Ground fault positioning system and positioning method thereof

Abstract

The invention provides a ground fault positioning system and method, and the system comprises a three-phase collection unit which monitors the current of a line and a ground electric field in real time, and starts wave recording when the electric field changes suddenly and meets a wave recording condition; the collection unit is used for receiving the recording data sent by the three-phase acquisition unit through short-distance wireless communication and synthesizing a zero-sequence waveform to form a recording file; and the master station is used for receiving the recording data uploaded by the collection unit through 4G communication, judging and positioning a fault area and a fault alarm type, and outputting a positioning result and a fault alarm to a mobile phone of a user through a short message. According to the method, multiple transient waveforms can be selected for analysis, section positioning is completed, and the method is suitable for an arc suppression coil grounding system and intermittent faults.

Description

Technical Field

[0001] The present invention mainly relates to the technical field of power grid fault judgment, and in particular to a ground fault locating system and a locating method thereof. Background Art

[0002] With the development of economy and technology and the improvement of living standards, people have higher and higher requirements for the reliability of distribution network power supply. At present, the most common faults in distribution networks are short circuit faults and grounding faults. Among grounding faults, intermittent faults account for a large proportion, and the fault characteristics are not obvious, which has become a major difficulty in fault location in distribution networks. Summary of the invention

[0003] The present invention mainly provides a ground fault location system and a location method thereof to solve the technical problems raised in the above background technology.

[0004] The technical solution adopted by the present invention to solve the above technical problems is:

[0005] A ground fault location system, comprising:

[0006] The three-phase acquisition unit monitors the line current and the electric field to the ground in real time, and starts recording when the electric field suddenly changes and the recording conditions are met;

[0007] The collection unit receives the waveform data sent by the three-phase acquisition unit through short-distance wireless communication, and synthesizes the zero-sequence waveform to form a waveform file;

[0008] The main station receives the recorded data uploaded by the aggregation unit through 4G communication, determines and locates the fault area and fault alarm type, and outputs the positioning result and fault alarm to the user's mobile phone via SMS.

[0009] Further, the three-phase acquisition unit includes a docking head, one end of which is connected to a flexible coil, two ends of which are connected to the docking head, and the ends of the flexible coil are connected to form a ring through the docking head, and a plurality of positioning pieces are connected to the wire body of the flexible coil;

[0010] The positioning member includes a clamp connected to the flexible coil, a protrusion connected to one side surface of the clamp, and a telescopic rod connected to the protrusion. In the present invention, the protrusion is used to provide support for the telescopic rod, so that the multiple telescopic rods are supported on the circuit to be tested, thereby reducing the movement of the wiring harness in this way.

[0011] Furthermore, a latch is inserted at one end of the clip, and a nut is threadedly connected to one end of the latch. In the present invention, the opening of the clip is tightened by the cooperation of the latch and the nut, so that the clip is fastened to the flexible coil.

[0012] Furthermore, the telescopic rod includes a guide cylinder embedded in the protrusion, and a first rod body and a second rod body arranged on one side of the guide cylinder and connected in sequence, and a round head is connected to the side of the second rod body away from the first rod body. In the present invention, the telescopic rod can be extended and retracted by sliding the first rod body on the guide cylinder and the second rod body on the first rod body, so that the telescopic rod can adapt to different specifications of the circuits to be tested through the extension and retraction of the telescopic rod.

[0013] Furthermore, the first rod body and the second rod body have the same structure, the first rod body includes a sliding rod plugged into the guide cylinder, a hollow cylinder connected to one end of the sliding rod, and a sliding sheet connected to the sliding rod and extending to one end inside the guide cylinder, one end of the sliding sheet abuts against a spring, the other end of the spring abuts against the inner wall of the hollow cylinder, the sliding rod is provided with a thread at one end close to the hollow cylinder, and the sliding rod is connected to the guide cylinder through the thread. In the present invention, the sliding rod in the first rod body slides on the guide cylinder, and the sliding rod in the second rod body slides on the hollow cylinder, and the sliding sheet on the sliding rod is pushed by the spring so that the telescopic rod can be telescoped.

[0014] According to the above technical solution of a ground fault location system, a ground fault location method is also provided, comprising the following steps:

[0015] Step 1: The three-phase acquisition unit monitors the line current and the electric field to the ground in real time. When the electric field changes suddenly and the recording conditions are met, the recording data of the three-phase acquisition unit is sent to the collection unit via short-range wireless communication.

[0016] Step 2: The collection unit synthesizes the zero sequence and uploads the data to the main station through G communication. The main station processes the recorded data sent by the collection unit to determine and locate the fault area.

[0017] Step 3: The master station outputs the positioning result and receives the fault SMS.

[0018] Furthermore, the master station triggers the three-phase acquisition unit to record the line electric field and load current data according to the line characteristics at the time of grounding and by collecting the phase electric field strength and current in the line. At the same time, the collection unit summarizes the recorded data of the three-phase acquisition unit to synthesize a zero-sequence waveform, forms a recorded file and sends it to the master station. The fault condition is judged according to the transient and steady-state characteristics of the waveform, and the grounding fault is accurately located through the algorithm module in conjunction with the grounding method and the line topology of the master station, and a fault alarm is issued. The collection unit receives the fault data information sent by the master station.

[0019] Furthermore, the ground fault alarm type is distinguished by the duration of the ground fault within a specified time. The fault alarm types include instantaneous grounding, continuous grounding and permanent grounding. Instantaneous grounding means that the fault duration within 1 minute is less than 12 seconds, continuous grounding means that the fault duration within 1 minute is between 12 seconds and 48 seconds, and permanent grounding means that the fault duration within 1 minute is greater than 48 seconds.

[0020] Furthermore, the master station compares the amplitude and phase of the zero-sequence current within the fault range and outside the fault range to perform section positioning.

[0021] Furthermore, the master station performs section positioning based on the difference in signs of similarities between the zero-sequence current and the zero-sequence electric field within the fault range and outside the fault range.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The present invention can select multiple transient waveforms for analysis and complete section positioning, and is suitable for arc suppression coil grounding systems and intermittent faults. Specifically, the acquisition unit performs short-circuit fault judgment locally, and reports the judgment result to the main station through the collection unit. The main station analyzes the remote signal data reported by the collection unit and locates the fault area. The main station outputs the positioning result, and the mobile phone receives the fault alarm information.

[0024] The present invention will be explained in detail below with reference to the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a flow chart of the present invention;

[0026] Figure 2 It is a structural schematic diagram of the three-phase acquisition unit of the present invention;

[0027] Figure 3 It is a cross-sectional view of the bump of the present invention.

[0028] In the figure: 1. three-phase collection unit; 11. docking joint; 12. flexible coil; 13. positioning piece; 131. clamp; 132. bump; 133. telescopic rod; 1331. guide cylinder; 1332. first rod body; 133a. sliding rod; 133b. hollow cylinder; 133c. sliding sheet; 133d. spring; 133e. thread; 1333. second rod body; 134. latch; 135. nut; 2. collection unit; 3. master station. DETAILED DESCRIPTION

[0029] To facilitate understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings, but the present invention can be implemented in different forms and is not limited to the embodiments described in the text. On the contrary, these embodiments are provided to make the content disclosed in the present invention more thorough and comprehensive.

[0030] It should be noted that when an element is referred to as being "fixed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used in this article are for illustrative purposes only.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which the present invention belongs. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0032] For examples, please refer to the attached Figure 1-3 , a ground fault location system, comprising:

[0033] The three-phase acquisition unit 1 monitors the line current and the electric field to the ground in real time, and starts recording when the electric field suddenly changes and meets the recording conditions;

[0034] The collection unit 2 receives the wave recording data sent by the three-phase collection unit 1 through short-distance wireless communication, and synthesizes the zero-sequence waveform to form a wave recording file;

[0035] The main station 3 receives the recorded data uploaded by the collection unit 2 via 4G communication, determines and locates the fault area and the fault alarm type, and outputs the positioning result and fault alarm to the user's mobile phone via SMS.

[0036] For details, please refer to the attached Figure 1-3 The three-phase acquisition unit 1 includes a docking head 11, one end of which is connected to a flexible coil 12, both ends of which are connected to the docking head 11, and the ends of the flexible coil 12 are connected to form a ring, and a plurality of positioning members 13 are connected to the line of the flexible coil 12;

[0037] The positioning member 13 includes a clamp 131 clamped on the flexible coil 12, a protrusion 132 connected to a side surface of the clamp 131, and a telescopic rod 133 connected to the protrusion 132;

[0038] One end of the clamp 131 is plugged with a plug pin 134, and one end of the plug pin 134 is threadedly connected with a nut 135;

[0039] It should be noted that, in this embodiment, one end of the flexible coil 12 is detachably connected to the docking connector 11, so that the flexible coil 12 can surround the circuit to be tested, and the protrusion 132 can be connected to the flexible coil 12 by setting the clamp 131, and the protrusion 132 provides support for the telescopic rod 133, so that the circuit to be tested is supported by multiple telescopic rods 133, so that the movement of the wiring harness is reduced in this way, and when the flexible coil 12 moves, the feedback formed by the telescopic rod 133 is sensed by the user, so as to adjust the flexible coil 12 in time;

[0040] Furthermore, the clamp 131 allows the flexible coil 12 to pass through its upper opening, so that the flexible coil 12 can be inserted into the clamp 131, and the opening of the clamp 131 is tightened by the cooperation of the latch 134 and the nut 135, so that the clamp 131 is fastened to the flexible coil 12;

[0041] The nut 135 is rotated on the latch 134 to reduce the opening of the clamp 131 , thereby enabling the clamp 131 to rotate so that the telescopic rod 133 faces downward, thereby providing cushioning and protection for the flexible coil 12 .

[0042] For details, please refer to the attached Figure 2 and 3 The telescopic rod 133 includes a guide cylinder 1331 embedded in the protrusion 132, and a first rod body 1332 and a second rod body 1333 which are arranged on one side of the guide cylinder 1331 and are connected in sequence, and a round head 1334 is connected to the side of the second rod body 1333 away from the first rod body 1332;

[0043] The first rod body 1332 and the second rod body 1333 have the same structure. The first rod body 1332 includes a sliding rod 133a plugged into the guide cylinder 1331, a hollow cylinder 133b connected to one end of the sliding rod 133a, and a sliding sheet 133c connected to the sliding rod 133a and extending to one end inside the guide cylinder 1331. One end of the sliding sheet 133c abuts against a spring 133d, and the other end of the spring 133d abuts against the inner wall of the hollow cylinder 133b. One end of the sliding rod 133a close to the hollow cylinder 133b is provided with a thread 133e, and the sliding rod 133a is connected to the guide cylinder 1331 through the thread 133e.

[0044] It should be noted that, in this embodiment, the telescopic rod 133 can be extended and retracted by sliding the first rod 1332 on the guide cylinder 1331 and the second rod 1333 on the first rod 1332, so as to adapt to different specifications of the circuits to be tested by the extension and retraction of the telescopic rod 133.

[0045] Furthermore, the sliding rod 133a in the first rod body 1332 slides on the guide cylinder 1331, and the sliding rod 133a in the second rod body 1333 slides on the hollow cylinder 133b. The sliding sheet 133c on the sliding rod 133a is pushed by the spring 133d, so that the telescopic rod 133 can be extended and retracted.

[0046] like Figure 1-3 As shown, according to the above embodiment, a ground fault location method is also provided, comprising the following steps:

[0047] Step 1: The three-phase acquisition unit 1 monitors the line current and the electric field to the ground in real time. When the electric field changes suddenly and the recording conditions are met, the recording data of the three-phase acquisition unit 1 is sent to the collection unit via short-range wireless communication.

[0048] Step 2: The collection unit 2 synthesizes the zero sequence and uploads the data to the main station 3 via 4G communication. The main station 3 processes the recorded data sent by the collection unit 2 to determine and locate the fault area.

[0049] Step 3: The main station 3 outputs the positioning result and receives the fault SMS.

[0050] Furthermore, the main station 3 triggers the three-phase acquisition unit 1 to record the line electric field and load current data according to the line characteristics at the time of grounding and by collecting the phase electric field strength and current in the line. At the same time, the collection unit 2 summarizes the recorded data of the three-phase acquisition unit to synthesize a zero-sequence waveform, forms a recorded file and sends it to the main station. The fault condition is judged according to the transient characteristics and steady-state characteristics of the waveform, and the grounding fault is accurately located through the algorithm module in conjunction with the grounding method and the main station line topology, and a fault alarm is issued. The collection unit 2 receives the fault data information sent by the main station 3.

[0051] Furthermore, the ground fault alarm type is distinguished by the duration of the ground fault within a specified time. The fault alarm types include instantaneous grounding, continuous grounding and permanent grounding. Instantaneous grounding means that the fault duration within 1 minute is less than 12 seconds, continuous grounding means that the fault duration within 1 minute is between 12 seconds and 48 seconds, and permanent grounding means that the fault duration within 1 minute is greater than 48 seconds.

[0052] Furthermore, the master station 3 compares the amplitude and phase of the zero-sequence current within the fault range and outside the fault range to perform section positioning.

[0053] Furthermore, the master station 3 performs section positioning based on the difference in signs of the similarities between the zero-sequence current and the zero-sequence electric field within the fault range and outside the fault range.

[0054] The above is an exemplary description of the present invention in combination with the accompanying drawings. It is obvious that the specific implementation of the present invention is not limited to the above-mentioned method. As long as such non-substantial improvements are made by adopting the method concept and technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A ground fault location system, characterized in that: include: A three-phase data acquisition unit (1) monitors the line current and the electric field to the ground in real time, and starts recording when the electric field suddenly changes and meets the recording conditions; A collection unit (2) receives the wave recording data sent by the three-phase collection unit (1) via short-distance wireless communication, and synthesizes the zero-sequence waveform to form a wave recording file; The main station (3) receives the recorded data uploaded by the collection unit (2) via 4G communication, determines and locates the fault area and the type of fault alarm, and outputs the positioning result and the fault alarm to the user's mobile phone via SMS.

2. A ground fault location system according to claim 1, characterized in that: The three-phase acquisition unit (1) comprises a docking head (11), one end of the docking head (11) is connected to a flexible coil (12), two ends of the flexible coil (12) are connected to the docking head (11), and the ends of the flexible coil (12) are connected to form a ring through the docking head (11), and a plurality of positioning members (13) are connected to the wire body of the flexible coil (12); The positioning member (13) comprises a clamp (131) clamped on the flexible coil (12), a protrusion (132) connected to a surface of one side of the clamp (131), and a telescopic rod (133) connected to the protrusion (132).

3. A ground fault location system according to claim 2, characterized in that: One end of the clamp (131) is plugged with a latch (134), and one end of the latch (134) is threadedly connected with a nut (135).

4. A ground fault location system according to claim 3, characterized in that: The telescopic rod (133) comprises a guide tube (1331) embedded in the protrusion (132), and a first rod body (1332) and a second rod body (1333) which are arranged on one side of the guide tube (1331) and are connected in sequence, and a round head (1334) is connected to the side of the second rod body (1333) away from the first rod body (1332).

5. A ground fault location system according to claim 4, characterized in that: The first rod body (1332) and the second rod body (1333) have the same structure. The first rod body (1332) includes a sliding rod (133a) plugged into the guide cylinder (1331), a hollow cylinder (133b) connected to one end of the sliding rod (133a), and a sliding sheet (133c) connected to the sliding rod (133a) and extending to one end inside the guide cylinder (1331). One end of the sliding sheet (133c) is abutted against a spring (133d), and the other end of the spring (133d) is abutted against the inner wall of the hollow cylinder (133b). A thread (133e) is provided at one end of the sliding rod (133a) close to the hollow cylinder (133b), and the sliding rod (133a) is connected to the guide cylinder (1331) through the thread (133e).

6. A ground fault location method, used to implement a ground fault location system according to any one of claims 1 to 5, characterized in that: The following steps are involved: Step 1: The three-phase acquisition unit (1) monitors the line current and the electric field to the ground in real time, and starts recording when the electric field suddenly changes and the recording conditions are met, and the recording data of the three-phase acquisition unit (1) is sent to the collection unit via short-range wireless communication; Step 2: The collection unit (2) synthesizes the zero sequence and uploads the data to the main station (3) via 4G communication. The main station (3) processes the recorded data sent by the collection unit (2) to determine and locate the fault area. Step 3: The main station (3) outputs the positioning result and receives the fault SMS.

7. A ground fault location method according to claim 6, characterized in that: The master station (3) triggers the three-phase acquisition unit (1) to record the line electric field and load current data according to the line characteristics when grounded, by collecting the phase electric field strength and current in the line. At the same time, the collection unit (2) aggregates the recorded data of the three-phase acquisition unit into a zero-sequence waveform, forms a recorded file and sends it to the master station. The fault situation is judged according to the transient characteristics and steady-state characteristics of the waveform. The grounding fault is accurately located through the algorithm module in conjunction with the grounding method and the master station line topology, and a fault alarm is issued. The collection unit (2) receives the fault data information sent by the master station (3).

8. A ground fault location method according to claim 6, characterized in that: The ground fault alarm type is distinguished by the duration of the ground fault within a specified time. The fault alarm types include instantaneous grounding, continuous grounding and permanent grounding. Instantaneous grounding means that the fault duration within 1 minute is less than 12 seconds, continuous grounding means that the fault duration within 1 minute is between 12 seconds and 48 seconds, and permanent grounding means that the fault duration within 1 minute is greater than 48 seconds.

9. A ground fault location method according to claim 6, characterized in that: The master station (3) compares the amplitude and phase of the zero-sequence current within the fault range and outside the fault range to perform section positioning.

10. A ground fault location method according to claim 6, characterized in that: The master station (3) performs section positioning based on the difference in signs of the similarity between the zero-sequence current and the zero-sequence electric field within the fault range and outside the fault range.

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