CN111781468B - Asynchronous fault distance measurement method and system for T-shaped high-voltage transmission line - Google Patents
Asynchronous fault distance measurement method and system for T-shaped high-voltage transmission line Download PDFInfo
- Publication number
- CN111781468B CN111781468B CN202010680858.2A CN202010680858A CN111781468B CN 111781468 B CN111781468 B CN 111781468B CN 202010680858 A CN202010680858 A CN 202010680858A CN 111781468 B CN111781468 B CN 111781468B
- Authority
- CN
- China
- Prior art keywords
- fault
- positive sequence
- voltage
- branch
- distance
- 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
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
- G01R31/08—Locating faults in cables, transmission lines, or networks
- G01R31/081—Locating faults in cables, transmission lines, or networks according to type of conductors
- G01R31/085—Locating faults in cables, transmission lines, or networks according to type of conductors in power transmission or distribution lines, e.g. overhead
-
- 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
- G01R31/088—Aspects of digital computing
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
- Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
- Y04S10/00—Systems supporting electrical power generation, transmission or distribution
- Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
- Y04S10/52—Outage or fault management, e.g. fault detection or location
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Mathematical Physics (AREA)
- Theoretical Computer Science (AREA)
- Locating Faults (AREA)
Abstract
The invention relates to a T-shaped high-voltage transmission line asynchronous fault distance measurement method, which comprises the steps of extracting positive sequence voltage and current at three ends and fundamental wave phasor values of the positive sequence fault voltage and current; then, assuming that the fault occurs on each branch, obtaining the distance between the fault and the T node by using a distance measurement equation; then directly distinguishing fault branches and fault distances by using the characteristics of the distances obtained by the branches; and the correctness of the data is verified through an auxiliary criterion. The method utilizes the positive sequence component and the positive sequence fault component to directly measure the distance without judging the fault type, directly integrates fault branch judgment and fault distance measurement into a whole, is simple, does not need iteration, has no pseudo root, and avoids the defect that the traditional asynchronous fault distance measuring method needs to identify the pseudo root. The invention also provides a T-shaped high-voltage transmission line asynchronous fault distance measuring system.
Description
Technical Field
The invention relates to the technical field of power transmission systems, in particular to a T-shaped high-voltage transmission line asynchronous fault distance measurement method and system.
Background
The T-shaped power transmission line has large transmission power and heavy load, and once a fault occurs, it is very important to reliably and accurately find a fault position. The fault location method can be mainly divided into a traveling wave location method and a fault analysis location method in principle. The traveling wave distance measurement method has the defects that the traveling wave has dispersion phenomenon, the distance measurement dead zone exists when the voltage zero-crossing fault occurs, special hardware facilities need to be invested, the technical implementation is complex and the like, and the fault analysis distance measurement method has the advantages of being capable of utilizing the existing equipment, low in investment and the like, so that the method is widely applied.
The fault analysis ranging method can be divided into a synchronous ranging method and an asynchronous ranging method according to whether data at each end is synchronous or not. The synchronous ranging method utilizes a synchronization method to synchronize data of each end, but the asynchronous ranging method has wide application because the data of each end cannot be completely synchronized in consideration of delay errors of equipment, networks and the like. The traditional T-type asynchronous ranging method is used for fault ranging in two steps, firstly, different voltages of T nodes obtained by each end are used for judging a fault branch, secondly, normal branches are combined into a branch, and then the branch and the fault branch are equivalent to a double-end line for double-end asynchronous fault ranging, when a high-resistance fault occurs near the T node, the voltages obtained by each end are approximately the same, the fault of the T node can be judged when errors such as a mutual inductor are considered, and therefore the ranging error is larger.
Disclosure of Invention
In view of the above, it is necessary to provide an asynchronous fault location method for a T-type high-voltage transmission line, which can reliably and accurately find a fault location.
It is also necessary to provide a T-type high-voltage transmission line asynchronous fault location system which can reliably and accurately find the fault location.
A T-shaped high-voltage transmission line asynchronous fault distance measurement method comprises the following steps:
s001, respectively marking three ends of the T-shaped power transmission line as M, N and P, performing data filtering on voltage and current data of measuring points of the three ends M, N and P, extracting fundamental phasor, and solving positive sequence voltage and current and positive sequence fault voltage and current of the measuring points of the three ends by using a symmetric component method;
step S002, substituting the positive sequence voltage and current of the measuring point and the positive sequence fault voltage and current of the measuring point into a formula according to the positive sequence wave impedance and the propagation coefficient of the line by using the line lengths of the MT, NT and PT branches, and respectively solving the positive sequence voltage and the positive sequence fault voltage of the T node and the positive sequence current and the positive sequence fault current injected into the T node;
step S003, one of the three branches is assumed as a fault branch, a fault point on the branch is an imaginary fault point, data of each end is brought into a distance measurement function of the branch, and the distance between the imaginary fault point and a T node is calculated; similarly, respectively assuming the other two branches as the branches with faults, substituting each end data into the ranging function of each branch, and calculating the distance between the other two assumed fault points and the T node;
and step S004, comparing the distances from the three virtual fault points to the T node with the line length of the corresponding branch, if the distance from one virtual fault point to the T node is less than the line length of the branch and more than zero, the fault occurs on the branch, and the virtual fault distance of the branch is calculated to be the distance from the fault to the T node.
Preferably, theThe line lengths of the MT, NT and PT branches are used, and according to the positive sequence wave impedance and propagation coefficient of the line, the positive sequence voltage and current of the measuring point and the positive sequence fault voltage and current are substituted into a formula, and the positive sequence voltage U of the T node is respectively solved iT (i = M, N, P), positive sequence fault voltage Δ U iT And a positive sequence current I injected into the T node iT Positive sequence fault current delta I iT Comprises the following steps:
wherein, U i 、ΔU i Positive sequence voltage and positive sequence fault voltage of terminal I, respectively i 、ΔI i Positive sequence current and positive sequence fault current at terminal i,/ iT The length of the circuit of the iT branch is Z, the positive sequence wave impedance of the circuit is Z, and the positive sequence propagation coefficient of the circuit is gamma.
Preferably, in step S003, assuming that the fault occurs on the MT branch, the ranging function is:
wherein the content of the first and second substances,
B 1 ＝2(U NT I PT -U PT I NT )ΔI PT Z-2(ΔU NT ΔI PT -ΔU PT ΔI NT )I PT Z，
C 1 ＝(ΔU NT ΔI PT -ΔU PT ΔI NT )U PT -(U NT I PT -U PT I NT )ΔU PT ，
A 2 ＝(ΔU PT ΔI NT -ΔU NT ΔI PT )(2U MT I NT +U NT I MT )-(U PT I NT -U NT I PT )(2ΔU MT ΔI NT +ΔU NT ΔI MT )，
B 2 ＝2(U PT I NT -U NT I PT )ΔI NT Z-2(ΔU PT ΔI NT -ΔU NT ΔI PT )I NT Z，
C 2 ＝(ΔU PT ΔI NT -ΔU NT ΔI PT )U NT -(U PT I NT -U NT I PT )ΔU NT 。
preferably, in step S003, assuming that the fault occurs on the NT branch, the ranging function is:
wherein, the first and the second end of the pipe are connected with each other,
B 1 ＝2(U MT I PT -U PT I MT )ΔI PT Z-2(ΔU MT ΔI PT -ΔU PT ΔI MT )I PT Z，
C 1 ＝(ΔU MT ΔI PT -ΔU PT ΔI MT )U PT -(U MT I PT -U PT I MT )ΔU PT ，
A 2 ＝(ΔU PT ΔI MT -ΔU MT ΔI PT )(2U NT I MT +U MT I NT )-(U PT I MT -U MT I PT )(2ΔU NT ΔI MT +ΔU MT ΔI NT )，
B 2 ＝2(U PT I MT -U MT I PT )ΔI MT Z-2(ΔU PT ΔI MT -ΔU MT ΔI PT )I MT Z，
C 2 ＝(ΔU PT ΔI MT -ΔU MT ΔI PT )U MT -(U PT I MT -U MT I PT )ΔU MT 。
preferably, in step S003, assuming that a fault occurs on the PT branch, the ranging function is:
wherein the content of the first and second substances,
B 1 ＝2(U MT I NT -U NT I MT )ΔI NT Z-2(ΔU MT ΔI NT -ΔU NT ΔI MT )I NT Z，
C 1 ＝(ΔU MT ΔI NT -ΔU NT ΔI MT )U NT -(U MT I NT -U NT I MT )ΔU NT ，
A 2 ＝(ΔU NT ΔI MT -ΔU MT ΔI NT )(2U PT I MT +U MT I PT )-(U NT I MT -U MT I NT )(2ΔU PT ΔI MT +ΔU MT ΔI PT )，
B 2 ＝2(U NT I MT -U MT I NT )ΔI MT Z-2(ΔU NT ΔI MT -ΔU MT ΔI NT )I MT Z，
C 2 ＝(ΔU NT ΔI MT -ΔU MT ΔI NT )U MT -(U NT I MT -U MT I NT )ΔU MT 。
preferably, the T-type high-voltage transmission line asynchronous fault distance measurement method further comprises an auxiliary criterion for verifying the correctness of dataSex, i.e. distance of imaginary fault point of non-faulty branch from T node
Distance of fault point from T node of fault branch
Substituting an auxiliary criterion function:
wherein f is a modulo function; if f is<δ, then the distance of the fault point from the T node is valid; if f is>Delta, strengthening filtering the data of the three ends, and recalculating; when the distances from the virtual fault points on the two or three solved branches to the T node are all satisfied
When, if f<Delta, then the actual fault is a T node fault; if f>Delta, the data enhancement filtering of the three ends is recalculated.
A T-shaped high-voltage transmission line asynchronous fault ranging system comprises a data input module, a data extraction module, a ranging function calculation module and a numerical analysis module. The data input module is used for inputting voltage and current data of the measuring points at the three ends of M, N and P into the system; the data extraction module is used for filtering voltage and current data of the measuring points, extracting fundamental phasor, solving a positive sequence component and a positive sequence fault component of three ends by using a symmetric component method, and outputting the positive sequence component and the positive sequence fault component of the three ends to the ranging function calculation module; the distance measurement function calculation module is used for calculating the distance from the virtual fault point on the three branches to the T node; and the numerical analysis module is used for analyzing the distance from the supposed fault point to the T node, verifying the correctness of the data through auxiliary criteria and obtaining a fault branch and a fault distance.
Has the advantages that: the asynchronous fault distance measurement method for the T-shaped high-voltage transmission line integrates fault branch judgment and fault distance measurement, has no distance measurement dead zone, and has no defect of false root in the traditional asynchronous fault distance measurement method; the distance measurement method has no complex iterative program, can obtain the fault distance by using an analytical expression, has auxiliary criteria to judge the correctness of data, and is simple and reliable; the distance measurement method does not need to judge the fault type, is basically not influenced by transition resistance, system impedance, asynchronous angles, fault positions and the like, and has high distance measurement precision.
Drawings
Fig. 1 is a flowchart of the T-type high-voltage transmission line asynchronous fault location method of the present invention.
Fig. 2 is a schematic diagram of a T-type transmission line fault ranging on an NT branch when the fault occurs on the NT branch.
Fig. 3 is a schematic diagram of a T-type transmission line fault ranging on NT branch when a fault occurs on MT branch.
Detailed Description
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following description will be given with reference to the embodiments.
A T-shaped high-voltage transmission line asynchronous fault distance measurement method comprises the following steps:
referring to fig. 1, in step S001, three terminals of the T-type power transmission line are respectively marked as M, N, and P, data filtering is performed on voltage and current data of measurement points at the three terminals M, N, and P, fundamental phasor is extracted, and positive sequence voltage, current, and positive sequence fault voltage, current of the measurement points at the three terminals are solved by using a symmetric component method;
step S002, substituting the positive sequence voltage and current of the measuring point and the positive sequence fault voltage and current into a formula according to the positive sequence wave impedance and the propagation coefficient of the line by using the line lengths of the MT, NT and PT branches, and solving the positive sequence voltage and the positive sequence fault voltage from each end to the T node and the positive sequence current and the positive sequence fault current injected into the T node;
step S003, one of the three branches is assumed as a fault branch, a fault point on the branch is an imaginary fault point, data of each end is brought into a distance measurement function of the branch, and the distance between the imaginary fault point and a T node is calculated; in the same way, the other two branches are respectively assumed as the branches with faults, the data at each end is brought into the ranging function of each branch, and the distance between the other two assumed fault points and the T node is calculated;
and step S004, comparing the distances from the three virtual fault points to the T node with the line length of the corresponding branch, if the distance from one virtual fault point to the T node is less than the line length of the branch and more than zero, the fault occurs on the branch, and the virtual fault distance of the branch is calculated to be the distance from the fault to the T node.
Preferably, in step S002, the line lengths of the MT, NT and PT branches are used, and the positive sequence voltage and current at the measurement point and the positive sequence fault voltage and current are substituted into a formula according to the positive sequence wave impedance and propagation coefficient of the line, so as to respectively solve the positive sequence voltage U at the T node iT (i = M, N, P), positive sequence fault voltage Δ U iT And a positive sequence current I injected into the T node iT Positive sequence fault current delta I iT Comprises the following steps:
wherein, U i 、ΔU i Positive sequence voltage and positive sequence fault voltage of terminal I, respectively i 、ΔI i Positive sequence current and positive sequence fault current at terminal i,/ iT The length of the circuit of the iT branch is Z, the positive sequence wave impedance of the circuit is Z, and the positive sequence propagation coefficient of the circuit is gamma.
Preferably, in step S003, assuming that the fault occurs on the MT branch, the ranging function is:
wherein the content of the first and second substances,
B 1 ＝2(U NT I PT -U PT I NT )ΔI PT Z-2(ΔU NT ΔI PT -ΔU PT ΔI NT )I PT Z，
C 1 ＝(ΔU NT ΔI PT -ΔU PT ΔI NT )U PT -(U NT I PT -U PT I NT )ΔU PT ，
A 2 ＝(ΔU PT ΔI NT -ΔU NT ΔI PT )(2U MT I NT +U NT I MT )-(U PT I NT -U NT I PT )(2ΔU MT ΔI NT +ΔU NT ΔI MT )，
B 2 ＝2(U PT I NT -U NT I PT )ΔI NT Z-2(ΔU PT ΔI NT -ΔU NT ΔI PT )I NT Z，
C 2 ＝(ΔU PT ΔI NT -ΔU NT ΔI PT )U NT -(U PT I NT -U NT I PT )ΔU NT 。
preferably, in step S003, assuming that the fault occurs on the NT branch, the ranging function is:
wherein the content of the first and second substances,
B 1 ＝2(U MT I PT -U PT I MT )ΔI PT Z-2(ΔU MT ΔI PT -ΔU PT ΔI MT )I PT Z，
C 1 ＝(ΔU MT ΔI PT -ΔU PT ΔI MT )U PT -(U MT I PT -U PT I MT )ΔU PT ，
A 2 ＝(ΔU PT ΔI MT -ΔU MT ΔI PT )(2U NT I MT +U MT I NT )-(U PT I MT -U MT I PT )(2ΔU NT ΔI MT +ΔU MT ΔI NT )，
B 2 ＝2(U PT I MT -U MT I PT )ΔI MT Z-2(ΔU PT ΔI MT -ΔU MT ΔI PT )I MT Z，
C 2 ＝(ΔU PT ΔI MT -ΔU MT ΔI PT )U MT -(U PT I MT -U MT I PT )ΔU MT 。
preferably, in step S003, assuming that the fault occurs on the PT branch, the ranging function is:
wherein, the first and the second end of the pipe are connected with each other,
B 1 ＝2(U MT I NT -U NT I MT )ΔI NT Z-2(ΔU MT ΔI NT -ΔU NT ΔI MT )I NT Z，
C 1 ＝(ΔU MT ΔI NT -ΔU NT ΔI MT )U NT -(U MT I NT -U NT I MT )ΔU NT ，
A 2 ＝(ΔU NT ΔI MT -ΔU MT ΔI NT )(2U PT I MT +U MT I PT )-(U NT I MT -U MT I NT )(2ΔU PT ΔI MT +ΔU MT ΔI PT )，
B 2 ＝2(U NT I MT -U MT I NT )ΔI MT Z-2(ΔU NT ΔI MT -ΔU MT ΔI NT )I MT Z，
C 2 ＝(ΔU NT ΔI MT -ΔU MT ΔI NT )U MT -(U NT I MT -U MT I NT )ΔU MT 。
preferably, the T-type high-voltage transmission line asynchronous fault distance measuring method further comprises an auxiliary criterion for verifying the correctness of the data, that is, the distance from the virtual fault point of the non-fault branch to the T node
Distance of fault point from T node of fault branch
Introducing an auxiliary criterion function:
wherein f is a modulus function; if f is<δ, then the calculated distance of the fault point from the T node is valid; if f is>Delta, strengthening and filtering the data of the three ends, and recalculating; when the distances from the virtual fault points on the two or three solved branches to the T node are all satisfied
When, if f<δ, then the actual fault is a T node fault; if f>Delta, the data enhancement filtering of the three ends is recalculated.
Under the ideal condition of the water-cooling device,
considering the actual transformer acquisition error, extracting fundamental wave vector error and the like, the method can lead
Close to 0 but not zero, so in practical applications a threshold δ needs to be set.When in use
When the obtained value is within the threshold range, the data of the three ends are accurate, and the distances from the fault branch and the fault point to the T node are accurate according to the ranging function; when in use
If the obtained value is not in the threshold range, the error of the data extracted from the three ends is large, and at this time, the data of the three ends are subjected to reinforced filtering and are calculated again.
Taking the case that the fault occurs on the NT branch as an example, as shown in fig. 2:
the positive sequence voltage of the T node and the positive sequence current injected into the T node have the following relations with the positive sequence voltage and the positive sequence current of the N end:
taking N-end data as a reference, the asynchronous angle of the M-end data relative to the N-end data is delta 1 The asynchronous angle of the P-end data relative to the N-end data is delta 2 And make an order
Then there is
Similarly, the positive sequence fault voltage and the positive sequence fault current injected into the T node and the positive sequence fault voltage and the positive sequence fault current at the N end have the following relations:
the distance between the fault point and the T node can be obtained through the joint type (2) and the formula (3):
wherein the content of the first and second substances,
B 1 ＝2(U MT I PT -U PT I MT )ΔI PT Z-2(ΔU MT ΔI PT -ΔU PT ΔI MT )I PT Z，
C 1 ＝(ΔU MT ΔI PT -ΔU PT ΔI MT )U PT -(U MT I PT -U PT I MT )ΔU PT ，
A 2 ＝(ΔU PT ΔI MT -ΔU MT ΔI PT )(2U NT I MT +U MT I NT )-(U PT I MT -U MT I PT )(2ΔU NT ΔI MT +ΔU MT ΔI NT )，
B 2 ＝2(U PT I MT -U MT I PT )ΔI MT Z-2(ΔU PT ΔI MT -ΔU MT ΔI PT )I MT Z，
C 2 ＝(ΔU PT ΔI MT -ΔU MT ΔI PT )U MT -(U PT I MT -U MT I PT )ΔU MT 。
when the actual fault occurs on the NT branch, there are
When the actual failure does not occur on the NT branch, but on the MT branch, as shown in fig. 3.
In the same way, there are
The distance l between the fault point and the T node can be obtained from the formula (5) Tf Is composed of
L in equation (6) due to the actual failure occurring on the MT leg Tf The distance from the actual fault to the T node is l Tf >0, the expression on the right side of the equal sign of the formula (6) is less than 0. When the expected failure occurs in the NT branch and the distance is measured by the equation (4), the comparison with the right expression having the same sign as the equation (6) is made, and the result is obtained by the equation (4)
The results are shown in formula (4) and formula (6)
Obtained by ranging on MT branches due to actual faults occurring on MT branches
Is that Tf I.e. by
When the actual fault does not occur on the MT branch but on the PT branch, the MT and PT branches are electrically symmetrical, and the same principle also exists
Supposing that the fault occurs on the MT branch, the same principle is that the distance measurement is carried out on the MT branch
Wherein, the first and the second end of the pipe are connected with each other,
A 1 ＝(ΔU NT ΔI PT -ΔU PT ΔI NT )(2U MT I PT +U PT I MT )-(U NT I PT -U PT I NT )(2ΔU MT ΔI PT +ΔU PT ΔI MT )，
B 1 ＝2(U NT I PT -U PT I NT )ΔI PT Z-2(ΔU NT ΔI PT -ΔU PT ΔI NT )I PT Z，
C 1 ＝(ΔU NT ΔI PT -ΔU PT ΔI NT )U PT -(U NT I PT -U PT I NT )ΔU PT ，
A 2 ＝(ΔU PT ΔI NT -ΔU NT ΔI PT )(2U MT I NT +U NT I MT )-(U PT I NT -U NT I PT )(2ΔU MT ΔI NT +ΔU NT ΔI MT )，
B 2 ＝2(U PT I NT -U NT I PT )ΔI NT Z-2(ΔU PT ΔI NT -ΔU NT ΔI PT )I NT Z，
C 2 ＝(ΔU PT ΔI NT -ΔU NT ΔI PT )U NT -(U PT I NT -U NT I PT )ΔU NT 。
if it is found
And satisfy
A failure occurs on the MT branch,
the distance of the fault from the T node; if obtained
The failure does not occur on the MT branch.
The supposed fault occurs on the PT branch, and the distance measurement on the PT branch is the same
Wherein the content of the first and second substances,
A 1 ＝(ΔU MT ΔI NT -ΔU NT ΔI MT )(2U PT I NT +U NT I PT )-(U MT I NT -U NT I MT )(2ΔU PT ΔI NT +ΔU NT ΔI PT )，
B 1 ＝2(U MT I NT -U NT I MT )ΔI NT Z-2(ΔU MT ΔI NT -ΔU NT ΔI MT )I NT Z，
C 1 ＝(ΔU MT ΔI NT -ΔU NT ΔI MT )U NT -(U MT I NT -U NT I MT )ΔU NT ，
A 2 ＝(ΔU NT ΔI MT -ΔU MT ΔI NT )(2U PT I MT +U MT I PT )-(U NT I MT -U MT I NT )(2ΔU PT ΔI MT +ΔU MT ΔI PT )，
B 2 ＝2(U NT I MT -U MT I NT )ΔI MT Z-2(ΔU NT ΔI MT -ΔU MT ΔI NT )I MT Z，
C 2 ＝(ΔU NT ΔI MT -ΔU MT ΔI NT )U MT -(U NT I MT -U MT I NT )ΔU MT 。
if obtained
And satisfy
The failure occurs on the PT branch,
the distance of the fault from the T node; if obtained
The failure does not occur on the PT branch.
The asynchronous fault distance measurement method for the T-shaped high-voltage transmission line integrates fault branch judgment and fault distance measurement, has no distance measurement dead zone, and has no defect of pseudo roots in the traditional asynchronous distance measurement method; the distance measurement method has no complex iterative program, can obtain the fault distance by using an analytical expression, has auxiliary criteria to judge the correctness of data, and is simple and reliable; the distance measurement method does not need to judge the fault type, is basically not influenced by transition resistance, system impedance, asynchronous angles, fault positions and the like, and has high distance measurement precision.
The invention also provides a T-shaped high-voltage transmission line asynchronous fault distance measurement system which comprises a data input module, a data extraction module, a distance measurement function calculation module and a numerical analysis module. The data input module is used for inputting voltage and current data of the measuring points at the three ends of M, N and P into the system; the data extraction module is used for filtering voltage and current data of the measuring points, extracting fundamental phasor, solving a positive sequence component and a positive sequence fault component of three ends by using a symmetric component method, and outputting the positive sequence component and the positive sequence fault component of the three ends to the ranging function calculation module; the distance measurement function calculation module is used for calculating the distance from the virtual fault point to the T node on the three branches; and the numerical analysis module is used for analyzing the distance from the supposed fault point to the T node, verifying the correctness of the data through auxiliary criteria and obtaining a fault branch and a fault distance.
Specifically, voltage and current data of three ends of M, N and P are input into the data input module, and after passing through the data extraction module, the distance measurement function calculation module calculates each branch circuitThe numerical analysis module analyzes and judges the virtual fault distance obtained by each branch circuit: if the distance between the supposed fault point and the T node is less than or equal to zero, the branch is preliminarily judged to be a non-fault branch; and if the distance from the supposed fault point to the T node is less than the line length of the branch and greater than zero, the branch is preliminarily judged to be a fault branch. The numerical analysis module also analyzes the imaginary fault distance of the non-fault branch
Distance to fault branch
Function with auxiliary criteria
If f is<δ, then outputting the fault distance and the fault branch; if f is>Delta, the data of the three ends are subjected to enhanced filtering, and the calculation is carried out again. In the numerical analysis module, when the distances from the virtual fault points on the two or three solved branches to the T node are all satisfied
When f is present<δ, then the actual fault is a T node fault; if f>Delta, recalculating the data enhancement filter of the three ends.
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.
Claims (6)
1. A T-shaped high-voltage transmission line asynchronous fault distance measuring method is characterized by comprising the following steps: the method comprises the following steps:
s001, respectively marking three ends of the T-shaped power transmission line as M, N and P, performing data filtering on voltage and current data of measuring points of the three ends M, N and P, extracting fundamental phasor, and solving positive sequence voltage and current and positive sequence fault voltage and current of the measuring points of the three ends by using a symmetric component method;
step S002, substituting the positive sequence voltage and current of the measuring point and the positive sequence fault voltage and current of the measuring point into a formula according to the positive sequence wave impedance and the propagation coefficient of the line by using the line lengths of the MT, NT and PT branches, and respectively solving the positive sequence voltage and the positive sequence fault voltage of the T node and the positive sequence current and the positive sequence fault current injected into the T node;
step S003, one of the three branches is assumed as a fault branch, a fault point on the branch is an imaginary fault point, data of each end is brought into a distance measurement function of the branch, and the distance between the imaginary fault point and a T node is calculated; in the same way, the other two branches are respectively assumed as the branches with faults, the data at each end is brought into the ranging function of each branch, and the distance between the other two assumed fault points and the T node is calculated;
and step S004, comparing the distances from the three virtual fault points to the T node with the line length of the corresponding branch, if the distance from one virtual fault point to the T node is less than the line length of the branch and more than zero, the fault occurs on the branch, and the virtual fault distance of the branch is calculated to be the distance from the fault to the T node.
2. The T-type high-voltage transmission line non-synchronous fault location method of claim 1, characterized in that: in step S002, the line lengths of the MT, NT, and PT branches are used, and the positive sequence voltage and current at the measurement point and the positive sequence fault voltage and current are substituted into a formula according to the positive sequence wave impedance and propagation coefficient of the line, so as to respectively solve the positive sequence voltage U at the T node iT I = M, N, P, positive sequence fault voltage Δ U iT And a positive sequence current I injected into the T node iT Positive sequence fault current delta I iT Comprises the following steps:
wherein, U i 、ΔU i Positive sequence voltage and positive sequence fault voltage of terminal I, respectively i 、ΔI i Positive sequence current and positive sequence fault current at terminal i,/ iT The length of the circuit of the iT branch is Z, the positive sequence wave impedance of the circuit is Z, and the positive sequence propagation coefficient of the circuit is gamma.
3. The T-type high-voltage transmission line non-synchronous fault location method of claim 1, characterized in that: in step S003, assuming that a fault occurs on the MT branch, the ranging function is:
wherein the content of the first and second substances,
B 1 ＝2(U NT I PT -U PT I NT )ΔI PT Z-2(ΔU NT ΔI PT -ΔU PT ΔI NT )I PT Z，
C 1 ＝(ΔU NT ΔI PT -ΔU PT ΔI NT )U PT -(U NT I PT -U PT I NT )ΔU PT ，
A 2 ＝(ΔU PT ΔI NT -ΔU NT ΔI PT )(2U MT I NT +U NT I MT )-(U PT I NT -U NT I PT )(2ΔU MT ΔI NT +ΔU NT ΔI MT )，
B 2 ＝2(U PT I NT -U NT I PT )ΔI NT Z-2(ΔU PT ΔI NT -ΔU NT ΔI PT )I NT Z，
C 2 ＝(ΔU PT ΔI NT -ΔU NT ΔI PT )U NT -(U PT I NT -U NT I PT )ΔU NT 。
4. the T-type high-voltage transmission line non-synchronous fault location method of claim 1, characterized in that: in step S003, assuming that a fault occurs on the NT branch, the ranging function is:
wherein the content of the first and second substances,
B 1 ＝2(U MT I PT -U PT I MT )ΔI PT Z-2(ΔU MT ΔI PT -ΔU PT ΔI MT )I PT Z，
C 1 ＝(ΔU MT ΔI PT -ΔU PT ΔI MT )U PT -(U MT I PT -U PT I MT )ΔU PT ，
A 2 ＝(ΔU PT ΔI MT -ΔU MT ΔI PT )(2U NT I MT +U MT I NT )-(U PT I MT -U MT I PT )(2ΔU NT ΔI MT +ΔU MT ΔI NT )，
B 2 ＝2(U PT I MT -U MT I PT )ΔI MT Z-2(ΔU PT ΔI MT -ΔU MT ΔI PT )I MT Z，
C 2 ＝(ΔU PT ΔI MT -ΔU MT ΔI PT )U MT -(U PT I MT -U MT I PT )ΔU MT ；
in step S003, assuming that a fault occurs on the PT branch, the ranging function is:
wherein, the first and the second end of the pipe are connected with each other,
B 1 ＝2(U MT I NT -U NT I MT )ΔI NT Z-2(ΔU MT ΔI NT -ΔU NT ΔI MT )I NT Z，
C 1 ＝(ΔU MT ΔI NT -ΔU NT ΔI MT )U NT -(U MT I NT -U NT I MT )ΔU NT ，
A 2 ＝(ΔU NT ΔI MT -ΔU MT ΔI NT )(2U PT I MT +U MT I PT )-(U NT I MT -U MT I NT )(2ΔU PT ΔI MT +ΔU MT ΔI PT )，
B 2 ＝2(U NT I MT -U MT I NT )ΔI MT Z-2(ΔU NT ΔI MT -ΔU MT ΔI NT )I MT Z，
C 2 ＝(ΔU NT ΔI MT -ΔU MT ΔI NT )U MT -(U NT I MT -U MT I NT )ΔU MT 。
5. the T-shaped high-voltage transmission line asynchronous fault distance measuring method according to claim 1, characterized in that: the method for measuring the distance of the asynchronous fault of the T-shaped high-voltage transmission line also comprises an auxiliary criterion for verifying the correctness of data, namely the distance between an imaginary fault point of a non-fault branch and a T node
Distance of fault point from T node of fault branch
Introducing an auxiliary criterion function:
wherein f is a modulo function; if f is<δ, δ being a threshold value close to 0 but not equal to 0, then the calculated distance of the point of failure from the T node is valid; if f is>Delta, strengthening and filtering the data of the three ends, and recalculating; when the distances from the virtual fault points on the two or three solved branches to the T node are all satisfied
When, if f<δ, then the actual fault is a T node fault; if f>Delta, the data enhancement filtering of the three ends is recalculated.
6. The utility model provides a T type high tension transmission line asynchronous fault ranging system which characterized in that: the system comprises a data input module, a data extraction module, a ranging function calculation module and a numerical analysis module, wherein the data input module is used for inputting voltage and current data of measuring points at three ends of M, N and P into the system; the data extraction module is used for filtering voltage and current data of the measuring points, extracting fundamental phasor, solving a positive sequence component and a positive sequence fault component of three ends by using a symmetric component method, and outputting the positive sequence component and the positive sequence fault component of the three ends to the ranging function calculation module; the distance measurement function calculation module is used for calculating the distance from the virtual fault point on the three branches to the T node; and the numerical analysis module is used for analyzing the distance from the supposed fault point to the T node, verifying the correctness of the data through auxiliary criteria and obtaining a fault branch and a fault distance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010680858.2A CN111781468B (en) | 2020-07-15 | 2020-07-15 | Asynchronous fault distance measurement method and system for T-shaped high-voltage transmission line |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010680858.2A CN111781468B (en) | 2020-07-15 | 2020-07-15 | Asynchronous fault distance measurement method and system for T-shaped high-voltage transmission line |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111781468A CN111781468A (en) | 2020-10-16 |
| CN111781468B true CN111781468B (en) | 2022-11-22 |
Family
ID=72767888
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010680858.2A Active CN111781468B (en) | 2020-07-15 | 2020-07-15 | Asynchronous fault distance measurement method and system for T-shaped high-voltage transmission line |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111781468B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114047408B (en) * | 2022-01-17 | 2022-03-29 | 广东电网有限责任公司佛山供电局 | High-precision fault location method for power transmission line and related device |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105652151A (en) * | 2015-12-30 | 2016-06-08 | 武汉大学 | Line parameter detection and data non synchronous verification-based double-end ranging method |
| CN105929302A (en) * | 2016-04-13 | 2016-09-07 | 上海交通大学 | Sequence component relation based range finding method for single-end fault of power transmission line |
| CN107202936A (en) * | 2017-05-04 | 2017-09-26 | 许继集团有限公司 | A kind of T-link fault distance measurement |
| CN107271841A (en) * | 2017-05-27 | 2017-10-20 | 天津大学 | The T-shaped fault positioning method for transmission line of common-tower double-return based on forward-order current difference |
| CN108362978A (en) * | 2018-03-08 | 2018-08-03 | 国网山东省电力公司滨州供电公司 | A kind of T-type power transmission line fault locating method based on range function phase characteristic |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2397503C2 (en) * | 2005-09-14 | 2010-08-20 | Абб Текнолоджи Аг | Method of determining point of fault in power line |
-
2020
- 2020-07-15 CN CN202010680858.2A patent/CN111781468B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105652151A (en) * | 2015-12-30 | 2016-06-08 | 武汉大学 | Line parameter detection and data non synchronous verification-based double-end ranging method |
| CN105929302A (en) * | 2016-04-13 | 2016-09-07 | 上海交通大学 | Sequence component relation based range finding method for single-end fault of power transmission line |
| CN107202936A (en) * | 2017-05-04 | 2017-09-26 | 许继集团有限公司 | A kind of T-link fault distance measurement |
| CN107271841A (en) * | 2017-05-27 | 2017-10-20 | 天津大学 | The T-shaped fault positioning method for transmission line of common-tower double-return based on forward-order current difference |
| CN108362978A (en) * | 2018-03-08 | 2018-08-03 | 国网山东省电力公司滨州供电公司 | A kind of T-type power transmission line fault locating method based on range function phase characteristic |
Non-Patent Citations (3)
| Title |
|---|
| "Improving the Accuracy of Fault Detection Location";A. Lipsky1 等;《EuroCon 2013*1-4 July 2013 * Zagreb, Croatia》;IEEE;20131010;第731-736页 * |
| "T 型输电线路非同步数据";施世鸿 等;《电力自动化设备》;20081031;第28卷(第10期);第63-66页 * |
| "基于相位特性的高压输电线路双端非同步故障测距算法";陈旭 等;《电力***自动化》;20151125;第35卷(第22期);第152-155页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111781468A (en) | 2020-10-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105738769B (en) | Series compensation double line down localization method based on distributed parameter model | |
| CN108802564B (en) | distribution network T-shaped line parameter-independent fault location algorithm and system | |
| CN107817420B (en) | Non-synchronous data fault location method for non-whole-course same-tower double-circuit power transmission line | |
| CN105137281A (en) | Hybrid line fault point positioning method based on single-end electric quantity and transient traveling wave comprehensive characteristic analysis | |
| CN105548719A (en) | Detection circuit and method of grounding insulation resistors | |
| CN111077471A (en) | NPC three-level inverter open-circuit fault diagnosis method based on instantaneous frequency | |
| Radojevic et al. | Smart overhead lines autoreclosure algorithm based on detailed fault analysis | |
| CN111781468B (en) | Asynchronous fault distance measurement method and system for T-shaped high-voltage transmission line | |
| CN108845225B (en) | Method for analyzing wiring correctness of secondary current loop of power capacitor and reactor | |
| CN110780149A (en) | Identification of faulty sections of a power transmission line | |
| CN110927519A (en) | Active power distribution network fault positioning method based on mu PMU measurement value | |
| Taheri et al. | Single-end current-based algorithm for fault location in series capacitor compensated transmission lines | |
| CN110308366A (en) | A kind of harmonic source location method based on orthogonal matching pursuit algorithm | |
| CN109309380A (en) | Adaptive three_phase reclosing method and system based on shunt reactor current characteristic | |
| CN109270406B (en) | Method for calculating transition resistance based on double-end asynchronous electrical quantity | |
| CN109270405B (en) | Zero sequence parameter calculation method and system based on double-circuit line characteristic equation | |
| CN112363009B (en) | Single-ended fault location method and system for same-tower line ground fault | |
| Suonan et al. | An accurate fault location algorithm based on parameter identification of linear differential equation using one terminal data | |
| He et al. | Modified single-ended fault location method for single-phase-to-ground faults in T-connected line | |
| CN111796165A (en) | Power distribution network fault positioning method based on self-adaptive Fourier transform | |
| CN105548803A (en) | Weighted least square algorithm-based ultra-high voltage transmission line fault positioning method | |
| CN115469194B (en) | Single-phase earth fault distance measurement method based on n-type equivalent circuit model single-end quantity | |
| CN110286283A (en) | Micro-grid island detection method and system | |
| Zhijian et al. | New live line measurement methods of transmission lines' inductance parameters based on GPS | |
| CN105242113B (en) | A kind of short-circuit test circuit asymmetrical three-phase impedance determines 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 |