Non-intrusive signal injection cable grounding loop detection device

Abstract

The utility model discloses a non-intrusive signal injection cable grounding loop detection device, which belongs to the technical field of electrical equipment state detection and comprises a signal injection and measurement device and a choke device. The signal injection and measurement device comprises a flexible electrode plate, a signal generation unit, a measurement unit and a signal connecting line, the flexible electrode plate is connected with the signal generation unit through the signal connecting line, and the measurement unit is connected with the signal generation unit and used for obtaining an injection signal applied to the flexible electrode plate and a reflection signal coupled with the electrode plate. According to the utility model, through a non-intrusive detection mode, detection of a cable grounding loop in operation is realized.

Description

Technical Field

[0001] This utility model relates to the field of power equipment condition detection technology, and more specifically to a non-invasive signal injection cable grounding loop detection device. Background Technology

[0002] In today's society, electricity has become a core energy source for production and daily life, and ensuring a safe and stable power supply is a core task of national security. Cable lines, as key channels for power transmission, play a vital role in areas with high electricity demand, such as cities, factories, and mining areas. However, due to constraints imposed by construction techniques and external environmental factors, grounding circuits in cables often experience grounding anomalies, such as abnormal grounding and poor grounding. These problems disrupt the current and voltage balance within the cable's metallic shielding layer, leading to overheating or overvoltage, and ultimately threatening the safe operation of the cable system.

[0003] For routine monitoring and maintenance of cable grounding circuits, existing technologies mainly include circulating current anomaly detection, grounding voltage measurement, circuit resistance testing, leakage current analysis, grounding impedance assessment, and insulation resistance inspection. However, except for grounding impedance testing, other methods often struggle to accurately pinpoint abnormal grounding points. Even more challenging is that these detection methods are mostly contact-based, sometimes requiring power outages, which not only increases operational risks but also prevents routine maintenance monitoring due to limitations imposed by power outage periods.

[0004] Therefore, providing a cable grounding loop detection device that can be implemented through signal injection without direct contact is a problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0005] In view of this, the present invention provides a non-invasive signal injection cable grounding loop detection device, which can inject and measure signals in a non-invasive manner, thereby realizing the measurement of the grounding loop of the running cable.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A non-invasive signal injection cable grounding loop detection device includes: a signal injection and measurement device and a choke device;

[0008] The signal injection and measurement device includes: a flexible electrode plate, a signal generation unit, a measurement unit, and a signal connection line. The flexible electrode plate is connected to the signal generation unit through the signal connection line, and the measurement unit is connected to the signal generation unit to acquire the injected signal applied to the flexible electrode plate and the reflected signal coupled to the electrode plate.

[0009] Preferably, the signal generating unit includes a matching resistor and a signal generator connected in sequence. The positive terminal of the signal generating device is connected to one end of the matching resistor, and the negative terminal of the signal generating device is grounded. The other end of the matching resistor is connected to the flexible electrode plate through the signal connection line.

[0010] Preferably, the measurement unit includes a data acquisition unit and a sampling resistor. The data acquisition unit is connected to both ends of the sampling resistor to measure and record the voltage across the sampling resistor. One end of the sampling resistor is grounded, and the other end of the sampling resistor is connected to the flexible electrode plate.

[0011] Preferably, the choke device is a ring caliper composed of two semi-circular magnetic rings.

[0012] As can be seen from the above technical solution, compared with the prior art, this utility model discloses a non-invasive signal injection cable grounding loop detection device, which has the following beneficial effects:

[0013] (1) Improved safety and convenience of testing: The non-invasive signal injection technology eliminates the need for direct contact with the cable, avoiding the safety risks that may arise from traditional testing methods. It also simplifies the testing process, making it more convenient and efficient. This non-invasive operation method protects the personal safety of testing personnel and ensures the normal operation of the cable during the testing process, reducing power outage time caused by testing.

[0014] (2) Enhanced reliability of anomaly detection: By injecting signals in a directional manner, this invention can more accurately capture abnormal information in the cable grounding circuit, reducing the complexity of signal analysis and thus significantly improving the reliability of anomaly detection. This directional injection method makes the abnormal signal more prominent, facilitating rapid identification and processing.

[0015] (3) Improved accuracy in anomaly location: Combining the reflectometer principle with non-invasive detection technology and innovative traveling wave blocking technology, this invention can accurately locate anomalies in cable grounding circuits. This high-precision location capability helps maintenance personnel quickly find the problem and take timely measures to repair it, effectively shortening the fault handling time.

[0016] Supports routine operation and maintenance, reducing maintenance costs: This utility model device supports routine inspections without affecting the normal operation of cables, eliminating the need for power outages and thus reducing maintenance costs. Simultaneously, timely detection and handling of potential problems helps prevent major accidents, further ensuring the safe and stable operation of the power grid.

[0017] (4) It has broad application prospects and promotional value: This utility model has achieved technological innovation in the field of cable testing and has significant engineering practice value. It is applicable to the grounding circuit testing of various cable lines, which is of great significance for improving the overall safety and reliability of the power grid. At the same time, its convenient, safe and efficient features make this device have broad application potential in the field of power operation and maintenance. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the principle structure of the device of this utility model;

[0020] Figure 2 This is an installation diagram of the device of this utility model;

[0021] Figure 3 These are the measurement results of the device in a specific embodiment. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] This utility model discloses a non-invasive signal injection cable grounding loop detection device, such as... Figure 1 As shown, it includes: a signal injection and measurement device A and a choke device B;

[0024] The signal injection and measurement device A includes: a flexible electrode plate P1, a signal generation unit S, a measurement unit M, and a signal connection line C1. The flexible electrode plate P1 is connected to the signal generation unit S through the signal connection line C1, and the measurement unit M is connected to the signal generation unit S. It is used to acquire the injection signal applied to the flexible electrode plate P1 and the reflected signal coupled by the electrode plate.

[0025] The flexible electrode plate P1 is a flexible rectangular flat electrode, with its surface protected by an insulating rubber coating. The electrode connects to the lead wire, which, through the insulating rubber, connects to a connector on the outside of the flexible electrode, allowing connection to other devices. The connector uses a standard N-type coaxial connector. During installation, the flexible electrode plate P1 must wrap around and fit snugly against the cable surface, bending naturally with the cable and secured to the cable by surface-mounted straps.

[0026] Furthermore, the choke device is installed near the flexible electrode plate P1, and its installation direction is determined by the position of the cable segment CA under test. If the cable segment CA under test is on the left side of the flexible electrode plate P1, then the choke device B is installed on the right side of the flexible electrode plate P1; and vice versa.

[0027] Specifically, the signal generation unit S includes a matching resistor R1 and a signal generator S1 connected in sequence. The positive terminal of the signal generator S1 is connected to one end of the matching resistor R1, and the negative terminal of the signal generator S1 is grounded. The other end of the matching resistor R1 is connected to the flexible electrode plate P1 through the signal connection line C1. The signal generator S1 is used to generate the required injection signal, and the matching resistor R1 is used to adjust the coupling characteristics of the injection device to ensure that the signal can be coupled to the cable metal shielding layer with maximum power.

[0028] Furthermore, the other end of the matching resistor R1 is connected to a standard N-type coaxial connector via signal line C1. This N-type coaxial connector and the N-type coaxial connector on the flexible electrode plate are a pair of mutually matching N-type coaxial connectors.

[0029] Furthermore, the measurement unit M includes a data acquisition unit M1 and a sampling resistor R2. The data acquisition unit M1 is connected to both ends of the sampling resistor R2 to measure and record the voltage across the sampling resistor R2. The sampling resistor R2 is used to capture the injected signal applied to the flexible electrode plate P1 and the reflected signal coupled from the electrode plate. One end of the sampling resistor R2 is grounded, and the other end is connected to one end of the matching resistor R1 connected to the N-type connector.

[0030] In another embodiment, the choke device B is a ring clamp composed of two semi-circular magnetic rings. The magnetic rings are made of nickel-zinc ferrite, which has a high saturation magnetic induction intensity and a large relative permeability at high frequencies, providing good suppression of injected high-frequency signals. In use, the clamp is opened, the cable passes through the rings of the clamp, and then the clamp is closed to tightly seal the two magnetic rings.

[0031] This utility model is a non-invasive signal injection cable grounding loop detection device, and its installation method during use is as follows: Figure 2 As shown. The cable model in this embodiment is FY-YJLW03-Z 127 / 220kV 1×2500mm. 2 ,according to Figure 2 As shown in the topology, install the flexible electrode plate and choke device, and connect the flexible electrode plate to the detection host. Set the signal generator to produce a pulse signal with a rise time of 50ns, a fall time of 50ns, and a pulse width of 200ns. The measured reflected waveform of the cable grounding loop is as follows. Figure 3 As shown in the diagram, analysis of the reflected waveform reveals an abnormal grounding point in the cable grounding loop at a distance of 232m from the measurement point. On-site investigation revealed damage to the cable's outer sheath at this location, causing a metal connection between the cable's metal shielding layer and the cable support, resulting in the abnormal grounding. The measured distance was 230m; comparing the positioning results, the positioning error of this device is 0.86%.

[0032] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0033] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A non-invasive signal injection cable grounding loop detection device, characterized in that, include: Signal injection and measurement devices and choke devices; The signal injection and measurement device includes: a flexible electrode plate, a signal generation unit, a measurement unit, and a signal connection line. The flexible electrode plate is connected to the signal generation unit through the signal connection line, and the measurement unit is connected to the signal generation unit to acquire the injected signal applied to the flexible electrode plate and the reflected signal coupled to the electrode plate.

2. The cable grounding loop detection device with non-invasive signal injection according to claim 1, characterized in that, The signal generating unit includes a matching resistor and a signal generator connected in sequence. The positive terminal of the signal generator is connected to one end of the matching resistor, and the negative terminal of the signal generator is grounded. The other end of the matching resistor is connected to the flexible electrode plate through the signal connection line.

3. The cable grounding loop detection device with non-invasive signal injection according to claim 1, characterized in that, The measurement unit includes a data acquisition unit and a sampling resistor. The data acquisition unit is connected to both ends of the sampling resistor to measure and record the voltage across the sampling resistor. One end of the sampling resistor is grounded, and the other end of the sampling resistor is connected to the flexible electrode plate.

4. The cable grounding loop detection device with non-invasive signal injection according to claim 1, characterized in that, The choke device is a ring clamp composed of two semi-circular magnetic rings.

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