CN106981862B - Single-end current sudden change phase selection method - Google Patents

Single-end current sudden change phase selection method Download PDF

Info

Publication number
CN106981862B
CN106981862B CN201610035042.8A CN201610035042A CN106981862B CN 106981862 B CN106981862 B CN 106981862B CN 201610035042 A CN201610035042 A CN 201610035042A CN 106981862 B CN106981862 B CN 106981862B
Authority
CN
China
Prior art keywords
phase
current
sensitivity
relay
criterion
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
CN201610035042.8A
Other languages
Chinese (zh)
Other versions
CN106981862A (en
Inventor
郭雅蓉
柳焕章
周泽昕
王兴国
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.)
State Grid Corp of China SGCC
China Electric Power Research Institute Co Ltd CEPRI
State Grid Ningxia Electric Power Co Ltd
Original Assignee
State Grid Corp of China SGCC
China Electric Power Research Institute Co Ltd CEPRI
State Grid Ningxia Electric Power Co Ltd
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 State Grid Corp of China SGCC, China Electric Power Research Institute Co Ltd CEPRI, State Grid Ningxia Electric Power Co Ltd filed Critical State Grid Corp of China SGCC
Priority to CN201610035042.8A priority Critical patent/CN106981862B/en
Publication of CN106981862A publication Critical patent/CN106981862A/en
Application granted granted Critical
Publication of CN106981862B publication Critical patent/CN106981862B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

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
    • H02H7/267—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 for parallel lines and wires
    • 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
    • G01R31/08—Locating faults in cables, transmission lines, or networks
    • G01R31/081—Locating faults in cables, transmission lines, or networks according to type of conductors
    • G01R31/086—Locating faults in cables, transmission lines, or networks according to type of conductors in power transmission or distribution networks, i.e. with interconnected conductors

Abstract

The invention relates to a single-end current sudden change phase selection method, which comprises the following steps: constructing a criterion of a sudden change current phase selection relay; constructing a high-sensitivity and low-sensitivity variable current phase selection criterion; and selecting a fault phase by matching high-sensitivity and low-sensitivity sudden-change current phase selection criteria. The technical scheme of the invention is based on single-end current abrupt change, adopts different sensitivities to select the fault phase in a matching way, and has the characteristics of high sensitivity and small influence by load components and transition resistance.

Description

Single-end current sudden change phase selection method
Technical Field
The invention relates to the field of relay protection, in particular to a single-ended current sudden change phase selection method.
Background
The zero sequence current protection, distance protection and automatic reclosing elements all need to correctly act through the phase selection element. The phase selection elements which are widely applied in the existing power system are sequence component phase selection and mutation phase selection, and the problem of insufficient sensitivity of the phase selection elements on the weak power source side of the sequence component phase selection is solved; the phase selection of the current phase current difference sudden change is influenced by a non-periodic component, three phase current sudden changes possibly have large deviation and are greatly influenced by load current, and when a single-phase grounding fault occurs under the heavy load condition, the phase selection of the phase selection element fails, and the result is that the slight fault (the single-phase grounding fault occurs through high resistance) protects and jumps three phases.
Disclosure of Invention
In view of the above problems, an object of the present invention is to provide a single-ended current step amount phase selection method, which has the advantages of high sensitivity and small influence by load components and transition resistance.
In order to achieve the purpose, the invention adopts the following technical scheme: a single-ended magnitude current abrupt change phase selection method comprises the following steps:
constructing a criterion of a sudden change current phase selection relay;
constructing a high-sensitivity and low-sensitivity variable current phase selection criterion;
and selecting a fault phase by matching high-sensitivity and low-sensitivity sudden-change current phase selection criteria.
And if the criterion of the sudden change current phase selection relay is that the sudden change of the phase current is larger than k times of the sudden change of the current of the other two phases, the phase is a fault phase.
The criterion of the sudden change current phase selection relay is established by the following formula:
a relay A: delta Ia(t)＞k[ΔIbc(t)-0.15ΔImax(t)]
A relay B: delta Ib(t)＞k[ΔIca(t)-0.15ΔImax(t)]
And a relay C: delta Ic(t)＞k[ΔIab(t)-0.15ΔImax(t)]
Wherein, the maximum value of the phase current abrupt change delta Imax(t)＝MAX{ΔIab，ΔIbc，ΔIca}，ΔImax(t)＞Imaxset；ΔIa(t) is the a-phase current transient, Δ Ibc(t) is the interphase current sudden change of bc two-phase, k is the criterion coefficient, Delta Ib(t) is the amount of the sudden change in the b-phase current,. DELTA.Ica(t) is the amount of inter-phase current sudden change of the two phases ca,. DELTA.Ic(t) is the amount of the c-phase current transient,. DELTA.Iab(t) is the interphase current burst of the ab two phases, ImaxsetAnd the maximum value of the sudden change amount of the phase current is fixed.
When the criterion of only one relay in the three relays meets the inequality condition, the phase corresponding to the left side variable current of the inequality is a fault phase; and when the criteria of the three relays do not meet the inequality condition, judging the relay to be a multi-phase fault.
And constructing a high-sensitivity and low-sensitivity mutation current phase selection criterion by changing the criterion coefficient k.
The high sensitivity criterion is:
a relay A: delta Ia(t)＞kg[ΔIbc(t)-0.15ΔImax(t)]
A relay B: delta Ib(t)＞kg[ΔIca(t)-0.15ΔImax(t)]
And a relay C: delta Ic(t)＞kg[ΔIab(t)-0.15ΔImax(t)]
Wherein, Delta Imax(t)＞Imaxset-g。
The low sensitivity criterion is:
a relay A: delta Ia(t)＞kd[ΔIbc(t)-0.15ΔImax(t)]
A relay B: delta Ib(t)＞kd[ΔIca(t)-0.15ΔImax(t)]
And a relay C: delta Ic(t)＞kd[ΔIab(t)-0.15ΔImax(t)]
Wherein, Delta Imax(t)＞Imaxset-d。
In the high sensitivity criterion: high sensitivity criterion coefficient kg3, high sensitivity criterion phase current sudden change maximum value fixed value Imaxset-g400A; in the low sensitivity criterion: low sensitivity criterion coefficient k d4, low sensitivity criterion phase current abrupt change maximum value fixed value Imaxset-d＝600A。
Judging the relay group to be a multi-phase fault when the high-sensitivity relay group does not act; when only one relay of the low-sensitivity relay group acts, the single-phase fault is judged; otherwise, the phase selection fails.
Compared with the closest prior art, the technical scheme provided by the invention has the following excellent effects
1. The technical scheme of the invention is based on single-end current abrupt change, and adopts different sensitivity to select fault phases;
2. the technical scheme of the invention better ensures that the zero-sequence current protection, the distance protection and the automatic reclosing element correctly act through the phase selection element;
3. the technical scheme of the invention reduces the occurrence of faults;
4. the technical scheme of the invention accurately selects the adaptive phase selection element.
Drawings
FIG. 1 is a schematic diagram of a fault line according to an embodiment of the present invention;
fig. 2 is a schematic structural diagram of sampling values of three-phase currents on two sides of a line MN according to an embodiment of the present invention;
FIG. 3 is a diagram illustrating a result of a low sensitivity criterion at the M side of a line according to an embodiment of the present invention;
FIG. 4 is a diagram illustrating a result of a low sensitivity criterion for the N-side of the line according to an embodiment of the present invention;
fig. 5 is a schematic diagram of sampling values of three-phase currents on two sides of a line MN according to an embodiment of the present invention;
fig. 6 is a schematic diagram of a result of a high sensitivity criterion at the M side of the line according to an embodiment of the present invention;
fig. 7 is a schematic diagram of a result of a high sensitivity criterion of the N side of the line according to the embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to examples.
Example 1:
the invention of the present example provides a single-end current sudden change phase selection method, which comprises the following steps:
(1) and constructing a sudden change current phase selection relay, wherein the criterion is that the phase current sudden change is larger than k (criterion coefficient) times of the current sudden change of the other two phases, and the phase is a fault phase.
A relay A: delta Ia(t)＞k[ΔIbc(t)-0.15ΔImax(t)]
A relay B: delta Ib(t)＞k[ΔIca(t)-0.15ΔImax(t)]
And a relay C: delta Ic(t)＞k[ΔIab(t)-0.15ΔImax(t)]
Wherein: delta Imax(t)＝MAX{ΔIab，ΔIab，ΔIca}，ΔImax(t)＞Imaxset
When only one of the three relays meets the inequality condition, the phase corresponding to the left-side variable current of the inequality is a fault phase; and when none of the three relays does not meet the inequality condition, judging the relay to be a multi-phase fault.
Right side of inequality criterion minus 0.15 delta Imax(t) for preventing Z after failure1≠Z2Causing a phase-to-phase current burst of the non-faulted phase.
(2) And constructing a high-sensitivity and low-sensitivity mutation current phase selection criterion by changing the criterion coefficient k.
In the high sensitivity criterion: k is a radical ofg＝3，Imaxset-g400A; in the low sensitivity criterion: k is a radical ofd＝4，Imaxset-d＝600A。
(3) And selecting the fault phase by matching the high and low sensitivity criteria.
Judging the relay group to be a multi-phase fault when the high-sensitivity relay group does not act; when only one relay of the low-sensitivity relay group acts, the single-phase fault is judged. Other phase decisions fail.
Taking the line MN in fig. 1 as an example, different fault types are simulated, the system voltage level is 1000kV, the line length is 200km, and the protection is installed at 1 and 2.
(1) Three-phase current at acquisition protection 1 and 2
Figure BDA0000910045750000041
And (4) calculating phase current break variables and interphase current break variables.
(2) Separately calculating A, B, C three-phase high sensitivity criterion and low sensitivity criterion.
(3) Judging the relay group to be a multi-phase fault when the high-sensitivity relay group does not act; when only one relay of the low-sensitivity relay group acts, the single-phase fault is judged. Other phase decisions fail.
(4) Simulation verification:
1) the fault type is a B-phase grounding fault through a 500 omega transition resistor, and fig. 2 shows three-phase current sampling values on two sides of a line MN. FIG. 3 shows the result of the low sensitivity criterion at the M side of the line, and FIG. 4 shows the result of the low sensitivity criterion at the N side of the line
The two sides of the line have low-sensitivity criterion actions of only the B phase, the B phase has a fault phase, and the phase selection result is correct.
2) The fault type is a BC phase inter-phase fault through a 25 omega transition resistor, and fig. 5 shows three-phase current sampling values on two sides of a line MN. FIG. 6 shows the result of the line M-side high sensitivity criterion, and FIG. 7 shows the result of the line N-side high sensitivity criterion
The high-sensitivity criteria of the three phases at the two sides of the line are not actuated, the multi-phase fault is detected, and the phase selection result is correct.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting the same, and those skilled in the art should understand that although the above embodiments are referred to: modifications and equivalents may be made to the embodiments of the invention without departing from the spirit and scope of the invention, which is set forth in the claims below.

Claims (3)

1. A single-end current sudden change phase selection method is characterized in that: the method comprises the following steps:
constructing a criterion of a sudden change current phase selection relay;
constructing a high-sensitivity and low-sensitivity variable current phase selection criterion;
selecting a fault phase by matching high-sensitivity and low-sensitivity variable current phase selection criteria;
the criterion of the sudden change current phase selection relay is established by the following formula:
a relay A: delta Ia(t)＞k[ΔIbc(t)-0.15ΔImax(t)]
A relay B: delta Ib(t)＞k[ΔIca(t)-0.15ΔImax(t)]
And a relay C: delta Ic(t)＞k[ΔIab(t)-0.15ΔImax(t)]
Wherein, the maximum value of the phase current abrupt change delta Imax(t)＝MAX{ΔIab，ΔIbc，ΔIca}，ΔImax(t)＞Imaxset；ΔIa(t) is the a-phase current transient, Δ Ibc(t) is the interphase current sudden change of bc two-phase, k is the criterion coefficient, Delta Ib(t) is the amount of the sudden change in the b-phase current,. DELTA.Ica(t) is the amount of inter-phase current sudden change of the two phases ca,. DELTA.Ic(t) is the amount of the c-phase current transient,. DELTA.Iab(t) is the interphase current burst of the ab two phases, ImaxsetSetting the maximum value of the phase current abrupt change quantity;
constructing a high-sensitivity and low-sensitivity mutation current phase selection criterion by changing a criterion coefficient k;
the high sensitivity criterion is:
a relay A: delta Ia(t)＞kg[ΔIbc(t)-0.15ΔImax(t)]
A relay B: delta Ib(t)＞kg[ΔIca(t)-0.15ΔImax(t)]
And a relay C: delta Ic(t)＞kg[ΔIab(t)-0.15ΔImax(t)]
Wherein, when k is kgWhen k isgCoefficient of high sensitivity criterion, and Δ Imax(t)＞Imaxset-g；Imaxset-gDetermining the maximum value of the phase current sudden change for high sensitivity criterion;
in the high sensitivity criterion: the high sensitivity criterion coefficient kg3, and the maximum value I of the phase current sudden change of the high-sensitivity criterion is fixedmaxset-g＝400A；
The low sensitivity criterion is:
a relay A: delta Ia(t)＞kd[ΔIbc(t)-0.15ΔImax(t)]
A relay B: delta Ib(t)＞kd[ΔIca(t)-0.15ΔImax(t)]
And a relay C: delta Ic(t)＞kd[ΔIab(t)-0.15ΔImax(t)]
Wherein, when k is kdWhen k isdCoefficient of low sensitivity criterion, and Δ Imax(t)＞Imaxset-d，Imaxset-dIs lowThe maximum value of the sensitivity phase current abrupt change is fixed;
the low sensitivity criterion coefficient kd4, the maximum value of the sudden change of the low-sensitivity phase is fixed Imaxset-d＝600A；
Judging the relay group to be a multi-phase fault when the high-sensitivity relay group does not act; when only one relay of the low-sensitivity relay group acts, the single-phase fault is judged; otherwise, the phase selection fails.
2. The single-ended current mutation phase selection method according to claim 1, wherein: and if the criterion of the sudden change current phase selection relay is that the sudden change of the phase current is larger than k times of the sudden change of the current of the other two phases, the phase is a fault phase.
3. The single-ended current mutation phase selection method according to claim 1, wherein: when the criterion of only one relay in the three relays meets the inequality condition, the phase corresponding to the left side variable current of the inequality is a fault phase; and when the criteria of the three relays do not meet the inequality condition, judging the relay to be a multi-phase fault.
CN201610035042.8A 2016-01-19 2016-01-19 Single-end current sudden change phase selection method Active CN106981862B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201610035042.8A CN106981862B (en) 2016-01-19 2016-01-19 Single-end current sudden change phase selection method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201610035042.8A CN106981862B (en) 2016-01-19 2016-01-19 Single-end current sudden change phase selection method

Publications (2)

Publication Number Publication Date
CN106981862A CN106981862A (en) 2017-07-25
CN106981862B true CN106981862B (en) 2020-03-06

Family

ID=59340896

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201610035042.8A Active CN106981862B (en) 2016-01-19 2016-01-19 Single-end current sudden change phase selection method

Country Status (1)

Country Link
CN (1) CN106981862B (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109193591B (en) * 2018-10-23 2020-03-31 北京四方继保自动化股份有限公司 Method for judging starting of interphase current break variable through floating threshold
CN113659530B (en) * 2021-09-24 2022-09-23 许昌开普检测研究院股份有限公司 Incoming line open-phase judgment method suitable for Y/D-11 and Y/V traction transformer

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102608495A (en) * 2012-03-02 2012-07-25 华北电力大学 Fault phase selection method based on current break variable

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102608495A (en) * 2012-03-02 2012-07-25 华北电力大学 Fault phase selection method based on current break variable

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
一种电流突变量选相元件的探讨;赵洪峰等;《继电器》;20050701;第33卷(第13期);第6-9页 *

Also Published As

Publication number Publication date
CN106981862A (en) 2017-07-25

Similar Documents

Publication Publication Date Title
US7345488B2 (en) Apparatus and method for determining a faulted phase of a three-phase ungrounded power system
US7599161B2 (en) Relay device and corresponding method
EP2680385B1 (en) Differential protection in electrical power networks
US10333291B2 (en) Multiple generator ground fault detection
Filomena et al. Ground distance relaying with fault-resistance compensation for unbalanced systems
US10859639B2 (en) Fault-type identification in an electric power delivery system using composite signals
US8410785B2 (en) Electrical power system phase and ground protection using an adaptive quadrilateral characteristics
CN101813739B (en) Adaptive three-phase symmetric fault phase selecting method for ultra high voltage transmission line
FI126434B (en) Procedure for earth-fault protection in a three-phase mains
CN106981862B (en) Single-end current sudden change phase selection method
CN111740379B (en) Method for automatically adjusting zero sequence protection two-segment and three-segment time constant values on line
CN110133452B (en) Mixed-voltage same-tower fault phase selection method based on waveform correlation coefficient and current mutation quantity
CN111736107A (en) CT (computed tomography) disconnection detection method, system and medium based on sequence current phase comparison
Halinka et al. New area measuring and decision algorithm concepts for power lines' distance protection
Das et al. A novel method for turn to turn fault detection in shunt reactors
CN110729705B (en) Short-circuit protection method for direct-current transmission converter valve
Wilson et al. Detecting open phase conductors
CN104730417B (en) It is a kind of using negative-sequence current as the transmission line of electricity method of single end distance measurement of amount of polarization
CN108037417B (en) Quick detection method for faults of ungrounded system
CN112578310A (en) Detection method for single-phase grounding line selection tripping function
CN109997287B (en) Method and control system for fault direction detection
Schindler et al. Advanced load blinding of distance protection relays based on physical grid limitations
Htita et al. Multi-function digital relay for power Autotransformer protection
Patel et al. Fault detection & classification using innovative MFCDFT based slope tracking method for digital distance protection
Sharon et al. New directional protection for distribution networks

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