CN212255546U

CN212255546U - Cable joint accessory with built-in double-electrode sensor

Info

Publication number: CN212255546U
Application number: CN202020272219.8U
Authority: CN
Inventors: 刘天绍; 马方容; 杨玺; 甄志明; 温带银; 胡锦辉; 唐信; 钟泳康
Original assignee: Guangdong Power Grid Co Ltd; Jiangmen Power Supply Bureau of Guangdong Power Grid Co Ltd
Current assignee: Guangdong Power Grid Co Ltd; Jiangmen Power Supply Bureau of Guangdong Power Grid Co Ltd
Priority date: 2020-03-06
Filing date: 2020-03-06
Publication date: 2020-12-29
Anticipated expiration: 2030-03-06

Abstract

The utility model relates to a built-in sensor technical field of cable, more specifically relates to a built-in bipolar electrode sensor's cable joint annex. A cable joint accessory with a built-in double-electrode sensor comprises a cable body, a MEMS converter, a lead wire, two metal electrodes and a filling layer, wherein the cable body is cut to expose out of an outer semi-conducting layer, the MEMS converter is tightly attached to the outer semi-conducting layer, the two metal electrodes are respectively positioned on two sides of the MEMS converter and tightly attached to the outer semi-conducting layer, the filling layer covers the MEMS converter, the two metal electrodes and the outer semi-conducting layer, one end of the lead wire is connected with the MEMS converter, and the other end of the lead wire penetrates through the filling layer. The utility model discloses a biplate metallic foil constitutes bipolar electrode coupling partial discharge signal, compares and to gather more stable effectual signals in single electric level, and security, resistance to pressure, leakproofness are good.

Description

Cable joint accessory with built-in double-electrode sensor

Technical Field

The utility model relates to a built-in sensor technical field of cable, more specifically relates to a built-in bipolar electrode sensor's cable joint annex.

Background

With the rapid development of national economy and science and technology, electric power has received close attention of the country as clean energy, and high-voltage cable is one of the important components of electric power system, and the online monitoring of partial discharge of it is the important means of guaranteeing reliable operation of power cable, has very important meaning. The partial discharge detection of the power cable accessory can reflect the insulation condition of the power cable accessory, find the insulation defect in advance, determine the position of the defect, carry out urgent repair and maintenance in time and effectively improve the operation reliability of the power cable. The proportion of operating faults of the high-voltage cable caused by faults of cable accessories (including intermediate joints and terminal joints) is up to 70%, and the high-voltage cable joint plays an important role in cable operation and also becomes a weak link of a part where the operating faults mainly occur and cable insulation. The electrical insulation properties of the cable accessories themselves, as well as the quality of the cable and the cable installation process, environmental influences, etc., can cause cable operational failures. Once a fault occurs, a certain economic loss and maintenance consumption are caused.

At present, partial discharge monitoring is mainly carried out through sensing devices such as a capacitive sensor, an inductive sensor and an antenna sensor in China, but the partial discharge monitoring has certain problems and is not high in detection precision. The external sensor is interfered by external electromagnetic signals, so that the external sensor is low in detection sensitivity and poor in anti-interference capability, and cannot be applied to online monitoring for a long time. The traditional built-in sensor uses a single electrode to detect partial discharge, and collectable signals are limited, can be interfered by signals and cannot collect signals accurately and sensitively.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to overcome current built-in sensor monolithic electrode and collect the shortcoming of signal accurate sensitive inadequately, provide a cable joint annex of built-in bipolar electrode sensor.

In order to solve the technical problem, the utility model discloses a technical scheme is: a cable joint accessory with a built-in double-electrode sensor comprises a cable body, a MEMS converter, a lead wire, two metal electrodes and a filling layer, wherein the cable body is cut to expose out of an outer semi-conducting layer, the MEMS converter is tightly attached to the outer semi-conducting layer, the two metal electrodes are respectively positioned on two sides of the MEMS converter and tightly attached to the outer semi-conducting layer, the filling layer covers the MEMS converter, the two metal electrodes and the outer semi-conducting layer, one end of the lead wire is connected with the MEMS converter, and the other end of the lead wire penetrates through the filling layer. The two metal electrodes are directly arranged on the outer semi-conducting layer of the cable main body to form a capacitance sensor, partial discharge signals are sensed in an electrostatic coupling mode, the capacitance sensor formed by the two metal electrodes transmits the signals to an MEMS (micro electro mechanical system) converter tightly attached to the metal electrodes, and then the signals are transmitted out through a lead connected with the MEMS converter.

Further, the cable main body sequentially comprises an inner semi-conducting layer, an insulating layer, an outer semi-conducting layer and an outer sheath from inside to outside, and the outer semi-conducting layer is exposed after the outer sheath is cut. Therefore, the technical scheme is that the cable is arranged on the outer semi-conducting layer which is cut and exposed on the cable main body, and the exposed outer semi-conducting layer is sealed and protected.

Furthermore, the two metal electrodes are two metal foils, namely a first metal foil and a second metal foil, and the first metal foil and the second metal foil are tightly attached to the outer semi-conducting layer. The first metal foil and the second metal foil both have a size of 3cm × 3 cm. The first metal foil and the second metal foil are both made of aluminum materials or copper materials. Two metal foils are attached to the outer semi-conducting layer to form a double-electrode coupling partial discharge signal, and compared with a single-electrode coupling partial discharge signal, the double-electrode coupling partial discharge signal acquisition circuit can acquire more stable and effective signals.

Further, be equipped with the metal protective housing outside the filling layer, what the metal protective housing adopted is half formula structure, the metal protective housing overlap joint is in on the oversheath. The metal protective shell of the half-type structure surrounds and protects the filling layer, the metal electrode and the MEMS converter, and the metal protective shell is overlapped on the outer sheath of the cable body, so that the stripped opening of the cable body is covered and protected.

Further, a lead sealing seal is adopted between the metal protective shell and the outer sheath.

Further, an outer protection box is arranged on the outer side of the metal protection shell, the metal protection shell is covered by the outer protection box, and the outer protection box is sealed with the outer sheath. The outer protection box and the outer sheath are sealed by epoxy cement. The outer protection box covers the whole metal protection shell, and epoxy cement is used for sealing a gap between the outer protection box and the outer sheath to prevent water from entering.

Further, waterproof sealant is filled between the outer protection box and the metal protection shell, and the other end of the lead sequentially penetrates through the filling layer, the metal protection shell, the waterproof sealant and the outer protection box. The lead wire penetrates through the filling layer, the metal protective shell, the waterproof sealing glue and the outer protective box, transmits signals received by the MEMS converter and is connected with other instruments for reading the signals. The cable main body, the MEMS converter and the metal electrode form a cabin type structure integrated design, and safety and working efficiency are greatly improved.

Compared with the prior art, the beneficial effects of the utility model are that:

firstly, the utility model is protected and sealed layer by a filling layer, a metal protection shell, waterproof sealant and an outer protection box from inside to outside, and has good safety, pressure resistance and sealing property;

secondly, the utility model adopts the metal foil directly arranged on the outer semi-conducting layer, which can effectively shield most interference signals and improve the sensitivity and accuracy of partial discharge detection;

thirdly, the construction process of the utility model does not involve the artificial destruction of the outer semi-conducting layer, the insulation shielding layer and the inner semi-conducting layer of the cable, and adopts the cabin type structure integrated design of the cable main body, thereby greatly improving the safety and the working efficiency;

fourth, the utility model discloses a biplate metallic foil constitutes bipolar electrode coupling partial discharge signal, compares and to gather more stable effectual signals in single electric level.

Drawings

Fig. 1 is a schematic structural diagram of a cable joint accessory with a built-in dual-electrode sensor according to the present invention.

FIG. 2 is a schematic circuit diagram of a cable connector accessory with a built-in dual-electrode sensor

The graphic symbols are illustrated as follows:

1-MEMS converter, 2-first metal foil, 3-second metal foil, 4-lead, 5-filling layer, 6-waterproof sealant, 7-outer protection box, 8-outer sheath, 9-outer semi-conducting layer, 10-insulating layer, 11-inner semi-conducting layer and 12-metal protection shell.

Detailed Description

The present invention will be further described with reference to the following embodiments. Wherein the showings are for the purpose of illustration only and are shown by way of illustration only and not in actual form, and are not to be construed as limiting the present patent; for a better understanding of the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.

The same or similar reference numerals in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if there are the terms "upper", "lower", "left", "right", etc. indicating the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, it is only for convenience of description and simplification of the description, but it is not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and therefore the terms describing the positional relationship in the drawings are only for illustrative purposes and are not to be construed as limitations of the present patent, and those skilled in the art can understand the specific meanings of the terms according to specific situations.

First embodiment

Fig. 1 to 2 show a first embodiment of a cable head accessory with a built-in dual-electrode sensor according to the present invention. A cable joint accessory with a built-in double-electrode sensor comprises a cable main body, an MEMS (micro electro mechanical System) converter 1, a lead 4, two metal electrodes and a filling layer 5, wherein the cable main body sequentially comprises an inner semi-conducting layer 11, an insulating layer 10, an outer semi-conducting layer 9 and an outer sheath 8 from inside to outside, the outer sheath 8 of a part needing a partial discharge element is cut open to expose the outer semi-conducting layer 9, the two metal electrodes are respectively a first metal foil 2 and a second metal foil 3, the first metal foil 2 and the second metal foil 3 are respectively positioned on two sides of the MEMS converter 1, and meanwhile the MEMS converter 1, the first metal foil 2 and the second metal foil 3 are tightly attached to the outer semi-conducting layer 9, so that the first metal foil 2, the second metal foil 3 and the MEMS converter 1 are in contact conduction. The filling layer 5 is made of silicon rubber, and the gap of the opened outer sheath 8 is filled by the filling layer 5. One end of the lead 4 is connected with the MEMS transducer 1, and the other end of the lead 4 penetrates out of the filling layer 5. The first metal foil 2 and the second metal foil 3 are made of copper materials, and the two metal foils are directly mounted on the outer semi-conducting layer 9, so that most interference signals can be effectively shielded, and the sensitivity and accuracy of partial discharge detection are improved.

In this embodiment, a metal protective shell 12 is further arranged outside the filling layer 5, the metal protective shell 12 is of a huff structure, the filling layer 5 is wrapped by the upper half and the lower half, the metal protective shell 12 is overlapped at the outer sheath 8, and a gap between the outer sheath 9 and the outer sheath is sealed by using lead sealing.

In addition, an outer protection box 7 is further arranged on the outer side of the metal protection shell 12, the metal protection shell 12 is wrapped by the outer protection box 7, waterproof sealant 6 is filled between the metal protection shell 12 and the outer protection box 7, and a gap between the outer protection box 7 and the outer sheath 8 is sealed by epoxy mud. The other end of the lead 4 sequentially passes through the filling layer 5, the metal protective shell 12, the waterproof sealant 6 and the outer protective box 7. The arrangement ensures that the whole embodiment is protected and sealed layer by layer, and the safety, the pressure resistance and the sealing performance are good.

The working principle of the embodiment is as follows: the first metal foil 2 and the second metal foil 3 are directly mounted and tightly attached on the outer semi-conducting layer 9 to form a capacitance sensor, and a partial discharge signal in the cable body is sensed in an electrostatic coupling mode; in fig. 2, C11 and C12 are the equivalent capacitances between the outer semiconducting layer 9 and the inner semiconducting layer 11; c21 and C22 are that the first metal foil 2 and the second metal foil 3 act as equivalent capacitances between the two metal electrodes and the outer semiconducting layer 9 of the cable; the capacitive sensor formed by the two metal electrodes transmits signals to the MEMS converter 1 connected with the capacitive sensor, and then the signals are transmitted out through a lead 4 connected with the MEMS converter 1. The filling layer 5, the metal protection shell 12, the waterproof sealant 6 and the outer protection box 7 protect and seal the built-in MEMS converter 1 and the two metal electrodes layer by layer, so that the safety, pressure resistance and sealing performance of the embodiment are good, the embodiment adopts a cable body cabin type structure integrated design, and the safety and the working efficiency are greatly improved.

Example 2

This embodiment is similar to embodiment 1, except that the first metal foil 2 and the second metal foil 3 are made of aluminum metal.

It is obvious that the above embodiments of the present invention are only examples for clearly illustrating the present invention, and are not limitations to the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A cable joint accessory of built-in bipolar sensor, includes the cable main part, its characterized in that: still include MEMS converter (1), lead wire (4), two metal electrodes and filling layer (5), the cable main part is cut naked and leaks outer semi-conducting layer (9), MEMS converter (1) hugs closely on outer semi-conducting layer (9), two metal electrodes are located respectively the both sides of MEMS converter (1) are hugged closely on outer semi-conducting layer (9), filling layer (5) cover MEMS converter (1), two metal electrodes and outer semi-conducting layer (9), the one end of lead wire (4) is connected MEMS converter (1), the other end of lead wire (4) passes filling layer (5).

2. The cable head accessory with a built-in dual-electrode sensor as claimed in claim 1, wherein: the cable main body sequentially comprises an inner semi-conducting layer (11), an insulating layer (10), an outer semi-conducting layer (9) and an outer sheath (8) from inside to outside, and the outer semi-conducting layer (9) is exposed after the outer sheath (8) is cut.

3. The cable head accessory with the built-in dual-electrode sensor as claimed in claim 2, wherein: the two metal electrodes are two metal foils, namely a first metal foil (2) and a second metal foil (3), and the first metal foil (2) and the second metal foil (3) are tightly attached to the outer semi-conducting layer (9).

4. A cable joint accessory with a built-in dual-electrode sensor, according to claim 3, wherein: the first metal foil (2) and the second metal foil (3) have the size of 3cm multiplied by 3 cm.

5. The cable head accessory with the built-in dual-electrode sensor as claimed in claim 4, wherein: the first metal foil (2) and the second metal foil (3) are both made of aluminum materials or copper materials.

6. The cable head accessory with the built-in dual-electrode sensor as claimed in claim 2, wherein: a metal protective shell (12) is arranged outside the filling layer (5), the metal protective shell (12) adopts a half structure, and the metal protective shell (12) is lapped on the outer sheath (8).

7. The cable head accessory with a built-in dual-electrode sensor as claimed in claim 6, wherein: and a lead sealing seal is adopted between the metal protective shell (12) and the outer sheath (8).

8. The cable head accessory with a built-in dual-electrode sensor as claimed in claim 7, wherein: the outer side of the metal protective shell (12) is provided with an outer protective box (7), the metal protective shell (12) is covered by the outer protective box (7), and the outer protective box (7) is sealed with the outer sheath (8).

9. The cable head accessory with a built-in dual-electrode sensor as claimed in claim 8, wherein: the outer protection box (7) and the outer sheath (8) are sealed by epoxy cement.

10. The cable head accessory with a built-in dual-electrode sensor as claimed in claim 9, wherein: the outer protection box (7) with fill waterproof sealant (6) between the metal protective housing (12), the other end of lead wire (4) passes in proper order filling layer (5), metal protective housing (12), waterproof sealant (6) and outer protection box (7).