supply network after the electrical devices finish the transitional process, the electrification and the interruption of power supply; the switching overvoltage absorbing device has more sensitive and reliable protection performance and longer service life, which causes the great reduction of the peak value of overvoltage sustained by the electrical devices to be protected, leads the electrical devices to be protected to avoid the damage by high power overvoltage or greatly reduces times of overvoltage sustained and effectively protects the safe operation of the electrical devices.
Description
Technical field
The present invention relates to a kind of overvoltage protection, especially relate to the switching overvoltage absorption apparatus in a kind of switching electricity operating process that is applicable to electric equipment and power supply grid.
Background technology
In electric power system, the useful life of various electric equipments with and the fail safe of operation separately be two important indicators that ensure electric power system and production safety.And in the normal use of qualified electric equipment, two factors that these two indexs are had the greatest impact are: 1) overvoltage; 2) overcurrent.Overvoltage is divided into Lightning Over-voltage and switching overvoltage again, and switching overvoltage is again the most frequent and heavier to the equipment safety operation harm factor of occurrence number.At present, vacuum circuit-breaker, vacuum load switch, vacuum contactor, vacuum analyzer and vacuum recloser equal vacuum switchgear are because of advantages such as its volume is little, in light weight, high-performance, high reliability, convenient, the suitable frequent operations of maintenance test, therefore captured market rapidly, all obtained using widely in every field.But vacuum switchgear is because its arc extinguishing ability is strong especially, therefore when cut-offfing load such as motor, transformer, reactor and capacitor, cause cut-off overvoltage, the asynchronous overvoltage of cut-offfing of overvoltage and three-phase of restriking repeatedly easily, along with the enhancing of stability and safety power supply importance, require strict further to improving system reliability.
Presently used overvoltage protection is with lightning arrester (comprising zinc oxide arrester) product, and its protective value and useful life all are that the size by chargeability decides.Because lightning arrester is attempted by on the power supply netting twine for a long time, add the characteristic of its valve block resistance, thereby, always there is the leakage current of about 1mA to flow through valve block, will produce certain operating temperature then.In the practice, if then protective value is good for the height of chargeability choosing, but the heat that frequent movement produced can reduce the useful life of lightning arrester again greatly, and the Explosion of on Arrester of damaging can further influence the safe operation of electric power system; If then protective value is poor for chargeability choosing low, can not protect electric equipment effectively, like this, it is bigger that main electric equipment damages the loss that enterprise and electric power system are caused.To sum up; in order to take into account above-mentioned two aspects simultaneously; existing lightning arrester all selects working voltage and switching impulse residual voltage value than higher mostly; usually the power-frequency sparkover voltage of lightning arrester is more than 2.3 times of protected electric equipment rated operational voltage; and switching impulse sparkover voltage is 3～3.5 times of protected electric equipment rated operational voltage; even like this, the overvoltage that is produced still has harm to protected electric equipment.At present, a large amount of high-voltage electrical equipments is all arranged every year, switching overvoltage is damaged or shorten useful life because of not bearing.At present, industrial and mining enterprises are mostly with the main switch element of vacuum circuit-breaker as the various electrical appliance equipment of break-make, when vacuum circuit-breaker has the electric equipment of energy storage characteristic at switching, as no-load transformer, reactor, capacitor group, nonloaded line, motor etc., the characteristics of the switching overvoltage that is produced are: very short from producing regression time, and only several milliseconds to tens milliseconds; The overvoltage and vacuum switch is restriked, magnitude of voltage can be higher, and the time can be longer.
Summary of the invention
Technical problem to be solved by this invention is at above-mentioned deficiency of the prior art; a kind of switching overvoltage absorption apparatus is provided; it is simple in structure, easy to operate, reliability is high and non-maintaining; making protected electric equipment bear superpotential peak value reduces significantly; bear the superpotential number of times of high power and also significantly reduce, can effectively protect the safe operation of electric equipment.
For solving the problems of the technologies described above; the technical solution used in the present invention is: a kind of switching overvoltage absorption apparatus; it is characterized in that: by successively with the switching control switch of protected electric equipment mutually and the vacuum protection switch and the pressure cell that connect connect to form, described vacuum protection switch is vacuum load switch or vacuum contactor.
Described vacuum protection switch is the control switch that the energy automatic time delay disconnects, and the on/off switch control loop of its switching control loop and described switching control switch is formed an interlock circuit.
Described switching control loop is made up of closing circuit and automatic time delay sub-gate circuit; Described switching control loop is provided with two auxiliary contact of often opening, and it is serially connected in respectively in the on/off switch control loop of described switching control switch.
Described vacuum contactor is the three-phase vacuum contactor, and the quantity of described pressure cell is three, and three pressure cells join with A, B, the C three-phase leading-out terminal of vacuum contactor respectively.
Three single-phase vacuum contactors of described vacuum contactor include case, and the vacuum switch tube, conducting rod, cylinder lever connecting rod, connecting rod and the control board that connect the portion that also sets within it successively from top to bottom; The outside of described connecting rod is set with spring; The inner chamber of described case is divided into two parts up and down, and its underpart is the ancillary apparatus chamber;
Three control boards of described vacuum contactor link to each other successively, and it is indoor all to be positioned at same ancillary apparatus; One of them control board is provided with switching winding and the closing coil that vacuum contactor is controlled, and also is provided with the control button that all joins with switching winding and closing coil on the described case, also is provided with tripping spring between described control button and control board; Be respectively arranged with the auxiliary contact switch on two other control board.
On the described conducting rod metal is installed and is flexible coupling, described metal is flexible coupling and guide plate joins; Described pressure cell is installed between guide plate and the outlet guide plate one, and outlet guide plate one ground connection and its are positioned at the guide plate below; The upper outer of described case also is provided with the outlet guide plate two that joins with vacuum switch tube, and outlet guide plate two joins with the switching control switch of protected electric equipment.
Described metal is flexible coupling and is the busbar that is flexible coupling.
Described outlet guide plate one is rack-mount, and described support is fixed on the case outside.
Described two auxiliary contact of often opening are controlled by the auxiliary contact switch respectively; The delay time of described automatic time delay sub-gate circuit is in the 10-30s behind the described switching control switch deciliter.
Described pressure cell is the zinc oxide pressure-sensitive element.
The present invention compared with prior art has the following advantages, and 1, simple in structure, easy to connect, and easy and simple to handle; 2, reliability high and not oil-filled, do not fill vapour, non-maintaining; 3, the control performance with electric equipment matches with the protective value of zinc oxide pressure-sensitive element, adopt automatically controlled mode break-make its with being connected of electrical network and protected electric equipment, when overvoltage appears in electric equipment, with overvoltage Limiting at lower overvoltage level; And finish the transient process of break-make at electric equipment after, withdraw from again and being connected of electrical network, the zinc oxide pressure-sensitive element just not has leakage current and passes through when not working like this, and the valve block temperature reduces, material property has obtained good recovery, thereby makes the life-span of pressure cell improve a lot; 4, applied widely, to electric equipments such as the transformer in the electric power systems such as 6KV, 10kv, 35kv, 110kv, 220kv, 500kv, reactor, capacitor group, nonloaded line, motor, good protective effect is arranged all; 5, economic benefit height, industrial and mining enterprises' electricity supply and use equipment is behind configuration the present invention, and protected electric equipment bears superpotential multiple and only uses the zinc oxide pressure-sensitive elements can reduce by 60% than at present; In addition, all follow superpotential size closely related with the cost of insulating material the useful life of electric equipment, if the overvoltage during the electric equipment operation obviously reduces, the cost of used insulating material just can reduce when electric equipment was produced, can reduce the material cost of producing electric equipment, the fail safe of electric power system operation simultaneously also improves greatly, business electrical equipment damages the loss that causes because of overvoltage also can be significantly less, especially using in a large number under the situation of superhigh pressure electrical equipment equipment at present, adopting the present invention to have tangible economic benefit.To sum up; the present invention can effectively limit and absorb the overvoltage that various electric equipments produce when operating with the switching electricity of power supply grid; its protective value is sensitiveer reliable; longer service life; making protected electric equipment bear superpotential peak value reduces significantly; protected electric equipment can be avoided the superpotential injury of high power or bear superpotential number of times and greatly also reduce, and has protected the safe operation of electric equipment effectively.
Below by drawings and Examples, technical scheme of the present invention is described in further detail.
Description of drawings
Fig. 1 is a structural representation of the present invention.
Fig. 2 is the right view of Fig. 1.
The main circuit diagram that Fig. 3 is connected with vacuum circuit-breaker for the present invention.
Fig. 4 is the circuit theory diagrams of vacuum circuit-breaker control loop among Fig. 3.
Fig. 5 is the circuit theory diagrams of vacuum contactor switching control loop among Fig. 3.
Description of reference numerals:
1-outlet guide plate one; The 2-support; 3-zinc oxide pressure-sensitive element;
The 4-busbar that is flexible coupling; 5-outlet guide plate two; The 6-vacuum switch tube;
The 7-cylinder lever connecting rod; The 8-case; 9-auxiliary contact switch;
10-ancillary apparatus chamber; The 11-switching winding; The 12-closing coil;
The 13-bolt; The 14-conducting rod; The 15-spring;
The 16-control board; The 17-tripping spring; The 18-control button;
The 19-connecting rod; The 20-guide plate; The 21-vacuum contactor.
Embodiment
As shown in Figure 3, the present invention by with the switching control switch of protected electric equipment mutually and the vacuum protection switch and the pressure cell that connect form, described vacuum protection switch is a vacuum contactor 21.In this embodiment, described vacuum contactor 21 is the three-phase vacuum contactor, and the quantity of its pressure cell is three, and three pressure cells join with A, B, the C three-phase leading-out terminal of vacuum contactor 21 respectively.Wherein, the switching control switch of protected electric equipment is that its high-tension switch cabinet is vacuum circuit-breaker DL; protected electric equipment is the electric equipment with energy storage characteristic, and promptly the power supply grid of 3～10kv connects power capacitor reactive compensation installation after by vacuum circuit-breaker DL, current transformer LH.Described vacuum contactor 21 joins with vacuum circuit-breaker DL, and described pressure cell is a zinc oxide pressure-sensitive element 3, and an end and the vacuum contactor 21 of its zinc oxide pressure-sensitive element 3 join other end ground connection.In addition, the control switch that the vacuum contactor 21 that is adopted disconnects for the energy automatic time delay, the on/off switch control loop that its switching control loop and described switching control switch are vacuum circuit-breaker DL is formed an interlock circuit; The delay time of its automatic time delay sub-gate circuit is 10-30s, and promptly behind DL deciliter 10-30s of vacuum circuit breaker, vacuum contactor 21 can automatic disconnection behind time-delay 10-30s.In the practice, described vacuum protection switch also can be vacuum load switch, the control switch that it also can adopt non-automatic time-delay to disconnect; in the specific operation process; behind DL deciliter 10-30s of vacuum circuit breaker, disconnect by operation manually, thereby operation comparatively bothers.
As shown in Figure 1 and Figure 2, the three-phase vacuum contactor of described vacuum contactor 21 includes case 8, and the vacuum switch tube 6, conducting rod 14, cylinder lever connecting rod 7, connecting rod 19 and the control board 16 that connect the portion that also sets within it successively from top to bottom, the upper end of its conducting rod 14 and vacuum switch tube 6 join, and the outside of described connecting rod 19 is set with spring 15.The inner chamber of described case 8 is divided into two parts up and down, and its underpart is ancillary apparatus chamber 10, and wherein three of three-phase vacuum contactor 21 control boards 16 all are positioned at same ancillary apparatus chamber 10, and three 16 of control boards link to each other successively.
It is three switching winding 11 and closing coils 12 that the single-phase vacuum contactor is controlled that one of them control board 16 is provided with vacuum contactor 21, also be provided with the control button 18 that all joins with switching winding 11 and closing coil 12 on the described case 8,16 of this control button 18 and control boards also are provided with tripping spring 17, promptly should directly control break-make of the present invention by control button 18.Be respectively arranged with an auxiliary contact switch 9 on two other control board 16.
On the described conducting rod 14 metal is installed and is flexible coupling, this metal is flexible coupling and is the busbar 4 that is flexible coupling, and itself and guide plate 20 join.Described zinc oxide pressure-sensitive element 3 is installed between guide plate 20 and the outlet guide plate 1 by bolt 13 respectively, and be positioned at outlet guide plate one 1 ground connection of guide plate 20 belows, has just realized being connected between vacuum contactor 21 and the zinc oxide pressure-sensitive element 3 with this.In this embodiment, described outlet guide plate 1 is installed on the support 2, and described support 2 is fixed on case 8 outsides.In addition; the upper outer of described case 8 also is provided with the outlet guide plate 25 that joins with vacuum switch tube 6; outlet guide plate 25 joins with the switching control switch of protected electric equipment, realizes being connected of switching control switch of the present invention and protected electric equipment with this.
As Fig. 4, shown in Figure 5, vacuum contactor 21 of the present invention is the control switch that the energy automatic time delay disconnects, and its switching control loop is made up of closing circuit and automatic time delay sub-gate circuit; And its switching control loop also is provided with three auxiliary contact CJ2, the CJ3, the CJ4 that often open, two auxiliary contact CJ3 and CJ4 that often open wherein, in the on/off switch control loop that to be serially connected in described switching control switch respectively be vacuum circuit-breaker DL, thereby make the switching control loop of vacuum contactor 21 and the on/off switch control loop that described switching control switch is vacuum circuit-breaker DL form an interlock circuit.Described two auxiliary contact CJ3, CJ4 that often open are controlled by auxiliary contact switch 9 respectively.Like this, when this switching overvoltage absorption apparatus is not devoted oneself to work, be before vacuum contactor 21 is not catered to, high-tension switch cabinet is that vacuum circuit-breaker DL can not carry out deciliter switching work, when having only this switching overvoltage absorption apparatus not devote oneself to work, vacuum circuit-breaker DL can carry out deciliter switching work.
And the closing circuit of vacuum contactor 21 is composed in series successively by the control coil CJ of automatic switch QA, normally-closed contact 1CJ and vacuum contactor; Described automatic time delay sub-gate circuit is composed in series by an auxiliary contact CJ2 who often opens and time-delay relay SJ, and the delay time of described time-delay relay SJ is in the 10-30s after described vacuum circuit-breaker DL deciliter.In this embodiment, the delay time of its time-delay relay SJ is 30s, promptly behind vacuum circuit-breaker DL deciliter 30s, and vacuum contactor 21 automatic disconnection again.That is to say, be after vacuum circuit-breaker DL carries out deciliter switching work at high-tension switch cabinet, and after promptly protected electric equipment was disconnected, energising finishes, the corresponding again control the present invention of the automatic time delay sub-gate circuit of vacuum contactor 21 was out of service automatically behind time-delay 30s.
The course of work of the present invention is: before using, at first the switching control loop of vacuum contactor 21 and the on/off switch control loop of described switching control switch are formed an interlock circuit, often open auxiliary contact CJ3 and CJ4 for two that are about to its switching control loop, in the on/off switch control loop that to be serially connected in described switching control switch respectively be vacuum circuit-breaker DL.
In use of the present invention; earlier produce the discharge voltage value that superpotential different qualities is determined zinc oxide pressure-sensitive element 3, limit the time of zinc oxide pressure-sensitive element 3 and electrical network connection again by vacuum contactor 21 and switching control loop thereof according to protected electric equipment.Before logical (breaking) electricity of protected electric equipment, cater to vacuum contactor 21 of the present invention earlier, the switching control switch that closes protected electric equipment again is vacuum circuit-breaker DL.Then when closing ignition distributor equipment, no matter following which kind of overvoltage appears: the 1. overvoltage that produces of electrical equipment switching transient process; 2. the overvoltage of the asynchronous generation of three-phase contact; 3. the switch overvoltage that produces etc. of restriking promptly when the overvoltage of the end of incoming cables appearances 〉=1.5Ue of electric equipment, so just can be passed through the discharge of zinc oxide pressure-sensitive element 3 ground connection, make protected electric equipment be effectively protected; And after electric equipment power on/off process finished, this switching overvoltage absorption apparatus was out of service automatically by its automatic time delay sub-gate circuit time-delay 30 seconds again.That is to say, when overvoltage appears in electric equipment, with overvoltage Limiting at lower overvoltage level; And finish the transient process of break-make at electric equipment after, withdraw from again and being connected of electrical network, zinc oxide pressure-sensitive element 3 just not has leakage current and passes through when not working like this, and the valve block temperature reduces, material property has obtained good recovery, thereby makes the life-span of pressure cell improve a lot.
The above; it only is preferred embodiment of the present invention; be not that the present invention is imposed any restrictions, everyly any simple modification that above embodiment did, change and equivalent structure changed, all still belong in the protection range of technical solution of the present invention according to the technology of the present invention essence.
Claims (8)
1. switching overvoltage absorption apparatus, it is characterized in that: by successively with the switching control switch of protected electric equipment mutually and the vacuum protection switch and the pressure cell that connect connect to form, described vacuum protection switch is vacuum load switch or vacuum contactor (21), described vacuum protection switch is the control switch that the energy automatic time delay disconnects, the on/off switch control loop of its switching control loop and described switching control switch is formed an interlock circuit, and it is characterized in that: described switching control loop is made up of closing circuit and automatic time delay sub-gate circuit; Described switching control loop is provided with two auxiliary contact of often opening, and it is serially connected in respectively in the on/off switch control loop of described switching control switch.
2. according to the described switching overvoltage absorption apparatus of claim 1, it is characterized in that: described vacuum contactor (21) is the three-phase vacuum contactor, the quantity of described pressure cell is three, and three pressure cells join with A, B, the C three-phase leading-out terminal of vacuum contactor (21) respectively.
3. according to the described switching overvoltage absorption apparatus of claim 2, it is characterized in that: three single-phase vacuum contactors of described vacuum contactor (21) include case (8), and the vacuum switch tube (6), conducting rod (14), cylinder lever connecting rod (7), connecting rod (19) and the control board (16) that connect the portion that also sets within it successively from top to bottom; The outside of described connecting rod (19) is set with spring (15); The inner chamber of described case (8) is divided into two parts up and down, and its underpart is ancillary apparatus chamber (10);
Three control boards (16) of described vacuum contactor (21) link to each other successively, and all are positioned at same ancillary apparatus chamber (10); One of them control board (16) is provided with switching winding (11) and the closing coil (12) that vacuum contactor (21) is controlled, also be provided with the control button (18) that all joins with switching winding (11) and closing coil (12) on the described case (8), also be provided with tripping spring (17) between a described control button (18) and a described control board (16); Be respectively arranged with auxiliary contact switch (9) on two other control board (16).
4. according to the described switching overvoltage absorption apparatus of claim 3, it is characterized in that: on the described conducting rod (14) metal is installed and is flexible coupling, described metal is flexible coupling and guide plate (20) joins; Described pressure cell is installed between guide plate (20) and the outlet guide plate one (1), and outlet guide plate one (1) ground connection and its are positioned at guide plate (20) below; The outlet guide plate two (5) that the upper outer of described case (8) also is provided with and vacuum switch tube (6) joins, outlet guide plate two (5) joins with the switching control switch of protected electric equipment.
5. according to the described switching overvoltage absorption apparatus of claim 4, it is characterized in that: described metal is flexible coupling and is the busbar that is flexible coupling (4).
6. according to the described switching overvoltage absorption apparatus of claim 4, it is characterized in that: described outlet guide plate one (1) is installed on the support (2), and described support (2) is fixed on case (8) outside.
7. according to the described switching overvoltage absorption apparatus of claim 1, it is characterized in that: described two auxiliary contact of often opening are controlled by auxiliary contact switch (9) respectively; The delay time of described automatic time delay sub-gate circuit is in the 10-30s behind the described switching control switch deciliter.
8. according to the described switching overvoltage absorption apparatus of claim 1, it is characterized in that: described pressure cell is zinc oxide pressure-sensitive element (3).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2008100182748A CN101286636B (en) | 2008-05-23 | 2008-05-23 | Switching overvoltage absorption apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2008100182748A CN101286636B (en) | 2008-05-23 | 2008-05-23 | Switching overvoltage absorption apparatus |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101286636A CN101286636A (en) | 2008-10-15 |
| CN101286636B true CN101286636B (en) | 2010-06-09 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2008100182748A Expired - Fee Related CN101286636B (en) | 2008-05-23 | 2008-05-23 | Switching overvoltage absorption apparatus |
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| Country | Link |
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| CN (1) | CN101286636B (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1055443A (en) * | 1990-02-27 | 1991-10-16 | Gec阿尔斯托姆有限公司 | Line-breaker with variable resistor backup shutdoun |
| CN2148383Y (en) * | 1993-02-03 | 1993-12-01 | 徐正敏 | Electronic non-arcing controller for contactor |
| CN2359792Y (en) * | 1999-02-08 | 2000-01-19 | 刘华民 | Active arc-control device |
| CN201191545Y (en) * | 2008-05-23 | 2009-02-04 | 卢为忠 | Switching overvoltage absorption apparatus |
-
2008
- 2008-05-23 CN CN2008100182748A patent/CN101286636B/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1055443A (en) * | 1990-02-27 | 1991-10-16 | Gec阿尔斯托姆有限公司 | Line-breaker with variable resistor backup shutdoun |
| CN2148383Y (en) * | 1993-02-03 | 1993-12-01 | 徐正敏 | Electronic non-arcing controller for contactor |
| CN2359792Y (en) * | 1999-02-08 | 2000-01-19 | 刘华民 | Active arc-control device |
| CN201191545Y (en) * | 2008-05-23 | 2009-02-04 | 卢为忠 | Switching overvoltage absorption apparatus |
Non-Patent Citations (3)
| Title |
|---|
| JP特开2000-133099A 2000.05.12 |
| JP特开2002-75145A 2002.03.15 |
| JP特开平7-296684A 1995.11.10 |
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| CN101286636A (en) | 2008-10-15 |
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Granted publication date: 20100609 Termination date: 20140523 |