CN102684147B - Outdoor zero sequence protective net and guard method - Google Patents
Outdoor zero sequence protective net and guard method Download PDFInfo
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- CN102684147B CN102684147B CN201210079542.3A CN201210079542A CN102684147B CN 102684147 B CN102684147 B CN 102684147B CN 201210079542 A CN201210079542 A CN 201210079542A CN 102684147 B CN102684147 B CN 102684147B
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Abstract
The present invention relates to outdoor zero sequence protective net and guard method that a kind of outdoor study equipment can guarantee its operating personnel's personal safety in job area; be mainly used in outdoor building industry; in controller, the multiple power supplies output of main circuit is connected respectively with by the power input of protector; in controller, control loop signal end is connected with catch net by wire, and catch net is between protected object and object of protection.Advantage: one is that outdoor zero sequence protective net building course is safe and efficient, cost is low, can large area and hypervelocity build, security performance multi-ensuring (can select when protected equipment contact protection net protected device powers down shut down and high-voltage electric power circuit automatic trip, locking, start warning device simultaneously, only have and permit through safety manager the energising that could reset, convenient and safe management), reaction sensitivity is high, simple to operate, practical; Two is fall to make basis 90%, and work efficiency is high, and disposable examination is checked and accepted by safety supervision department.
Description
Technical field
The present invention relates to outdoor zero sequence protective net and guard method that a kind of outdoor study equipment can guarantee its operating personnel's personal safety in job area, be mainly used in outdoor building industry, belong to outdoor study equipment protection system and manufacture field.
Background technology
On current construction site; as long as the off-site of construction is with middle pressure overhead transmission line (as 10kV); middle pressure rack ceases to be busy is touched in order to prevent tower crane steel cable; according to Work Safety Supervision Bureau's requirement; must set up protective device between tower crane and overhead transmission line, object is in order to prevent the serious accident of pressing electric shock in tower crane generation beyond the mark.Such as: between tower crane on building sites and middle pressure rack ceases to be busy, set up a set of catch net, pressure rack ceases to be busy in preventing tower crane steel cable from directly contacting, causes life security incident.This protective device general steel pipe that adopts in structural design erects the protective frame come layer by layer.Its weak point: one is that this device construction duration is long, and cost is high, and minimum construction also in hundreds of thousands RMB, and exists certain potential safety hazard in building course; Two is that in use procedure, by wind impact is comparatively large, there is the hidden danger of collapsing.
Summary of the invention
Purpose of design: avoid the weak point in background technology, designs a kind of outdoor study equipment in job area and, during operation, can guarantee outdoor zero sequence protective net and the guard method of implement operating personnel personal safety.
Design: in order to realize above-mentioned purpose of design.1, main circuit annexation: main circuit adopts TN-S electric power system, and isolating switch upper end power supply is attracted by outside power distribution cabinet, and lower end, through A.C. contactor II main contact, three electric energy meters, three main circuit breakers, is connected to protected device circuit header tank.TN-S electric power system, protective wire (PE) line and working zero line (N) separately use, and special line is special, prevents the possibility that it breaks to the full extent, and main circuit breaker adopts zero-sequenceprotection switch, as carried out iterative earthing to protected equipment again.Only have when protective wire and iterative earthing line all break, have phase line leak electricity and the tripping of zero-sequenceprotection malfunctioning switch, personal contact to electric leakage equipment and formation current circuit, just can cause personal injury.2, control loop annexation: control loop power supply (L1, L2, L3) is after three fuses; L3 and working zero line (N) are after the zero-sequence transformer of two series connection, and working zero line (N) is connected to all control loop components and parts one end and is reliably connected with catch net.Control line L3 is connected to A.C. contactor I coil through stop button, start button, realizes start-up course.A.C. contactor I normally open contact I upper end power supply is attracted by stop button lower end; A.C. contactor I normally open contact I lower end causes A.C. contactor I coil; realize self-locking; cause A.C. contactor I normally open contact II again; elapsed time relay time delay disconnects normally closed interlock and is connected to auxiliary relay coil, time relay coil; isolation A.C. contactor I coil and auxiliary relay coil self-locking power supply, for fault noise reduction and power-off are shut down ready.L3 is connected to auxiliary relay coil and time relay coil through reset button, auxiliary relay normally open contact I, realizes auxiliary relay and time relay self-locking, ready to the fault noise reduction of fault alarm.L3 causes alarm through A.C. contactor I normally closed interlock, auxiliary relay contact II, realizes fault alarm function.L1, L2 are connected to A.C. contactor II coil through A.C. contactor I main contact, realize the startup of main circuit (A.C. contactor II main contact).Phase line L1, L2, L3 are connected to power supply indicator one end respectively, carry out charged display to main circuit.Control system is provided with open and close machine button (can realize remote activation/stopping), and fault power-off is shut down (only have remove fault could reset energising operation), outfit sound and light alarm and silencing function.Control loop adopts two former devices in series of zero-sequence current protection, and when preventing fault, the former device fault tripping of zero-sequence current protection, adds security reliability.3, Fig. 6 is zero-sequenceprotection schematic diagram.Its chief component is main switch, detects unsymmetrical current instrument transformer and release.Two wires exported by main switch simultaneously through ring-shaped core, then are connected to load.After main switch manual closing, unsymmetrical current Id=0, now contrary through the main circuit current I1 on ring-shaped core and I2 equal and opposite in direction, direction, I1+I2=0.The magnetic flux Φ 1 that two electric currents produce respectively in ring-shaped core and Φ 2 equal and opposite in direction, direction are contrary.The resultant flux Φ 1+ Φ 2=0 produced in iron core, therefore another secondary winding loop on instrument transformer ring-shaped core does not have induced voltage, U2=0, release is failure to actuate.When protected equipment touches catch net, produce zero-sequence current Id, Id=I1+I2, the resultant flux Φ=Φ 1+ Φ 2=Φ d now produced in ring-shaped core, then upper secondary winding loop unshakable in one's determination produces induced voltage U2.(namely electric current forms loop by the earth, creates zero-sequence current.This electric current flows back to without instrument transformer primary winding, destroys balance, so just have zero sequence fluxes in iron core, makes secondary coil export trip signal.) when zero-sequence current increases to predetermined numerical value (minimum be adjusted to 5mA), release action, the snap close of main switch is released and point deenergizing (break-time≤0.1s).
Technical scheme 1: outdoor zero sequence protective net; in controller, the multiple power supplies output of main circuit is connected respectively with by the power input of protector; in controller, control loop signal end is connected with catch net by wire, and catch net is between protected object and object of protection.
Technical scheme 2: the guard method of outdoor zero sequence protective net, (1) positive work often works: isolating switch closes a floodgate, protective circuit breaker I circuit breaker II closes a floodgate, A.C. contactor I coil obtains electric, the adhesive of A.C. contactor I contact, A.C. contactor II coil obtains electric, A.C. contactor II contact closure, multichannel main circuit breaker closes a floodgate, and external source electricity is powered respectively to by protector by isolating switch A.C. contactor II contact, electric energy meter and multichannel main circuit breaker; When being encountered catch net by protector; circuit breaker I and circuit breaker II are threaded off; A.C. contactor I coil losing electricity; the disjunction of A.C. contactor I contact; A.C. contactor II coil losing electricity; the disjunction of A.C. contactor II contact, main circuit outlet line has a power failure, thus plays protection by the object of protector.
Technical scheme 3: the guard method of outdoor zero sequence protective net, (1) positive work often works: isolating switch closes a floodgate, multichannel main circuit breaker combined floodgate, circuit breaker I and circuit breaker II close a floodgate, control button II 23 starts, A.C. contactor I coil obtains electric, the disjunction of A.C. contactor I normally closed interlock; 1. A.C. contactor I normally open contact and the adhesive of A.C. contactor I normally open contact II, A.C. contactor I self-locking, auxiliary relay coil obtains electric, time relay coil obtains electric, auxiliary relay contact I and auxiliary relay contact II adhesive, auxiliary relay and time relay self-locking, time relay contact disconnects; 2. A.C. contactor I main contact closes, and A.C. contactor II coil (3) obtains electric, A.C. contactor II contact closure; Stop button I 22 starts, and start button II 23 starts, and control button II 23 starts; (2) when fault occurs: circuit breaker I and circuit breaker II are threaded off, A.C. contactor I coil losing electricity, the disjunction of A.C. contactor I main contact; 1. A.C. contactor II coil losing electricity, the disjunction of A.C. contactor II contact, outlet line has a power failure; 2. A.C. contactor I normally closed interlock resets, and alarm starts, and reset button starts, Failure elimination.
Background technology of the present invention is compared, one is that outdoor zero sequence protective net building course is safe and efficient, cost is low, can large area and hypervelocity build, security performance multi-ensuring (protected device powers down can be selected to shut down when protected equipment contact protection net and high-voltage electric power circuit automatic trip, locking, start warning device simultaneously, only have and permit through safety manager the energising that could reset, convenient and safe management), reaction sensitivity is high, simple to operate, practical; Two is compared with background technology, and fall and make basis 90%, work efficiency is high, and disposable examination is checked and accepted by safety supervision department.
Accompanying drawing explanation
Fig. 1 is the block diagram of outdoor zero sequence protective net.
Fig. 2 is the circuit theory schematic diagram of controller (distribution box) the first embodiment.
Fig. 3 is the circuit theory schematic diagram of controller (distribution box) the second embodiment.
Fig. 4 is the block diagram of Fig. 1 and Fig. 2.
Fig. 5 is the block diagram of Fig. 1 and Fig. 3.
Fig. 6 is zero-sequenceprotection principle schematic.
Fig. 7 is Fig. 1 application schematic diagram.
Embodiment
Embodiment 1: with reference to accompanying drawing 1,2,4,6.A kind of outdoor zero sequence protective net; in controller 101, the multiple power supplies output of main circuit 4 is connected respectively with by the power input of protector 201; in controller 101, control loop 11 signal end is connected with catch net 301 by wire, and catch net 301 is between protected object 201 and object of protection 401
Described is tower crane by protector 201, tower crane of the prior art; Described protection object 401 is middle line ball, the overhead medium-pressure line near construction site.
Described catch net 301 zero line catch net and being made up of many exposed plain conductors.
In described main circuit 4, multichannel main circuit breaker (8,9,10) output connects protected device 201 respectively; multichannel main circuit breaker (8,9,10) input connects electric energy meter (5,6,7) one end respectively; electric energy meter (5,6, the 7) other end also connects A.C. contactor II contact 2 one end; in another termination isolating switch 1 output of A.C. contactor II contact 2 and controller 101, the phase line end (L1, L2, L3) of the three phase mains of control loop 11 connects, and isolating switch 1 inputs termination external power source.
In described control loop 11 three phase mains phase line end (L1, L2, L3) in L1, L2 be connected with A.C. contactor I contact 15 one end respectively; A.C. contactor I contact 15 other end forms loop by A.C. contactor II coil 3; zero line N and phase line L3 is connected with protective circuit breaker I 12 one end respectively; protective circuit breaker I 12 other end is connected with protective circuit breaker II 13 one end respectively, and protective circuit breaker II 13 other end is formed loop by A.C. contactor I coil 14 and is connected with catch net 301 by wire.
Embodiment 2: on the basis of embodiment 1, described electric energy meter (7,8, the 9) other end also connects air switch 501 one end, and air switch 501 connects Surge Protector 502 one end, Surge Protector 502 other end ground connection.
Embodiment 3: on the basis of embodiment 1 or 2, the guard method of outdoor zero sequence protective net, it is characterized in that: (1) positive work often works: isolating switch 1 closes a floodgate, protective circuit breaker I 12 circuit breaker II 13 closes a floodgate, A.C. contactor I coil 14 obtains electric, the adhesive of A.C. contactor I contact 15, A.C. contactor II coil 3 obtains electric, A.C. contactor II contact 2 closes, multichannel main circuit breaker (8, 9, 10) close a floodgate, external source electricity is by isolating switch 1 A.C. contactor II contact 2, electric energy meter (5, 6, 7) and multichannel main circuit breaker (8, 9, 10) power respectively to by protector 201, when being encountered catch net 301 by protector 201, circuit breaker I 12 and circuit breaker II 13 are threaded off, A.C. contactor I coil 14 dead electricity, the disjunction of A.C. contactor I contact 15, A.C. contactor II coil 3 dead electricity, the disjunction of A.C. contactor II contact 2, main circuit outlet line has a power failure, thus plays the object protecting protected device 201.
Embodiment 4: with reference to accompanying drawing 1,3,5,6.Outdoor zero sequence protective net, phase line end (the L1 of three phase mains in described control loop 11, L2, L3) L1 in, L2 is connected with A.C. contactor I main contact 29 one end respectively by fuse, A.C. contactor I main contact 29 other end forms loop by A.C. contactor II coil 3, zero line N and phase line L3 is connected with protective circuit breaker I 20 one end respectively, circuit breaker I 20 other end is connected with circuit breaker II 21 one end respectively, circuit breaker II 21 other end one (zero line N) connects catch net 301, other end (phase line L3) is connected with stop button I 22 one end, stop button I 22 other end is connected with start button II 23 one end and A.C. contactor I normally open contact I 26 one end, start button II 23 other end and A.C. contactor I coil 25 one end, A.C. contactor I normally open contact I 26 and A.C. contactor I normally open contact II 27 one end connect, A.C. contactor I coil 25 other end takes over control protecting wire net 301 respectively, power supply indicator (17 is connect by short circuit sheet 36, 18, 19) one end, auxiliary relay coil 30 other end, time relay coil 33 other end, another termination A.C. contactor I normally open contact II 27 one end of A.C. contactor I normally open contact 26, another termination time relay contact 34 one end of A.C. contactor I normally open contact II 27, another termination time relay coil 33 one end of time relay contact 34, auxiliary relay coil 30 one end, phase line L3 connects reset button 24 one end and A.C. contactor I normally closed interlock 28 one end, another termination auxiliary relay contact I 31 one end of reset button 24, another termination auxiliary relay coil 30 one end of auxiliary relay contact I 31 and time relay coil 33 one end, another termination auxiliary relay contact II 32 one end of A.C. contactor I normally closed interlock 28.
Embodiment 5: on the basis of embodiment 4, described auxiliary relay contact II 32 other end device 35 taking alarm one end, another termination circuit breaker II 21 other end one (zero line N) of alarm 35.
Embodiment 6: on the basis of embodiment 4 or 5, the guard method of outdoor zero sequence protective net,
(1) normally work: isolating switch 1 closes a floodgate, multichannel main circuit breaker (10,11,12) combined floodgate, circuit breaker I 20 and circuit breaker II 21 close a floodgate, control button II 23 starts, A.C. contactor I coil 25 obtains electric, the disjunction of A.C. contactor I normally closed interlock 28; 1. A.C. contactor I normally open contact 26 and the adhesive of A.C. contactor I normally open contact II 27, A.C. contactor I self-locking, auxiliary relay coil 30 electric, the time relay (33) electric, auxiliary relay contact I 31 and auxiliary relay contact II 32 adhesive, auxiliary relay self-locking, time relay contact 34 disconnects, and stop button I 22 starts, and start button II 23 starts; 2. A.C. contactor I main contact 29 closes, and A.C. contactor II coil 3 obtains electric, and A.C. contactor II contact 2 closes;
(2) when fault occurs: circuit breaker I 20 and circuit breaker II 21 are threaded off, A.C. contactor I coil 25 dead electricity, the disjunction of A.C. contactor I main contact 29; 1. A.C. contactor II coil 3 dead electricity, the disjunction of A.C. contactor II contact 2, outlet line has a power failure; 2. A.C. contactor I normally closed interlock 28 resets, and alarm 35 starts, and reset button 24 starts, Failure elimination.
It is to be understood that: although above-described embodiment to be contrasted detailed text description to mentality of designing of the present invention; but these text descriptions; just the simple text of mentality of designing of the present invention is described; instead of the restriction to mentality of designing of the present invention; any do not exceed mentality of designing of the present invention combination, increase or amendment, all fall within the scope of protection of the present invention.
Claims (8)
1. an outdoor zero sequence protective net, it is characterized in that: in controller (101), the multiple power supplies output of main circuit (4) is connected respectively with by the power input of protector (201), in controller (101), control loop (11) signal end is connected with catch net (301) by wire, and catch net (301) is positioned at by between protector (201) and object of protection (401); In described main circuit (4), multichannel main circuit breaker (8-10) output connects by protector (201) respectively, three main circuit breaker (8-10) inputs connect three electric energy meter (5-7) one end respectively, three electric energy meter (5-7) other ends also connect A.C. contactor II contact (2) one end, phase line end L1, L2, L3 of the three phase mains of another termination isolating switch (1) output of A.C. contactor II contact (2) and the middle control loop (11) of controller (101), isolating switch (1) input termination external power source.
2. outdoor zero sequence protective net according to claim 1, is characterized in that: be tower crane by protector (201); Object of protection (401) is middle line ball.
3. outdoor zero sequence protective net according to claim 1, is characterized in that: catch net (301) for zero line catch net and zero line catch net be made up of many exposed plain conductors.
4. outdoor zero sequence protective net according to claim 1; it is characterized in that: described A.C. contactor I comprises two pairs of contacts; phase line end L1, L2 of three phase mains connect A.C. contactor I two pairs of contact one end separately respectively; these the two pairs of contacts separately other end form loop by A.C. contactor II coil (3); protective circuit breaker I comprises two pairs of contacts; zero line N and phase line L3 is connected one end separately with two pairs of contacts of protective circuit breaker I respectively, and these the two pairs of contacts separately other end form loop by A.C. contactor I coil (14).
5. outdoor zero sequence protective net according to claim 1, it is characterized in that: described A.C. contactor I comprises two pairs of contacts, L1, L2 connects this two pairs of contact one end separately respectively by fuse, these the two pairs of contacts separately other end form loop by A.C. contactor II coil (3), protective circuit breaker I and circuit breaker II comprise two pairs of contacts, zero line N and phase line L3 is connected with one end separately, two pairs of contacts of protective circuit breaker I respectively, two pairs of contacts other end separately of this protective circuit breaker I is connected with one end separately, circuit breaker II two pairs of contacts respectively, another termination catch net (301) of the contact of connecting to neutral line N in circuit breaker II two pairs of contacts, the other end of the contact of phase-connecting wire L3 is connected with stop button I (22) one end, stop button I (22) other end is connected with start button II (23) one end and A.C. contactor I normally open contact I (26) one end, start button II (23) other end is connected with A.C. contactor I coil (25) one end and A.C. contactor I normally open contact I (26) other end, another termination catch net (301) of A.C. contactor I coil (25), auxiliary relay coil (30) other end, time relay coil (33) other end, another termination A.C. contactor I normally open contact II (27) one end of A.C. contactor I normally open contact I (26), another termination time relay contact (34) one end of A.C. contactor I normally open contact II (27), another termination time relay coil (33) one end of time relay contact (34), phase line L3 connects reset button (24) one end and A.C. contactor I normally closed interlock (28) one end, another termination auxiliary relay contact I (31) one end of reset button (24), another termination auxiliary relay coil (30) one end of auxiliary relay contact I (31), auxiliary relay coil (30) one end is connected with time relay coil (33) one end, another termination auxiliary relay contact II (32) one end of A.C. contactor I normally closed interlock (28).
6. outdoor zero sequence protective net according to claim 5, is characterized in that: described auxiliary relay contact II (32) other end device taking alarm (35) one end, another termination catch net (301) of alarm (35).
7. the guard method of an outdoor zero sequence protective net as claimed in claim 5, it is characterized in that: normally work: isolating switch (1) closes a floodgate, protective circuit breaker I (12) circuit breaker II (13) closes a floodgate, A.C. contactor I coil (14) obtains electric, two pairs of contacts (15) adhesive of A.C. contactor I, A.C. contactor II coil (3) obtains electric, A.C. contactor II contact (2) adhesive, multichannel main circuit breaker (8-10) closes a floodgate, external power source is by isolating switch (1), A.C. contactor II contact (2), electric energy meter (5-7) and multichannel main circuit breaker (8-10) are powered respectively to by protector (201), when being encountered catch net (301) by protector (201), circuit breaker I (12) and circuit breaker II (13) are threaded off, A.C. contactor I coil (14) dead electricity, two pairs of contacts (15) disjunction of A.C. contactor I, A.C. contactor II coil (3) dead electricity, A.C. contactor II contact (2) disjunction, main circuit outlet line has a power failure, thus plays protection by the object of protector (201).
8. a guard method for outdoor zero sequence protective net as claimed in claim 5, is characterized in that:
Normal work:
Isolating switch (1) closes a floodgate, multichannel main circuit breaker (10-12) combined floodgate, circuit breaker I (20) and circuit breaker II (21) close a floodgate, start button II (23) starts, A.C. contactor I coil (25) obtains electric, A.C. contactor I normally closed interlock (28) disjunction; 1. A.C. contactor I normally open contact I (26) and A.C. contactor I normally open contact II (27) adhesive, A.C. contactor I self-locking, auxiliary relay coil (30) electric, the time relay (33) coil obtains electric, auxiliary relay contact I (31) and auxiliary relay contact II (32) adhesive, auxiliary relay and time relay self-locking, time relay contact (34) disconnects, 2. A.C. contactor I two pairs of main contacts (29) adhesive, A.C. contactor II coil (3) obtains electric, A.C. contactor II contact (2) adhesive;
When fault occurs:
Circuit breaker I (20) and circuit breaker II (21) are threaded off, A.C. contactor I coil (25) dead electricity, the disjunction of A.C. contactor I two pairs of main contacts (29); 1. A.C. contactor II coil (3) dead electricity, A.C. contactor II contact (2) disjunction, outlet line has a power failure; 2. A.C. contactor I normally closed interlock (28) resets, and alarm (35) starts, and reset button (24) starts, Failure elimination.
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| CN201210079542.3A CN102684147B (en) | 2012-03-23 | 2012-03-23 | Outdoor zero sequence protective net and guard method |
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| CN201210079542.3A CN102684147B (en) | 2012-03-23 | 2012-03-23 | Outdoor zero sequence protective net and guard method |
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| CN102684147B true CN102684147B (en) | 2015-12-02 |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN201634326U (en) * | 2010-04-19 | 2010-11-17 | 韶关市丰一工贸有限公司 | Safety control device for crane |
| CN202817701U (en) * | 2012-03-23 | 2013-03-20 | 杭州中大电器承装有限公司 | An outdoor zero sequence protecting net system |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| JP4761778B2 (en) * | 2005-01-20 | 2011-08-31 | 中国電力株式会社 | Approach warning device |
| US8953295B2 (en) * | 2008-12-19 | 2015-02-10 | Iep2 Research Pty Limited | Protection system for an IT electrical distribution system having a floating reference conductor |
| JP2011151939A (en) * | 2010-01-21 | 2011-08-04 | Chugoku Electric Power Co Inc:The | Sag adjusting device for protective wire |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201634326U (en) * | 2010-04-19 | 2010-11-17 | 韶关市丰一工贸有限公司 | Safety control device for crane |
| CN202817701U (en) * | 2012-03-23 | 2013-03-20 | 杭州中大电器承装有限公司 | An outdoor zero sequence protecting net system |
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