CN112345978A - Ground fault positioning method based on two-phase injection pulse at low-voltage side of distribution transformer - Google Patents
Ground fault positioning method based on two-phase injection pulse at low-voltage side of distribution transformer Download PDFInfo
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- G—PHYSICS
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- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
- G01R31/62—Testing of transformers
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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
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
- G01R31/52—Testing for short-circuits, leakage current or ground faults
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Abstract
The invention relates to a ground fault positioning method based on two-phase injection pulses at the low-voltage side of a distribution transformer, and belongs to the technical field of single-phase ground fault detection and positioning. The invention injects the same pulse signal from a certain two phases of the low-voltage side of the distribution transformer at the same time, and the injected pulse signal is coupled to the three phases of the high-voltage side and amplified by utilizing the electromagnetic transmission characteristic of the distribution transformer. The amplified pulse signal is transmitted on a line, and is refracted and reflected when meeting a fault point, and the fault signal is transmitted back to the distribution transformer and influences the three-phase waveform. And measuring signals of all phases at the high-voltage side of the distribution transformer through the discharge detection sensor, and completing the phase selection of the fault line according to the waveform characteristics of the detected signals of all phases. According to the time difference between the first pulse signal and the second pulse signal of the fault phase, the measurement of the fault distance can be realized, and thus the single-phase earth fault positioning is realized. The method shortens troubleshooting time, and effectively improves power supply reliability and intelligent level of the power grid.
Description
Technical Field
The invention belongs to the technical field of single-phase earth fault detection and positioning, and particularly relates to an earth fault positioning method based on two-phase injection pulses at the low-voltage side of a distribution transformer.
Background
The distribution network is used as the tail end of the power grid and directly reflects the requirements of users on the aspects of electric energy safety, high quality, economy and the like. With the continuous development of distribution networks in China, users put forward higher requirements on the reliability and the power supply quality of power supply, once a distribution network fails, the position where the failure occurs should be found out as soon as possible, isolation is adopted, and coping strategies are put forward to restore the power supply to the users. At present, a 10kV distribution network system mostly adopts a radial network, and the distribution network system has multiple branches and a complex structure and is easy to generate single-phase earth faults.
At present, the following problems mainly exist in the fault location of the power distribution network: firstly, the accuracy of fault judgment of the small-current grounding line selection device is not high; and secondly, because the configuration of the fault indicator is not scientific, the power supply of a power supply is not stable, the remote transmission mode is not reliable, when the fault is positioned and isolated by using the reclosing breaker and the fault indicator, the device frequently makes erroneous judgment and refusal operation, and the actual effect is not obvious. In a distribution network system, the single-phase earth fault accounts for more than 70% of the total number of the distribution network faults, and the problem of how to improve the fault positioning accuracy needs to be solved urgently.
Disclosure of Invention
The invention aims to solve the defects of the prior art, and provides a ground fault positioning method based on two-phase injection pulses at the low-voltage side of a distribution transformer.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
the ground fault positioning method based on the two-phase injection pulse at the low-voltage side of the distribution transformer comprises the following steps:
step (1), connecting signal generating devices at the low-voltage sides of the phase A and the phase B of the distribution transformer;
step (2), selecting all outgoing lines on the high-voltage side of the distribution transformer, and connecting all phases to a discharge detection sensor;
step (3), when the signal generating device injects voltage with the amplitude value of A phase and B phase of the distribution transformer to be the sameU 0The pulse signal of (3);
step (4), a discharge detection sensor detects a voltage signal of the high-voltage side of the distribution transformer; then transmitting the acquired signal to a fault positioning device;
step (5), analyzing the signals detected by the discharge detection sensors by the fault positioning device to obtain pulse signals detected by the discharge detection sensors of all phases;
step (6), if the phase B has no pulse, judging that the fault is the phase B, and performing step (7); otherwise, judging that the fault is in the phase A and the phase C, and jumping to the step (9);
step (7), connecting the signal generating device to the low-voltage sides of the A phase and the C phase, and simultaneously injecting the signal with the amplitude ofU 0The pulse signal of (3);
step (8), after repeating step (4) and step (5), performing step (9);
step (9), if the product of the peak value of the first pulse of the phase A and the peak value of the second pulse is negative, the phase A is judged to be a fault phase, otherwise, the phase C is judged to be a fault phase;
step (10), reading the detected fault phase signal characteristics, and recording the time corresponding to the first pulse amplitude and the second pulse amplitude as the time respectivelyt 1Andt 2and positioning is carried out by utilizing the time difference.
Further, it is preferable that the distribution transformer is coupled with Dyn 11.
Further, it is preferable that the second pulse is discriminated as follows:
if the line has no branch, directly judging according to the waveform;
if the line has one or more branches and the branch point reflection waveform will cause interference, the following calculation is needed:
when the A phase or the C phase is judged to be in fault, multiplying the waveform of the A phase or the C phase by a coefficient-1, and recording as A 'and C'; then judging the part where A 'and C' are not coincident, wherein the time period corresponding to the first non-coincident part is the time period corresponding to the second pulse of the fault phase, and judging the pulse on the fault phase in the time period to be the second pulse;
when the B-phase fault is judged, multiplying the B-phase or C-phase waveform by a coefficient-1, and recording as B 'and C'; and then judging the part where the B 'and the C' are not coincident, wherein the time period corresponding to the first non-coincident part is the time period corresponding to the second pulse of the fault phase, and judging the pulse on the fault phase in the time period to be the second pulse.
Further, preferably, the signal transmission module and the fault location device are transmitted in a wireless or wired transmission mode.
Further, it is preferable that, if the line is not branched, the line is directly positioned according to the time difference between the first pulse and the second pulse; if the line has one or more branches, determining a fault branch according to a removing method;
the elimination method utilizes the time difference between the amplitudes of the second pulse and the third pulse to calculate the length of the overhead line as the length of a side branch with a common fulcrum with a branch where a fault point is located; and according to the characteristic of the length of the side branch, excluding other lines with the same length as the length calculated by the time difference of the first pulse amplitude and the second pulse amplitude.
The absence of pulses in the present invention generally means: 1/2 with amplitudes less than the amplitudes of the pulses in the other same time periods are considered pulse-free.
In the invention, the first pulse is the first pulse of the signal of the detected fault phase, namely the signal coupled to the high-voltage side after the low-voltage side is injected. The second pulse is a signal reflected by a fault point after traveling waves on a fault phase meet a single-phase ground fault.
The invention injects the same pulse signal from a certain two phases at the same time at the low-voltage side of the Dyn11 distribution transformer, and the injected pulse signal is coupled to the three phases at the high-voltage side and amplified by utilizing the electromagnetic transmission characteristic of the distribution transformer. The amplified pulse signal is transmitted on a line, and is refracted and reflected when meeting a fault point, and the fault signal is transmitted back to the distribution transformer and influences the three-phase waveform. The discharge detection sensor is used for measuring signals of all phases at the high-voltage side of the distribution transformer, and the phase selection of a fault line can be completed according to the waveform characteristics of the detected signals of all phases. According to the time difference between the first pulse signal and the second pulse signal of the fault phase, the measurement of the fault distance can be realized, and thus the single-phase earth fault positioning is realized.
Compared with the prior art, the invention has the beneficial effects that:
the invention is based on the electromagnetic transmission characteristic of a Dyn11 distribution transformer, and pulse signals are injected from a certain two phases of a low-voltage side and coupled to a high-voltage side, so that the signals can be amplified to improve the signal detectability, and the fault phase selection can be carried out by utilizing the waveform characteristics of the signals of the high-voltage side. And after phase selection, the fault distance is calculated and calculated by taking the time difference of the pulse signals detected by the high-voltage side fault phase as a basis, and manual distance measurement is not involved. In the conventional injection method, pulse signals are directly injected into a line, and a high-voltage power supply which is large in size and inconvenient to carry needs to be designed. The invention has the advantages of less equipment required in the line selection and ranging process and simple steps, greatly lightens the burden of operation and maintenance personnel, shortens troubleshooting time, and effectively improves the power supply reliability and the intelligent level of a power grid.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
Fig. 1 is a schematic diagram of a wiring structure in the method for positioning a ground fault based on two-phase injection pulses at the low-voltage side of a distribution transformer according to the present invention;
FIG. 2 is a flow chart of the ground fault location based on two-phase injection pulses at the low-voltage side of the distribution transformer according to the present invention;
FIG. 3 is a simulation schematic diagram of single-phase earth fault location of a 10kV distribution overhead line system;
fig. 4 is a simulation result diagram.
Detailed Description
The present invention will be described in further detail with reference to examples.
It will be appreciated by those skilled in the art that the following examples are illustrative of the invention only and should not be taken as limiting the scope of the invention. The examples do not specify particular techniques or conditions, and are performed according to the techniques or conditions described in the literature in the art or according to the product specifications. The materials or equipment used are not indicated by manufacturers, and all are conventional products available by purchase.
It will be appreciated by those skilled in the art that the following examples are illustrative of the invention only and should not be taken as limiting the scope of the invention. The examples do not specify particular techniques or conditions, and are performed according to the techniques or conditions described in the literature in the art or according to the product specifications. The materials or equipment used are not indicated by manufacturers, and all are conventional products available by purchase.
As used herein, the singular forms "a", "an", "the" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It will be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. Further, "connected" as used herein may include wirelessly connected. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
In the description of the present invention, "a plurality" means two or more unless otherwise specified. The terms "inner," "upper," "lower," and the like, refer to an orientation or a state relationship based on that shown in the drawings, which is for convenience in describing and simplifying the description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the invention.
In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "provided" are to be construed broadly, e.g., as being fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. To those of ordinary skill in the art, the specific meanings of the above terms in the present invention are understood according to specific situations.
It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
As shown in fig. 1-2, the method for positioning a ground fault based on two-phase injection pulses at a low-voltage side of a distribution transformer includes the following steps:
the low-voltage sides of the A phase and the B phase of the Dyn11 type distribution transformer at the position 1 are connected with the signal generating device, and the position of the injection end of the signal generating device is marked as 2;
selecting all outgoing lines on the high-voltage side of the distribution transformer, and connecting all phases to a discharge detection sensor, wherein the position of the discharge detection sensor is marked as 3;
when the signal generating device injects voltage with the amplitude value of being equal to that of the A phase and the B phase of the distribution transformerU 0The pulse signal of (3);
a discharge detection sensor at the position 3 detects a voltage signal at the high-voltage side of the distribution transformer; then transmitting the acquired signal to a fault positioning device at a position 4;
the fault positioning device analyzes signals detected by the discharge detection sensors to obtain pulse signals detected by the discharge detection sensors of all phases;
judging whether the phase B has a pulse (1/2 with the amplitude smaller than that of other pulses in the same period is regarded as no pulse); specifically, the pulse voltage signal is acquired by a discharge detection sensor installed on the high-voltage side of the transformer;
if the phase B has no pulse (the amplitude is smaller than 1/2 of pulse amplitudes in other same time periods, the phase B is judged to be a fault phase, otherwise, the phase A or the phase C is judged to be a fault phase;
if phase B is a fault phase, the low voltage side A, C of the transformer is connected in parallel, and the injection amplitude isU 0The pulse voltage signal of (2). Specifically, the low voltage side A, C of the distribution transformer is connected in parallel and connected to the signal generating device at position 1, and the amplitude value is injected by the signal generating deviceU 0The pulse voltage signal of (a);
and if the A phase or the C phase is the fault phase, multiplying the peak value of the first pulse peak and the second pulse peak of the A phase. Specifically, the first pulse is a first pulse of a signal of a detected fault phase, that is, a signal which is injected from a low-voltage side and then coupled to a high-voltage side, and the second pulse is a signal which is reflected by a fault point after a traveling wave on the fault phase meets a single-phase ground fault; the second pulse discrimination method is as follows: multiplying the waveform of the phase A or the phase C by a coefficient-1, and recording the waveform as A 'and C'; then judging the part where A 'and C' are not coincident, wherein the time period corresponding to the first non-coincident part is the time period corresponding to the second pulse of the fault phase, and judging the pulse on the fault phase in the time period to be the second pulse;
if the phase A or the phase C is a fault phase and the product of the peak value of the first pulse peak and the peak value of the second pulse peak of the phase A is negative, judging the phase A fault, otherwise, judging the phase C fault;
and finally reading the signal characteristics of the fault phase after the fault phase is judged to be completed, and positioning by utilizing the time difference. Specifically, when the A phase or the C phase is judged to be in fault, multiplying the waveform of the A phase or the C phase by a coefficient-1, and recording as A 'and C'; then judging the part where A 'and C' are not coincident, wherein the time period corresponding to the first non-coincident part is the time period corresponding to the second pulse of the fault phase, and judging the pulse on the fault phase in the time period to be the second pulse; when the B-phase fault is judged, multiplying the B-phase or C-phase waveform by a coefficient-1, and recording as B 'and C'; then judging the part where B 'and C' are not coincident, wherein the time period corresponding to the first non-coincident part is the time period corresponding to the second pulse of the fault phase, and judging the pulse on the fault phase in the time period to be the second pulse; the time corresponding to the first pulse amplitude and the second pulse amplitude are respectively recorded ast 1Andt 2(ii) a If the line is simple and has no branch, the positioning can be directly carried out according to the time difference between the first pulse and the second pulse; if the line is complex and has one or more branches, determining the fault branch according to a removing method; specifically, the elimination method uses the time difference between the amplitude of the second pulse and the amplitude of the third pulse, and the third pulse judgment method is the same as the second pulse, except that the third pulse is the 2 nd non-coincident pulse in the non-coincident part of A 'and C' (B 'and C' when judging that the B phase fails); the length of the overhead line obtained by calculating the time difference between the amplitudes of the second pulse and the third pulse is the length of a side branch with a common fulcrum in the branch where the fault point is located; according to the characteristic of the length of the side branch, other lines with the same length as the length calculated by the time difference of the first pulse amplitude and the second pulse amplitude can be excluded.
The specific calculation formula for positioning by using the time difference is as follows:
wherein,Lthe distance between the line fault point and the distribution transformer is calculated, and c is the light speed value of 3 multiplied by 108m/s, first pulse amplitude and second pulse amplitudeThe value corresponds to a time oft 1Andt 2。
simulation example:
the simulation of single-phase earth fault location in a 10kV distribution overhead line system by using the method provided by the invention is shown in figure 3. Wherein, a rectangular signal simulation circuit with the amplitude of 400V is selected as a voltage source and corresponds to a signal generating device at the position 2 in practice; distribution transformer P _ transf corresponds to the Dyn11 distribution transformer at position 1 in practice; TLine _1 with the length of 5km is connected to the high-voltage side of a distribution transformer P _ transf, and then is divided into two lines: TLine _2 with the length of 100km and TLine _3 with the length of 3.5km, wherein a single-phase ground fault (grounded through a 1-ohm resistor in the figure) which is 2km away from a branch point on the TLine _2 divides the TLine _2 into TLine _11 and TLine _12, and a C-phase fault is simulated in simulation; voltage to ground measured by high-voltage side of distribution transformer in simulationE A、E BAndE Cand respectively correspond to the voltage signals of the high-voltage side of the distribution transformer detected by the discharge detection sensor at the actual middle position 3. The low voltage side A, B of the distribution transformer P _ transf is connected in parallel to a voltage source represented by a rectangular signal simulation circuit, and the simulation result is shown in fig. 4.
According to the simulation result and the single-phase earth fault positioning method based on the injection of the pulse signal at the low-voltage side of the distribution transformer: if the pulse exists in the phase B, judging that the fault is in the phase A or the phase C, and jumping to the step (9); determining a first pulse and a second pulse (marked in figure 4) according to a discrimination method of the first pulse and the second pulse, reading a peak value of the first pulse of the phase A and a peak value of the second pulse, judging a product, judging that the phase C is a fault phase if the product is not negative; step (10) is carried out, signal characteristics of the fault phase C phase are read, and the corresponding time of the first pulse amplitude and the second pulse amplitude is t1=11.04 μ s and t2=57.61 μ s, substituting the time difference positioning calculation formula to calculate L =6.985km, and the error is 0.015 km; the method further comprises the steps of determining a fault branch according to a removing method and judging a third pulse to read information according to a judging method of the third pulse because a line is complex and has branches, wherein the time corresponding to the amplitude of the third pulse is t3=82.07 μ s; the second pulseThe length of the side branch obtained by calculating the time difference between the amplitudes of the third pulse and the third pulse is L' =3.669km, and is close to the actual length of TLine _3, so that the TLine _3 is judged to be the side branch, and the fault is on TLine _ 2. Finally, a fault point which is 0.015km away from the transformer 6.985km on TLine _2 is determined.
As can be seen from the example, the fault positioning effect obtained by the method provided by the invention is good, and the error is small. And a larger detectable fault voltage signal can be obtained by using a smaller pulse injection voltage, so that the problem that a heavy and inconvenient high-voltage power supply needs to be carried when the traditional injection method is used for positioning can be solved. According to the method, the ground fault signal is easy to identify and judge, and a complex algorithm does not need to be designed.
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (5)
1. The ground fault positioning method based on the two-phase injection pulse at the low-voltage side of the distribution transformer is characterized by comprising the following steps of:
step (1), connecting signal generating devices at the low-voltage sides of the phase A and the phase B of the distribution transformer;
step (2), selecting all outgoing lines on the high-voltage side of the distribution transformer, and connecting all phases to a discharge detection sensor;
step (3), when the signal generating device injects voltage with the amplitude value of A phase and B phase of the distribution transformer to be the sameU 0The pulse signal of (3);
step (4), a discharge detection sensor detects a voltage signal of the high-voltage side of the distribution transformer; then transmitting the acquired signal to a fault positioning device;
step (5), analyzing the signals detected by the discharge detection sensors by the fault positioning device to obtain pulse signals detected by the discharge detection sensors of all phases;
step (6), if the phase B has no pulse, judging that the fault is the phase B, and performing step (7); otherwise, judging that the fault is in the phase A and the phase C, and jumping to the step (9);
step (7), connecting the signal generating device to the low-voltage sides of the A phase and the C phase, and simultaneously injecting the signal with the amplitude ofU 0The pulse signal of (3);
step (8), after repeating step (4) and step (5), performing step (9);
step (9), if the product of the peak value of the first pulse of the phase A and the peak value of the second pulse is negative, the phase A is judged to be a fault phase, otherwise, the phase C is judged to be a fault phase;
step (10), reading the detected fault phase signal characteristics, and recording the time corresponding to the first pulse amplitude and the second pulse amplitude as the time respectivelyt 1Andt 2and positioning is carried out by utilizing the time difference.
2. The method of claim 1 wherein the distribution transformer is coupled using Dyn 11.
3. The method for locating a ground fault based on two-phase injection pulse at the low-voltage side of a distribution transformer according to claim 1, wherein the second pulse is determined by the following method:
if the line has no branch, directly judging according to the waveform;
if the line has one or more branches and the branch point reflection waveform will cause interference, the following calculation is needed:
when the A phase or the C phase is judged to be in fault, multiplying the waveform of the A phase or the C phase by a coefficient-1, and recording as A 'and C'; then judging the part where A 'and C' are not coincident, wherein the time period corresponding to the first non-coincident part is the time period corresponding to the second pulse of the fault phase, and judging the pulse on the fault phase in the time period to be the second pulse;
when the B-phase fault is judged, multiplying the B-phase or C-phase waveform by a coefficient-1, and recording as B 'and C'; and then judging the part where the B 'and the C' are not coincident, wherein the time period corresponding to the first non-coincident part is the time period corresponding to the second pulse of the fault phase, and judging the pulse on the fault phase in the time period to be the second pulse.
4. The method for locating the ground fault based on the two-phase injection pulse at the low-voltage side of the distribution transformer according to claim 1, wherein the signal transmission module and the fault locating device are transmitted in a wireless or wired transmission mode.
5. The method for locating the ground fault based on the two-phase injection pulse on the low-voltage side of the distribution transformer according to claim 1, wherein if the line is not branched, the line is directly located according to the time difference between the first pulse and the second pulse; if the line has one or more branches, determining a fault branch according to a removing method;
the elimination method utilizes the time difference between the amplitudes of the second pulse and the third pulse to calculate the length of the overhead line as the length of a side branch with a common fulcrum with a branch where a fault point is located; and according to the characteristic of the length of the side branch, excluding other lines with the same length as the length calculated by the time difference of the first pulse amplitude and the second pulse amplitude.
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| WO2023221432A1 (en) * | 2022-05-17 | 2023-11-23 | 云南电网有限责任公司临沧供电局 | Fault finding system and method for three-phase circuit |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0670448A (en) * | 1991-03-07 | 1994-03-11 | Shikoku Sogo Kenkyusho:Kk | Method of detecting grounded phase and grounded feeder |
| JP2001199335A (en) * | 2000-01-17 | 2001-07-24 | East Japan Railway Co | Configuration of ground probe with telegram checking function |
| CN101067928A (en) * | 2007-07-10 | 2007-11-07 | 章森 | A new method for measuring sound wave-form similarity |
| CN103176103A (en) * | 2013-03-15 | 2013-06-26 | 华北电力大学 | Overhead power distribution line single-phase grounding fault positioning method |
| CN203811739U (en) * | 2014-04-22 | 2014-09-03 | 北京水木源华电气股份有限公司 | Phase-to-ground fault detection apparatus |
| CN105425109A (en) * | 2015-11-27 | 2016-03-23 | 天津大学 | Single-phase ground line selection method with function of accuracy improvement for small-current grounding system |
| RU2017100844A (en) * | 2017-01-10 | 2018-07-13 | Федеральное государственное бюджетное образовательное учреждение высшего образования "Вятский государственный университет" (ВятГУ) | METHOD FOR DETERMINING THE SINGLE-PHASE LOCATION ON THE GROUND IN A BRANCHED AIR POWER LINE WITH ISOLATED NEUTRAL |
| CN109167746A (en) * | 2018-08-31 | 2019-01-08 | 西南电子技术研究所（中国电子科技集团公司第十研究所） | Continuous wave and the quick identification device of pulse signal |
| 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 |
-
2020
- 2020-10-27 CN CN202011166199.7A patent/CN112345978B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0670448A (en) * | 1991-03-07 | 1994-03-11 | Shikoku Sogo Kenkyusho:Kk | Method of detecting grounded phase and grounded feeder |
| JP2001199335A (en) * | 2000-01-17 | 2001-07-24 | East Japan Railway Co | Configuration of ground probe with telegram checking function |
| CN101067928A (en) * | 2007-07-10 | 2007-11-07 | 章森 | A new method for measuring sound wave-form similarity |
| CN103176103A (en) * | 2013-03-15 | 2013-06-26 | 华北电力大学 | Overhead power distribution line single-phase grounding fault positioning method |
| CN203811739U (en) * | 2014-04-22 | 2014-09-03 | 北京水木源华电气股份有限公司 | Phase-to-ground fault detection apparatus |
| CN105425109A (en) * | 2015-11-27 | 2016-03-23 | 天津大学 | Single-phase ground line selection method with function of accuracy improvement for small-current grounding system |
| RU2017100844A (en) * | 2017-01-10 | 2018-07-13 | Федеральное государственное бюджетное образовательное учреждение высшего образования "Вятский государственный университет" (ВятГУ) | METHOD FOR DETERMINING THE SINGLE-PHASE LOCATION ON THE GROUND IN A BRANCHED AIR POWER LINE WITH ISOLATED NEUTRAL |
| CN109167746A (en) * | 2018-08-31 | 2019-01-08 | 西南电子技术研究所（中国电子科技集团公司第十研究所） | Continuous wave and the quick identification device of pulse signal |
| 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 (3)
| Title |
|---|
| MUHAMMAD BUDI RAHAYU WIDODO, ET AL.: "Analysis of Fault Location on Distribution System Using Impulse Injection learned by ANFIS", 2020 INTERNATIONAL SEMINAR ON INTELLIGENT TECHNOLOGY AND ITS APPLICATIONS (ISITIA), pages 38 - 43 * |
| 刘红文 等: "高精度配网单相接地故障检测与定位系统研发", 电气技术, no. 1, pages 60 - 66 * |
| 张健 等: "配电线路末端行波检测新方法", 电力科学与技术学报, vol. 31, no. 31, pages 81 - 87 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2023221432A1 (en) * | 2022-05-17 | 2023-11-23 | 云南电网有限责任公司临沧供电局 | Fault finding system and method for three-phase circuit |
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