A detachable clamp for power distribution network current leakage measurement

Abstract

The application discloses a detachable clamp for current leakage measurement of a power distribution network, which comprises a first clamping piece, a second clamping piece and a rotating shaft; the fixed ends of the first clamping piece and the second clamping piece are connected through the rotating shaft, and a spring is arranged in the rotating shaft; the clamping ends of the first clamping piece and the second clamping piece are respectively provided with corresponding first clamping portions and second clamping portions; one end of each of the first clamping portion and the second clamping portion close to each other is provided with a semi-annular groove, and a conductive metal sheet is arranged in the semi-annular groove; one end of the conductive metal sheet is connected with the semi-annular groove through an elastic element, and the other end of the conductive metal sheet extends out of the semi-annular groove and is connected with a cable; and the first clamping portion and the second clamping portion are oppositely arranged to form an annular clamping space for clamping the cable. The clamp can effectively solve the problem that the copper sheet is not closely attached to the surface of the cable and is loose during current leakage measurement, and the accuracy of cable insulation detection is improved.

Description

Technical Field

[0001] This invention belongs to the field of cable measurement technology, specifically relating to a detachable clamp for measuring current leakage in power distribution networks. Background Technology

[0002] With the advancement of society, economy, and science and technology, the power supply level of the power grid has gradually improved. The distribution network is a crucial link in my country's power system, directly serving a vast number of electricity customers. Only the stable and safe operation of the distribution network can provide reliable and secure power supply services to users. Cables, as an important component of the distribution network, play a vital role in power transmission, communication, and data transmission. If damaged or faulty cables are not repaired promptly, it can potentially cause large-scale power outages, signal interruptions, and data losses, ultimately endangering the personal safety and property of users. Therefore, the operating condition of cables directly affects the normal operation of the power system, making cable operation and maintenance increasingly important.

[0003] Currently, cable insulation condition testing is a powerful method to ensure the safe operation of power distribution networks. To achieve early warning of potential power cable faults, power workers regularly conduct current leakage measurements on cables. In current leakage measurements, power workers need to use copper strips to adhere to high-voltage cables of different sizes before testing. However, due to the different laying locations of the cables, they may bend, which can easily lead to problems such as loose or insufficient adhesion of the copper strips to the cable surface during measurement, ultimately affecting the accuracy of the measurement results. Furthermore, because of the different cable models, power workers need to cut copper strips of different sizes each time they measure different cable models, which not only greatly affects the testing time but also wastes resources. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a detachable clamp for measuring current leakage in power distribution networks. This clamp can effectively solve the problem that the copper sheet is easily not tightly attached or loose on the cable surface during current leakage measurement, thereby improving the accuracy of cable insulation testing.

[0005] To achieve the above objectives, the present invention can be accomplished by adopting the following technical solution:

[0006] A detachable clamp for measuring current leakage in a power distribution network includes a first clamping member, a second clamping member, and a rotating shaft. The fixed ends of the first and second clamping members are connected via the rotating shaft, and a spring is provided inside the rotating shaft. The clamping ends of the first and second clamping members are respectively provided with corresponding first clamping portions and second clamping portions. A semi-annular groove is provided at one end of each of the first and second clamping portions, and a conductive metal sheet is provided inside the semi-annular groove. One end of the conductive metal sheet is connected to the semi-annular groove via an elastic element, and the other end of the conductive metal sheet extends out of the semi-annular groove and is connected to the cable to be clamped. The first and second clamping portions are arranged opposite to each other to form an annular clamping space for clamping the cable.

[0007] Preferably, the first clamping part is provided with at least two supporting reinforcing ribs, which are evenly distributed at the bottom end of the semi-annular groove of the first clamping part.

[0008] Preferably, the supporting reinforcing ribs are made of highly elastic rubber.

[0009] Preferably, the conductive metal sheet has a semi-annular structure, and the conductive metal sheet matches the semi-annular groove.

[0010] Preferably, the conductive metal sheet is made of copper.

[0011] Preferably, the structures of the first clamping member and the second clamping member are mirror-symmetric.

[0012] Preferably, the connection between the first clamping part and the second clamping part on the side away from the rotating shaft is provided with a serrated groove and a serrated protrusion that matches the serrated groove; during operation, the serrated protrusion is embedded in the serrated groove.

[0013] Preferably, the first clamping member and the second clamping member are respectively provided with a first gripping part and a second gripping part, and the first gripping part and the second gripping part are arranged opposite to each other to form a handle.

[0014] Preferably, both the first clamping member and the second clamping member are made of insulating material.

[0015] Preferably, both the first clamping member and the second clamping member are made of highly elastic rubber.

[0016] The present invention has the following advantages over the prior art:

[0017] (1) The detachable clamp for measuring current leakage in power distribution networks of the present invention, through the cooperation of the first clamping member, the second clamping member and the rotating shaft, makes the conductive copper sheet on the first clamping member and the second clamping member fit tightly with the cable under test, effectively solving the problem of loose or poor fit between the copper sheet and the cable surface during current leakage measurement, thereby improving the accuracy of current leakage measurement.

[0018] (2) The detachable clamp for measuring current leakage in power distribution networks of the present invention has the advantages of small size, simple operation and easy maintenance, which makes it convenient for power practitioners to work outdoors, thereby reducing the workload of power practitioners.

[0019] (3) The first clamping part and the second clamping part of the detachable clamp for measuring current leakage in power distribution network of the present invention are provided with a sawtooth groove and a protrusion at the connection. This setting can greatly adapt to different cable sizes and increase its application range. The hollow design can give it excellent deformation ability. After the first clamping part and the second clamping part are subjected to force, they can deform in all directions to adapt to cables of different sizes, making the measurement results more accurate. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the detachable clamp for measuring current leakage in a power distribution network according to Embodiment 1 of the present invention.

[0021] Figure 2 This is a schematic diagram of the connection structure of the sawtooth groove and the sawtooth protrusion in Embodiment 2 of the present invention.

[0022] Wherein: 1 is the first clamping member; 101 is the first clamping part; 102 is the first gripping part; 2 is the second clamping member; 201 is the second clamping part; 202 is the second gripping part; 3 is the rotating shaft; 4 is the supporting reinforcing rib; 5 is the semi-annular groove; 6 is the conductive metal sheet; 7 is the serrated groove; 8 is the serrated protrusion; 9 is the handle. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0025] In the description of this invention, it should be understood that the terms "upper", "lower", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0026] Example 1:

[0027] like Figure 1 As shown, a detachable clamp for measuring current leakage in a power distribution network includes a first clamping member 1, a second clamping member 2, and a rotating shaft 3. The fixed ends of the first clamping member 1 and the second clamping member 2 are connected by the rotating shaft 3, and a spring is provided inside the rotating shaft 3. The clamping ends of the first clamping member 1 and the second clamping member 2 are respectively provided with corresponding first clamping portions 101 and second clamping portions 201. A semi-annular groove 5 is provided at one end of the first clamping portion 101 and the second clamping portion 201 that are close to each other. A conductive metal sheet 6 is provided in the semi-annular groove 5. One end of the conductive metal sheet 6 is connected to the semi-annular groove 5 through an elastic element, and the other end of the conductive metal sheet 6 extends out of the semi-annular groove 5 and is connected to the cable to be clamped. The first clamping portion 101 and the second clamping portion 201 are arranged opposite to each other to form an annular clamping space for clamping the cable.

[0028] like Figure 1 As shown, the first clamping part 101 is provided with at least two supporting reinforcing ribs 4. The lower end of the supporting reinforcing rib 4 is fixedly installed at the bottom of the first clamping part 101, and the upper end of the supporting reinforcing rib 4 is connected to the bottom end of the semi-annular groove 5 of the first clamping part 101. This arrangement facilitates the deformation of the first clamping part 101 and the second clamping part 201 in all directions after being subjected to force to adapt to cables of different sizes, thereby improving the applicability of the detachable clamp for measuring current leakage in power distribution networks.

[0029] Specifically, the supporting reinforcing rib 4 is made of highly elastic rubber.

[0030] like Figure 1 As shown, the conductive metal sheet 6 has a semi-annular structure and matches the semi-annular groove 5. This arrangement allows the conductive metal sheet 6 to fit tightly against the surface of the cable, thereby improving the performance of the detachable clamp for measuring current leakage in power distribution networks.

[0031] Specifically, the conductive metal sheet 6 is made of copper. Since copper has excellent conductivity, this setting makes it easier for staff to observe current changes more intuitively when measuring the leakage current of the cable, thereby improving the convenience of the detachable clamp used for measuring current leakage in the power distribution network.

[0032] like Figure 1 As shown, the structures of the first clamping member 1 and the second clamping member 2 are mirror-symmetric.

[0033] The first clamping member 1 and the second clamping member 2 are respectively provided with a first gripping part 102 and a second gripping part 202. The first gripping part 102 and the second gripping part 202 are arranged opposite to each other to form a handle 9. This arrangement facilitates the operation of the detachable clamp for measuring current leakage in power distribution networks by power workers.

[0034] Both the first clamping member 1 and the second clamping member 2 are made of insulating material. This arrangement is designed to prevent electrical workers from having personal safety accidents and to improve the safety of the detachable clamp used for measuring current leakage in power distribution networks.

[0035] In this embodiment, both the first clamping member 1 and the second clamping member 2 are made of highly elastic rubber. This is designed so that the first clamping part 101 and the second clamping part 201 can deform in all directions after being subjected to force to adapt to cables of different sizes, so that the copper sheet fits the cable surface better, thereby making the measurement results more accurate.

[0036] The steps for using the detachable clamp for measuring current leakage in power distribution networks are as follows:

[0037] S1. Preparations before installation;

[0038] First, inspect the surface of the cable to be tested, paying particular attention to whether the surface is intact and undamaged. If it does not meet the testing requirements, an alternative testing location must be found. Then, check whether the rotating shaft 3 rotates smoothly, and check whether the performance of the first clamping part 101 and the second clamping part 201 meets the working requirements, and whether the copper sheets are intact and undamaged. After ensuring that all components are functioning normally, the cable can be installed.

[0039] S2. Adjustments before measurement work;

[0040] Apply force to the handle 9 according to the model of the cable to be tested. After the spring of the rotating shaft 3 is stressed, the first clamping part 101 and the second clamping part 201 open to form a clamping space of a certain size. Then, after the cable to be tested is placed into the clamping space, release the handle 9. At this time, the first clamping part 101 and the second clamping part 201 can deform according to the size of the cable to ensure that the cable is completely wrapped. After the cable is clamped, observe whether the copper sheet at the working end of the clamp completely wraps the cable. If it is tightly fitted, it is acceptable.

[0041] S3. Adjustments during testing;

[0042] First, connect the conductor of the cable under test to the high-voltage power supply via a test connection line. Connect the conductive metal piece 6 in the fixture to the protective resistor and ammeter via the test connection line, and finally ground it after forming a circuit with the cable under test. Then check the connection line to ensure that the wiring at the connection point is intact and the grounding is good. Start the high-voltage power supply and linearly boost the voltage so that the output voltage of the high-voltage power supply is 2.5-3 times the phase voltage of the cable, and continue to measure for 15 minutes. The operator compares the leakage current data at 1 minute and 15 minutes respectively. When the leakage current at 1 minute is greater than the leakage current at 15 minutes, the data is considered valid, and the leakage current value at 15 minutes is taken as the leakage current value of the cable under test. In this embodiment, the boost rate of the high-voltage power supply is set to 0.5kV / s-5kV / s.

[0043] S4. After the measurement work is completed;

[0044] After the staff uses an appropriate level of voltage detector to measure the cable and test area and confirms that it is safe, the staff operates handle 9 to remove the cable, observes that the first clamping part 101 and the second clamping part 201 have recovered, and then puts the detachable clamp used for measuring the current leakage of the power distribution network back into the protection box, thus completing the measurement work.

[0045] Specifically, in this embodiment, the test connection line used for measuring the cable under test is a movable connecting wire with corresponding terminals. In addition, the detachable fixture for measuring current leakage in power distribution networks can be configured to set the terminals on the conductive metal sheet 6 according to test requirements, and corresponding fixed wires can be set on the terminals.

[0046] Example 2:

[0047] like Figure 2 As shown, a detachable clamp for measuring current leakage in a power distribution network includes a first clamping member 1, a second clamping member 2, and a rotating shaft 3. The fixed ends of the first clamping member 1 and the second clamping member 2 are connected by the rotating shaft 3, and a spring is provided inside the rotating shaft 3. The clamping ends of the first clamping member 1 and the second clamping member 2 are respectively provided with corresponding first clamping portions 101 and second clamping portions 201. A semi-annular groove 5 is provided at one end of the first clamping portion 101 and the second clamping portion 201 that are close to each other. A conductive metal sheet 6 is provided in the semi-annular groove 5. One end of the conductive metal sheet 6 is connected to the semi-annular groove 5 through an elastic element, and the other end of the conductive metal sheet 6 extends out of the semi-annular groove 5 and is connected to the cable to be clamped. The first clamping portion 101 and the second clamping portion 201 are arranged opposite to each other to form an annular clamping space for clamping the cable.

[0048] like Figure 2As shown, a serrated groove 7 and a serrated protrusion 8 matching the serrated groove 7 are provided at the connection point of the first clamping part 101 and the second clamping part 201 on the side away from the rotating shaft 3; during operation, the serrated protrusion 8 is embedded in the serrated groove 7. This design allows the fixture to accommodate different cable sizes, improving the practicality of the detachable fixture for measuring power distribution network current leakage; furthermore, the serrated groove 7 and the serrated protrusion 8 make the connection between the first clamping part 101 and the second clamping part 201 more stable, thereby improving the stability of the detachable fixture for measuring power distribution network current leakage.

[0049] The first clamping part 101 is provided with at least two supporting reinforcing ribs 4. The lower end of the supporting reinforcing rib 4 is fixedly installed at the bottom of the first clamping part 101, and the upper end of the supporting reinforcing rib 4 is connected to the bottom end of the semi-annular groove 5 of the first clamping part 101. This arrangement facilitates the deformation of the first clamping part 101 and the second clamping part 201 in all directions after being subjected to force to adapt to cables of different sizes, thereby improving the applicability of the detachable clamp for measuring current leakage in power distribution networks.

[0050] Specifically, the supporting reinforcing rib 4 is made of highly elastic rubber.

[0051] The conductive metal sheet 6 has a semi-annular structure and matches the semi-annular groove 5. This arrangement allows the conductive metal sheet 6 to fit tightly against the surface of the cable, thereby improving the performance of the detachable clamp for measuring current leakage in power distribution networks.

[0052] Specifically, in this embodiment, the conductive metal sheet 6 is made of copper. Since copper has excellent conductivity, this setting makes it easier for staff to observe the current change more intuitively when measuring the leakage current of the cable, thereby improving the convenience of the detachable clamp used for measuring the leakage current of the power distribution network.

[0053] The structures of the first clamping member 1 and the second clamping member 2 are mirror-symmetric.

[0054] The first clamping member 1 and the second clamping member 2 are respectively provided with a first gripping part 102 and a second gripping part 202. The first gripping part 102 and the second gripping part 202 are arranged opposite to each other to form a handle 9. This arrangement facilitates the operation of the detachable clamp for measuring current leakage in power distribution networks by power workers.

[0055] Both the first clamping member 1 and the second clamping member 2 are made of insulating material. This arrangement is designed to prevent electrical workers from having personal safety accidents and to improve the safety of the detachable clamp used for measuring current leakage in power distribution networks.

[0056] In this embodiment, both the first clamping member 1 and the second clamping member 2 are made of highly elastic rubber. This is designed so that the first clamping part 101 and the second clamping part 201 can deform in all directions after being subjected to force to adapt to cables of different sizes, so that the copper sheet fits the cable surface better, thereby making the measurement results more accurate.

[0057] The steps for using the detachable clamp for measuring current leakage in power distribution networks are as follows:

[0058] S1. Preparations before installation;

[0059] First, inspect the surface of the cable to be tested, paying particular attention to whether the surface is intact and undamaged. If it does not meet the testing requirements, an alternative testing location must be found. Then, check whether the rotating shaft 3 rotates smoothly, and check whether the performance of the first clamping part 101 and the second clamping part 201 meets the working requirements, and whether the copper sheets are intact and undamaged. After ensuring that all components are functioning normally, the cable can be installed.

[0060] S2. Adjustments before measurement work;

[0061] Apply force to the handle 9 according to the model of the cable to be tested. After the spring of the rotating shaft 3 is stressed, the first clamping part 101 and the second clamping part 201 open to form a clamping space of a certain size. Then, after the cable to be tested is placed into the clamping space, release the handle 9. At this time, the first clamping part 101 and the second clamping part 201 can deform according to the size of the cable to ensure that the cable is completely wrapped. After the cable is clamped, observe whether the copper sheet at the working end of the clamp completely wraps the cable. If it is tightly fitted, it is acceptable.

[0062] S3. Adjustments during testing;

[0063] First, connect the conductor of the cable under test to the high-voltage power supply via a test connection line. Connect the conductive metal piece 6 in the fixture to the protective resistor and ammeter via the test connection line, and finally ground it after forming a circuit with the cable under test. Then check the connection line to ensure that the wiring at the connection point is intact and the grounding is good. Start the high-voltage power supply and linearly boost the voltage so that the output voltage of the high-voltage power supply is 2.5-3 times the phase voltage of the cable, and continue to measure for 15 minutes. The operator compares the leakage current data at 1 minute and 15 minutes respectively. When the leakage current at 1 minute is greater than the leakage current at 15 minutes, the data is considered valid, and the leakage current value at 15 minutes is taken as the leakage current value of the cable under test. In this embodiment, the boost rate of the high-voltage power supply is set to 0.5kV / s-5kV / s.

[0064] S4. After the measurement work is completed;

[0065] After the staff uses an appropriate level of voltage detector to measure the cable and test area and confirms that it is safe, the staff operates handle 9 to remove the cable, observes that the first clamping part 101 and the second clamping part 201 have recovered, and then puts the detachable clamp used for measuring the current leakage of the power distribution network back into the protection box, thus completing the measurement work.

[0066] Specifically, in this embodiment, the test connection line used for measuring the cable under test is a movable connecting wire with corresponding terminals. In addition, the detachable fixture for measuring current leakage in power distribution networks can be configured to set the terminals on the conductive metal sheet 6 according to test requirements, and corresponding fixed wires can be set on the terminals.

[0067] In the description of this invention, it should be noted that, unless otherwise explicitly specified and agreed, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0068] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A detachable clamp for measuring current leakage in power distribution networks, characterized in that, The device includes a first clamping member, a second clamping member, and a rotating shaft. The fixed ends of the first and second clamping members are connected via the rotating shaft, which contains a spring. The clamping ends of the first and second clamping members are respectively provided with corresponding first and second clamping portions. Both the first and second clamping members are made of highly elastic rubber, and the first clamping portion contains at least two supporting reinforcing ribs. The lower ends of the supporting reinforcing ribs are fixedly installed at the bottom of the first clamping portion, and the upper ends of the supporting reinforcing ribs are connected to the bottom end of the semi-annular groove of the first clamping portion. The supporting reinforcing ribs are made of highly elastic rubber. The first and second clamping portions are adjacent to each other. Each clamping part has a semi-annular groove at one end, and a conductive metal sheet is placed inside the semi-annular groove. One end of the conductive metal sheet is connected to the semi-annular groove through an elastic element, and the other end of the conductive metal sheet extends out of the semi-annular groove and is directly connected to the surface of the cable to be clamped. The conductive metal sheet has a terminal and a fixed wire is provided on the terminal. The connection between the first clamping part and the second clamping part on the side away from the rotating shaft has a serrated groove and a serrated protrusion that matches the serrated groove. During operation, the serrated protrusion is embedded in the serrated groove. The first clamping part and the second clamping part are arranged opposite to each other to form an annular clamping space for clamping the cable.

2. The detachable clamp for measuring current leakage in power distribution networks according to claim 1, characterized in that, The conductive metal sheet has a semi-circular structure and matches the semi-circular groove.

3. The detachable clamp for measuring current leakage in a power distribution network according to claim 2, characterized in that, The conductive metal sheet is made of copper.

4. The detachable clamp for measuring current leakage in a power distribution network according to claim 1, characterized in that, The structures of the first clamping member and the second clamping member are mirror-symmetric.

5. The detachable clamp for measuring current leakage in a power distribution network according to claim 1, characterized in that, The first clamping member and the second clamping member are respectively provided with a first gripping part and a second gripping part, and the first gripping part and the second gripping part are arranged opposite to each other to form a handle.

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