A ground fault rapid detection device and method

Abstract

The present invention discloses a ground fault rapid detection device and method, the device includes a plurality of leakage detection terminals and a handheld terminal connected to the leakage detection terminal. The leakage detection terminal includes: a signal detection module, which is used to detect the test points in the low-voltage substation; a data processing module, which receives the detection data of the test points in the low-voltage substation detected by the signal detection module, and processes the detection data to obtain detection information; a wireless communication module, which is used to communicate with the handheld terminal. The handheld terminal includes: a wireless communication module, which is used to communicate with the leakage detection terminal and receive the detection information transmitted by the leakage detection terminal; a signal processing module, which summarizes and classifies the received detection information to obtain summarized and classified information; a display module, which is used to display the summarized and classified information processed by the signal processing module. The present invention has a simple composition and is easy to operate, and realizes the rapid investigation of substation ground faults without power outages.

Description

Technical Field

[0001] The present invention belongs to the technical field of electric power detection, and in particular relates to a ground fault rapid detection device and method. Background Art

[0002] The low-voltage power supply lines are usually divided into two to three levels, and each level is divided into multiple branches, so the lines are relatively complex. However, line aging, electrical faults, irregular wiring, single-phase grounding and other situations will cause grounding faults. The occurrence of grounding faults (leakage) will generate leakage current, which may not only cause electric shock and wind disaster risks, but also cause the neutral line (or zero line) to be energized, and some energy-saving lamps flicker after being turned off. Abnormal power supply phenomena in the area. In such situations, power supply companies are often required to quickly repair them. However, traditional troubleshooting methods do not make good use of the multi-point leakage combination confirmation method flow for troubleshooting, but use "pull-road method" and "binary method" for troubleshooting (see "Common Faults and Treatment of Low-voltage Distribution Networks", China Electric Power Press, 2017.11, ISBN 978-7-51981136-5). The biggest disadvantage of these troubleshooting methods is that they require multiple power outages, complex operations, low efficiency, and are very likely to cause user dissatisfaction and complaints.

[0003] Of course, there are also detection systems and methods in the prior art, such as application number "20151017526101" and publication number "CN201810420769.7", but such systems or methods need to be connected to the background system or host computer, the operation is complicated, and they are not suitable for the rapid detection of grounding faults. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a ground fault rapid detection device, which can quickly detect the ground fault without power outage.

[0005] The technical solution of the present invention is: a ground fault rapid detection device, including multiple leakage detection terminals that are detachably connected to each node to be tested in a low-voltage substation and are used to test each node to be tested in the low-voltage substation, and a handheld terminal that is communicatively connected to the leakage detection terminal. The handheld terminal simultaneously communicates with multiple leakage detection terminals in real time to perform remote control and hierarchical display and viewing of test data.

[0006] Preferably, the leakage detection terminal comprises:

[0007] A signal detection module is used to detect the test points in the low-voltage area;

[0008] The data processing module receives the detection data of the test point in the low-voltage area detected by the signal detection module, and processes the detection data to obtain detection information;

[0009] The wireless communication module is used to communicate with the handheld terminal.

[0010] Preferably, each leakage detection terminal has an identity identification code.

[0011] Preferably, the leakage detection terminal is equipped with an automatic relay module and a routing module.

[0012] Preferably, the handheld terminal comprises:

[0013] A wireless communication module is used to communicate with the leakage detection terminal and receive detection information transmitted by the leakage detection terminal;

[0014] The signal processing module summarizes and classifies the received detection information to obtain summary and classification information;

[0015] The display module is used to display the summary classification information processed by the signal processing module.

[0016] Preferably, the system further includes a module for setting the hierarchical relationship of online terminals, and for directionally receiving leakage information of designated leakage detection terminals, leakage information refresh frequency, and leakage data reporting threshold.

[0017] The present invention also provides a method for quickly detecting a ground fault, comprising the following steps:

[0018] A. Mount the leakage detection terminal on the main outgoing line side of the low-voltage station area and turn it on. The leakage detection terminal sends an online instruction to the handheld terminal and sends the leakage information to the handheld terminal;

[0019] B. The operator installs a leakage detection terminal on each branch line of the main outgoing line according to the leakage information measured by the leakage detection terminal on the main outgoing line side, turns it on and goes online, and sends the leakage information to the handheld terminal at the same time. The leakage value detected by the leakage detection terminal on the main outgoing line side is compared to confirm the branch line with the grounding fault;

[0020] C. After the operator confirms the grounding fault branch line, he / she shall install a leakage detection terminal on the user or other branch node below the branch line, turn it on and go online, and send leakage information to the handheld terminal at the same time. The leakage value detected by the leakage detection terminal installed on the upper branch side shall be compared to confirm the grounding fault point or user. If there are still branches that detect leakage values, the leakage detection terminal shall continue to be installed downward until the grounding fault point or user is confirmed.

[0021] Preferably, the display module of the handheld terminal can input the marking information of the mounted node after detecting that the leakage detection terminal is online, and can compare the leakage data of multiple nodes at the same time to quickly determine the leakage point.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0023] The invention has a simple composition and is easy to operate, and can realize rapid troubleshooting of grounding faults in a transformer substation without power outage. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the framework of the ground fault (leakage) rapid detection device of the present invention.

[0025] Figure 2 It is a schematic diagram of the ground fault rapid detection method in the present invention. DETAILED DESCRIPTION

[0026] like Figure 1 As shown, this embodiment is a ground fault (leakage) rapid detection device, including a leakage detection terminal and a handheld terminal; the leakage detection terminal can be detachably mounted on each node to be tested in the low-voltage substation to detect the ground leakage value of each node in real time; the handheld terminal simultaneously communicates with multiple leakage detection terminals mounted on each node in real time to perform remote control and hierarchical display of test data.

[0027] In this embodiment, the leakage detection terminal includes: a signal detection module, a data processing module and a wireless communication module; the signal detection module is an open-and-close current transformer or a flexible coil with a variety of opening diameters, which can be conveniently mounted on the node to be tested, and the ground leakage data of the mounted node is collected in real time. The detected leakage analog data is converted into digital leakage information through the data processing module and sent to the handheld terminal by the wireless communication module.

[0028] The handheld terminal may be a PDA, a mobile phone, a tablet computer, etc. and includes: a wireless communication module, a signal processing module and a display module; the wireless communication module receives leakage information from leakage detection terminals of various mounted nodes, summarizes and classifies the leakage information received from various leakage detection terminals through the signal processing module, and displays the leakage values ​​by classification through the display module, see Figure 2 .

[0029] The leakage detection terminal and handheld terminal mentioned above are both powered by batteries, and can also be directly powered by electricity; the wireless communication technology can adopt LoRa, zibgee, small wireless, 4G, 5G, etc. LoRa wireless communication technology is preferred here, and the leakage detection terminal has an automatic signal relay function.

[0030] In this embodiment, the leakage detection terminal has a unique device number as an identification code.

[0031] The handheld terminal also includes a setting module that can set the hierarchical relationship of online terminals, and only receive leakage information from designated leakage detection terminals in a directional manner, as well as the leakage information refresh frequency and leakage data reporting threshold. Setting the hierarchical relationship of online terminals can facilitate testers to check leakage according to the hierarchical relationship of the substations and quickly draw leakage conclusions; setting to only receive leakage information from one or several leakage detection terminals as a key focus can facilitate operators to more directly view the leakage situation of a certain grounding fault point; for example, for continuous grounding leakage encountered during investigation, the leakage information refresh frequency can be appropriately slowed down to save equipment power consumption; if frequently changing grounding leakage is encountered, the leakage information refresh frequency needs to be increased to facilitate capturing changing leakage values; at the same time, by setting the leakage data reporting threshold on the handheld terminal, the leakage data of the leakage detection terminal is sent to the handheld terminal only when it reaches the set value, which can help testers focus on key issues and give priority to governance.

[0032] The leakage information refresh frequency as described above is combined with the leakage value display. If the refresh frequency is set to once every 1 second, the handheld terminal communicates with multiple leakage detection terminals mounted on the node to be tested or specified every 1 second and refreshes the leakage information. The order of refreshing the leakage detection terminal information can be set. For example, by default, the leakage detection terminal is refreshed according to the order in which the leakage detection terminal goes online. The display module of the handheld terminal displays the leakage value of each leakage detection terminal according to the refresh frequency and order. Of course, the refresh frequency can be set to be infinitely close to 0s under the premise that the communication rate allows, so as to improve the ability to capture leakage data.

[0033] Of course, in order to reflect the consistency of leakage data time caused by grounding in the substation, the leakage detection terminal needs to be synchronized with the handheld terminal every time it goes online; the leakage terminal uploads according to the set refresh frequency, that is, all leakage terminals upload leakage values ​​at the same time point.

[0034] Using the above-mentioned device to perform a rapid ground fault detection method, a rapid check can be completed through the following steps:

[0035] A. Mount the leakage detection terminal on the main outgoing line side of the low-voltage station and turn it on. The leakage detection terminal sends an online command to the handheld terminal and sends the leakage information to the handheld terminal.

[0036] B. The operator installs a leakage detection terminal on each branch line of the main outgoing line according to the leakage information measured by the leakage detection terminal on the main outgoing line, turns on the terminal and sends leakage information to the handheld terminal at the same time, and compares the leakage value detected by the leakage detection terminal on the main outgoing line; if the leakage value of one branch is equal to the leakage value of the main outgoing line, then the grounding fault point appears on the lower side of the branch line; if the sum of the leakage values ​​of 2 or more branches is equal to the leakage value of the main outgoing line, then there is a grounding fault on the lower side of each branch, and the leakage phenomenon of the main outgoing line is caused by the multi-level branches; if the sum of the leakage of several branches is not equal to the leakage value of the main outgoing line, it is necessary to check whether there is A between the branches. The 120° phase angle relationship between B and C, if the vector sum is equal to the leakage value of the main outgoing line, then the leakage of the main outgoing line is caused by the grounding fault under these branches; if there is leakage in several branches and the leakage sum or the leakage vector sum is not equal to the leakage value of the total outgoing line, then determine whether there are branches with common power supply, or more complex situations where there are grounding faults on the lower side of several branches and several branches with common power supply; if no leakage value is detected in all branches on the lower side of the main outgoing line, then the grounding fault point is on the line above the mounting node of each branch and below the mounting node of the main outgoing line; of course, only a few phenomenon judgments of grounding fault troubleshooting in the substation are listed, and there are actually far more phenomena that can be analyzed.

[0037] C. After the operator confirms the grounding fault branch line, he / she shall install a leakage detection terminal on the user or other branch nodes below the branch line, turn on the terminal and go online, and send leakage information to the handheld terminal at the same time, compare the leakage value detected by the leakage detection terminal installed on the upper branch side, and confirm the grounding fault point or user; if there are other branches that detect leakage values, continue to hang leakage detection terminals downward until the grounding fault point or user is confirmed; the above judgment method is as described in step B, and the comparison and analysis object is the leakage value of the upper branch node. At the same time, the leakage change on the main outgoing line side can be checked according to the leakage change of the node, and further confirm that the leakage phenomenon of the main outgoing line is caused by the grounding fault of the node.

[0038] D. After the operator confirms the user with the grounding fault, the operator further determines the specific grounding fault point of the user by comparing the change in the leakage value detected by the leakage detection terminal mounted on the user side with the change in the user's load. The method for determining the user's fault point is as described in the "Residential Household Leakage Detection Device" with patent number "ZL 201520796467.1".

[0039] E. Extremely, for example, when using this device to detect Figure 2 When the household line 3 is touched, the leakage phenomenon of the main outgoing line, branch 5 and household line 3 disappears at the same time. It can be determined that the grounding fault or the leakage point is in the household line 3, and it is an intermittent grounding fault. The operation described in the previous step D or the operation described in the patent with publication number CN201510175261.1 can be adopted.

[0040] The display module of the handheld terminal in the ground fault rapid detection method can input the marking information of the mounting node through the setting module after detecting that the leakage detection terminal is online. For example, the marking is the main outgoing line three-phase four-wire of the first level, the No. 1 branch three-phase four-wire and No. 2 branch three-phase four-wire of the second level, and a single-phase (A / B / C) user or a single-phase (A / B / C) branch of a certain branch of the third level, so that the tester can clearly locate the ground fault point, and the display is shown in Table 1.

[0041] Table 1

[0042]

[0043] The implementation scheme is simple in composition and easy to operate, and can realize the rapid troubleshooting of grounding faults (leakage) in the substation without power outage.

[0044] The leakage detection terminal in this embodiment can also realize the functions of online anti-false operation, anti-theft, waterproof, alarm, etc. through the settings of "online anti-false operation processing device for clamp measuring equipment" with patent number "ZL 201621179716.3", "anti-theft type acquisition terminal device and leakage detection system thereof" with patent number "ZL 201620301778.0", "waterproof type acquisition terminal device for leakage detection system" with patent number "ZL 201620408141.1", and "a leakage detection terminal with intelligent alarm" with patent number "ZL 20180598743.7". And the data storage, data clearing, data export, time calibration, and import of user files of the area into the handheld terminal of the leakage detection terminal and the handheld terminal are set by conventional technical means to realize the functions of missing inspection objects, etc., which should all belong to the protection scope of the present invention.

Claims

1. A method for rapid detection of ground faults, characterized in that: Use the ground fault fast detection device to detect through the following steps: A. Mount the leakage detection terminal on the main outgoing line side of the low-voltage station area and turn it on. The leakage detection terminal sends an online instruction to the handheld terminal and sends the leakage information to the handheld terminal; B. The operator installs a leakage detection terminal on each branch line of the main outgoing line according to the leakage information measured by the leakage detection terminal on the main outgoing line side, turns on the terminal and sends the leakage information to the handheld terminal at the same time, and compares the leakage value detected by the leakage detection terminal on the main outgoing line side to confirm the branch line with grounding fault: If the leakage value of one of the branches is equal to the leakage value of the main outgoing line, the ground fault point appears on the lower side of the branch line; If the sum of the leakage values ​​of two or more branches is equal to the leakage value of the main outgoing line, then ground faults are present on the lower sides of these branches, and the leakage of the main outgoing line is caused by these branches; If the sum of the leakage currents of several branches is not equal to the leakage current value of the main outgoing line, it is necessary to check whether there is a 120° phase angle relationship between A, B, and C between the branches. If the vector sum is equal to the leakage current value of the main outgoing line, the leakage current of the main outgoing line is caused by the grounding faults under these branches; If several branches have leakage and the leakage sum or leakage vector sum is not equal to the total outgoing line leakage value, then determine whether there is a common line power supply situation among them, or more complexly, there is a grounding fault on the lower side of several branches, and several branches have a common line power supply situation; If no leakage value is detected in all branches on the lower side of the main outgoing line, the grounding fault point is on the line above the mounting node of each branch and below the mounting node of the main outgoing line; C. After the operator confirms the ground fault branch line, he / she will install a leakage detection terminal on the user or other branch node on the lower side of the branch line, turn it on and go online, and send leakage information to the handheld terminal at the same time. He / she will compare the leakage value detected by the leakage detection terminal installed on the upper branch side to confirm the ground fault point or user. If there are still branches that detect leakage values, he / she will continue to install leakage detection terminals until the ground fault point or user is confirmed. The ground fault rapid detection device includes multiple leakage detection terminals that are detachably connected to each node to be tested in the low-voltage substation and are used to test each node to be tested in the low-voltage substation, and a handheld terminal that is communicatively connected to the leakage detection terminal. The handheld terminal simultaneously communicates with multiple leakage detection terminals in real time to perform remote control and hierarchical display and viewing of test data.

2. The ground fault rapid detection method according to claim 1, characterized in that: The display module of the handheld terminal can input the marking information of the mounted node after detecting that the leakage detection terminal is online, and can compare the leakage data of multiple nodes at the same time to quickly determine the leakage point.

3. A ground fault rapid detection device, characterized in that: It includes multiple leakage detection terminals that are detachably connected to each node to be tested in the low-voltage area and are used to test each node to be tested in the low-voltage area, and a handheld terminal that is communicatively connected to the leakage detection terminal. The handheld terminal simultaneously communicates with multiple leakage detection terminals in real time to perform remote control and hierarchical display and viewing of test data; The handheld terminal comprises: A wireless communication module is used to communicate with the leakage detection terminal and receive detection information transmitted by the leakage detection terminal; The signal processing module summarizes and classifies the received detection information to obtain summary and classification information; A display module, used to display the summary classification information processed by the signal processing module; It also includes a setting module that can set the hierarchical relationship of online terminals, directionally receive leakage information of designated leakage detection terminals, leakage information refresh frequency and leakage data reporting threshold.

4. The ground fault rapid detection device according to claim 3, characterized in that: The leakage detection terminal comprises: A signal detection module is used to detect the test points in the low-voltage area; The data processing module receives the detection data of the test point in the low-voltage area detected by the signal detection module, and processes the detection data to obtain detection information; The wireless communication module is used to communicate with the handheld terminal.

5. The ground fault rapid detection device according to claim 4, characterized in that: Each leakage detection terminal has an identity identification code.

6. The ground fault rapid detection device according to claim 3, characterized in that: The leakage detection terminal is provided with an automatic relay module and a routing module.

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