CN110261714B - Short-circuit fault rapid detection method applied to current limiter - Google Patents

Short-circuit fault rapid detection method applied to current limiter Download PDF

Info

Publication number
CN110261714B
CN110261714B CN201910519662.2A CN201910519662A CN110261714B CN 110261714 B CN110261714 B CN 110261714B CN 201910519662 A CN201910519662 A CN 201910519662A CN 110261714 B CN110261714 B CN 110261714B
Authority
CN
China
Prior art keywords
fault
short
fault detection
current
circuit
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
Application number
CN201910519662.2A
Other languages
Chinese (zh)
Other versions
CN110261714A (en
Inventor
陈红坤
李奕璋
陈磊
胡晶
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Wuhan University WHU
Original Assignee
Wuhan University WHU
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Wuhan University WHU filed Critical Wuhan University WHU
Priority to CN201910519662.2A priority Critical patent/CN110261714B/en
Publication of CN110261714A publication Critical patent/CN110261714A/en
Application granted granted Critical
Publication of CN110261714B publication Critical patent/CN110261714B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Emergency Protection Circuit Devices (AREA)
  • Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)

Abstract

The invention provides a short-circuit fault rapid detection method applied to a current limiter. The method calculates the square sum of the three-phase currents of the power transmission line on the side of the current limiter; calculating fault detection quantity; comparing the fault detection threshold with the fault detection quantity, if the fault detection quantity is greater than the fault detection threshold, judging the fault is a short-circuit fault, and outputting a short-circuit fault signal; and if the fault detection quantity is not greater than the fault detection threshold value, not outputting a fault signal. The method can quickly and accurately reflect the transient signal change characteristics of the short-circuit fault of the power system, quickly and reliably identify the short-circuit fault, and further provide more effective guarantee for the circuit breaker to quickly and stably break and break the circuit.

Description

Short-circuit fault rapid detection method applied to current limiter
Technical Field
The invention relates to the technical field of power system fault detection, in particular to a short-circuit fault rapid detection method applied to a current limiter.
Background
With the continuous development and growth of power systems, the system capacity scale and the voltage level are continuously improved, and especially in a high-voltage power grid, the exceeding of the short-circuit current becomes an important problem which threatens the stable operation of the system and influences the quality of electric energy. At present, the problem of exceeding the short-circuit current is solved by adopting a measure of accessing a fault current limiter. After a short-circuit fault occurs, in order to quickly limit short-circuit current and inhibit damage caused by over-standard short-circuit current, a fault current limiter is required to be put into operation in a very short time, so that the research on a quick and accurate short-circuit fault detection method is a necessary condition for the quick and reliable operation of the fault current limiter.
The fault detection technology is very important for the operation effect of the current limiter, and due to the particularity of the current limiter, the short-circuit fault detection method applied to the current limiter has higher requirement on rapidity, and the fault needs to be rapidly identified at the moment of occurrence of the short-circuit fault, so that the current limiter is put into operation. Most of the existing fault detection methods need 3 milliseconds or more, and system protection can send out misjudgment signals under certain non-fault working conditions such as magnetizing inrush current, reactive compensation and the like. Although many fault detection methods exist, most of the detection methods cannot quickly, reliably and accurately identify a short-circuit fault signal, and the method becomes a problem to be solved in the prior art.
Disclosure of Invention
The invention aims to provide a short-circuit fault rapid detection method applied to a current limiter, which is used for solving the impact of short-circuit current on a power system and equipment when a short-circuit fault occurs in an ultrahigh-voltage power grid, limiting the short-circuit current within an allowable range, solving the technical difficulties in the networking and ring forming processes of the power grid and improving the transient stability of the power system and is the key for rapidly and reliably putting the current limiter of the high-voltage power grid into operation.
In order to achieve the purpose, the invention adopts the following technical scheme:
a short-circuit fault rapid detection method applied to a current limiter comprises the following steps:
step 1: calculating the square sum of three-phase currents of the power transmission line on the side of the current limiter;
step 2: calculating fault detection quantity;
and step 3: comparing the fault detection threshold with the fault detection quantity, if the fault detection quantity is greater than the fault detection threshold, judging the fault is a short-circuit fault, and outputting a short-circuit fault signal; and if the fault detection quantity is not greater than the fault detection threshold value, not outputting a fault signal.
Preferably, the sum of the squares of the three-phase current signals is calculated in step 1 as follows:
when the system is in normal operation:
Figure BDA0002096265310000021
Figure BDA0002096265310000022
Figure BDA0002096265310000023
wherein:
ImA＝ImB＝ImC＝Im
Figure BDA0002096265310000024
Figure BDA0002096265310000025
the following can be obtained:
Figure BDA0002096265310000026
when short-circuit fault occurs:
Figure BDA0002096265310000027
if single-phase short-circuit fault occurs:
Figure BDA0002096265310000028
if two-phase short circuit fault occurs:
Figure BDA0002096265310000029
if a three-phase short circuit fault occurs:
Figure BDA00020962653100000210
wherein i (t) is short-circuit fault current, SSC is three-phase current square sum, iAFor phase A current, iBFor phase B current, iCFor phase C current, ImFor steady-state current amplitude, ImIs the amplitude of the AC component, I0To attenuate the magnitude of the dc component, theta is the phase angle,
Figure BDA00020962653100000211
tau is a direct current component decay time constant for a fault initial phase;
preferably, the step 2 of calculating the fault detection quantity FDC (t)n) Comprises the following steps:
Figure BDA00020962653100000212
Figure BDA0002096265310000031
processing signals by adopting a mode of moving a data window, wherein the length of the data window is Ts10ms, current time tnEach time the data window moves by a length delta t-tn-tn-1＝1ms，SC(tn) For intermediate quantities at the present moment, SC (t)n-1) Is tn-1Intermediate amount of time, FDC (t)n) And the fault detection quantity at the current moment is obtained.
Preferably, the comparing the fault detection threshold value with the fault detection amount in step 3 specifically includes:
the short-circuit fault detection logic judgment conditions are as follows:
FDC(tn)＞TH
wherein, FDC (t)n) Represents tnThe time of fault detection, TH represents the threshold of fault detection, FDC (t) at short circuit faultn) The fault detection device can rapidly rise, when the fault detection quantity is larger than the fault detection threshold, the fault is judged to be a short-circuit fault, a short-circuit fault signal is output to the current limiter, the current limiter body is rapidly switched on and switched off, the current limiter is put into operation, and when the fault detection quantity is not larger than the fault detection threshold, the fault is judged not to be short-circuit fault and the fault signal is not output.
The invention has the beneficial effects that:
according to the short-circuit fault rapid detection method applied to the current limiter, the ratio of the square sum mean value of the three-phase current of the forward and backward moving data window is used as the fault detection quantity, the transient signal change characteristic of the short-circuit fault of the high-voltage power grid can be rapidly and accurately reflected, the short-circuit fault can be rapidly and reliably identified, and further more effective guarantee is provided for rapid and stable investment of the current limiter.
Drawings
In order to describe the embodiments of the present invention or the present short-circuit fault detection technical solution in more detail, the drawings required in the description of the embodiments or the present short-circuit fault detection technical solution will be briefly described below. The following drawings illustrate only certain embodiments of the invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments without departing from the inventive concepts herein.
FIG. 1: a flow chart of the short-circuit fault detection method of the invention;
FIG. 2: and detecting the result by using a short-circuit fault detection method.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The following will further describe a short-circuit fault rapid detection method applied to a current limiter according to a specific embodiment of the present invention:
according to the invention, an IEEE-9 node system model is built on a matlab platform, the system comprises an IEEE-9 node, 3 generators, 3 transformers, 6 lines and 3 loads, a Bergeron model is adopted for the lines, the frequency is 50Hz, the rated voltage is 220kV, related parameters are shown in a table 1, a fault point is arranged in the middle of the line 2, four short-circuit fault working conditions are considered, and the fault occurs.
As shown in fig. 1, the method for rapidly detecting a short-circuit fault applied to a current limiter according to the present invention includes the following steps:
step 1: calculating the square sum of three-phase currents of the power transmission line on the side of the current limiter;
the sum of the squares of the three phase current signals is calculated in step 1 as follows:
when the system is in normal operation:
Figure BDA0002096265310000041
Figure BDA0002096265310000042
Figure BDA0002096265310000043
wherein:
ImA＝ImB＝ImC＝Im
Figure BDA0002096265310000044
Figure BDA0002096265310000045
the following can be obtained:
Figure BDA0002096265310000046
when short-circuit fault occurs:
Figure BDA0002096265310000047
if single-phase short-circuit fault occurs:
Figure BDA0002096265310000048
if two-phase short circuit fault occurs:
Figure BDA0002096265310000051
if a three-phase short circuit fault occurs:
Figure BDA0002096265310000052
wherein i (t) is short-circuit fault current, SSC is three-phase current square sum, iAFor phase A current, iBFor phase B current, iCFor phase C current, ImFor steady-state current amplitude, ImIs the amplitude of the AC component, I0To attenuate the magnitude of the dc component, theta is the phase angle,
Figure BDA0002096265310000053
for the fault initial phase, τ is the decay time constant of the dc component.
Step 2: calculating fault detection quantity;
step 2, calculating fault detection quantity FDC (t)n) Comprises the following steps:
Figure BDA0002096265310000054
Figure BDA0002096265310000055
processing signals by adopting a mode of moving a data window, wherein the length of the data window is Ts10ms, current time tnEach time the data window moves by a length delta t-tn-tn-1＝1ms，SC(tn) For intermediate quantities at the present moment, SC (t)n-1) Is tn-1Intermediate amount of time, FDC (t)n) And the fault detection quantity at the current moment is obtained.
And step 3: comparing the fault detection threshold with the fault detection quantity, if the fault detection quantity is greater than the fault detection threshold, judging the fault is a short-circuit fault, and outputting a short-circuit fault signal; and if the fault detection quantity is not greater than the fault detection threshold value, not outputting a fault signal.
Comparing the fault detection threshold value with the fault detection quantity in the step 3 specifically comprises the following steps:
the short-circuit fault detection logic judgment conditions are as follows:
FDC(tn)＞TH
wherein, FDC (t)n) Represents tnThe time of fault detection, TH represents the threshold of fault detection, FDC (t) at short circuit faultn) The fault detection device can rapidly rise, when the fault detection quantity is larger than the fault detection threshold, the fault is judged to be a short-circuit fault, a short-circuit fault signal is output to the current limiter, the current limiter body is rapidly switched on and switched off, the current limiter is put into operation, and when the fault detection quantity is not larger than the fault detection threshold, the fault is judged not to be short-circuit fault and the fault signal is not output.
Considering four short-circuit fault working conditions, after a fault occurs, the detection result of the short-circuit fault detection method is shown in fig. 2. The result of fig. 2 shows that the short-circuit fault rapid detection method applied to the current limiter can rapidly and accurately detect the short-circuit fault and provide powerful guarantee for rapid and reliable operation of the current limiter.
The above examples are only for illustrating the technical solutions of the present invention, and are not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art may make modifications or variations in other forms based on the foregoing embodiments or the accompanying drawings. It is not intended to be exhaustive or to limit all embodiments or aspects of the invention to the precise form disclosed, and all modifications, variations, and equivalents that fall within the spirit and scope of the invention are intended to be embraced therein.

Claims (2)

1. A short-circuit fault rapid detection method applied to a current limiter is characterized by comprising the following steps:
step 1: calculating the square sum of three-phase currents of the power transmission line on the side of the current limiter;
the sum of the squares of the three phase current signals is calculated in step 1 as follows:
when the system is in normal operation:
Figure FDA0002971004090000011
Figure FDA0002971004090000012
Figure FDA0002971004090000013
wherein:
ImA＝ImB＝ImC＝Im
Figure FDA0002971004090000014
Figure FDA0002971004090000015
the following can be obtained:
Figure FDA0002971004090000016
when short-circuit fault occurs:
Figure FDA0002971004090000017
if single-phase short-circuit fault occurs:
Figure FDA0002971004090000018
if two-phase short circuit fault occurs:
Figure FDA0002971004090000019
if a three-phase short circuit fault occurs:
Figure FDA00029710040900000110
wherein i (t) is short-circuit fault current, SSC is three-phase current square sum, iAFor phase A current, iBFor phase B current, iCFor phase C current, ImFor steady-state current amplitude, ImIs the amplitude of the AC component, I0To attenuate the magnitude of the dc component, theta is the phase angle,
Figure FDA0002971004090000021
tau is a direct current component decay time constant for a fault initial phase;
step 2: calculating fault detection quantity;
step 2, the calculated fault detection quantity is as follows:
Figure FDA0002971004090000022
Figure FDA0002971004090000023
processing signals by adopting a mode of moving a data window, wherein the length of the data window is Ts10ms, current time tnEach time the data window moves by a length delta t-tn-tn-1＝1ms，SC(tn) For intermediate quantities at the present moment, SC (t)n-1) Is tn-1Intermediate amount of time, FDC (t)n) Detecting the fault at the current moment;
and step 3: comparing the fault detection threshold with the fault detection quantity, if the fault detection quantity is greater than the fault detection threshold, judging the fault is a short-circuit fault, and outputting a short-circuit fault signal; and if the fault detection quantity is not greater than the fault detection threshold value, not outputting a fault signal.
2. The method for rapidly detecting a short-circuit fault applied to a current limiter according to claim 1, wherein: comparing the fault detection threshold value with the fault detection quantity in the step 3, specifically:
the short-circuit fault detection logic judgment conditions are as follows:
FDC(tn)＞TH
wherein, FDC (t)n) Represents tnThe time of fault detection, TH represents the threshold of fault detection, FDC (t) at short circuit faultn) The fault detection device can rapidly rise, when the fault detection quantity is larger than the fault detection threshold, the fault is judged to be a short-circuit fault, a short-circuit fault signal is output to the current limiter, the current limiter body is rapidly switched on and switched off, the current limiter is put into operation, and when the fault detection quantity is not larger than the fault detection threshold, the fault is judged not to be short-circuit fault and the fault signal is not output.
CN201910519662.2A 2019-06-17 2019-06-17 Short-circuit fault rapid detection method applied to current limiter Active CN110261714B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910519662.2A CN110261714B (en) 2019-06-17 2019-06-17 Short-circuit fault rapid detection method applied to current limiter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910519662.2A CN110261714B (en) 2019-06-17 2019-06-17 Short-circuit fault rapid detection method applied to current limiter

Publications (2)

Publication Number Publication Date
CN110261714A CN110261714A (en) 2019-09-20
CN110261714B true CN110261714B (en) 2021-05-04

Family

ID=67918548

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910519662.2A Active CN110261714B (en) 2019-06-17 2019-06-17 Short-circuit fault rapid detection method applied to current limiter

Country Status (1)

Country Link
CN (1) CN110261714B (en)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110687477B (en) * 2019-10-17 2021-04-02 武汉大学 Rapid short-circuit fault detection system and method applied to high-voltage substation
CN112147536B (en) * 2020-09-07 2022-07-05 广东电网有限责任公司广州供电局 Current-amount-based short-circuit fault rapid detection method
CN112345883A (en) * 2020-10-23 2021-02-09 刘振盛 Transmission line hidden danger early warning system based on traveling wave current
CN113253048B (en) * 2021-04-27 2022-10-28 南京南瑞继保电气有限公司 Short-circuit fault detection method and device
CN113109671B (en) * 2021-04-30 2022-07-19 武汉大学 Method for accelerating detection of small half-wave stage of fault current
CN115588972B (en) * 2022-12-08 2023-05-16 中国南方电网有限责任公司超高压输电公司广州局 Short circuit current limiting control system
CN116755011B (en) * 2023-05-24 2024-08-23 闪渡新能源科技（上海）有限公司 Double-current sensor fault diagnosis method applied to three-phase alternating current motor controller

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4918390A (en) * 1989-04-13 1990-04-17 Pinhas Ziv Method and system for monitoring the condition of a plurality of electrical devices
CN101413982B (en) * 2007-10-18 2011-07-20 深圳长城开发科技股份有限公司 Method and apparatus for detecting short circuit of current loop
CN103683202A (en) * 2012-09-20 2014-03-26 博世力士乐(西安)电子传动与控制有限公司 Device and method for detecting output earth short circuit condition of frequency converter
CN203337763U (en) * 2013-06-21 2013-12-11 国家电网公司 Short-circuit failure judgment device applied to fault current limiter
JP2015192582A (en) * 2014-03-28 2015-11-02 トヨタ自動車株式会社 Current-sensor failure detection apparatus
CN104881709A (en) * 2015-05-12 2015-09-02 国家电网公司 Comprehensive configuration algorithm for optimizing short-circuit current-limiting reactance in electric system
CN106291236A (en) * 2016-07-29 2017-01-04 国家电网公司 Current limiter fault detection method based on transient fault row ripple
CN107561400B (en) * 2017-08-30 2020-05-26 国家电网公司 Distribution network short-circuit fault rapid detection method based on real-time wavelet transform

Also Published As

Publication number Publication date
CN110261714A (en) 2019-09-20

Similar Documents

Publication Publication Date Title
CN110261714B (en) Short-circuit fault rapid detection method applied to current limiter
CN109444644B (en) Transient component differential-based power distribution network single-phase earth fault line selection method
Radojevic et al. New digital algorithm for adaptive reclosing based on the calculation of the faulted phase voltage total harmonic distortion factor
CN107390010B (en) Method for rapidly detecting trailing current of current transformer
CN110601151B (en) Distribution line single-phase earth fault protection method and device based on transient zero sequence differential
CN109617026B (en) Ultrahigh-speed protection method for earth fault of direct-current power grid converter station
CN107561408B (en) Method for improving accuracy rate of small current ground fault line selection
CN109217270B (en) DC line sectional type timing limit overcurrent protection method and device
CN109444659B (en) Annular direct-current power distribution network fault detection method based on voltage prediction
CN109001592A (en) A kind of resonant earthed system fault line selection method for single-phase-to-ground fault based on transient
CN105699842A (en) Direct current near zone alternating current line phase-to-phase fault criterion used by stable control device
CN111257698A (en) Low-current grounding power grid continuous line selection system based on impedance change detection
CN114563659A (en) Injection signal-based three-phase short-circuit fault property identification method
Liu et al. Protection of microgrids with high amounts of renewables: Challenges and solutions
Fletcher et al. Analysis of the effectiveness of non-unit protection methods within DC microgrids
Patil et al. Real time protection technique for DC microgrid using local measurements
CN106026055B (en) The dotted network failure feature of the DER containing inverse type and low pressure incoming relay-protection method
CN113972634B (en) Micro-grid differential protection method for self-adaptive zero-sequence energy injection
CN110794340A (en) Disconnection protection method and circuit for high-voltage overhead line
Kang et al. Busbar differential protection in conjunction with a current transformer compensating algorithm
Xue et al. Fault location principle and 2‐step isolation scheme for a loop‐type DC grid
CN111257699A (en) Low-current grounding power grid line selection system based on impedance detection
CN115113001B (en) Self-adaptive power distribution network single-phase disconnection fault positioning method
CN110596510A (en) Single-phase grounding detection method based on negative sequence current vector analysis
CN112147536B (en) Current-amount-based short-circuit fault rapid detection method

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant