CN110456226B - Fault location system of power transmission line - Google Patents
Fault location system of power transmission line Download PDFInfo
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- CN110456226B CN110456226B CN201910779752.5A CN201910779752A CN110456226B CN 110456226 B CN110456226 B CN 110456226B CN 201910779752 A CN201910779752 A CN 201910779752A CN 110456226 B CN110456226 B CN 110456226B
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- 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
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- 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
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- 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
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- 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
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Abstract
The invention provides a fault location system of a power transmission line, which comprises: the wave recording device is positioned at a measuring point of the power transmission line and is used for acquiring a reclosing three-phase voltage traveling wave or a reclosing three-phase current traveling wave; the processor is connected with the wave recording device and is used for constructing a line mode traveling wave containing a fault phase and a line mode traveling wave consisting of a non-fault phase according to the three-phase voltage traveling wave or the three-phase current traveling wave; determining the superposition component of the reclosing line mode traveling wave at the fault point according to the line mode traveling wave containing the fault phase and the line mode traveling wave formed by the non-fault phase; determining the distance between the fault point and the measuring point according to the superposition component of the reclosing line mode travelling wave at the fault point and the reclosing moment; and the display device is connected with the processor and is used for displaying the distance of the fault point of the power transmission line. The system of the invention can quickly and accurately locate the fault point, reduce the line patrol burden, and the fault location result is not affected by the branch point of the line, the transition resistance, the change of the system operation mode and the load.
Description
Technical Field
The invention relates to the technical field of power systems, in particular to a fault location system of a power transmission line.
Background
The high-voltage transmission line is an important component of an electric power system and is an important task of transmitting electric energy, meanwhile, the high-voltage transmission line is also a frequent part of a power grid fault, and in recent years, the proportion of the high-voltage transmission line fault in various electric equipment of the electric power system is increased. Due to the complex line corridor condition, the high-voltage transmission line needs to frequently pass through remote zones such as farmlands, forests, mountainous areas and the like, and the difficulty of manual line patrol and fault first-aid repair is high after a fault occurs. Therefore, when a fault occurs, the fault point is quickly and accurately positioned, the fault can be timely eliminated, the power failure time is shortened, the economic loss caused by power failure is effectively reduced, the line patrol burden can be reduced, manpower and material resources are saved, and the method has a very positive effect on the safe and economic operation of the whole power system.
The fault types of the high-voltage transmission line are divided into four types, namely a single-phase grounding short-circuit fault, a two-phase grounding short-circuit fault and a three-phase short-circuit fault. According to the operation experience and the statistics of the years, in various short-circuit faults of the power transmission line, the single-phase grounding short-circuit fault accounts for more than 80% of the total faults of the line, the two-phase short-circuit fault and the two-phase grounding short-circuit fault only account for 3% -5% of the total faults, and the proportion of the three-phase short-circuit fault is less than 1%. From the above statistics, it can be seen that the proportion of ground faults is the highest. At present, fault location is generally carried out by adopting a single-ended impedance method on site, but because the single-ended power frequency electric quantity is only utilized, the influence of transition resistance on a location result cannot be overcome in principle. The double-ended impedance rule can utilize double-ended electrical quantity, and although the problem that the single-ended impedance method is influenced by a transition resistor and a system operation mode is solved, the requirement on data synchronization is high, and the investment on hardware equipment is high.
In summary, after a single-phase connection fault occurs in a power transmission line, how to quickly and accurately locate the fault point without being affected by a branch point of the line, a transition resistor, a change in a system operation mode and a load, and meanwhile, avoiding high investment cost of hardware is a problem that needs to be solved at present.
Disclosure of Invention
The present invention is directed to solving at least one of the problems of the prior art or the related art.
Therefore, the invention provides a fault location system of a power transmission line.
In view of this, a fault location system for a power transmission line is provided, which is suitable for a reclosing device to reclose after the power transmission line has a single-phase fault, and is characterized in that the fault location system comprises: the wave recording device is positioned at a measuring point of the power transmission line and is used for acquiring a reclosing three-phase voltage traveling wave or a reclosing three-phase current traveling wave; the processor is connected with the wave recording device and is used for constructing a line mode traveling wave containing a fault phase and a line mode traveling wave consisting of a non-fault phase according to the three-phase voltage traveling wave or the three-phase current traveling wave; determining the superposition component of the reclosing line mode traveling wave at the fault point according to the line mode traveling wave formed by the line mode traveling wave containing the fault phase and the line mode traveling wave formed by the non-fault phase; determining the distance between the fault point and the measuring point according to the superposition component of the reclosing line mode travelling wave at the fault point and the reclosing moment; and the display device is connected with the processor and is used for displaying the distance of the fault point of the power transmission line.
According to the fault location system of the power transmission line, when the power transmission line has a single-phase fault, the reclosing device can automatically execute reclosing operation, after the reclosing device carries out reclosing, a three-phase voltage traveling wave or a three-phase current traveling wave of the reclosing is collected at a measuring point through the wave recording device, the processor generates a line mode traveling wave containing a fault phase and a line mode traveling wave formed by a non-fault phase according to the three-phase voltage traveling wave or the three-phase current traveling wave, determines the superposed component of the reclosing line mode traveling wave at the fault point, determines the distance between the fault point and the measuring point according to the superposed component of the reclosing line mode traveling wave at the fault point and the reclosing moment, and displays fault point distance data through the display device. Through above-mentioned fault location system, can accurately obtain transmission line single-phase earth fault distance fast, alleviate the line inspection burden, the material resources of using manpower sparingly are favorable to troubleshooting with higher speed and the recovery power supply, reduce the loss that the power failure brought, and fault location result is not influenced by circuit branch point, transition resistance, system operation mode change and load, can the accurate fault point position of confirming. Meanwhile, the fault location does not need to additionally install injection equipment, the hardware investment is low, the fault location method is suitable for both voltage traveling waves and current traveling waves, the application range is wide, normal line single-phase superposition wave recording data is not needed in the location process, the impact on a power grid is small, and the stability and the reliability of a location system are favorably improved.
In addition, according to the fault location system of the power transmission line in the above technical solution provided by the present invention, the following additional technical features may also be provided:
in the above technical solution, preferably, the method further includes: the power supply is used for providing electric energy for a fault distance measuring system of the power transmission line; the prompting device is connected with the processor and used for sending the distance between the fault point and the measuring point through a short message; and the filtering device is connected with the processor and is used for carrying out noise reduction treatment on the line mode traveling wave containing the fault phase and the line mode traveling wave formed by the non-fault phase.
In the technical scheme, the detected fault point distance can be sent to the mobile terminal of related workers in a short message mode at the first time through the prompting device, acceleration of troubleshooting and power restoration are facilitated, loss caused by power failure is reduced, the filtering device can perform noise reduction treatment on the line mode traveling wave containing a fault phase and the line mode traveling wave formed by a non-fault phase, the accuracy of detection data is guaranteed, the fault point position is rapidly and accurately determined, line patrol burden is reduced, and manpower and material resources are saved.
In any of the above technical solutions, preferably, the processor is specifically configured to: carrying out fault phase selection on the three-phase voltage traveling wave or the three-phase current traveling wave, and determining a fault phase and a non-fault phase of the power transmission line; and carrying out phase-mode conversion processing according to the fault phase and the non-fault relative three-phase voltage traveling wave or the three-phase current traveling wave to obtain the line-mode traveling wave containing the fault phase and the line-mode traveling wave formed by the non-fault phase.
According to the technical scheme, the fault phase selection is carried out on the three-phase voltage traveling wave or the three-phase current traveling wave, the fault phase and the non-fault phase are determined, the a-phase grounding fault is taken as an example, namely the a-phase is taken as the fault phase, the three-phase voltage traveling wave or the three-phase current traveling wave is subjected to phase-mode conversion processing according to the fault phase selection result, and the line-mode traveling wave comprising the fault phase and the line-mode traveling wave comprising the non-fault phase are obtained, so that the superposition component of the reclosing line-mode traveling wave at the fault point is determined according to the line-mode traveling wave comprising the fault phase and the line-mode traveling wave comprising the non-fault phase, the distance of the fault point is calculated, the line inspection burden is reduced, manpower and material resources are saved, the fault maintenance and.
In any of the above technical solutions, preferably, the following formula is adopted to perform phase-mode conversion processing on the three-phase voltage traveling wave or the three-phase current traveling wave, taking the a-phase grounding fault as an example:
Yα＝Ua-Ubor Yα＝Ia-Ib
Yγ＝Ub-UcOr Yγ＝Ib-Ic
Wherein, a phase is fault phase, b and c phases are non-fault phases, YαRepresenting line-mode travelling waves, Y, containing faulted phasesγLine mode travelling wave, U, representing the constitution of a non-faulted phaseaRepresenting a travelling wave, U, of the phase voltage ab、UcRepresents a traveling wave of the voltages of b and c phases, IaRepresents a traveling wave of a-phase current, Ib、IcThe b-phase current traveling wave and the c-phase current traveling wave are shown, respectively.
In the technical scheme, when a single-phase ground fault occurs in a power transmission line, taking an a-phase ground fault as an example, namely the a-phase is a fault phase, the b-phase and c-phase are non-fault phases, namely the a-phase voltage traveling wave is a fault phase voltage traveling wave, the b-phase voltage traveling wave and the c-phase voltage traveling wave are non-fault phase voltage traveling waves, the a-phase current traveling wave is a fault phase current traveling wave, and the b-phase and c-phase current traveling waves are non-fault phase current traveling waves.
Specifically, the Karenbauer (Kerenbel) transformation is used for phase-mode transformation, so that three-phase decoupling is realized.
In any of the above technical solutions, preferably, the processor is further configured to: respectively carrying out normalization processing on the line mode traveling wave containing the fault phase and the line mode traveling wave formed by the non-fault phase; and determining the superposition component of the reclosing line mode traveling wave at the fault point according to the normalized line mode traveling wave containing the fault phase and the normalized line mode traveling wave consisting of the non-fault phase.
In the technical scheme, the line mode traveling wave containing the fault phase and the line mode traveling wave composed of the non-fault phase are respectively subjected to normalization processing, and the superposition component of the reclosing line mode traveling wave at the fault point is calculated according to the normalized line mode traveling wave containing the fault phase and the normalized line mode traveling wave composed of the non-fault phase. The line mode network with fault phase contains fault point to ground branch, so the propagation of line mode travelling wave is affected by fault point. Therefore, according to the superposition principle, the superposition component of the reclosing line mode travelling wave can be constructed by utilizing the difference between the travelling waves in the two different line mode networks, the superposition component only reflects the refraction and reflection conditions of the reclosing line mode travelling wave at a fault point, the propagation characteristic of the superposition component is not interfered by a discontinuous wave impedance point, the method does not need to carry out reclosing recording on a normal line, and therefore data storage and data alignment are not needed, and unnecessary impact of reclosing of the normal line on a power grid can be reduced.
In any of the above technical solutions, preferably, the following formula is adopted to perform normalization processing on the line mode traveling wave including the fault phase and the line mode traveling wave composed of the non-fault phase respectively:
wherein, YαRepresenting line-mode travelling waves, M, containing faulted phasesαRepresenting the first modal maximum, Y, of a line-mode travelling wave containing a faulted phaseγLine mode travelling wave, M, representing the constitution of a non-faulted phaseγRepresenting the first modal maximum of the line-mode traveling wave formed by the non-faulted phase,
represents the normalized line mode traveling wave containing the fault phase,
and expressing the line mode travelling wave formed by the normalized non-fault phase.
In the technical scheme, the line mode traveling wave containing the fault phase is normalized according to the first modulus maximum value of the line mode traveling wave containing the fault phase and the line mode traveling wave containing the fault phase, and the line mode traveling wave containing the non-fault phase is normalized according to the line mode traveling wave containing the non-fault phase and the first modulus maximum value of the line mode traveling wave containing the non-fault phase, so that the superposition component only reflecting fault point information is calculated according to the normalized line mode traveling wave containing the fault phase and the normalized line mode traveling wave containing the non-fault phase.
In any of the above technical solutions, preferably, the following formula is adopted to determine the superimposed component of the reclosing line mode traveling wave at the fault point:
wherein the content of the first and second substances,
showing the superimposed components of the reclosing line mode travelling wave at the fault point,
represents the normalized line mode traveling wave containing the fault phase,
and expressing the line mode travelling wave formed by the normalized non-fault phase.
In the technical scheme, according to the superposition principle, the superposition component of the reclosing line-mode traveling wave only at the fault point is constructed through the normalized line-mode traveling wave containing the fault phase and the normalized line-mode traveling wave consisting of the non-fault phase, so that in the process of ranging, reclosing recording is not needed on a normal line, data storage and data alignment are not needed, and unnecessary impact of reclosing on the normal line on a power grid can be reduced.
In any of the above technical solutions, preferably, the processor is further configured to: and respectively carrying out wavelet transformation on the line mode traveling wave containing the fault phase and the line mode traveling wave consisting of the non-fault phase to obtain a first modulus maximum value of the line mode traveling wave containing the fault phase and a first modulus maximum value of the line mode traveling wave consisting of the non-fault phase.
In the technical scheme, the amplitude values of the line mode traveling wave containing the fault phase and formed by the non-fault phase after the phase-mode transformation are different, so that the line mode traveling wave containing the fault phase and formed by the non-fault phase are respectively subjected to wavelet transformation to obtain a first mode maximum value after the wavelet transformation, and then the line mode traveling wave containing the fault phase and formed by the non-fault phase are subjected to normalization processing according to the first mode maximum value to obtain a superposition component only reflecting fault point information, so that in the process of ranging, reclosing recording is not required to be carried out on a normal line, data storage and data alignment are not required, and unnecessary impact of reclosing of the normal line on a power grid can be reduced.
In any of the above technical solutions, preferably, the line mode traveling wave including the faulty phase and the line mode traveling wave including the non-faulty phase are respectively subjected to wavelet transformation by using the following formulas:
wherein f (n) represents data points of the line mode traveling wave containing the fault phase or the line mode traveling wave consisting of the non-fault phase, n is a sampling point,
representing the approximation component of the j-th scale,
wavelet components representing the j-th scale, h (k), g (k) representing filter parameters, j being the scale, k being the data point currently processed, k being a positive integer, η being the construction coefficient.
And determining the modulus maximum value after wavelet transformation by adopting the following formula:
wherein the content of the first and second substances,
modulus of wavelet transform representing j-th scaleMaximum value, nkRepresenting the kth point data in the current scale,
the wavelet component of the j-th scale representing the kth point data in the current scale.
In this technical scheme, carry out wavelet transform through above formula, can reduce the error of transmission line single-ended travelling wave range finding, guarantee the accuracy of fault point range finding to reduce the use of additionally installing injection device additional, the hardware investment is few, does not need normal circuit coincidence record ripples data moreover, and is little to the electric wire netting impact, has good practicality and economic performance.
In any of the above technical solutions, preferably, the distance between the fault point and the measurement point is determined by using the following formula:
where x denotes the distance between the fault point and the measurement point, t1Indicating the reclosing time, t2And v represents the line mode wave velocity of the voltage or current traveling wave.
In the technical scheme, the distance between the fault point and the measuring point is calculated according to the reclosing time, the time corresponding to the first module maximum value of the superposition component of the reclosing line mode traveling wave at the fault point, namely the arrival time of the reflected wave at the first fault point and the line mode wave speed of the three-phase voltage traveling wave or the three-phase current traveling wave, thereby quickly and accurately positioning the fault point, reducing the burden of line patrol, facilitating the acceleration of fault maintenance and the recovery of power supply, reducing the loss caused by power failure, and the fault location result is not affected by the branch point of the circuit, the transition resistance, the change of the system operation mode and the load, meanwhile, the fault location does not need to additionally install injection equipment, the hardware investment is less, the method is suitable for both voltage traveling waves and current traveling waves, has wide application range, does not need normal line single-phase coincident wave recording data in the ranging process, has small impact on a power grid, and is favorable for improving the stability and the reliability of a ranging system.
Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.
Drawings
The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
fig. 1 shows a schematic block diagram of a fault location system of a power transmission line of an embodiment of the invention;
FIG. 2 shows a schematic diagram of a line-mode network with a failed phase according to an embodiment of the present invention;
FIG. 3 shows a line-mode network schematic of a non-faulted phase configuration of one embodiment of the present invention;
FIG. 4 shows a point of failure superimposed component network schematic of one embodiment of the present invention;
FIG. 5 is a diagram illustrating a T-connection power transmission line model according to an embodiment of the present invention;
FIG. 6 illustrates a reclosing three-phase voltage traveling wave schematic diagram of an embodiment of the invention;
FIG. 7 shows a line mode traveling wave with a failed phase and a line mode traveling wave with a non-failed phase according to an embodiment of the present invention;
fig. 8 is a schematic diagram illustrating superimposed components of a normalized line-mode traveling wave including a fault phase, a normalized line-mode traveling wave including a non-fault phase, and a reclosing line-mode traveling wave at a fault point according to an embodiment of the present invention;
FIG. 9 is a schematic diagram illustrating wavelet transforms and modulo maxima of a normalized line-mode traveling wave with a faulted phase and a normalized line-mode traveling wave with a non-faulted phase according to an embodiment of the present invention;
fig. 10 is a schematic diagram illustrating wavelet transformation and modulo maximum of the superimposed components of the reclosing line modal traveling wave at the fault point according to an embodiment of the present invention.
Detailed Description
In order that the above objects, features and advantages of the present invention can be more clearly understood, a more particular description of the invention will be rendered by reference to the appended drawings. It should be noted that the embodiments of the present invention and features of the embodiments may be combined with each other without conflict.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited to the specific embodiments disclosed below.
An embodiment of the present invention provides a fault location system 100 for a power transmission line, which is suitable for a reclosing device to reclose after a single-phase fault occurs in the power transmission line, and as shown in fig. 1, the system includes: a recording device 102, a processor 104 and a display device 106.
Specifically, the wave recording device 102 is located at a measurement point of the power transmission line and is used for collecting a reclosing three-phase voltage traveling wave or a three-phase current traveling wave; the processor 104 is connected with the wave recording device 102 and is used for constructing a line mode traveling wave containing a fault phase and a line mode traveling wave consisting of a non-fault phase according to the three-phase voltage traveling wave or the three-phase current traveling wave; determining the superposition component of the reclosing line mode traveling wave at a fault point; determining the distance between the fault point and the measuring point according to the superposition component of the reclosing line mode travelling wave at the fault point and the reclosing moment; and the display device 106 is connected with the processor 104 and is used for displaying the fault point distance of the power transmission line.
In the fault location system 100 for the power transmission line provided in this embodiment, when a single-phase fault occurs in the power transmission line, the reclosing apparatus automatically performs a reclosing operation, after the reclosing operation is performed by the reclosing apparatus, a three-phase voltage traveling wave or a three-phase current traveling wave of the reclosing is collected at a measurement point by the wave recording apparatus 102, the processor 104 generates a line mode traveling wave including a fault phase and a line mode traveling wave including a non-fault phase according to the three-phase voltage traveling wave or the three-phase current traveling wave, determines a superimposed component of the reclosing line mode traveling wave at a fault point, determines a distance between the fault point and the measurement point according to the superimposed component of the reclosing line mode traveling wave at the fault point and a reclosing time, and displays fault point distance data by the display apparatus 106, wherein the reclosing line mode traveling wave is the line mode traveling wave of the reclosing apparatus, the line mode traveling wave including the fault phase is the line mode traveling wave, the line-mode traveling wave composed of the non-faulty phase is a line-mode traveling wave composed of only the non-faulty phase. Through the fault location system, the single-phase earth fault distance of the power transmission line can be quickly and accurately obtained, the fault location system is favorable for accelerating troubleshooting and recovering power supply, the loss caused by power failure is reduced, the line inspection burden is reduced, manpower and material resources are saved, the fault location result is not influenced by a line branch point, transition resistance, system operation mode change and load, and the position of a fault point can be accurately determined. Meanwhile, the fault location does not need to additionally install injection equipment, the hardware investment is low, the fault location method is suitable for both voltage traveling waves and current traveling waves, the application range is wide, normal line superposition wave recording data are not needed in the location process, the impact on a power grid is small, and the stability and the reliability of a location system are favorably improved.
In a specific embodiment, the wave recording device 102 records high-frequency transient traveling wave information of the reclosure, and the sampling rate is greater than or equal to 1 MHz.
In one embodiment of the present invention, as shown in fig. 1, a fault location system 100 of a power transmission line includes: a recording device 102, a processor 104, a display device 106, a power supply 108, a prompting device 110 and a filtering device 112.
Specifically, the power supply 108 is configured to provide power for the fault location system 100 of the power transmission line; the prompting device 110 is connected with the processor 104 and is used for sending the distance between the fault point and the measuring point through a short message; and a filtering device 112, connected to the processor 104, for performing noise reduction processing on the line mode traveling wave including the fault phase and the line mode traveling wave including the non-fault phase.
In this embodiment, can send the fault point distance that detects to relevant staff's mobile terminal through the mode of SMS very first time through suggestion device 110 on, be favorable to with higher speed troubleshooting and resume the power supply, reduce the loss that the power failure brought, filter device 112 can carry out the noise reduction to the line mode travelling wave that contains the line mode travelling wave of trouble looks and the line mode travelling wave that non-trouble looks constitute, guarantees the degree of accuracy of detected data to confirm the fault point position fast accurately, alleviate the burden of patrolling the line, save manpower and materials.
In an embodiment of the present invention, preferably, the processor 104 is specifically configured to: carrying out fault phase selection on the three-phase voltage traveling wave or the three-phase current traveling wave, and determining a fault phase and a non-fault phase of the power transmission line; and carrying out phase-mode conversion processing according to the fault phase and the non-fault relative three-phase voltage traveling wave or the three-phase current traveling wave to obtain the line-mode traveling wave containing the fault phase and the line-mode traveling wave formed by the non-fault phase.
Preferably, the phase-mode conversion processing is performed on the three-phase voltage or current traveling wave by the following formula, taking the phase-to-ground fault as an example:
Yα＝Ua-Ubor Yα＝Ia-Ib
Yγ＝Ub-UcOr Yγ＝Ib-Ic
Wherein, a phase is fault phase, b and c phases are non-fault phases, YαRepresenting line-mode travelling waves, Y, containing faulted phasesγLine mode travelling wave, U, representing the constitution of a non-faulted phaseaRepresenting a travelling wave, U, of the phase voltage ab、UcRepresents a traveling wave of the voltages of b and c phases, IaRepresents a traveling wave of a-phase current, Ib、IcThe b-phase current traveling wave and the c-phase current traveling wave are shown, respectively.
In this embodiment, as shown in fig. 6 and 7, when a single-phase ground fault occurs in the power transmission line, a fault phase and a non-fault phase are determined by performing fault phase selection on a three-phase voltage traveling wave or a three-phase current traveling wave, where an a-phase ground fault is taken as an example, that is, the a-phase is a fault phase, and the b-phase and the c-phase are non-fault phases, and according to a result of the fault phase selection, phase-mode conversion processing is performed on the three-phase voltage traveling wave or the three-phase current traveling wave to obtain a line-mode traveling wave including the fault phase and a line-mode traveling wave including the non-fault phase, so that a superimposed component of a reclosing line-mode traveling wave at a fault point is determined subsequently according to the line-mode traveling wave including the fault phase and the line-mode traveling wave including the non-fault phase, thereby calculating a distance of the fault point, reducing a line patrol burden, saving manpower and material resources, facilitating acceleration of troubleshooting and power restoration, the method is suitable for both voltage traveling waves and current traveling waves, and has a wide application range, wherein the line mode network containing the fault phase is shown in figure 2, and the line mode network formed by the non-fault phase is shown in figure 3.
In the specific embodiment, the phase-mode conversion is performed by using the Karenbauer (Kerenbel) conversion, so that three-phase decoupling is realized.
In an embodiment of the present invention, preferably, the processor 104 is further specifically configured to: respectively carrying out normalization processing on the line mode traveling wave containing the fault phase and the line mode traveling wave formed by the non-fault phase; and determining the superposition component of the reclosing line mode traveling wave at the fault point according to the normalized line mode traveling wave containing the fault phase and the normalized line mode traveling wave consisting of the non-fault phase.
Preferably, the line mode traveling wave including the fault phase and the line mode traveling wave including the non-fault phase are normalized by the following formula:
wherein, YαRepresenting line-mode travelling waves, M, containing faulted phasesαRepresenting the first modal maximum, Y, of a line-mode travelling wave containing a faulted phaseγLine mode travelling wave, M, representing the constitution of a non-faulted phaseγRepresenting the first modal maximum of the line-mode traveling wave formed by the non-faulted phase,
represents the normalized line mode traveling wave containing the fault phase,
and expressing the line mode travelling wave formed by the normalized non-fault phase.
And calculating the superposition component only reflecting the fault point information according to the normalized line mode traveling wave containing the fault phase and the normalized line mode traveling wave consisting of the non-fault phase.
Preferably, the superimposed component of the reclosing line mode travelling wave at the fault point is determined by the following formula:
wherein the content of the first and second substances,
showing the superimposed components of the reclosing line mode travelling wave at the fault point,
represents the normalized line mode traveling wave containing the fault phase,
and expressing the line mode travelling wave formed by the normalized non-fault phase.
In this embodiment, as shown in fig. 9, the line-mode traveling wave including the faulty phase is normalized based on the first modulo maximum values of the line-mode traveling wave including the faulty phase and the line-mode traveling wave including the faulty phase, the line-mode traveling wave including the non-faulty phase is normalized based on the first modulo maximum values of the line-mode traveling wave including the non-faulty phase and the line-mode traveling wave including the non-faulty phase, and the superimposed component reflecting only the fault point information is calculated based on the normalized line-mode traveling wave including the faulty phase and the normalized line-mode traveling wave including the non-faulty phase, where the fault point superimposed component network is as shown in fig. 4.
In an embodiment of the present invention, preferably, the processor 104 is further specifically configured to: and respectively carrying out wavelet transformation on the line mode traveling wave containing the fault phase and the line mode traveling wave consisting of the non-fault phase to obtain a first modulus maximum value of the line mode traveling wave containing the fault phase and a first modulus maximum value of the line mode traveling wave consisting of the non-fault phase.
Preferably, the line mode travelling wave containing the fault phase and the line mode travelling wave composed of the non-fault phase are respectively subjected to wavelet transformation by the following formula:
wherein f (n) represents data points of the line mode traveling wave containing the fault phase or the line mode traveling wave consisting of the non-fault phase, n is a sampling point,
representing the approximation component of the j-th scale,
wavelet components representing the j-th scale, h (k), g (k) representing filter parameters, j being the scale, k being the data point currently processed, k being a positive integer, η being the construction coefficient.
Preferably, the wavelet transformed modulus maxima are determined by the following formula:
wherein the content of the first and second substances,
modulus maximum, n, representing the wavelet transform of the j-th scalekRepresenting the kth point data in the current scale,
the wavelet component of the j-th scale representing the kth point data in the current scale.
In this embodiment, since the amplitude of the line-mode traveling wave including the faulty phase and the line-mode traveling wave including the non-faulty phase after the phase-mode transformation is different from that of the line-mode traveling wave including the faulty phase and the line-mode traveling wave including the non-faulty phase, respectively, the wavelet transformation is performed on the line-mode traveling wave including the faulty phase and the line-mode traveling wave including the non-faulty phase to obtain the first modulo maximum value after the wavelet transformation, as shown in fig. 8, and then the line-mode traveling wave including the faulty phase and the line-mode traveling wave including the non-faulty phase are normalized according to the first modulo maximum value to obtain the superimposed component that only reflects the fault point information, so that in the process of performing the distance measurement, the normal line does not need to be re-recorded with the waves, and thus, data.
In one embodiment of the present invention, preferably, the distance between the fault point and the measurement point is determined by the following formula:
where x denotes the distance between the fault point and the measurement point, t1Indicating the reclosing time, t2And v represents the linear mode wave speed of the three-phase voltage traveling wave or the three-phase current traveling wave.
According to the technical scheme, the distance between the fault point and the measuring point is calculated according to the reclosing time, the time corresponding to the first module maximum value of the superposition component of the reclosing line mode traveling wave at the fault point, namely the arrival time of the reflected wave of the first fault point and the line mode wave speed of the three-phase voltage traveling wave or the three-phase current traveling wave. The fault point can be accurately positioned fast, the line patrol burden is reduced, the acceleration of troubleshooting and power restoration are facilitated, the loss caused by power failure is reduced, the fault location result is not affected by a branch point of a line, transition resistance and the change of a system operation mode and the load, meanwhile, the fault location does not need to be additionally provided with injection equipment, the hardware investment is low, the fault location method is suitable for both voltage traveling waves and current traveling waves, the application range is wide, normal line superposition wave recording data is not needed, and the impact on a power grid is small.
In a specific embodiment of the present invention, a Power Systems Computer Aided Design (PSCAD) is used to perform simulation research on an electric Power system, the simulation system uses a "T" connection high-voltage transmission line model with a voltage level of 220kV shown in fig. 5, M, N, P is a three-terminal Power supply, S is a measurement point of an M terminal, a T point is a line branch point, i.e., a wave impedance discontinuous point, an F point is a fault point, R is a transition resistance, a line has a single-phase ground fault, models and parameters of simulation lines (T connection high-voltage transmission line model) are respectively shown in table 1, and Power supply parameters of the simulation lines are shown in table 2.
Table 1 simulation line parameters
| Line | Line model | Line length (km) |
| LMT | GL/GIA-300/40 | 60 |
| LNT | GL/GIA-300/40 | 50 |
| LPT | GL/GIA-300/40 | 40 |
TABLE 2 Power supply parameters
| Power supply | Amplitude (kV) | Phase angle (°) |
| M | 220 | 0 |
| N | 220 | 30 |
| P | 220 | -30 |
A phase-to-ground fault occurs at a position 70km away from the end M of the line MN, and the transition resistance is 20 omega. The original traveling wave U of the three-phase voltage collected by the wave recording device 102 of the measuring point by taking the reclosing moment as the starting pointa、Ub、UcAs shown in fig. 6. The processor 104 performs fault phase selection on the three-phase voltage, determines a fault phase and a non-fault phase, and performs phase-mode conversion on the three-phase voltage to obtain a line-mode traveling wave including the fault phase and a line-mode traveling wave including the non-fault phase corresponding to the three-phase voltage traveling wave, as shown in fig. 7.
The line mode traveling wave containing fault phase and the line mode traveling wave formed by non-fault phase are respectively subjected to wavelet transformation by the following formula,
and the mode maximum value of the line mode traveling wave containing the fault phase and the line mode traveling wave composed of the non-fault phase after the wavelet transformation is calculated by the following formula, as shown in figure 9,
wherein f (n) represents data points of the line mode traveling wave containing the fault phase or the line mode traveling wave consisting of the non-fault phase, n is a sampling point,
representing the approximation component of the j-th scale,
wavelet components representing the j-th scale, h (k), g (k) representing filter parameters, j being the scale, k being the data point currently processed, and k being a positive integer, η being a construction coefficient,
modulus maximum, n, representing the wavelet transform of the j-th scalekRepresenting the kth point data in the current scale,
the wavelet component of the j-th scale representing the kth point data in the current scale.
Then, according to the following formula, normalizing the line mode traveling wave containing the fault phase and the line mode traveling wave composed of the non-fault phase, calculating the superimposed component of the reclosing line mode traveling wave at the fault point according to the normalized line mode traveling wave containing the fault phase and the line mode traveling wave composed of the non-fault phase, as shown in figure 8,
wherein, YαRepresenting line-mode travelling waves, M, containing faulted phasesαRepresenting the first modal maximum, Y, of a line-mode travelling wave containing a faulted phaseγLine mode travelling wave, M, representing the constitution of a non-faulted phaseγHead of line mode travelling wave representing non-fault phase constitutionThe maximum of the individual modes,
represents the normalized line mode traveling wave containing the fault phase,
and expressing the line mode travelling wave formed by the normalized non-fault phase.
Calculating the superposed component of the reclosing line mode travelling wave at the fault point by the following formula:
wherein the content of the first and second substances,
showing the superimposed components of the reclosing line mode travelling wave at the fault point,
represents the normalized line mode traveling wave containing the fault phase,
and expressing the line mode travelling wave formed by the normalized non-fault phase.
In addition, in order to facilitate the comparative examination of the fault amount, the wavelet transformation is performed on the superposed component of the reclosing line mode travelling wave at the fault point, as shown in fig. 10.
Finally the distance between the fault point and the measuring point is determined by the following formula,
where x denotes the distance between the fault point and the measurement point, t1Indicating the reclosing time, t2Showing the arrival time of the reflected wave at the first fault point, and v shows the arrival time of the reflected wave at the first fault pointLine mode wave velocity of phase voltage traveling waves or three-phase current traveling waves.
The distance measurement result obtained by the embodiment is 69.84km, the true value of the fault distance is 70km, the absolute error is 160m, the relative error is 0.2286%, the error of the fault distance measurement result is small, and the positioning is accurate.
In another embodiment of the present invention, to verify the performance of the ranging method, the fault ranging result is shown in table 3 for different locations and different transition resistances on the line MN.
TABLE 3 ranging results
The simulation experiment proves that the fault location system is not affected by the transition resistance, has high reliability, has the location error less than 0.5km, and can accurately and effectively determine the position of the fault point.
In the description herein, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance unless explicitly stated or limited otherwise; the terms "connected," "mounted," "secured," and the like are to be construed broadly and include, for example, fixed connections, removable connections, or integral connections; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the description herein, the description of the terms "one embodiment," "some embodiments," "specific embodiments," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. The utility model provides a fault location system of transmission line, is applicable to utilize reclosing travelling wave to carry out fault point location after transmission line single-phase fault takes place, its characterized in that includes:
the wave recording device is positioned at a measuring point of the power transmission line and is used for acquiring the reclosing three-phase voltage traveling wave or the three-phase current traveling wave;
the processor is connected with the wave recording device and used for constructing a line mode traveling wave containing a fault phase and a line mode traveling wave formed by a non-fault phase according to the three-phase voltage traveling wave or the three-phase current traveling wave; and
determining the superposition component of the reclosing line mode traveling wave at the fault point according to the line mode traveling wave containing the fault phase and the line mode traveling wave formed by the non-fault phase; and
determining the distance between the fault point and the measuring point according to the superposition component of the reclosing line mode traveling wave at the fault point and the reclosing time;
and the display device is connected with the processor and used for displaying the distance of the fault point of the power transmission line.
2. The fault location system of an electric transmission line of claim 1, further comprising:
the power supply is used for providing electric energy for a fault location system of the power transmission line;
the prompting device is connected with the processor and used for sending the distance between the fault point and the measuring point through a short message;
and the filtering device is connected with the processor and is used for carrying out noise reduction treatment on the line mode traveling wave containing the fault phase and the line mode traveling wave formed by the non-fault phase.
3. The system according to claim 1, wherein the processor is specifically configured to:
performing fault phase selection on the three-phase voltage traveling wave or the three-phase current traveling wave, and determining a fault phase and a non-fault phase of the power transmission line;
and carrying out phase-mode conversion processing on the three-phase voltage traveling wave or the three-phase current traveling wave according to the fault phase and the non-fault phase to obtain the line-mode traveling wave containing the fault phase and the line-mode traveling wave formed by the non-fault phase.
4. Fault ranging system of an electric transmission line according to claim 3,
and performing phase-mode conversion processing on the three-phase voltage traveling wave or the three-phase current traveling wave by adopting the following formula, taking the fault of the a phase to the ground as an example:
Yα＝Ua-Ubor Yα＝Ia-Ib
Yγ＝Ub-UcOr Yγ＝Ib-Ic
Wherein, the phase a is the fault phase, the phases b and c are the non-fault phases, YαRepresenting said line-mode travelling wave, Y, containing a faulty phaseγRepresenting line mode travelling waves, U, of said non-faulted phaseaRepresenting a travelling wave, U, of the phase voltage ab、UcRepresents a traveling wave of the voltages of b and c phases, IaRepresents a traveling wave of a-phase current, Ib、IcThe b-phase current traveling wave and the c-phase current traveling wave are shown, respectively.
5. The system according to claim 2, wherein the processor is further configured to:
respectively carrying out normalization processing on the line mode traveling wave containing the fault phase and the line mode traveling wave formed by the non-fault phase;
and determining the superposition component of the reclosing line mode traveling wave at the fault point according to the normalized line mode traveling wave containing the fault phase and the normalized line mode traveling wave formed by the non-fault phase.
6. Fault ranging system of an electric transmission line according to claim 5,
respectively carrying out normalization processing on the line mode traveling wave containing the fault phase and the line mode traveling wave formed by the non-fault phase by adopting the following formula:
wherein, YαRepresenting said line-mode travelling wave containing a faulty phase, MαRepresenting the first modal maximum, Y, of the line-mode travelling wave containing the faulted phaseγLine mode travelling wave, M, representing the composition of said non-faulted phaseγRepresenting the first modal maximum of the line-mode travelling wave formed by said non-faulted phase,
representing the normalized line mode travelling wave containing the fault phase,
and representing the normalized line mode travelling wave formed by the non-fault phase.
7. Fault ranging system of an electric transmission line according to claim 5,
determining the superposed component of the reclosing line mode travelling wave at the fault point by adopting the following formula:
wherein the content of the first and second substances,
showing the superimposed component of the reclosing line mode travelling wave at the fault point,
represents the normalized line mode traveling wave containing the fault phase,
and expressing the line mode travelling wave formed by the normalized non-fault phase.
8. The system of claim 5, wherein the processor is further configured to:
and respectively carrying out wavelet transformation on the line mode traveling wave containing the fault phase and the line mode traveling wave consisting of the non-fault phase to obtain a first modulus maximum value of the line mode traveling wave containing the fault phase and a first modulus maximum value of the line mode traveling wave consisting of the non-fault phase.
9. Fault ranging system of an electric transmission line according to claim 8,
and respectively carrying out wavelet transformation on the line mode traveling wave containing the fault phase and the line mode traveling wave consisting of the non-fault phase by adopting the following formula:
wherein f (n) represents data points of the line mode traveling wave containing the fault phase or the line mode traveling wave composed of the non-fault phase, n is a sampling point,
representing the approximation component of the j-th scale,
wavelet components representing the j-th scale, h (k), g (k) represent parameters of the filtering device, j is the scale, k is a data point currently processed, and eta is a construction coefficient;
determining the modulus maximum value after wavelet transformation by adopting the following formula:
wherein the content of the first and second substances,
modulus maximum, n, representing the wavelet transform of the j-th scalekRepresenting the kth point data in the current scale,
the wavelet component of the j-th scale representing the kth point data in the current scale.
10. Fault ranging system of a transmission line according to one of claims 1 to 9,
determining the distance between the fault point and the measurement point by using the following formula:
wherein x represents the distance between the fault point and the measurement point, t1Indicating the reclosing time, t2And v represents the line mode wave velocity of the voltage or current traveling wave.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1367392A (en) * | 2001-12-28 | 2002-09-04 | 清华大学 | High-accuracy failure wave-recording device and its transmission line combined failure distance-measuring method |
| CN101159376A (en) * | 2007-09-26 | 2008-04-09 | 东北大学 | Low current neutral grounding malfunction detection and positioning device and method |
| CN101299538A (en) * | 2008-04-08 | 2008-11-05 | 昆明理工大学 | Cable-aerial mixed line fault travelling wave ranging method |
| CN101776725A (en) * | 2010-01-13 | 2010-07-14 | 上海交通大学 | Fault positioning method for transmission line |
| CN101943738A (en) * | 2010-08-04 | 2011-01-12 | 清华大学 | Single-phase grounding distance measuring method and distance measuring device |
| CN106841913A (en) * | 2017-01-13 | 2017-06-13 | 清华大学 | Distribution line failure distance-finding method |
| CN106841914A (en) * | 2017-01-13 | 2017-06-13 | 清华大学 | The fault location device of distribution line |
| CN109001594A (en) * | 2018-07-26 | 2018-12-14 | 国网湖南省电力有限公司 | A kind of functional failure travelling wave positioning method |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104133156B (en) * | 2014-07-16 | 2017-01-18 | 山东大学 | Hybrid line single-ended traveling wave fault distance measuring method based on fault distance interval |
| WO2017049224A1 (en) * | 2015-09-18 | 2017-03-23 | Schweitzer Engineering Laboratories, Inc. | Time-domain line protection of electric power delivery systems |
| CN105866621A (en) * | 2016-03-30 | 2016-08-17 | 昆明理工大学 | Fault ranging method based on mode time difference |
| CN105738771B (en) * | 2016-04-01 | 2019-07-05 | 昆明理工大学 | A kind of one-end fault ranging method based on the route containing TCSC of distribution character along fault traveling wave |
-
2019
- 2019-08-22 CN CN201910779752.5A patent/CN110456226B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1367392A (en) * | 2001-12-28 | 2002-09-04 | 清华大学 | High-accuracy failure wave-recording device and its transmission line combined failure distance-measuring method |
| CN101159376A (en) * | 2007-09-26 | 2008-04-09 | 东北大学 | Low current neutral grounding malfunction detection and positioning device and method |
| CN101299538A (en) * | 2008-04-08 | 2008-11-05 | 昆明理工大学 | Cable-aerial mixed line fault travelling wave ranging method |
| CN101776725A (en) * | 2010-01-13 | 2010-07-14 | 上海交通大学 | Fault positioning method for transmission line |
| CN101943738A (en) * | 2010-08-04 | 2011-01-12 | 清华大学 | Single-phase grounding distance measuring method and distance measuring device |
| CN106841913A (en) * | 2017-01-13 | 2017-06-13 | 清华大学 | Distribution line failure distance-finding method |
| CN106841914A (en) * | 2017-01-13 | 2017-06-13 | 清华大学 | The fault location device of distribution line |
| CN109001594A (en) * | 2018-07-26 | 2018-12-14 | 国网湖南省电力有限公司 | A kind of functional failure travelling wave positioning method |
Non-Patent Citations (2)
| Title |
|---|
| Travelling waves-based fault location scheme;Shenxing Shi et.al;《IEEE Xplore Digital Library》;20181025;第1326-1329页 * |
| 电力系统行波测距方法探究;李玥桦 等;《电力与能源》;20180831;第39卷(第4期);第506-509页 * |
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