CN107819325A - The three phases un identical protection device of breaker fail protection can be started - Google Patents
The three phases un identical protection device of breaker fail protection can be started Download PDFInfo
- Publication number
- CN107819325A CN107819325A CN201711176183.2A CN201711176183A CN107819325A CN 107819325 A CN107819325 A CN 107819325A CN 201711176183 A CN201711176183 A CN 201711176183A CN 107819325 A CN107819325 A CN 107819325A
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- breaker
- normally opened
- auxiliary contact
- loop
- protection
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- 230000008030 elimination Effects 0.000 abstract description 2
- 238000003379 elimination reaction Methods 0.000 abstract description 2
- 238000010276 construction Methods 0.000 abstract 1
- 230000005611 electricity Effects 0.000 description 4
- 238000005457 optimization Methods 0.000 description 2
- 238000012795 verification Methods 0.000 description 2
- 230000007812 deficiency Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 235000013399 edible fruits Nutrition 0.000 description 1
- 238000000034 method Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency 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
- H02H7/26—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency 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
- H02H7/22—Emergency 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 distribution gear, e.g. bus-bar systems; for switching devices
- H02H7/222—Emergency 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 distribution gear, e.g. bus-bar systems; for switching devices for switches
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- Keying Circuit Devices (AREA)
Abstract
The present invention relates to breaker three phases un identical protection technical field, it is a kind of three phases un identical protection device that can start breaker fail protection, it includes defencive function and realizes loop and protection act outlet loop, defencive function realizes that loop includes the normally opened auxiliary contact of negative sequence current relay and time-delay relay coil, split-phase circuit breaker position combined loop, together with the normally opened auxiliary contact of negative sequence current relay are sequentially connected in series with time-delay relay coil, protection act outlet loop includes the normally opened auxiliary contact of time-delay relay and outlet actuating relay, outlet the first normally opened auxiliary contact of actuating relay electrically connect with circuit breaker mechanism case, outlet the second normally opened auxiliary contact of actuating relay electrically connect with circuit-breaker failure portection equipment.The present invention is simple in construction, is sent but during breaker tripping in three phases un identical protection action, can start breaker fail protection, and all intervals on operation bus, ensure the reliable elimination of failure where tripping circuit breaker.
Description
Technical field
It is that a kind of can start the three of breaker fail protection the present invention relates to breaker three phases un identical protection technical field
Phase non-uniform protection device.
Background technology
The power plant and power network of 220kV and above at present, more to use split-phase breaker, split-phase breaker occurs
Three phases un identical protection generally uses breaker body three phases un identical protection, breaker body three-phase during unbalanced three-phase lines state
Non-uniform protection is protected for switching value, and switching value time of return is slower, can not meet to start breaker fail protection requirement, and then
It is difficult to start breaker fail protection after three phases un identical protection acts, therefore can occurs to work as breaker unbalanced three-phase lines
Protection act and breaker tripping cause non-three phase state to be run, and can not start breaker fail protection, failure can not be removed
Situation.
The content of the invention
The invention provides a kind of three phases un identical protection device that can start breaker fail protection, overcome above-mentioned existing
There is the deficiency of technology, it can effectively solve existing three phases un identical protection device and send the action of breaker three phases un identical protection
Afterwards, the problem of can not starting breaker fail protection be present.
The technical scheme is that realized by following measures：A kind of three-phase that can start breaker fail protection
Non-uniform protection device, including defencive function realize that loop, protection act outlet loop, positive pole control bus and negative pole control are female
Line, the defencive function realize that loop and protection act outlet loop are electrically connected with positive pole control bus and negative pole control bus
Between, the defencive function realizes that loop includes the normally opened auxiliary of split-phase circuit breaker position combined loop, negative sequence current relay and touched
Point and time-delay relay coil, positive pole control bus electrically connect with split-phase circuit breaker position combined loop, split-phase circuit breaker position
Together with the normally opened auxiliary contact of combined loop, negative sequence current relay are sequentially connected in series with time-delay relay coil, time-delay relay
Coil electrically connects with negative pole control bus, and the protection act outlet loop includes the normally opened auxiliary contact of time-delay relay and outlet
Actuating relay, positive pole control bus electrically connect with the normally opened auxiliary contact of time-delay relay, the normally opened auxiliary contact of time-delay relay
With outlet actuating relay coil electrically connect, outlet actuating relay coil electrically connected with negative pole control bus, outlet act after
The first normally opened auxiliary contact of electrical equipment electrically connect with the breaker open operation starting relay coil in breaker operation cabinet, outlet action
The second normally opened auxiliary contact of relay and the breaker fail protection starting relay coil electricity in circuit-breaker failure portection equipment
Connection.
Here is the further optimization and/or improvements to foregoing invention technical scheme：
Above-mentioned split-phase circuit breaker position combined loop may include the combined floodgate normally opened contact group sequentially connected and separating brake normally-closed contact group,
Positive pole control bus electrically connects with the input of combined floodgate normally opened contact group, the output end of separating brake normally-closed contact group and negative-sequence current after
The normally opened auxiliary contact electrical connection of electrical equipment, combined floodgate normally opened contact group are normally opened auxiliary by the normally opened auxiliary contact of breaker a phases, breaker b phases
Help contact to be formed in parallel with the normally opened auxiliary contact of breaker c phases, separating brake normally-closed contact group by breaker a phases normally closed auxiliary contact,
Breaker b phases normally closed auxiliary contact and breaker c phase normally closed auxiliary contacts are formed in parallel.
Above-mentioned defencive function realizes that loop may also include function pressing plate, and function pressing plate is connected on positive pole control bus and combined floodgate
Between the input of normally opened contact group, the protection act outlet loop also includes output clamping, and output clamping is connected on positive pole
Between control bus and the normally opened auxiliary contact of time-delay relay.
Reasonable and compact in structure of the present invention, it is easy to use, in the power plant and the power network that solve 220kV and above
It is difficult to start breaker fail protection function problem using the three phases un identical protection of split-phase breaker, works as three phases un identical protection
Action sends but during breaker tripping, can start circuit-breaker failure portection equipment, institute on operation bus where the tripping breaker
There is interval, ensure the reliable elimination of failure.
Brief description of the drawings
Accompanying drawing 1 is the schematic diagram of circuit connection structure of preferred embodiment.
Coding in accompanying drawing is respectively：+ KM is positive pole control bus, and-KM is negative pole control bus, LJ be negative-sequence current after
Electric apparatus coil, LJ1 are the normally opened auxiliary contact of negative sequence current relay, and TJ is time-delay relay coil, and TJ1 is that time-delay relay is normal
Auxiliary contact are driven, TF is outlet actuating relay coil, and TF1 is outlet the first normally opened auxiliary contact of actuating relay, and TF2 is
Mouth the second normally opened auxiliary contact of actuating relay, 52A/a are the normally opened auxiliary contact of breaker a phases, and 52A/b is that breaker b phases are normal
Auxiliary contact are driven, 52A/c is the normally opened auxiliary contact of breaker c phases, and 52B/a is breaker a phase normally closed auxiliary contacts, and 52B/b is
Breaker b phase normally closed auxiliary contacts, 52B/c are breaker c phase normally closed auxiliary contacts, and SB1 is function pressing plate, and SB2 presses for outlet
Plate, TQ are breaker open operation starting relay coil, and TG is breaker fail protection starting relay coil, and 1 is split-phase open circuit
Device position grouping loop, 2 be breaker operation cabinet, and 3 be circuit-breaker failure portection equipment.
Embodiment
The present invention is not limited by following embodiments, can technique according to the invention scheme and actual conditions it is specific to determine
Embodiment.
With reference to embodiment and accompanying drawing, the invention will be further described：
As shown in Figure 1, this can start the three phases un identical protection device of breaker fail protection, including defencive function is realized back
Road, protection act outlet loop, positive pole control bus+KM and negative pole control bus-KM, the defencive function realize loop and guarantor
Shield action outlet loop is electrically connected between positive pole control bus+KM and negative pole control bus-KM, and the defencive function is realized
Loop includes split-phase circuit breaker position combined loop 1, the normally opened auxiliary contact LJ1 of negative sequence current relay and time-delay relay coil
TJ, positive pole control bus+KM electrically connect with split-phase circuit breaker position combined loop 1, split-phase circuit breaker position combined loop 1, bear
Together with the normally opened auxiliary contact LJ1 of sequence electric current relay is sequentially connected in series with time-delay relay coil TJ, time-delay relay coil TJ
Electrically connected with negative pole control bus-KM, the protection act outlet loop includes the normally opened auxiliary contact TJ1 of time-delay relay and gone out
Mouth actuating relay, positive pole control bus+KM electrically connect with the normally opened auxiliary contact TJ1 of time-delay relay, and time-delay relay is normally opened
Auxiliary contact TJ1 electrically connects with outlet actuating relay coil TF, outlet actuating relay coil TF and negative pole control bus-KM
Electrical connection, the outlet normally opened auxiliary contact TF1 of actuating relay first start relay with the breaker open operation in breaker operation cabinet 2
Device coil TQ is electrically connected, the outlet normally opened auxiliary contact TF2 of actuating relay second and the open circuit in circuit-breaker failure portection equipment 3
Device failure protection starting relay coil TG is electrically connected.
In use, A, B, C three-phase current are inputted into negative sequence current relay coil LJ, when unbalanced three-phase lines occur, can produce
Raw negative-sequence current, therefore negative sequence current relay coil obtains electric, the normally opened auxiliary contact LJ1 closures of negative sequence current relay, simultaneously
Split-phase circuit breaker position combined loop 1 is turned on, then time-delay relay coil TJ is obtained electric, the normally opened auxiliary contact TJ1 of time-delay relay
Closure, outlet actuating relay coil TF obtain electric, the outlet normally opened auxiliary contact TF1 of actuating relay first, outlet action relay
The normally opened auxiliary contact TF1 of device first closures make the breaker open operation starting relay coil TQ in breaker operation cabinet 2 obtain it is electric from
And drive breaker three-phase to trip, while exporting the normally opened auxiliary contact TF2 closures of actuating relay second protects breaker failure
Breaker fail protection starting relay coil TG in protection unit 3 obtain it is electric so as to start circuit-breaker failure portection equipment 3, afterwards
Circuit-breaker failure portection equipment 3 judges whether there is electric current in breaker, if not having electric current in breaker, then it represents that breaker three-phase
Trip successfully, circuit-breaker failure portection equipment 3 is without breaker fail protection, if there is electric current in breaker, then it represents that open circuit
Device does not trip success, so as to which circuit-breaker failure portection equipment 3 carries out breaker fail protection.
When unbalanced three-phase lines state disappears, negative-sequence current disappears, negative sequence current relay coil LJ dead electricity, negative-sequence current
Relay normally open auxiliary contact LJ1 disconnects, while split-phase circuit breaker position combined loop 1 disconnects, then time-delay relay coil TJ
Dead electricity, the normally opened auxiliary contact TJ1 of time-delay relay disconnect, and export actuating relay coil TF dead electricity, outlet actuating relay the
One normally opened auxiliary contact TF1 and the outlet normally opened auxiliary contact TF2 of actuating relay second disconnect, so as to stop sending breaker
Trip operation and startup breaker fail protection action.
The present invention solve 220kV and above power plant and power network in differed using the three-phase of split-phase breaker
Cause protection to be difficult to start breaker fail protection function problem, sent when three phases un identical protection acts, but during breaker tripping,
Circuit-breaker failure portection equipment can be started, all intervals on operation bus where the tripping breaker, ensure that the reliable of failure disappears
Remove.
The above-mentioned three phases un identical protection device that can start breaker fail protection can be made further according to being actually needed
Optimization or/and improvement：
As shown in Figure 1, the split-phase circuit breaker position combined loop 1 includes combined floodgate normally opened contact group and the separating brake sequentially connected
Normally-closed contact group, positive pole control bus+KM electrically connect with the input of combined floodgate normally opened contact group, the output of separating brake normally-closed contact group
End electrically connects with the normally opened auxiliary contact LJ1 of negative sequence current relay, and combined floodgate normally opened contact group is by the normally opened auxiliary contact of breaker a phases
The normally opened auxiliary contact 52A/b of 52A/a, breaker b phases is formed in parallel with the normally opened auxiliary contact 52A/c of breaker c phases, and separating brake is normally closed
Contact sets are normally closed by breaker a phase normally closed auxiliary contacts 52B/a, breaker b phase normally closed auxiliary contact 52B/b and breaker c phases
Auxiliary contact 52B/c is formed in parallel.
When unbalanced three-phase lines occur, combined floodgate normally opened contact group closes, and turns on split-phase circuit breaker position combined loop 1, when
Combined floodgate normally opened contact group disconnects when unbalanced three-phase lines disappear, and disconnects split-phase circuit breaker position combined loop 1.
As shown in Figure 1, the defencive function realizes that loop also includes function pressing plate SB1, and function pressing plate SB1 is connected on just
Between pole control bus+KM and the input of combined floodgate normally opened contact group, the protection act outlet loop also includes output clamping
SB2, output clamping SB2 are connected between positive pole control bus+KM and the normally opened auxiliary contact TJ1 of time-delay relay.
Here function pressing plate SB1 and output clamping SB2 is the existing common knowledge of power domain, can control protection work(
The break-make of loop and protection act outlet loop can be realized.When unbalanced three-phase lines occur, function pressing plate SB1 and outlet can be put into
Pressing plate SB2 depresses pressing plate, so as to which connective protection function realizes loop and protection act outlet loop；When unbalanced three-phase lines disappear
When not reset function pressing plate SB1 and output clamping SB2.Here function pressing plate SB1 and output clamping SB2 is added to be mainly used in meeting
Power plant and the needs of power network actual motion, while can individually turn on some loop when device is verified and repaired and be verified, so as to
Conveniently meet the needs of actual verification operation, convenient verification.
Above technical characteristic constitutes highly preferred embodiment of the present invention, and there is stronger adaptability and optimal implementation to imitate for it
Fruit, can be according to the non-essential technical characteristic of increase and decrease be actually needed, to meet the needs of different situations.
Claims (3)
1. a kind of three phases un identical protection device that can start breaker fail protection, it is characterised in that realized including defencive function
Loop, protection act outlet loop, positive pole control bus and negative pole control bus, the defencive function realize that loop and protection are dynamic
Loop is electrically connected between positive pole control bus and negative pole control bus for export, and the defencive function realizes that loop includes dividing
Phase circuit breaker position combined loop, the normally opened auxiliary contact of negative sequence current relay and time-delay relay coil, positive pole control bus
Electrically connected with split-phase circuit breaker position combined loop, split-phase circuit breaker position combined loop, the normally opened auxiliary of negative sequence current relay
Together with contact is sequentially connected in series with time-delay relay coil, time-delay relay coil electrically connects with negative pole control bus, the guarantor
Shield action outlet loop include the normally opened auxiliary contact of time-delay relay and outlet actuating relay, positive pole control bus with delay after
The normally opened auxiliary contact electrical connection of electrical equipment, the normally opened auxiliary contact of time-delay relay are electrically connected with outlet actuating relay coil, exported
Actuating relay coil electrically connects with negative pole control bus, exports the first normally opened auxiliary contact of actuating relay and breaker operator
Breaker open operation starting relay coil electrical connection in case, outlet the second normally opened auxiliary contact of actuating relay lose with breaker
Breaker fail protection starting relay coil electrical connection in clever protection device.
2. the three phases un identical protection device according to claim 1 that breaker fail protection can be started, it is characterised in that
The split-phase circuit breaker position combined loop includes the combined floodgate normally opened contact group and separating brake normally-closed contact group sequentially connected, positive pole control
Bus processed electrically connects with the input of combined floodgate normally opened contact group, and the output end and negative sequence current relay of separating brake normally-closed contact group are normal
Auxiliary contact electrical connection is opened, combined floodgate normally opened contact group is by the normally opened auxiliary contact of breaker a phases, the normally opened auxiliary contact of breaker b phases
It is formed in parallel with the normally opened auxiliary contact of breaker c phases, separating brake normally-closed contact group is by breaker a phases normally closed auxiliary contact, breaker b
Phase normally closed auxiliary contact and breaker c phase normally closed auxiliary contacts are formed in parallel.
3. the three phases un identical protection device according to claim 2 that breaker fail protection can be started, it is characterised in that
The defencive function realizes that loop also includes function pressing plate, and function pressing plate is connected on positive pole control bus and combined floodgate normally opened contact group
Input between, the protection act outlet loop also includes output clamping, output clamping be connected on positive pole control bus and
Between the normally opened auxiliary contact of time-delay relay.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711176183.2A CN107819325A (en) | 2017-11-22 | 2017-11-22 | The three phases un identical protection device of breaker fail protection can be started |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711176183.2A CN107819325A (en) | 2017-11-22 | 2017-11-22 | The three phases un identical protection device of breaker fail protection can be started |
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| Publication Number | Publication Date |
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| CN107819325A true CN107819325A (en) | 2018-03-20 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711176183.2A Pending CN107819325A (en) | 2017-11-22 | 2017-11-22 | The three phases un identical protection device of breaker fail protection can be started |
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| CN (1) | CN107819325A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112260215A (en) * | 2020-11-09 | 2021-01-22 | 山西垣曲抽水蓄能有限公司 | Low-frequency-preventing brake-separating loop of outlet circuit breaker of pumped storage generator set |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112260215A (en) * | 2020-11-09 | 2021-01-22 | 山西垣曲抽水蓄能有限公司 | Low-frequency-preventing brake-separating loop of outlet circuit breaker of pumped storage generator set |
| CN112260215B (en) * | 2020-11-09 | 2022-05-17 | 山西垣曲抽水蓄能有限公司 | Low-frequency-preventing brake-separating loop of outlet circuit breaker of pumped storage generator set |
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