CN110609197A - Rapid detection device and method for ground fault - Google Patents
Rapid detection device and method for ground fault Download PDFInfo
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- CN110609197A CN110609197A CN201910841300.5A CN201910841300A CN110609197A CN 110609197 A CN110609197 A CN 110609197A CN 201910841300 A CN201910841300 A CN 201910841300A CN 110609197 A CN110609197 A CN 110609197A
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- 238000001514 detection method Methods 0.000 title claims abstract description 105
- 238000000034 method Methods 0.000 title claims abstract description 24
- 238000004891 communication Methods 0.000 claims abstract description 23
- 238000012545 processing Methods 0.000 claims abstract description 21
- 238000012360 testing method Methods 0.000 claims abstract description 8
- 238000012031 short term test Methods 0.000 claims 1
- 238000013024 troubleshooting Methods 0.000 abstract description 10
- 230000008859 change Effects 0.000 description 4
- 230000002265 prevention Effects 0.000 description 4
- QVFWZNCVPCJQOP-UHFFFAOYSA-N chloralodol Chemical compound CC(O)(C)CC(C)OC(O)C(Cl)(Cl)Cl QVFWZNCVPCJQOP-UHFFFAOYSA-N 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000013598 vector Substances 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000012790 confirmation Methods 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 238000013481 data capture Methods 0.000 description 1
- 238000013500 data storage Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000008676 import Effects 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
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Classifications
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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
Abstract
The invention discloses a device and a method for rapidly detecting ground faults. The electric leakage detection terminal includes: the signal detection module is used for detecting the test point to be tested in the low-voltage distribution room; the data processing module is used for receiving the detection data of the to-be-tested point of the low-voltage distribution room detected by the signal detection module and processing the detection data to obtain detection information; and the wireless communication module is used for being in communication connection with the handheld terminal. The hand-held terminal includes: the wireless communication module is used for being in communication connection with the electric leakage detection terminal and receiving detection information transmitted by the electric leakage detection terminal; the signal processing module is used for collecting and classifying the received detection information to obtain collected and classified information; and the display module is used for displaying the collected and classified information obtained by the processing of the signal processing module. The invention has simple composition and convenient operation, and realizes the quick troubleshooting of the grounding fault of the transformer area on the premise of no power failure.
Description
Technical Field
The invention belongs to the technical field of power detection, and particularly relates to a device and a method for rapidly detecting a ground fault.
Background
The power supply line of the low-voltage transformer area is generally divided into two to three levels, a plurality of branches are divided between each level, and the line is complex. However, the ground fault is caused by the aging of the line, the electrical fault, the irregular wiring, the single-phase grounding and the like, and the occurrence of the ground fault (electric leakage) generates the electric leakage, which not only can cause the hidden danger of electric touch and wind disaster of personnel, but also can cause the abnormal power supply phenomena of the transformer area, such as the electrification of a neutral wire (or a zero wire), the flicker after the closing of part of energy-saving lamps and the like. Under the condition, rapid first-aid repair of power supply enterprises is often required to be completed, however, the traditional troubleshooting method does not well utilize a multipoint leakage combined confirmation method to perform troubleshooting, but adopts methods such as a 'pull method' and a 'dichotomy' to perform troubleshooting (see 'common faults and treatment of low-voltage distribution networks', Chinese power publishers, 2017.11, ISBN 978-7-51981136-5) and the like, and the biggest defects of the troubleshooting methods are that multiple times of power failure is required, the operation is complex, the efficiency is low, and discontent and complaints of users are easily caused.
Certainly, there are detection systems and methods with application numbers "20151017526101" and publication numbers "CN 201810420769.7" in the prior art, but such systems or methods all need to be connected with a background system or an upper computer, are complex to operate, and are not suitable for fast troubleshooting of ground faults.
Disclosure of Invention
In order to solve the above problems, the present invention provides a device for rapidly detecting a ground fault, which can rapidly detect a ground fault without power failure.
The technical scheme of the invention is as follows: the utility model provides a ground fault quick detection device, includes a plurality of can dismantle connect in each node that awaits measuring in low-voltage distribution room and be used for carrying out the electric leakage detection terminal that tests to each node that awaits measuring in low-voltage distribution room, and with electric leakage detection terminal communication connection's handheld terminal, handheld terminal simultaneously with a plurality of electric leakage detection terminal real-time communication, carry out remote control and test data hierarchical level show and look over.
Preferably, the leakage detecting terminal includes:
the signal detection module is used for detecting the test point to be tested in the low-voltage distribution room;
the data processing module is used for receiving the detection data of the to-be-tested point of the low-voltage distribution room detected by the signal detection module and processing the detection data to obtain detection information;
and the wireless communication module is used for being in communication connection with the handheld terminal.
Preferably, each of the leakage detecting terminals has an id code.
Preferably, the leakage detection terminal includes an automatic relay module and a routing module.
Preferably, the handheld terminal includes:
the wireless communication module is used for being in communication connection with the electric leakage detection terminal and receiving detection information transmitted by the electric leakage detection terminal;
the signal processing module is used for collecting and classifying the received detection information to obtain collected and classified information;
and the display module is used for displaying the collected and classified information obtained by the processing of the signal processing module.
Preferably, the system further comprises a setting module capable of setting the hierarchical relationship of the online terminals and directionally receiving the leakage information, the leakage information refreshing frequency and the leakage data reporting threshold of the specified leakage detection terminal.
The invention also provides a method for rapidly detecting the ground fault, which comprises the following steps:
A. hanging a leakage detection terminal to a low-voltage transformer area bus outgoing line side for starting up, sending an online instruction to a handheld terminal by the leakage detection terminal, and sending leakage information to the handheld terminal;
B. an operator hangs the leakage detection terminal on each branch line of the outgoing line according to the leakage information detected by the leakage detection terminal on the outgoing line side of the main line, starts the machine and goes on line, simultaneously sends the leakage information to the handheld terminal, compares the leakage value detected by the leakage detection terminal on the outgoing line side of the main line, and confirms the branch line with the ground fault;
C. after confirming the ground fault branch line, hanging an electric leakage detection terminal on a user or other branch nodes on the lower side of the branch line by an operator, starting up and putting on line, simultaneously sending electric leakage information to the handheld terminal, comparing electric leakage values detected by the electric leakage detection terminal hung on the side of the upper-stage branch, and confirming the ground fault point or the user; and if the branch detects the leakage value, continuing hanging the leakage detection terminal downwards until confirming the ground fault point or the user.
Preferably, the display module of the handheld terminal can input the mark information of the hanging node after detecting that the leakage detection terminal is on line, and can compare the leakage data of multiple nodes at the same time to quickly determine the leakage point.
Compared with the prior art, the invention has the beneficial effects that:
the invention has simple composition and convenient operation, and realizes the fast troubleshooting of the grounding fault of the transformer area on the premise of no power failure.
Drawings
Fig. 1 is a schematic diagram of a frame of a ground fault (leakage) rapid detection device according to the present invention.
Fig. 2 is a schematic diagram of a method for rapidly detecting a ground fault according to the present invention.
Detailed Description
As shown in fig. 1, the present embodiment is a ground fault (leakage) rapid detection device, which includes a leakage detection terminal and a handheld terminal; the electric leakage detection terminal is detachably hung on each node to be detected in the low-voltage transformer area, and the grounding electric leakage value of each node is detected in real time; the handheld terminal is simultaneously communicated with the plurality of electric leakage detection terminals hung to the nodes in real time, and remote control and test data hierarchical display viewing are carried out.
The leakage detection terminal in this embodiment includes: the device comprises a signal detection module, a data processing module and a wireless communication module; the signal detection module is an open-close type current transformer or a flexible coil with various opening diameters, can be conveniently hung on a node to be detected, collects grounding leakage data of the hung node in real time, converts detected leakage analog data into digital leakage information through the data processing module, and sends the digital leakage information to the handheld terminal through the wireless communication module.
Wherein, handheld terminal can be PDA, cell-phone, panel computer etc. and include: the device comprises a wireless communication module, a signal processing module and a display module; the wireless communication module receives the leakage information from the leakage detection terminals of the hanging nodes, the received leakage information of the leakage detection terminals is collected and classified through the signal processing module, and the leakage value is displayed in a classified mode through the display module, which is shown in figure 2.
The electric leakage detection terminal and the handheld terminal are both powered by batteries and can be directly powered; the wireless communication technology can adopt LoRa, zibge, small wireless, 4G, 5G and the like, the LoRa wireless communication technology is preferred, and the electric leakage detection terminal has an automatic signal relay function.
In this embodiment, the leakage detecting terminal has a unique device number as an identification code.
The handheld terminal also comprises a setting module which can set the hierarchical relationship of the online terminals and only directionally receive the leakage information of the appointed leakage detection terminal, the refresh frequency of the leakage information and the reporting threshold value of the leakage data. The hierarchical relation of the online terminals is set, so that a tester can conveniently check the electric leakage according to the hierarchical relation of the transformer area, and an electric leakage conclusion can be quickly obtained; the method has the advantages that the method sets that only the leakage information of a certain leakage detection terminal or a plurality of leakage detection terminals is received to be focused, so that an operator can check the leakage condition of a certain ground fault point more directly; if the continuous grounding leakage condition is met during troubleshooting, the refreshing frequency of the leakage information can be properly adjusted to be slow, the power consumption of equipment is saved, and if the grounding leakage condition which changes frequently is met, the refreshing frequency of the leakage information needs to be adjusted to be fast, so that the changed leakage value is convenient to capture; meanwhile, the leakage data reporting threshold value is set at the handheld terminal, so that the leakage data of the leakage detection terminal is sent to the handheld terminal when reaching the set value, and the tester can be helped to take priority to treatment.
The leakage information refreshing frequency is matched with leakage value display, if the refreshing frequency is set to be 1s once, the handheld terminal communicates with a plurality of leakage detection terminals hung on a node to be detected or appointed at intervals of 1s in turn and refreshes the leakage information, the sequence of refreshing the leakage detection terminal information can be set, if the leakage detection terminals are acquiescent, the leakage detection terminals are refreshed according to the sequence of online leakage detection terminals, and the display module of the handheld terminal displays the leakage value of each leakage detection terminal according to the refreshing frequency and the sequence classification. Of course, the refresh frequency can be set to be infinitely close to 0s if the communication rate allows, so as to improve the leakage data capture capability.
In order to reflect the consistency of the time of the leakage data caused by the grounding in the transformer area, the leakage detection terminal needs to be subjected to timing processing with the handheld terminal every time the leakage detection terminal is connected to the cable; and the leakage terminals upload according to the set refreshing frequency, namely the leakage values uploaded by all the leakage terminals are the leakage values at the same time point.
The method for rapidly detecting the ground fault by using the device can complete rapid investigation through the following steps:
A. the method comprises the steps that a leakage detection terminal is hung to a low-voltage transformer area bus outgoing line side to be started, the leakage detection terminal sends an online instruction to a handheld terminal, and leakage information is sent to the handheld terminal.
B. An operator hangs the leakage detection terminal on each branch line of the outgoing line according to the leakage information detected by the leakage detection terminal on the main outgoing line side, starts the machine and goes on line, simultaneously sends the leakage information to the handheld terminal, and compares the leakage value detected by the leakage detection terminal on the main outgoing line side; if the leakage value of 1 branch is equal to that of the outgoing main line, the ground fault point appears on the lower side of the branch line; if the sum of 2 or more branch leakage values is equal to the leakage value of the total outgoing line, the lower side of each branch has a ground fault, and the leakage phenomenon of the total outgoing line is caused by the multi-stage branches; if the sum of the electric leakage of the branches is not equal to the electric leakage value of the total outlet, whether a 120-degree phase angle relationship of A, B, C exists among the branches needs to be checked, and if the vector sum is equal to the electric leakage value of the total outlet, the electric leakage of the total outlet is caused by the ground fault under the branches; if the branches have electric leakage and the sum of the electric leakage vectors is not equal to the electric leakage value of the total outgoing line, judging whether the branches have the condition of collinear electric utilization or not, or judging whether the lower sides of the more complex branches have ground faults and the branches have the condition of collinear electric utilization; if all branches on the lower side of the main outlet do not detect leakage values, the grounding fault point is on a line above each branch hanging node and below the hanging node of the main outlet; of course, only a few phenomena for the station area ground fault troubleshooting are listed, and the actually analyzable phenomena are far more than these phenomena.
C. After confirming the ground fault branch line, hanging an electric leakage detection terminal on a user or other branch nodes on the lower side of the branch line by an operator, starting up and putting on line, simultaneously sending electric leakage information to the handheld terminal, comparing electric leakage values detected by the electric leakage detection terminal hung on the side of the upper-stage branch, and confirming the ground fault point or the user; if the branch detects a leakage value, the leakage detection terminal is continuously hung downwards until a ground fault point or a user is confirmed; the above determination method is as described in step B, comparing the leakage value of the branch node whose analysis object is the previous stage, and meanwhile, checking the leakage change condition of the outgoing bus side according to the leakage change of the node, and further confirming that the leakage phenomenon of the outgoing bus is enough caused by the ground fault of the node.
D. After the operator confirms the user with the ground fault, the operator compares the change of the leakage current detected by the leakage current detecting terminal mounted on the user side with the change of the user load, and further determines the specific ground fault point of the user, and the method for judging the user fault point is the method described in the "leakage current detecting device for residential homes" of patent No. ZL 201520796467.1.
E. In extreme cases, such as when the device is used to check the drop line 3 shown in fig. 2, the leakage phenomenon of the main line, the branch 5 and the drop line 3 disappears, it can be determined that the ground fault or the leakage point is on the drop line 3, and it belongs to the intermittent ground fault, and the operation described in the previous step D or the operation described in the patent with publication number CN201510175261.1 can be adopted.
According to the method for rapidly detecting the ground fault, the display module of the handheld terminal can input the mark information of the hanging node through the setting module after the leakage detection terminal is detected to be on line. For example, the main outgoing line three-phase four-wire marked as the first stage, the branch 1 three-phase four-wire of the second stage, the branch 2 three-phase four-wire, etc., and a certain single-phase (a/B/C) user or a certain single-phase (a/B/C) branch of the branches of the third stage, etc., are convenient for the tester to clearly locate the ground fault point, and the display is shown in table 1.
TABLE 1
The power distribution room grounding fault detection method is simple in composition and convenient to operate, and rapid troubleshooting of the power distribution room grounding fault (electric leakage) on the premise of no power failure is achieved.
The leakage detection terminal in this embodiment can also realize functions of online false operation prevention, theft prevention, water prevention, alarm and the like by setting "an online false operation prevention processing device for a pincerlike measuring device" with patent number "ZL 201621179716.3", "an anti-theft type acquisition terminal device and a leakage detection system thereof" with patent number "ZL 201620301778.0", "a waterproof type acquisition terminal device for a leakage detection system" with patent number "ZL 201620408141.1", and "an intelligent alarm leakage detection terminal" with patent number "ZL 20180598743.7"; and the functions of data storage, data clearing, data export, time correction, station area user file import and the like of the electric leakage detection terminal and the handheld terminal are set by the conventional technical means to realize omission of the objects to be checked, and the like, and the functions belong to the protection scope of the invention.
Claims (8)
1. The utility model provides a ground fault short-term test device which characterized in that, includes a plurality of can dismantle connect in each node that awaits measuring in low-voltage distribution room and be used for carrying out the electric leakage detection terminal that tests in each node that awaits measuring in low-voltage distribution room, and with electric leakage detection terminal communication connection's handheld terminal, handheld terminal simultaneously with a plurality of electric leakage detection terminal real-time communication, carry out remote control and test data hierarchical level show and look over.
2. The ground fault rapid detection device according to claim 1, wherein the leakage detection terminal comprises:
the signal detection module is used for detecting the test point to be tested in the low-voltage distribution room;
the data processing module is used for receiving the detection data of the to-be-tested point of the low-voltage distribution room detected by the signal detection module and processing the detection data to obtain detection information;
and the wireless communication module is used for being in communication connection with the handheld terminal.
3. The ground fault rapid detection device according to claim 2, wherein each of the earth leakage detection terminals has an identification code.
4. The ground fault rapid detection device according to claim 2, wherein said earth leakage detection terminal is provided with an automatic relay module and a routing module.
5. The apparatus for rapidly detecting ground fault according to any of claims 1 to 4, wherein the handheld terminal comprises:
the wireless communication module is used for being in communication connection with the electric leakage detection terminal and receiving detection information transmitted by the electric leakage detection terminal;
the signal processing module is used for collecting and classifying the received detection information to obtain collected and classified information;
and the display module is used for displaying the collected and classified information obtained by the processing of the signal processing module.
6. The apparatus according to claim 5, further comprising a setting module capable of setting a hierarchical relationship of on-line terminals, and directionally receiving the leakage information, the refresh frequency of the leakage information, and the reporting threshold of the leakage data of the designated leakage detection terminal.
7. A method for rapidly detecting a ground fault is characterized by comprising the following steps:
A. the method comprises the steps that a leakage detection terminal is hung to a low-voltage transformer area bus outgoing line side to be started, the leakage detection terminal sends an online instruction to a handheld terminal, and leakage information is sent to the handheld terminal;
B. an operator hangs the leakage detection terminal on each branch line of the outgoing line according to the leakage information detected by the leakage detection terminal on the outgoing line side of the main line, starts the machine and goes on line, simultaneously sends the leakage information to the handheld terminal, compares the leakage value detected by the leakage detection terminal on the outgoing line side of the main line, and confirms the branch line with the ground fault;
C. after confirming the ground fault branch line, an operator hangs an electric leakage detection terminal on a user or other branch nodes on the lower side of the branch line, starts up the machine and goes on line, simultaneously sends electric leakage information to the handheld terminal, compares the electric leakage value detected by the electric leakage detection terminal hung on the side of the upper-stage branch, and confirms a ground fault point or a user; and if the branch detects the leakage value, continuing hanging the leakage detection terminal downwards until confirming the ground fault point or the user.
8. The method for rapidly detecting the ground fault as claimed in claim 7, wherein the display module of the handheld terminal can input the mark information of the hanging node after detecting that the leakage detection terminal is on line, and can compare leakage data of multiple nodes simultaneously to rapidly determine the leakage node.
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| CN201910841300.5A CN110609197A (en) | 2019-09-06 | 2019-09-06 | Rapid detection device and method for ground fault |
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| CN201910841300.5A CN110609197A (en) | 2019-09-06 | 2019-09-06 | Rapid detection device and method for ground fault |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114089054A (en) * | 2021-09-30 | 2022-02-25 | 国网浙江省电力有限公司武义县供电公司 | Distributed electric leakage monitoring method |
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Patent Citations (5)
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| CN104833893A (en) * | 2015-04-14 | 2015-08-12 | 国网浙江杭州市萧山区供电公司 | Electric leakage detecting terminal, system, and method |
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