CN105244856B - A kind of method for preventing PT broken strings from causing distance protection malfunction - Google Patents
A kind of method for preventing PT broken strings from causing distance protection malfunction Download PDFInfo
- Publication number
- CN105244856B CN105244856B CN201510634461.9A CN201510634461A CN105244856B CN 105244856 B CN105244856 B CN 105244856B CN 201510634461 A CN201510634461 A CN 201510634461A CN 105244856 B CN105244856 B CN 105244856B
- Authority
- CN
- China
- Prior art keywords
- distance protection
- voltage
- floodgate
- preventing
- broken strings
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 230000004224 protection Effects 0.000 title claims abstract description 32
- 230000007257 malfunction Effects 0.000 title claims abstract description 17
- 238000000034 method Methods 0.000 title claims abstract description 13
- 238000005259 measurement Methods 0.000 claims abstract description 6
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000000205 computational method Methods 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000003471 mutagenic agent Substances 0.000 description 1
- 231100000707 mutagenic chemical Toxicity 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
The present invention relates to a kind of method for preventing PT broken strings from causing distance protection malfunction; the front and rear three-phase voltage amplitude of measurement switch combined floodgate; the absolute value of the voltage difference before voltage and combined floodgate after the absolute value of the magnitude of voltage before meeting that any one phase voltage is closed a floodgate in three phase voltages simultaneously is less than threshold value K, the phase voltage is closed a floodgate is again smaller than threshold value K; then judge PT broken strings; wherein, 0.01≤K≤0.1V；If having judged, PT breaks, and implements locking distance protection.The present invention is solved when PT breaks, the problem of causing distance protection malfunction.
Description
Technical field
The present invention relates to a kind of method for preventing PT broken strings from causing distance protection malfunction, belongs to relay protection of power system neck
Domain.
Background technology
When PT breaks, it is the basic demand of distance protection to prevent distance protection malfunction.For the dress of route protection
The PT put breaks when carrying out self-test, and normally only when circuit is run, (switch closes position or has stream) is carried out, when line switching divides position
None- identified goes out PT broken strings, if having occurred and that, PT breaks, then carries out switch combined floodgate, easily causes the risk of distance protection malfunction.
Especially when PT breaks, easily cause standby automatic miscarrying, after extension wire closes a floodgate, cause protection accelerating sections malfunction, so as to lead
Mutagens power station deperssurization emergency.At present, I excessively all there is the possibility of malfunction when closing a floodgate in III section of many producer's distance protections and accelerating sections
Property.Therefore, solve the problems, such as that PT broken strings cause distance protection malfunction necessary.
The content of the invention
It is an object of the invention to overcome the deficiencies in the prior art, it is proposed that one kind prevents PT broken strings from causing distance protection to miss
Dynamic method, solve when PT breaks, the problem of causing distance protection malfunction.
The present invention is achieved by following scheme：
A kind of method for preventing PT broken strings from causing distance protection malfunction, it is characterised in that three before and after measurement switch combined floodgate
Phase voltage amplitude, the absolute value of the magnitude of voltage before meeting that any one phase voltage is closed a floodgate in three phase voltages simultaneously are less than threshold value
K, the absolute value of the voltage difference before voltage and combined floodgate after the phase voltage is closed a floodgate breaks again smaller than threshold value K, then judgement PT, its
In, 0.01≤K≤0.1V；If having judged, PT breaks, and implements locking distance protection.
Further, the method for discrimination of the switch combined floodgate is：Switch is from jump position and is changed into closing position without stream mode or has stream
State, wherein, no stream mode differentiates that threshold value is 0.04 times bis- rated values of CT.
Further, the implementation latch-up protection is distance protection accelerating sections and III of Distance section.
Present invention beneficial effect compared to the prior art is：
Each phase voltage value of three-phase voltage, utilizes the spy of phase voltage value before and after combined floodgate before and after the present invention is closed a floodgate by measurement
Property, the variation characteristic of phase voltage and the characteristic of each phase current before and after combined floodgate determine whether PT lines break, so as to right in time
Device applies corresponding distance protection measure, ensures the normal operation of equipment.Computational methods of the present invention are simple, can find in time
PT whether there is disconnection problem, and realization fast and effectively prevents distance protection malfunction problem caused by PT broken strings.
Embodiment
With reference to embodiment, the present invention will be further described in detail.
A kind of method for preventing malfunction when PT broken strings cause distance protection switch combined floodgate.
The front and rear each phase voltage value of measurement switch combined floodgate, the three-phase voltage amplitude before and after measurement switch closes a floodgate is respectively to close a floodgate
The memory voltage at moment after the memory voltage and combined floodgate at preceding moment, the memory electricity before voltage magnitude can also take three weeks before combined floodgate
Pressure.Wherein, the method for discrimination for switching combined floodgate is：Switch is from jump position and is changed into closing position without stream mode or has stream mode, no stream mode
Differentiate that threshold value is 0.04 times bis- rated values of CT
Because PT is in broken string, the phase voltage value at broken string is 0, the phase voltage measured value only sampling drift of device, zero
Drift value is generally less than 0.01V (two sub-values), and the front and rear magnitude of voltage that closes a floodgate does not change substantially, and according to this principle, PT breaks
The identical criterion of line such as following formula：
And
And
And
Wherein,Closed a floodgate preceding voltage for A phases,Voltage after being closed a floodgate for A phases；Closed a floodgate preceding voltage for B phases,For B
Voltage after mutually closing a floodgate；Closed a floodgate preceding voltage for C phases,Voltage after being closed a floodgate for C phases；K is threshold value (0.01≤K≤0.1V).
If meeting above formula (1), (2), (3) any one, it can be determined that PT breaks.
If having judged, PT breaks, and implements locking distance protection accelerating sections and III of Distance section to it, otherwise implements open distance
Protect accelerating sections and III of Distance section.
As other embodiment, the present invention also can also be according to different actual conditions for the selection without stream threshold value
Using other numerical value.
As other embodiment, when PT breaks, the present invention can also be realized to the other of circuit distance protection
Section.
Above example only states the core concept of the present invention, and every reference the present embodiment is to the present invention in spirit and principle
In the range of any modification and equivalent substitution, obtained effect and the present invention in corresponding technological means, realize the basic phase of purpose
With, obtained technical scheme is still in the scope of protection of the invention.
Claims (3)
- A kind of 1. method for preventing PT broken strings from causing distance protection malfunction, it is characterised in that the front and rear three-phase of measurement switch combined floodgate Voltage magnitude, the absolute value of the magnitude of voltage before meeting that any one phase voltage is closed a floodgate in three phase voltages simultaneously be less than threshold value K, The absolute value of the voltage difference before voltage and combined floodgate after phase voltage combined floodgate breaks again smaller than threshold value K, then judgement PT, its In, 0.01≤K≤0.1V；If having judged, PT breaks, and implements locking distance protection.
- 2. a kind of method for preventing PT broken strings from causing distance protection malfunction according to claim 1, it is characterised in that described Switching the method for discrimination to close a floodgate is：Switch is from jump position and is changed into closing position without stream mode or has stream mode, wherein, no stream mode is sentenced Other threshold value is 0.04 times bis- rated values of CT.
- 3. a kind of method for preventing PT broken strings from causing distance protection malfunction according to claim 1, it is characterised in that described It is distance protection accelerating sections and III of Distance section to implement locking distance protection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510634461.9A CN105244856B (en) | 2015-09-29 | 2015-09-29 | A kind of method for preventing PT broken strings from causing distance protection malfunction |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510634461.9A CN105244856B (en) | 2015-09-29 | 2015-09-29 | A kind of method for preventing PT broken strings from causing distance protection malfunction |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105244856A CN105244856A (en) | 2016-01-13 |
| CN105244856B true CN105244856B (en) | 2018-01-16 |
Family
ID=55042390
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510634461.9A Active CN105244856B (en) | 2015-09-29 | 2015-09-29 | A kind of method for preventing PT broken strings from causing distance protection malfunction |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105244856B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107026423A (en) * | 2017-03-30 | 2017-08-08 | 南京南瑞继保电气有限公司 | One kind prevents PT broken strings from causing overvoltage protection malfunction device and method |
| CN107017604B (en) * | 2017-04-13 | 2019-07-23 | 南京南瑞继保电气有限公司 | A kind of overvoltage protection voltage transformer disconnection faulty action preventing method |
| CN115498774B (en) * | 2022-10-26 | 2023-09-29 | 珠海康晋电气股份有限公司 | Microcomputer type distribution automation station terminal based on multi-line measurement and control |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09219927A (en) * | 1996-02-13 | 1997-08-19 | Toshiba Corp | Pt voltage switch circuit and trip element circuit |
| CN104836330A (en) * | 2015-04-16 | 2015-08-12 | 广东电网有限责任公司揭阳供电局 | Method for quickly detecting bus PT three-phase disconnection of automatic switching device of standby power supply and method for preventing maloperation of bus PT three-phase disconnection of automatic switching device of standby power supply |
| CN104901284A (en) * | 2015-04-16 | 2015-09-09 | 广东电网有限责任公司揭阳供电局 | Detection method and false tripping preventive method of three-phase PT broken line of distance protector |
-
2015
- 2015-09-29 CN CN201510634461.9A patent/CN105244856B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09219927A (en) * | 1996-02-13 | 1997-08-19 | Toshiba Corp | Pt voltage switch circuit and trip element circuit |
| CN104836330A (en) * | 2015-04-16 | 2015-08-12 | 广东电网有限责任公司揭阳供电局 | Method for quickly detecting bus PT three-phase disconnection of automatic switching device of standby power supply and method for preventing maloperation of bus PT three-phase disconnection of automatic switching device of standby power supply |
| CN104901284A (en) * | 2015-04-16 | 2015-09-09 | 广东电网有限责任公司揭阳供电局 | Detection method and false tripping preventive method of three-phase PT broken line of distance protector |
Non-Patent Citations (2)
| Title |
|---|
| PT断线闭锁保护原理与故障原因分析;何庆龙;《应用科技》;20100315;第259-260页 * |
| PT断线闭锁保护误动的分析和管理;周大洲，张高峰;《山东电力技术》;20010201(第2期);第37-38页，47页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN105244856A (en) | 2016-01-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8649131B2 (en) | Method and device for supervising secondary circuit of instrument transformer in power system | |
| Zhalefar et al. | A high-speed adaptive single-phase reclosing technique based on local voltage phasors | |
| EP2628015B1 (en) | Fault direction parameter indicator device using only current and related methods | |
| EP2192416A1 (en) | Method and apparatus for detecting a phase-to-earth fault | |
| CN105244856B (en) | A kind of method for preventing PT broken strings from causing distance protection malfunction | |
| CN105765813B (en) | Electrical shock protection three phase electric leakage breaker | |
| CN106663933A (en) | Transient protection for multi-terminal hvdc grid | |
| CN107315128A (en) | A kind of distributed earthing wire-selecting method and system based on GOOSE | |
| CN107431350B (en) | The traveling-wave protection of power transmission line | |
| CN106655113B (en) | A kind of bus tie dead zone fault identification and fault protecting method | |
| CN103901322A (en) | Small current grounding fault defining method based on power frequency zero sequence voltage and power frequency zero sequence current of defining switch | |
| CN103683228A (en) | Control method of breaker failure protection and automatic reclosing device | |
| CN105870887A (en) | Method for recognizing bus differential area on basis of switching of two current transformers in same bus-tie circuit breaker | |
| Guzmán et al. | Backup transmission line protection for ground faults and power swing detection using synchrophasors | |
| Kandakatla et al. | Advanced vector shift algorithm for islanding detection | |
| Lin et al. | Abnormal operation behavior analysis and countermeasures on the differential protection of converter transformer | |
| CN106410764B (en) | A kind of calculation method and device of positive sequence polarization voltage | |
| CN105738751A (en) | Setting calculation method for bus differential protection current loop line disconnection alarm fixed value | |
| CN104466925A (en) | Micro-grid line protection algorithm based on disturbance voltage | |
| CN104917157B (en) | A kind of earthing pole bus differential protecting is thrown and moves back condition judgement method | |
| Rizvi et al. | Using symmetrical components for internal external fault discrimination in differential protection schemes | |
| CN108155625B (en) | A kind of tranformer protection CT broken string method of discrimination, differential protecting method and device | |
| CN106229950A (en) | A kind of intelligent substation integration protection method | |
| CN106253249B (en) | A kind of method and device of common-tower double-circuit lines pilot protection non-three phase fault opening | |
| CN105071352B (en) | A kind of bus protection device and method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |