CN112285487A - Method for determining section of ground fault of power distribution network - Google Patents
Method for determining section of ground fault of power distribution network Download PDFInfo
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- CN112285487A CN112285487A CN202011126654.0A CN202011126654A CN112285487A CN 112285487 A CN112285487 A CN 112285487A CN 202011126654 A CN202011126654 A CN 202011126654A CN 112285487 A CN112285487 A CN 112285487A
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- 238000000034 method Methods 0.000 title claims abstract description 19
- 238000002347 injection Methods 0.000 claims description 15
- 239000007924 injection Substances 0.000 claims description 15
- 238000004458 analytical method Methods 0.000 claims description 3
- 230000001131 transforming effect Effects 0.000 claims description 3
- 230000005674 electromagnetic induction Effects 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 4
- 230000007423 decrease Effects 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
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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
- G01R31/081—Locating faults in cables, transmission lines, or networks according to type of conductors
- G01R31/086—Locating faults in cables, transmission lines, or networks according to type of conductors in power transmission or distribution networks, i.e. with interconnected conductors
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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
- G01R31/11—Locating faults in cables, transmission lines, or networks using pulse reflection methods
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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
- 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
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Abstract
The invention relates to a method for determining the fault section of a power distribution network, which comprises the steps of analyzing a line before a fault occurs, obtaining the time of a first reflected wave of each node, injecting pulse signals into a fault phase and a non-fault phase at the low-voltage side of a distribution transformer respectively after the fault occurs, transmitting the pulse signals to a high-voltage side through electromagnetic induction of distribution transformer, transmitting the pulse signals into the line, and collecting traveling wave signals on the fault phase and the non-fault phase at the high-voltage side. After the signals acquired twice are compared, the first different point is caused by that the reflected wave generated after the injected traveling wave is transmitted to the fault point returns to the acquisition point, and the time of the point is located between two nodes, namely a fault generation section. The method provided by the invention is used for obtaining the fault section by injecting the signal at the low-voltage side of the distribution transformer and analyzing the obtained signal, and provides a new method for quickly finding out the fault area after the fault occurs.
Description
Technical Field
The invention relates to the field of power systems, in particular to a power distribution network fault section determining method.
Background
A10 kV power distribution network in China generally operates in a neutral point indirect grounding mode, and after a single-phase grounding fault accounting for 50% -80% of total faults occurs, a traditional processing method searches fault points through manual line patrol, and wastes time and labor. The accurate and effective single-phase earth fault positioning method is researched, and the method has important significance for improving the power supply reliability of the power distribution network and reducing the power failure loss.
In the class C traveling wave method proposed for eliminating the ground fault, a pulse signal is injected into the power system on the high-voltage side in an off-line state, and a fault distance is calculated by identifying a fault point reflected wave. However, after the failure distance is calculated, an accurate failure location cannot be obtained. This is because the distribution network has many branches, and there is often more than one location corresponding to the fault distance, and it is difficult to infer the fault location by knowing the fault distance.
Disclosure of Invention
In order to solve the above problems, the present invention provides a method for determining the section of a power distribution network ground fault, which uses the most common distribution transformer in the power distribution network to inject signals at the low-voltage side of the distribution transformer, and obtains the fault section by comparing the difference of the signals obtained from the non-fault phase and the fault phase.
In order to achieve the purpose, the invention provides the following technical scheme:
a power distribution network ground fault segmentation method comprises the following steps:
step (1), when a line has a fault, acquiring a traveling wave signal at a corresponding fault phase at a high-voltage side after injecting a pulse into the fault phase at a low-voltage side of a distribution transformer;
after a line has a fault, injecting a pulse into a non-fault phase at a low-voltage side of the distribution transformer, and acquiring a traveling wave signal at a corresponding non-fault phase at a high-voltage side;
subtracting the traveling wave signals obtained in the steps (1) and (2) to obtain difference data; finding out a first difference point, namely the point where the reflected wave of the fault point is located;
and (4) finding out a first reflected signal of each node on the line according to the line structure, wherein the first reflected wave of the node behind the fault point is influenced by the fault point, and further determining the specific position of the fault point.
Further, the step (3) is performed according to the following formula:
Δu＝u1-u2；
wherein, u1 is when the line breaks down, collect the travelling wave signal at the high-pressure side corresponding fault phase after distributing and transforming the low-pressure side fault phase injection pulse; u2 is that after a line has a fault, a traveling wave signal is collected at a high-voltage side corresponding to a non-fault phase after a pulse is injected into the non-fault phase at the low-voltage side of the distribution transformer. After the injection phase and the non-injection phase are respectively injected after the fault, the signals of the injection phase and the non-injection phase corresponding to the high-voltage side are subtracted, so that the influence of branches before the fault point and the like can be eliminated.
Further, the first reflected wave of each pivot point is marked on the fault phase traveling wave through the known line structure analysis.
Compared with the prior art, the invention has the following advantages and beneficial effects:
1. according to the invention, the signal is injected at the low-voltage side of the distribution transformer, so that the safety is improved compared with the conventional high-voltage side injection;
2. the invention marks the signals of the fault phase and the non-fault phase by analyzing the line structure to obtain the fault section, thereby supplementing the defect that fault distance measurement is not enough for positioning.
Drawings
FIG. 1 is a fault staging flow chart;
FIG. 2 is a schematic diagram of non-fault phase pulse signal injection;
FIG. 3 is a schematic diagram of the injection of the pulse signal of the fault phase with the fault point in the B branch;
FIG. 4 is a schematic diagram of the injection of the pulse signal in the D-branch fault phase with the fault point at;
FIG. 5 is a schematic diagram of a fault phase pulse signal injection with a fault point at a CE section;
FIG. 6 is a plot of the fault phase and non-fault phase voltage reflected signal signatures after pulse injection for the first embodiment;
FIG. 7 is a plot of the fault phase and non-fault phase voltage reflected signal signatures after pulse injection for the second embodiment;
fig. 8 is a plot of the fault phase and non-fault phase voltage reflected signals after pulse injection for the third embodiment.
Detailed Description
The technical solutions in the embodiments will be described clearly and completely with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the examples without making any creative effort, shall fall within the protection scope of the present invention.
Unless otherwise defined, technical or scientific terms used in the embodiments of the present application should have the ordinary meaning as understood by those having ordinary skill in the art. The use of "first," "second," and similar terms in the present embodiments does not denote any order, quantity, or importance, but rather the terms are used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. "mounted," "connected," and "coupled" are to be construed broadly and may, for example, be fixedly coupled, detachably coupled, or integrally coupled; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. "Upper," "lower," "left," "right," "lateral," "vertical," and the like are used solely in relation to the orientation of the components in the figures, and these directional terms are relative terms that are used for descriptive and clarity purposes and that can vary accordingly depending on the orientation in which the components in the figures are placed.
Example 1
As shown in fig. 1, the method for determining the segment of the ground fault of the power distribution network of the embodiment includes the following steps:
step (1), when a line has a fault, acquiring a traveling wave signal at a corresponding fault phase at a high-voltage side after injecting a pulse into the fault phase at a low-voltage side of a distribution transformer;
after a line has a fault, injecting a pulse into a non-fault phase at a low-voltage side of the distribution transformer, and acquiring a traveling wave signal at a corresponding non-fault phase at a high-voltage side;
subtracting the traveling wave signals obtained in the steps (1) and (2) to obtain difference data; the method is carried out according to the following formula:
Δu＝u1-u2；
wherein, u1 is when the line breaks down, collect the travelling wave signal at the high-pressure side corresponding fault phase after distributing and transforming the low-pressure side fault phase injection pulse; u2 is that after a line has a fault, a traveling wave signal is collected at a high-voltage side corresponding to a non-fault phase after a pulse is injected into the non-fault phase at the low-voltage side of the distribution transformer. Finding out a first difference point, namely the point where the reflected wave of the fault point is located;
and (4) finding out a first reflected signal of each node on the line according to the line structure, wherein the first reflected wave of the node behind the fault point is influenced by the fault point, and further determining the specific position of the fault point. The first reflected wave of each pivot point is marked on the fault phase traveling wave through the known line structure analysis.
As shown in fig. 2, after a line fault occurs, a traveling wave signal is collected at the high-voltage side corresponding to a non-fault phase after a pulse is injected into the non-fault phase at the low-voltage side of the distribution transformer. Only branch point reflected signals are included in the traveling wave signal.
As shown in fig. 3, when a line fails, a traveling wave signal is collected at the high-voltage side corresponding to the failed phase after a pulse is injected into the low-voltage side failed phase. The traveling wave signal includes a branch point reflection signal and a fault point reflection signal.
And comparing the obtained traveling wave signals to find out a first difference point, namely the point where the reflected wave of the fault point is located.
In fig. 3, a, b, and c represent the distribution transformer low-voltage side (phase rated voltage 400V), and the high-voltage side rated voltage 10 kV. The line lengths are respectively 3 km, 5 km, 7 km and 8km, wherein a point A is a line branch point 8km away from a distribution transformer, a point B is a distribution network branch tail end 10km away from the point A, a point C is a distribution line branch point, a point D is a line branch tail end, and a point E is a branch tail end. The sensor is placed at the outlet of the high-pressure side of the distribution transformer.
The acquired waveforms are as shown in fig. 6, and the first reflected signal of each node on the line is found out according to the line structure, and only the first reflected wave of the node behind the fault point is affected according to the fault point. The fault point reflection signal is after the first reflection at point C and the point B reflection signal decreases, indicating that the fault point is on the B branch.
Example 2
The method for determining the section of the power distribution network ground fault is the same as that in the embodiment 1.
As shown in fig. 2, after a line fault occurs, a traveling wave signal is collected at the high-voltage side corresponding to a non-fault phase after a pulse is injected into the non-fault phase at the low-voltage side of the distribution transformer. Only branch point reflected signals are included in the traveling wave signal.
As shown in fig. 4, when a line fails, a traveling wave signal is collected at the high-voltage side corresponding to the failed phase after a pulse is injected into the low-voltage side failed phase. The traveling wave signal includes a branch point reflection signal and a fault point reflection signal.
And comparing the obtained traveling wave signals to find out a first difference point, namely the point where the reflected wave of the fault point is located.
The collected waveforms are as shown in fig. 7, and the first reflected signal of each node on the line is found out according to the line structure, and only the first reflected wave of the node behind the fault point is affected according to the fault point. The fault point reflection signal is after the first reflection at point C and the D point reflection signal decreases, indicating that the fault point is on the D branch.
Example 3
The method for determining the section of the power distribution network ground fault is the same as that in the embodiment 1.
As shown in fig. 2, after a line fault occurs, a traveling wave signal is collected at the high-voltage side corresponding to a non-fault phase after a pulse is injected into the non-fault phase at the low-voltage side of the distribution transformer. Only branch point reflected signals are included in the traveling wave signal.
As shown in fig. 5, when a line fails, a traveling wave signal is collected at the high-voltage side corresponding to the failed phase after a pulse is injected into the low-voltage side failed phase. The traveling wave signal includes a branch point reflection signal and a fault point reflection signal.
And comparing the obtained traveling wave signals to find out a first difference point, namely the point where the reflected wave of the fault point is located.
The acquired waveforms are as shown in fig. 8, and the first reflected signal of each node on the line is found out according to the line structure, and only the first reflected wave of the node behind the fault point is affected according to the fault point. The fault point reflection signal is after the first reflection at point C and the E point reflection signal decreases, indicating that the fault point is between CEs.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (3)
1. A method for determining the section of the earth fault of a power distribution network is characterized by comprising the following steps: the method comprises the following steps:
step (1), when a line has a fault, acquiring a traveling wave signal at a corresponding fault phase at a high-voltage side after injecting a pulse into the fault phase at a low-voltage side of a distribution transformer;
after a line has a fault, injecting a pulse into a non-fault phase at a low-voltage side of the distribution transformer, and acquiring a traveling wave signal at a corresponding non-fault phase at a high-voltage side;
subtracting the traveling wave signals obtained in the steps (1) and (2) to obtain difference data; finding out a first difference point, namely the point where the reflected wave of the fault point is located;
and (4) finding out a first reflected signal of each node on the line according to the line structure, wherein the first reflected wave of the node behind the fault point is influenced by the fault point, and further determining the specific position of the fault point.
2. The method of claim 1, wherein: the step (3) is carried out according to the following formula:
wherein, u1 is when the line breaks down, collect the travelling wave signal at the high-pressure side corresponding fault phase after distributing and transforming the low-pressure side fault phase injection pulse; u2 is that after a line has a fault, a traveling wave signal is collected at a high-voltage side corresponding to a non-fault phase after a pulse is injected into the non-fault phase at the low-voltage side of the distribution transformer.
3. The method of claim 1, wherein: the first reflected wave of each pivot point is marked on the fault phase traveling wave through the known line structure analysis.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103926511A (en) * | 2014-03-17 | 2014-07-16 | 四川大学 | Distance measurement method for power distribution network ground fault based on zero-mode travelling wave difference |
| CN104880648A (en) * | 2015-06-19 | 2015-09-02 | 四川大学 | Ranging method for overhead line power distribution network single-phase earth fault |
| CN108120899A (en) * | 2017-12-21 | 2018-06-05 | 国网宁夏电力公司中卫供电公司 | A kind of single-ended Section Location of one-phase earthing failure in electric distribution network |
| CN110161358A (en) * | 2019-04-30 | 2019-08-23 | 云南电网有限责任公司电力科学研究院 | A kind of Earth design method and device |
-
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- 2020-10-20 CN CN202011126654.0A patent/CN112285487A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103926511A (en) * | 2014-03-17 | 2014-07-16 | 四川大学 | Distance measurement method for power distribution network ground fault based on zero-mode travelling wave difference |
| CN104880648A (en) * | 2015-06-19 | 2015-09-02 | 四川大学 | Ranging method for overhead line power distribution network single-phase earth fault |
| CN108120899A (en) * | 2017-12-21 | 2018-06-05 | 国网宁夏电力公司中卫供电公司 | A kind of single-ended Section Location of one-phase earthing failure in electric distribution network |
| CN110161358A (en) * | 2019-04-30 | 2019-08-23 | 云南电网有限责任公司电力科学研究院 | A kind of Earth design method and device |
Non-Patent Citations (4)
| Title |
|---|
| 于盛楠 等: "基于C型行波法的配电网故障定位的实用研究", 继电器, vol. 35, no. 10, pages 1 * |
| 何晓 等: "消除零模波速影响的配电网单端行波故障测距算法", 电力***保护与控制, vol. 44, no. 23, pages 39 - 45 * |
| 杨鹏 等: "配电网单相接地故障C型行波定位研究", 电气时代, no. 03, pages 100 - 103 * |
| 田志刚: "C型行波法在配电网故障定位中的应用", 大众用电, vol. 27, no. 2, pages 2 - 4 * |
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