CN211928135U

CN211928135U - Evaluation and processing device for local damp state of 10kV distribution network cable

Info

Publication number: CN211928135U
Application number: CN201922003311.4U
Authority: CN
Inventors: 李文; 项恩新; 王科; 罗俊元; 周善有; 唐兴强; 吴灿辉; 王骏; 孙超; 徐军华
Original assignee: Electric Power Research Institute of Yunnan Power Grid Co Ltd; Lincang Power Supply Bureau of Yunnan Power Grid Co Ltd
Current assignee: Electric Power Research Institute of Yunnan Power Grid Co Ltd; Lincang Power Supply Bureau of Yunnan Power Grid Co Ltd
Priority date: 2019-11-19
Filing date: 2019-11-19
Publication date: 2020-11-13
Anticipated expiration: 2029-11-19

Abstract

The utility model discloses a 10kV distribution network cable local evaluation and processing apparatus who wets state. The evaluation device for the local moisture state of the 10kV distribution network cable can achieve the purpose of quickly testing and judging when the three-phase cable of the urban distribution network is affected with moisture, and the processing device for the local moisture state of the 10kV distribution network cable can complete the repair function of a seriously-affected cable terminal. The beneficial effects of the utility model reside in that, can high-efficiently, accurate, real-time, conveniently make things convenient for the three-phase cable that uses to the city cable pit regional phenomenon of weing to evaluate and restore, avoid because of the cable laid among the cable pit the breakdown problem that the phenomenon of weing leads to, realize the reliable operation of 10kV distribution network.

Description

Evaluation and processing device for local damp state of 10kV distribution network cable

Technical Field

The utility model belongs to the evaluation and the processing field of cable insulation degradation state, concretely relates to evaluation and processing apparatus of 10kV distribution network cable local state of weing.

Background

Crosslinked polyethylene (XLPE) is widely used in power distribution cables because of its simple structure, light weight, good heat resistance, strong load capacity, chemical corrosion resistance, high mechanical strength, and the like. In the XLPE cable which runs in a power grid for a long time, on one hand, the external environment changes indefinitely, so that the cable insulation is affected by factors such as running areas and environments for a long time, and on the other hand, the cable runs under short-time overload, and the internal large-current heat is accumulated, so that the development of cable insulation degradation is accelerated, the surface insulation capability is reduced, the cable is easily corroded by external moisture, the cable is broken down, and the safe running of the power grid is seriously threatened.

Therefore, the work of evaluating the damp degradation state of the cable is done efficiently and conveniently, the fault rate of the 10kV XLPE cable is reduced, a technical device capable of effectively evaluating the local damp state of the 10kV distribution network cable is urgently needed, the device is an evaluation and processing device for the local damp state of the 10kV distribution network cable, the device is simple to operate, the state of the cable can be effectively evaluated through detected leakage current, and the damp problem can be repaired.

SUMMERY OF THE UTILITY MODEL

The utility model aims at supplying a 10kV distribution network cable local evaluation and processing apparatus who wets the state year, can realize that urban distribution network three-phase cable tests fast and judges when appearing the phenomenon of wetting, and 10kV distribution network cable local processing apparatus who wets the state then can accomplish the repair function who wets serious cable termination.

The technical scheme of the utility model is that:

a10 kV distribution network cable local moisture state evaluation and processing device comprises the following main components: the cable terminal comprises an A phase 1 end, a B phase 1 end, a C phase 1 end, an A phase 1 grounding wire, a B phase 1 grounding wire, a C phase 1 grounding wire, a direct grounding box, an A phase 2 grounding wire, a B phase 2 grounding wire, a C phase 2 grounding wire, a grounding protection box, a 2 metal copper nose, a 1 metal copper nose, an A phase 1 mutual inductor, a B phase 1 mutual inductor, a C phase 1 mutual inductor, a 1 data recorder, a 2 data recorder, a computer, a 1 communication cable, a 2 communication cable, an A phase 2 mutual inductor, a B phase 2 mutual inductor, a C phase 2 mutual inductor, a supercharger control cable, an A phase 2 end, a B phase 2 end, a C phase 2 end, a repairing liquid collector, a collecting pipe, a supercharger, an input pipe and a repairing liquid input device; the computer is respectively connected with the data recorder No. 1, the data recorder No. 2 and the supercharger through a communication cable No. 1, a communication cable No. 2 and a supercharger control cable; the repairing liquid input device is tightly hooped on the top of an X-phase No. 1 end terminal shed to be repaired, an expansion adhesive tape and the like can be used for tightly winding to prevent the repairing liquid from leaking, and the repairing liquid input device is connected with the pressurizing supercharger through an input pipe; the repairing liquid collector is tightly hooped at the top of an X-phase No. 2 end terminal umbrella skirt to be repaired, and can be tightly wound by using an expansion adhesive tape and the like to prevent repairing liquid from seeping out, and the repairing liquid collector is connected with a supercharger through a collecting pipe;

according to the routine inspection requirements of a power grid company, in combination with the on-site detection requirements, determining a three-phase indoor cable terminal laid in a cable trench or a three-phase outdoor cable terminal connected to a wire outlet end of electrical equipment such as a transformer in a to-be-detected urban power distribution network, respectively determining an A-phase end, a B-phase end and a C-phase end of the cable terminal, then finding a grounding wire at the position, disconnecting the connection of an A-phase 1 grounding wire, a B-phase 1 grounding wire and a C-phase 1 grounding wire with a direct grounding box, and disconnecting the connection of an A-phase 2 grounding wire, a B-phase 2 grounding wire and a C-phase 2 grounding wire with a grounding protection box;

connect 10kV cable test loop in the moist state: probes of an A-phase 1 mutual inductor, a B-phase 1 mutual inductor and a C-phase 1 mutual inductor are respectively connected to corresponding positions of a 1-number data recorder, an A-phase 2 mutual inductor, a B-phase 2 mutual inductor and a C-phase 2 mutual inductor are respectively connected with corresponding positions of a 2-number data recorder, then are connected with a computer through a 1-number communication cable and a 2-number communication cable, and are continuously connected with the computer and a supercharger through a supercharger control cable;

the third step: collecting leakage current signals on the 6 transformers in real time, collecting current data every 2s for 10min every time, continuously collecting for 9 times, respectively calculating the differences of leakage currents measured by the A-phase 1 mutual inductor and the A-phase 2 mutual inductor, the B-phase 1 mutual inductor and the B-phase 2 mutual inductor, and the C-phase 1 mutual inductor and the C-phase 2 mutual inductor, and obtaining respective leakage current difference coefficients; comparing the A, B, C three-phase test and calculation results to determine the cable terminal X with the most severe moisture degree₀Phase (1);

the fourth step: cutting off the connection of each phase single-core cable terminal and other electrical equipment, and determining X₀The No. 1 end head is connected with the repairing liquid input device, so that the repairing liquid input device is tightly hooped on the X to be repaired₀The top of the shed is terminated at the No. 1 end; x₀The No. 2 end head is connected with the repairing liquid collector, so that the repairing liquid collector is tightly hooped on the X to be repaired₀Starting a supercharger through a computer at the top of the umbrella skirt of the No. 2 end terminal, and repairing the cable terminal seriously affected by moisture;

the fifth step: and after the repair is finished, disconnecting all the testing and repairing connections, reconnecting the connection between each grounding wire and the grounding box, and recovering the connection between each single-core cable terminal and other electrical equipment.

According to the device for evaluating and processing the local moisture state of the 10kV distribution network cable, the used repair liquid is the repair liquid for the water branches of the common cable, the repair liquid is condensed when meeting water to form a protective film, and the repair liquid is allowed to freely flow out in a part without moisture.

The beneficial effects of the utility model reside in that:

1. the utility model discloses a 10kV distribution network cable local state of moisturizing evaluation and processing apparatus can high-efficiently, accurate, real-time, conveniently make an assessment to city cable trench regional three-phase cable that uses phenomenon and state that moisturizes, avoids because of the three-phase cable soaks the breakdown problem that seriously leads to, realizes the reliable operation of distribution network.

2. The utility model discloses a 10kV distribution network cable local evaluation and processing apparatus of the state of weing can carry out early warning and repairing to the inhomogeneous phenomenon of weing of three-phase cable in advance, through test and analysis at the scene to the service performance that further explores three-phase cable provides the foundation for the field personnel.

Drawings

Fig. 1 is a schematic diagram of the wiring of the evaluation and processing device for the local damp state of the cable.

Detailed Description

The present invention is further explained with reference to the flow chart below:

according to the evaluation and processing apparatus wiring diagram of the local damp state of cable of fig. 1, the utility model discloses a concrete step is as follows:

the first step is as follows: building device

A10 kV distribution network cable local moisture state evaluation and processing device comprises the following main components: a phase 1 No. 1 end 1, B phase 1 No. 2 end 2, C phase 1 No. 3 end, A phase 1 grounding wire 4, B phase 1 grounding wire 5, C phase 1 grounding wire 6, direct grounding box 7, A phase 2 grounding wire 8, B phase 2 grounding wire 9, C phase 2 grounding wire 10,

grounding protection box

11, 2 metal copper nose 12, 1 metal copper nose 13, A phase 1 mutual inductor 14, B phase 1 mutual inductor 15, C phase 1 mutual inductor 16, No. 1 data recorder 17, No. 2 data recorder 18, computer 19, No. 1 communication cable 20, No. 2 communication cable 21, A phase 2 mutual inductor 22, B phase 2 mutual inductor 23, C phase 2 mutual inductor 24, supercharger control cable 25, A phase 2 end 26, B phase 2 end 27, C phase 2 end 28, repairing liquid collector 29, collecting pipe 30, supercharger 31, C phase 2 end 28, An input pipe 32, a repair liquid input device 33; wherein, the computer 19 is respectively connected with the data recorder 17 No. 1, the data recorder 18 No. 2 and the supercharger 25 through the communication cable 20 No. 1, the communication cable 21 No. 2 and the supercharger control cable 19; the repairing liquid input device 33 is tightly hooped on the top of the X-phase No. 1 end terminal shed to be repaired, and can be tightly wound by using an expansion adhesive tape and the like to prevent the repairing liquid from leaking, and the repairing liquid input device 33 is connected with the supercharger 31 through the input pipe 32; the repairing liquid collector 29 is tightly hooped on the top of the X phase No. 2 end terminal shed to be repaired, an expansion adhesive tape and the like can be used for tightly winding to prevent the repairing liquid from seeping out, and the repairing liquid collector 29 is connected with the supercharger 31 through the collecting pipe 30. The model of the supercharger 31 is WILO MHI403, and the models of the

data recorders

17 and 18 are MEACON MIK-200D.

The second step is that: preparation for evaluation

According to the routine inspection requirements of a power grid company, in combination with the on-site detection requirements, determining a three-phase indoor cable terminal laid in a cable trench or a three-phase outdoor cable terminal connected to a wire outlet end of electrical equipment such as a transformer in a city power distribution network to be detected, respectively determining an A-phase end 1, a B-phase end 2 and a C-phase end 3 of the cable terminal, then finding a grounding wire at the position, disconnecting a No. 1 grounding wire 4 of the A-phase, a No. 1 grounding wire 5 of the B-phase and a No. 1 grounding wire 6 of the C-phase from a direct grounding box 7, and disconnecting a No. 2 grounding wire 8 of the A-phase, a No. 2 grounding wire 9 of the B-phase and a No. 2 grounding wire 10 of.

The third step: test loop for connecting 10kV cable in damp state

Probes of an A-phase 1 mutual inductor 14, a B-phase 1 mutual inductor 15 and a C-phase 1 mutual inductor 16 are respectively connected to corresponding positions of a 1-number data recorder 17, an A-phase 2 mutual inductor 22, a B-phase 2 mutual inductor 23 and a C-phase 2 mutual inductor 24 are respectively connected to corresponding positions of a 2-number data recorder 18, and then are connected with a computer 19 through a 1-number communication cable 20 and a 2-number communication cable 21, and are continuously connected with the computer 19 and a supercharger 31 through a supercharger control cable 25;

collecting leakage current signals on the 6 transformers in real time, collecting current data every 2s for 10min every time, continuously collecting for 9 times, respectively calculating the differences of the leakage currents measured at the positions of the A-phase 1-type transformer 14 and the A-phase 2-type transformer 22, the B-phase 1-type transformer 15 and the B-phase 2-type transformer 23, and the C-phase 1-type transformer 16 and the C-phase 2-type transformer 24, and obtaining the respective leakage current difference coefficients; comparing the A, B, C three-phase test and calculation results to determine the cable terminal X with the most severe moisture degree₀And (4) phase(s). The calculation procedure is as follows.

The fourth step: calculating a leakage current difference coefficient

1) Calculating the leakage current disturbance rate alpha of the A-phase No. 1 mutual inductor 14_nAnd leakage current disturbance ratio beta of a phase 2 mutual inductor 22_n

na_iCollecting data for the ith time of the A phase No. 1 mutual inductor 14 in the nth acquisition; nb_jIn the nth acquisition, the j-th acquisition of the phase A mutual inductor No. 2 22 is carried out, n, i and j are real numbers, and n belongs to [1,9 ]]，i∈[1,300]，j∈[1,300](ii) a e is a natural constant, 2.7188 is taken; alpha is alpha_nThe leakage current disturbance rate of the a-phase No. 1 transformer 14 in the nth acquisition; beta is a_nThe leakage current disturbance rate of the a-phase No. 2 transformer 22 in the nth acquisition;

2) calculating the leakage current offset ratio lambda of the a-phase 1-th transformer 14_nAnd leakage current offset rate mu of phase-a No. 2 transformer 22_n

na_iData are acquired for the ith time of the phase A mutual inductor No. 1 (14) in the nth acquisition; nb_jIn the nth acquisition, the j-th acquisition of the phase A mutual inductor No. 2 22 is carried out, n, i and j are real numbers, and n belongs to [1,9 ]]，i∈[1,300]，j∈[1,300]；λ_nThe leakage current offset rate of the a-phase No. 1 transformer 14 in the nth round acquisition; mu.s_nThe leakage current offset rate of the a-phase No. 2 transformer 22 in the nth round of acquisition;

3) calculating the leakage current displacement coefficient eta of the A-phase No. 1 mutual inductor 14₁And the leakage current displacement coefficient η of the a-phase No. 2 transformer 22₂

() Representing a matrix; convolution of a representation matrix；M₁、M₂、N₁、N₂Is a leakage current displacement matrix; e is a natural constant, 2.7188 is taken; i | · | purple wind₂Is a matrix 2-norm, | ·| luminance_FIs a matrix F-norm;

4) calculating a leakage current difference coefficient_A

η₁Is the leakage current displacement coefficient, η, of the A-phase No. 1 transformer 14₂Is the leakage current displacement coefficient of the a-phase No. 2 transformer 22;_Ais a leakage current difference coefficient;

the fifth step: according to the content of the fourth step, the leakage current difference coefficient of the B-phase No. 1 mutual inductor 15 and the B-phase No. 2 mutual inductor 23 in the B-phase cable is compared_BAnd the leakage current difference coefficient of the C-phase No. 1 mutual inductor 16 and the C-phase No. 2 mutual inductor 24 in the C-phase cable_CPerform calculations and compare_A、_B、_CJudging the local damp state of the 10kV distribution network cable;

in the ordering_CAnd in the maximum condition, the C-phase cable of the 10kV distribution network cable is most seriously affected by moisture.

And a sixth step: cutting off the connection between each phase of single-core cable terminal and other electrical equipment, and connecting the determined C phase 1 end with a repair liquid input device 33, so that the repair liquid input device 33 is tightly hooped on the top of the umbrella skirt of the C phase 1 end terminal to be repaired; the No. 2C phase end is connected with a repairing liquid collector 29, so that the repairing liquid collector 29 is tightly hooped at the top of a terminal shed of the No. 2C phase end to be repaired, and a supercharger 31 is started through the computer 19 to perform repairing operation on a seriously-damped cable terminal;

the seventh step: and after the repair is finished, disconnecting all the testing and repairing connections, reconnecting the connection between each grounding wire and the grounding box, and recovering the connection between each single-core cable terminal and other electrical equipment.

The above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; those of ordinary skill in the art will understand that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention in its corresponding aspects.

Claims

1. The utility model provides a local evaluation and processing apparatus who wets state of 10kV distribution network cable which characterized in that includes following main component: no. 1A phase end (1), No. 1B phase end (2), No. 1C phase end (3), No. 1A phase grounding wire (4), No. 1B phase grounding wire (5), No. 1C phase grounding wire (6), direct grounding box (7), No. 2A phase grounding wire (8), No. 2B phase grounding wire (9), No. 2C phase grounding wire (10), grounding protection box (11), No. 2 metal copper nose (12), No. 1 metal copper nose (13), No. 1A phase mutual inductor (14), No. 1B phase mutual inductor (15), No. 1C phase mutual inductor (16), No. 1 data recorder (17), No. 2 data recorder (18), computer (19), No. 1 communication cable (20), No. 2 communication cable (21), No. 2A phase mutual inductor (22), No. 2B phase mutual inductor (23), No. 2C phase mutual inductor (24), supercharger control cable (25), An A phase No. 2 end (26), a B phase No. 2 end (27), a C phase No. 2 end (28), a repairing liquid collector (29), a collecting pipe (30), a supercharger (31), an input pipe (32) and a repairing liquid input device (33); wherein, the computer (19) is respectively connected with the data recorder (17) No. 1, the data recorder (18) No. 2 and the supercharger (31) through the communication cable (20) No. 1, the communication cable (21) No. 2 and the supercharger control cable (25); the repairing liquid input device (33) is tightly hooped at the top of the X-phase No. 1 end terminal shed to be repaired, an expansion adhesive tape and the like can be used for tightly winding to prevent the repairing liquid from leaking, and the repairing liquid input device (33) is connected with the supercharger (31) through the input pipe (32); the repairing liquid collector (29) is tightly hooped at the top of an X-phase No. 2 end terminal shed to be repaired, an expansion adhesive tape and the like can be used for tightly winding to prevent the repairing liquid from seeping out, and the repairing liquid collector (29) is connected with a supercharger (31) through a collecting pipe (30);

according to the routine inspection requirements of a power grid company, in combination with the on-site detection requirements, determining a three-phase indoor cable terminal laid in a cable trench or a three-phase outdoor cable terminal connected to a wire outlet end of electrical equipment such as a transformer in a city power distribution network to be detected, respectively determining an A-phase end (1), a B-phase end (2) and a C-phase end (3) of the cable terminal, then finding a grounding wire at the position, disconnecting an A-phase 1 grounding wire (4), a B-phase 1 grounding wire (5) and a C-phase 1 grounding wire (6) from a direct grounding box (7), and disconnecting an A-phase 2 grounding wire (8), a B-phase 2 grounding wire (9) and a C-phase 2 grounding wire (10) from a grounding protection box (11);

connect 10kV cable test loop in the moist state: probes of an A-phase 1 mutual inductor (14), a B-phase 1 mutual inductor (15) and a C-phase 1 mutual inductor (16) are respectively connected to corresponding positions of a 1-phase data recorder (17), an A-phase 2 mutual inductor (22), a B-phase 2 mutual inductor (23) and a C-phase 2 mutual inductor (24) are respectively connected with corresponding positions of a 2-phase data recorder (18), then are connected with a computer (19) through a 1-phase communication cable (20) and a 2-phase communication cable (21), and are continuously connected with the computer (19) and a supercharger (31) through a supercharger control cable (25);

x to be determined₀The No. 1 end head is connected with a repairing liquid input device (33) so that the repairing liquid input device (33) is tightly hooped on the X to be repaired₀The top of the shed is terminated at the No. 1 end; x₀The No. 2 end head is connected with a repairing liquid collector (29) so that the repairing liquid collector (29) is tightly hooped on the X to be repaired₀And starting a booster (31) through a computer (19) at the top of the umbrella skirt of the No. 2 end terminal to repair the cable terminal seriously affected by damp.

2. The device for evaluating and processing the local moisture state of the 10kV distribution network cable according to claim 1, wherein the supercharger (31) is provided with a model of WILO MHI 403.

3. The device for evaluating and processing the local damp state of the 10kV distribution network cable according to claim 1, wherein the model of the data recorder No. 1 (17) and the data recorder No. 1 (18) is MEACON MIK-200D.