CN102005738A - Method for identifying healthy phase saturation based on current amplitude ratio and differential current harmonic wave - Google Patents
Method for identifying healthy phase saturation based on current amplitude ratio and differential current harmonic wave Download PDFInfo
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- CN102005738A CN102005738A CN2010105887460A CN201010588746A CN102005738A CN 102005738 A CN102005738 A CN 102005738A CN 2010105887460 A CN2010105887460 A CN 2010105887460A CN 201010588746 A CN201010588746 A CN 201010588746A CN 102005738 A CN102005738 A CN 102005738A
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Abstract
The invention provides a method for identifying healthy phase saturation based on current amplitude ratio and differential current harmonic wave. A healthy phase is braked by utilizing fault phase brake current, healthy phase differential protection is locked in healthy phase saturation, and the differential protection is opened when the differential current harmonic wave is smaller according to the characteristics of the differential current harmonic wave so as to ensure that the differential protection can release the outlet in double-phase earthfault and regional high-resistance fault. By using the method, differential misoperation in healthy phase saturation can be well prevented, and error-lock can not occur in transformational fault, developmental fault and other situations.
Description
Technical field
The present invention relates to the mutually saturated method of discrimination of the non-fault of a kind of electric power system.
Background technology
In some regional on-the-spot actual moving process, after outside the system busbar district single-phase fault taking place, the mutation current of passing through property appears in non-fault phase secondary circuit in the recent period, and misoperation has appearred in non-fault phase current differential protection.Its principal character is: distinguish outer single-phase fault, the peaked wave electric current of several cycles appears in non-fault mutually.The saturated criterion of the anti-CT of domestic protection equipment for busbar mainly is to utilize secondary current correctly on the progress of disease basis; be that CT can not enter saturated at once after the fault; one section linear work district is arranged; referring to Cheng Lijun etc. " based on the research of the CT saturation detection scheme of sampled value ". relay, 2000.28 (8): 19-21.Because non-fault phase fault starting and current differential protection move simultaneously, asynchronous method (time difference method) is judged to troubles inside the sample space, does not have Blocking Differential Protection, and non-fault is sent out trip signal mutually, has enlarged the accident scope.
These two kinds of phenomenons all are the behaviors of non-fault phase differential protection generation malfunction in the differential current protection.Get rid of line mutual-inductance in the testing crew investigation process at the scene item by item; increasing-aid current; the influence of factors such as protective device and secondary circuit defective; analyze the wiring of protection and secondary circuit; check the action behavior of protective device; set about from resolving the on-the-spot failure wave-recording information of extracting; according to on-the-spot operating current and voltage waveform; when bus or circuit generation single-phase fault; fault phase short circuit current is not very big; about the 5-6 during for rated current times; but DC component aperiodic with very big decay; the Current Transformer Secondary side of fault phase does not take place saturated; but be the meet burr mutation current of peaked wave that 2-3 cycle occur of non-fault, the direction of mutation current and the fault direction of short circuit current mutually are anti-phase substantially, and non-fault phase current produces distortion; non-fault phase differential current satisfies the ratio brake criterion; referring to Yuan Yubo, 5 snowy peaks, Deng Jieqing etc. " the current transformer three-phase current is gone here and there mutually to the influence of differential protection ". Automation of Electric Systems; 2010,34 (21): 65-68.The visible processing scheme to the problems referred to above of document is generally the saturation characteristic of current transformer is carried out verification at present; Whether the wiring of paying close attention to the secondary circuit neutral point has the phenomenon of loose contact or insulation damages; Carry out type selecting in strict accordance with the protective current transformer, technical conditions; processing method at secondary circuit such as to change to ineligible current transformer; referring to Yuan Yubo; 5 snowy peaks; Deng Jie is clear etc. and " the current transformer three-phase current is gone here and there mutually to the influence of differential protection ". Automation of Electric Systems; 2010,34 (21): 65-68.
Summary of the invention
Goal of the invention
The objective of the invention is: the fault phase current flows through the CT secondary side neutral line and is coupled with non-fault and causes non-fault mutually saturated during the resolution system fault, and time difference method is judged non-fault by accident the problem that causes non-fault phase differential protection action for troubles inside the sample space mutually.
Technical scheme
In order to solve above technical problem; the present invention proposes based on three-phase current amplitude proportion and difference stream harmonic wave; discern the saturated method of non-fault phase CT; it is characterized in that: utilize fault phase stalling current to brake non-fault phase; the non-fault phase of locking differential protection when non-fault is mutually saturated; simultaneously according to difference stream harmonic characteristic at a difference stream harmonic wave hour open differential protection, differential protection can be opened outlet when guaranteeing in double earthfault, the district high resistive fault.
The operating characteristics of the sudden change amount ratio-differential relay of general current differential protection is:
Wherein
Be sudden change amount difference stream amplitude,
Be prominent residual quantity stalling current amplitude,
Be differential startup threshold, k is the ratio restraint coefficient.
From the above mentioned, when non-fault occurs when saturated mutually, general non-fault sudden change amount mutually difference stream is bigger, and with non-fault sudden change amount mutually stalling current sizableness, so formula (1) and formula (2) are not enough to brake.But fault this moment sudden change amount mutually stalling current is generally bigger; based on these characteristics; the present invention adopts fault sudden change amount mutually stalling current to brake non-fault phase; when sudden change amount difference stream during greater than a certain proportion of maximal phase sudden change amount stalling current; open differential protection; otherwise Blocking Differential Protection, as the formula (3):
Wherein
Be maximal phase sudden change amount stalling current amplitude,
Be non-fault phase saturation mutation amount restraint coefficient.
It is different to consider that fault phase current when non-fault is mutually saturated flows through the pro rate relation of non-fault phase CT secondary circuit; and fault sudden change amount mutually stalling current can be decayed in time; the reliably locking in some cases of sudden change amount braking criterion; therefore the present invention adopts fault phase stable state stalling current to brake non-fault phase; when stable state difference stream during greater than a certain proportion of maximal phase stalling current; open differential protection, otherwise Blocking Differential Protection
Wherein
Be maximal phase stalling current amplitude,
For non-fault differs the stream amplitude,
Be the mutually saturated steady-state quantity restraint coefficient of non-fault.
In the taking into account system generating region during double earthfault; fault phase current difference is bigger; said method may cause the mistake locking; in order to reduce this risk; increase the open differentiation of difference stream harmonic wave; main is just in time opposite according to the time dependent trend of difference stream harmonic content that is troubles inside the sample space and the mutually saturated formation of non-fault; troubles inside the sample space difference stream harmonic content can change gradually in time and diminish; but not the harmonic content of the difference stream of the mutually saturated formation of fault can increase with changing gradually fault time; therefore the present invention adopts and judges that the method that harmonic component in the difference stream accounts for difference stream fundametal compoment ratio addresses the above problem; the harmonic component of being on duty in the stream hour; open differential protection, as the formula (5)
Wherein
Be the humorous wave amplitude of difference stream,
Be difference stream fundamental voltage amplitude.
The logic diagram of above method as shown in drawings.
Beneficial effect
1) brake non-fault phase mutually with fault, made full use of the mutually saturated substantive characteristics of non-fault, principle is simple and reliable, can reliable locking when the mutually saturated time difference method of non-fault is judged by accident.
2) this method does not only influence the responsiveness and the operating characteristics of the prominent difference of normal fault relay, can also well prevent misoperation differential when non-fault is mutually saturated, can not miss locking in situations such as evolved fault, developing faults.
3) utilize difference stream harmonic wave open, differential protection operating characteristics when not influencing evolved fault, when outside the bus district takes place, changeing in troubles inside the sample space, the district high resistive fault, can Blocking Differential Protection.
Description of drawings
Accompanying drawing is the logic diagram of the saturated differentiation of the present invention non-fault phase CT.
Embodiment
Embodiment below in conjunction with a half breaker bus mode of connection describes in further detail the present invention.But the invention is not restricted to given example.
1) AC sampling: the current sampling data that obtains each branch road of bus.
4) calculate bus three-phase sudden change amount difference stream
, sudden change amount stalling current
, stable state difference stream
, the stable state stalling current
5) calculate difference stream total harmonic distortion, computing formula is:
,
Be the root mean square value of difference stream,
DC component for difference stream.
Claims (1)
1. discern the mutually saturated method of non-fault based on the current amplitude ratio with difference stream harmonic wave, it is characterized in that, may further comprise the steps:
1) AC sampling: the current sampling data that obtains each branch road of bus;
4) calculate bus three-phase sudden change amount difference stream
, sudden change amount stalling current
, stable state difference stream
, the stable state stalling current
, wherein,
5) calculate difference stream total harmonic distortion, computing formula is:
,
Be the root mean square value of difference stream,
DC component for difference stream;
6) when system's generation disturbance,, satisfy simultaneously as the non-latching differential protection of time difference method
,
,
, and satisfy
With
One of the time, then open differential relay, otherwise locking differential relay, wherein,
Be sudden change amount difference stream amplitude,
Be prominent residual quantity stalling current amplitude,
Be differential startup threshold, k is the ratio restraint coefficient;
Be maximal phase sudden change amount stalling current amplitude,
Be non-fault phase saturation mutation amount restraint coefficient;
Be maximal phase stalling current amplitude,
For non-fault differs the stream amplitude,
Be the mutually saturated steady-state quantity restraint coefficient of non-fault;
Be the humorous wave amplitude of difference stream,
Be difference stream fundamental voltage amplitude.
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Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
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CN102279338A (en) * | 2011-04-29 | 2011-12-14 | 上海磁浮交通发展有限公司 | Method for monitoring two-phase grounding fault of magnetic levitation stator coil |
CN103529321A (en) * | 2013-10-10 | 2014-01-22 | 长园深瑞继保自动化有限公司 | Current transformer saturation detecting method |
WO2015000227A1 (en) * | 2013-07-04 | 2015-01-08 | Wen Jie | Bus protection method for quick locking in ct asymmetrical wire breakage |
CN105024356A (en) * | 2014-06-19 | 2015-11-04 | 许继电气股份有限公司 | Ratio braking type protection method for bus with voltage class of 35 kV or below |
CN109375131A (en) * | 2018-07-31 | 2019-02-22 | 中国电力科学研究院有限公司 | A kind of saturated velocity of current transformer and saturation depth recognition methods and system |
CN109768526A (en) * | 2019-03-13 | 2019-05-17 | 南京南瑞继保电气有限公司 | A kind of method and apparatus being mutually saturated based on current distribution factor identification non-faulting |
CN110927523A (en) * | 2019-11-29 | 2020-03-27 | 国电南瑞科技股份有限公司 | Fault positioning method for flexible direct-current power distribution network |
CN112782494A (en) * | 2019-11-05 | 2021-05-11 | 南京南瑞继保电气有限公司 | Saturation identification method and device for shunt reactor |
WO2021174631A1 (en) * | 2020-03-02 | 2021-09-10 | 国电南瑞科技股份有限公司 | Power transmission line distance protection current transformer saturation identification method and system |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0026620A1 (en) * | 1979-09-27 | 1981-04-08 | THE GENERAL ELECTRIC COMPANY, p.l.c. | Method and apparatus for identifying faults in electric power transmission systems |
CN1474489A (en) * | 2003-08-08 | 2004-02-11 | 国电南京自动化股份有限公司 | Judging method for heavy saturation of current transformer by time-difference method for relay protection |
CN1635679A (en) * | 2003-12-30 | 2005-07-06 | 许继电气股份有限公司 | Method of current transformer saturation identification and method of current differential protection on saturation thereof |
-
2010
- 2010-12-15 CN CN2010105887460A patent/CN102005738B/en active Active
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0026620A1 (en) * | 1979-09-27 | 1981-04-08 | THE GENERAL ELECTRIC COMPANY, p.l.c. | Method and apparatus for identifying faults in electric power transmission systems |
CN1474489A (en) * | 2003-08-08 | 2004-02-11 | 国电南京自动化股份有限公司 | Judging method for heavy saturation of current transformer by time-difference method for relay protection |
CN1635679A (en) * | 2003-12-30 | 2005-07-06 | 许继电气股份有限公司 | Method of current transformer saturation identification and method of current differential protection on saturation thereof |
Non-Patent Citations (3)
Title |
---|
李岩等: "鉴别TA饱和的改进时差法研究", 《继电器》, vol. 29, no. 11, 30 November 2001 (2001-11-30) * |
沈全荣等: "异步法电流互感器饱和判别新原理及其应用", 《电力***自动化》, vol. 29, no. 16, 25 August 2005 (2005-08-25), pages 84 - 86 * |
程利军等: "基于采样值的CT饱和检测方案的研究", 《继电器》, vol. 28, no. 8, 31 August 2000 (2000-08-31), pages 19 - 21 * |
Cited By (15)
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CN102279338B (en) * | 2011-04-29 | 2013-09-25 | 上海磁浮交通发展有限公司 | Method for monitoring two-phase grounding fault of magnetic levitation stator coil |
CN102279338A (en) * | 2011-04-29 | 2011-12-14 | 上海磁浮交通发展有限公司 | Method for monitoring two-phase grounding fault of magnetic levitation stator coil |
WO2015000227A1 (en) * | 2013-07-04 | 2015-01-08 | Wen Jie | Bus protection method for quick locking in ct asymmetrical wire breakage |
CN103529321B (en) * | 2013-10-10 | 2016-01-20 | 长园深瑞继保自动化有限公司 | CT saturation detection method |
CN103529321A (en) * | 2013-10-10 | 2014-01-22 | 长园深瑞继保自动化有限公司 | Current transformer saturation detecting method |
CN105024356B (en) * | 2014-06-19 | 2018-05-29 | 许继电气股份有限公司 | A kind of 35kV and following voltage class ratiometric dynamic formula bus bar protecting method |
CN105024356A (en) * | 2014-06-19 | 2015-11-04 | 许继电气股份有限公司 | Ratio braking type protection method for bus with voltage class of 35 kV or below |
CN109375131A (en) * | 2018-07-31 | 2019-02-22 | 中国电力科学研究院有限公司 | A kind of saturated velocity of current transformer and saturation depth recognition methods and system |
CN109375131B (en) * | 2018-07-31 | 2022-03-04 | 中国电力科学研究院有限公司 | Method and system for identifying saturation speed and saturation depth of current transformer |
CN109768526A (en) * | 2019-03-13 | 2019-05-17 | 南京南瑞继保电气有限公司 | A kind of method and apparatus being mutually saturated based on current distribution factor identification non-faulting |
CN109768526B (en) * | 2019-03-13 | 2020-09-04 | 南京南瑞继保电气有限公司 | Method and device for identifying non-fault phase saturation based on current distribution coefficient |
CN112782494A (en) * | 2019-11-05 | 2021-05-11 | 南京南瑞继保电气有限公司 | Saturation identification method and device for shunt reactor |
CN112782494B (en) * | 2019-11-05 | 2023-10-17 | 南京南瑞继保电气有限公司 | Saturation identification method and device for shunt reactor |
CN110927523A (en) * | 2019-11-29 | 2020-03-27 | 国电南瑞科技股份有限公司 | Fault positioning method for flexible direct-current power distribution network |
WO2021174631A1 (en) * | 2020-03-02 | 2021-09-10 | 国电南瑞科技股份有限公司 | Power transmission line distance protection current transformer saturation identification method and system |
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