CN106483413A - High voltage direct current cable dry type easily-testing terminal - Google Patents

Abstract

The utility model relates to a fully dry simple test terminal for high-voltage direct current cables, which relates to the field of high-voltage direct current cable system tests. At present, the simple terminal of the cable factory test cannot be used for complex test research. If the actual line terminal is installed, it needs both professional installation and high cost. The technical solution includes a test sleeve, a DC stress cone and a spring. The test sleeve includes an insulating jacket, a high-voltage shielding electrode sleeve arranged in the middle and upper part of the insulating jacket, a fixed connecting rod arranged in the center of the high-voltage shielding electrode sleeve, an insulating jacket, a high-voltage An insulator is provided between the shielding electrode sleeve and the fixed connecting rod, and the center of the lower insulator in the insulating jacket is provided with a rotary cavity with an open lower end, and an upper flange and a lower flange are respectively provided at the upper end and the lower end of the test sleeve. This technical solution does not require vacuuming, air filling or oil filling, simplifies the terminal structure, reduces installation time, is simple to operate, energy-saving and environmentally friendly, thereby improving work efficiency, and can be reused to reduce test costs.

Description

High-voltage DC cable fully dry simple test terminal

technical field

The invention relates to the field of high-voltage direct current cable system testing, in particular to a fully dry simple test terminal for high-voltage direct current cables.

Background technique

With the rise of wind energy, solar energy and other new energy power generation, coupled with the restrictions on air transmission corridors in modern cities, flexible DC transmission technology has also attracted more and more attention. After successful research and development, China started the construction of a high-voltage flexible direct current transmission demonstration project in 2012. The Nan'ao Island ±160kV multi-terminal flexible DC project constructed by China Southern Power Grid was put into operation in December 2013. The Zhoushan ±200kV multi-terminal project constructed by the State Grid was put into operation in June 2014. The Xiamen DC project was also put into operation in December 2015. As the essential components of DC cable transmission lines, DC cable lines and cable accessories, their performance directly affects the operational reliability of the entire DC transmission and distribution system. The DC cable system is a newly developed product in recent years. There is no uniform inspection method at home and abroad to evaluate the electrical performance of the DC cable system. Most companies conduct factory inspections before the cables leave the factory. For DC cable products, it is generally possible to directly install a simple cable terminal on the product for testing before leaving the factory. This method is to simulate the actual operation of the finished product and is only applicable to conventional factory inspections. If some complex tests cannot meet the requirements. Before leaving the factory, cable accessories are generally installed on a device specially designed for testing or simulated accessories for testing. This device or simulated accessory provides the electrodes required for the test, so that the electric field strength on the preform under test is not less than that of the finished cable accessory at its specified test voltage. If the terminal developed by the cable accessory factory is used to conduct complex tests on the cable system, it will not only increase the research and development cycle, but also increase the test cost. If the simple terminal of the cable factory test is used, complex test research cannot be carried out, and if the actual line terminal is installed, it needs both professional installation and high cost. Therefore, it is necessary to develop a set of simple test terminals that meet the above test requirements.

Contents of the invention

The technical problem to be solved and the technical task proposed by the present invention are to improve and improve the existing technical solutions, and to provide a fully dry simple test terminal for high-voltage DC cables for the purpose of realizing a series of research tests under simulated operating conditions. For this reason, the present invention takes the following technical solutions.

The high-voltage DC cable full-dry simple test terminal includes a test sleeve, a DC stress cone and a spring. The test sleeve includes an insulating jacket, a high-voltage shielding electrode sleeve arranged in the middle and upper part of the insulating jacket, and a high-voltage shielding electrode sleeve. The fixed connecting rod in the center, the insulator is arranged between the insulating jacket, the high-voltage shielding electrode sleeve and the fixed connecting rod, the center of the lower insulating member in the insulating jacket is provided with a rotary cavity with a lower end opening, and the test set The upper end and the lower end of the pipe are respectively provided with a detachable upper flange and a lower flange; the lower end of the fixed connecting rod is electrically connected with a detachable connecting rod, and the lower end of the detachable connecting rod is used to connect with the end of the DC cable under test. The wire core is connected, the DC stress cone and the spring are used to cover the end of the DC cable, and the center hole of the lower flange is provided with fixing bolts for tightening the spring. When in use, simply polish the insulating layer of the DC cable under test, put it into the DC stress cone, fix the detachable connecting rod with the cable core, insert it into the test sleeve, and connect the detachable connecting rod with the DC cable core It is electrically connected with the fixed connecting rod, and finally the spring is installed, and the spring is compressed by the fixing bolt to meet the requirements, and the test voltage is introduced from the fixed connecting rod on the upper part of the test terminal, which can realize effective corresponding testing or related research on the DC cable system test.

As a further improvement and supplement to the above technical solutions, the present invention also includes the following additional technical features.

The upper end of the fixed connecting rod protrudes from the central hole of the upper flange, and a connecting hole perpendicular to the axial direction of the fixed connecting rod is provided at the part above the upper flange. It is convenient to connect the wires and to introduce the test voltage easily.

The lower end of the fixed connecting rod is provided with a blind hole for connecting the detachable connecting rod. Allows for easy internal access to the detachable connecting rod.

The blind hole of the fixed connecting rod is electrically connected with the detachable connecting rod through the contact fingers of the strap. The electrical connection mode of the contact fingers of the strap is stable and reliable.

The fixed connecting rod is integrated with the upper flange and the high-voltage shielding electrode sleeve through an insulating piece, and the fixed connecting rod is electrically connected with the upper flange and the high-voltage shielding electrode sleeve. One-piece connection, no need to disassemble and assemble during work, and the electrical connection is convenient for loading the test voltage to the high-voltage shielding electrode sleeve.

The detachable connecting rod is electrically connected to the core of the DC cable under test through bolts. Since the end of the DC cable under test needs to be plugged and pulled out frequently, common connections are prone to disconnection, and the electrical connection through bolts is simple, convenient, firm and reliable.

The lower end of the high-voltage shielding electrode sleeve is lower than the lower end of the detachable connecting rod. The high-voltage shielding electrode sleeve is longer, and the purpose is to shield and fix the air gap between the connecting rod. Since this part of the air gap is shielded, it will not affect the electrical performance of the test terminal.

The lower end of the insulating member protrudes from the insulating jacket, and the lower flange is covered outside the insulating member. It is convenient for the lower flange to be installed and fixed on the insulator.

The insulating jacket is a rubber shed; the insulating part is epoxy resin. The rubber umbrella skirt increases the creepage distance, has a good creepage adjustment effect, and reduces the probability of leakage, discharge and other failures; epoxy resin is easy to manufacture by injection molding and other processes, and is convenient for gap molding.

Beneficial effects: the simple test terminal not only has the electrical performance of a conventional product terminal, but compared with the existing test terminal, it does not need vacuuming, air filling or oil filling, simplifies the terminal structure, reduces installation time, is simple to operate, energy-saving and environmentally friendly, thereby improving Work efficiency can also be reused to reduce test costs.

Description of drawings

Fig. 1 is a schematic cross-sectional structure diagram of the present invention.

Fig. 2 is a schematic cross-sectional structure diagram of the test sleeve of the present invention.

In the figure: 1-test sleeve; 2-detachable connecting rod; 3-DC cable; 4-DC stress cone; 5-spring; 6-fixing bolt; 101-fixed connecting rod; 102-upper flange; 103- High-voltage shielding electrode sleeve; 104-rubber insulating shed; 105-epoxy parts; 106-lower flange; 107-revolving cavity; 108-connecting hole; 109-blind hole.

detailed description

The technical solution of the present invention will be further described in detail below in conjunction with the accompanying drawings.

As shown in Figure 1-2, the high-voltage DC cable full-dry simple test terminal includes a test sleeve 1, a DC stress cone 4 and a spring 5. The high-voltage shielding electrode sleeve 103 in the middle and upper part, and the fixed connecting rod 101 arranged in the center of the high-voltage shielding electrode sleeve 103, the insulating jacket 104, the high-voltage shielding electrode sleeve 103 and the fixed connecting rod 101 are provided with an insulating member 105, the described The center of the lower insulating part 105 in the insulating jacket 104 is provided with a rotary cavity 107 with an open lower end, and the upper and lower ends of the test sleeve 1 are respectively provided with a detachable upper flange 102 and a lower flange 106; The lower end of the connecting rod 101 is electrically connected with a detachable connecting rod 2, the lower end of the detachable connecting rod 2 is used to connect with the wire core at the end of the measured DC cable 3, and the DC stress cone 4 and spring 5 are used to cover the At the end of the DC cable 3 , a fixing bolt 6 for tightening the spring 5 is provided around the center hole of the lower flange 106 .

In order to connect wires conveniently, the upper end of the fixed connecting rod 101 protrudes from the central hole of the upper flange 102 , and the fixed connecting rod 101 is provided with a connecting hole 108 perpendicular to its axial direction at the position above the upper flange 102 . It is convenient to connect the wires and to introduce the test voltage easily.

In order to facilitate electrical connection, the lower end of the fixed connecting rod 101 is provided with a blind hole 109 for connecting the detachable connecting rod 2 . It is convenient to internally connect the detachable connecting rod 2.

In order to better realize the electrical connection, the blind hole 109 of the fixed connecting rod 101 is electrically connected with the detachable connecting rod 2 through watch strap contacts. The electrical connection mode of the contact fingers of the strap is stable and reliable.

In order to facilitate maintenance and simplify the structure, the fixed connecting rod 101 is integrated with the upper flange 102 and the high-voltage shielding electrode sleeve 103 through an insulator 105, and the connection between the fixed connecting rod 101 and the upper flange 102 and the high-voltage shielding electrode sleeve 103 is electrical connection. Integrated connection, no need to disassemble and assemble during operation, the electrical connection is convenient to load the test voltage to the high-voltage shielding electrode sleeve 103, and no additional wire connection is required, which simplifies the structure.

In order to achieve a firm electrical connection between the tested DC cable 3 and the detachable connecting rod 2 , the detachable connecting rod 2 is electrically connected to the wire core of the tested DC cable 3 through bolts. Because the end of the DC cable 3 under test needs to be plugged and pulled out frequently, common connections are prone to disconnection, and the electrical connection through bolts is simple, convenient, firm and reliable.

In order not to affect the electrical performance of the test terminal, the lower end of the high-voltage shielding electrode sleeve 103 is lower than the lower end of the detachable connecting rod 2 . The high-voltage shielding electrode sleeve 103 is longer, and the purpose is to shield and fix the air gap between the connecting rod 101. Since this part of the air gap is shielded, it will not affect the electrical performance of the test terminal.

In order to facilitate installation and fixing, the lower end of the insulating member 105 protrudes from the insulating jacket 104 , and the lower flange 106 is jacketed outside the insulating member 105 . It is convenient to install and fix the lower flange 106 on the insulator 105 .

In order to improve the electrical performance and achieve better insulation and climbing effects, the insulating jacket 104 is a rubber shed; the insulating member 105 is epoxy resin. The rubber umbrella skirt increases the creepage distance, has a good creepage adjustment effect, and reduces the probability of leakage, discharge and other failures; epoxy resin is easy to manufacture by injection molding and other processes, and is convenient for gap molding.

When in use, simply polish the insulating layer of the DC cable 3 under test, put it into the DC stress cone 4, fix the detachable connecting rod 2 with the cable core, insert it into the test sleeve 1, and connect it with the DC cable 3 core The detachable connecting rod 2 is electrically connected to the fixed connecting rod 101, and finally the spring 5 is installed, and the spring 5 is compressed by the fixing bolt 6 to meet the requirements, and the test voltage is introduced from the fixed connecting rod 101 on the upper part of the test terminal to realize DC The cable 3 system carries out effective corresponding tests or related research experiments.

The full-dry simple test terminal for high-voltage DC cables shown in Figures 1-2 above is a specific embodiment of the present invention, which has already demonstrated the substantive features and progress of the present invention. According to actual use needs, under the inspiration of the present invention, Equivalent modification of its shape, structure and other aspects are all within the scope of protection of this scheme.

Claims (10)

1. High-voltage DC cable full-dry simple test terminal, characterized in that it includes a test sleeve (1), a DC stress cone (4) and a spring (5), and the test sleeve (1) includes an insulating jacket (104 ), the high-voltage shielding electrode sleeve (103) located in the middle and upper part of the insulating jacket (104), the fixed connecting rod (101) located in the center of the high-voltage shielding electrode sleeve (103), the insulating jacket (104), the high-voltage shielding An insulator (105) is provided between the electrode sleeve (103) and the fixed connecting rod (101), and the center of the lower insulator (105) in the insulating jacket (104) is provided with a rotary cavity (107) with an open lower end. ), the upper end of the test casing (1) is connected with an upper flange (102), and the lower end is provided with a detachable lower flange (106); the lower end of the fixed connecting rod (101) is electrically connected with a detachable connecting rod (2), the lower end of the detachable connecting rod (2) is used to connect with the wire core at the end of the tested DC cable (3), and the DC stress cone (4) and spring (5) are used to cover the DC cable At the end of (3), the center hole of the lower flange (106) is provided with fixing bolts (6) for tightening the spring (5). 2. The high-voltage DC cable fully dry simple test terminal according to claim 1, characterized in that: the upper end of the fixed connecting rod (101) protrudes from the center hole of the upper flange (102), and is fixedly connected A connecting hole (108) perpendicular to the axial direction of the rod (101) is provided at the part above the upper flange (102). 3. The high-voltage DC cable fully dry simple test terminal according to claim 2, characterized in that: the lower end of the fixed connecting rod (101) is provided with a blind hole for connecting the detachable connecting rod (2) ( 109). 4. The high-voltage DC cable fully dry simple test terminal according to claim 3, characterized in that: the blind hole (109) of the fixed connecting rod (101) and the detachable connecting rod (2) pass through the table Electrical connections with contacts. 5. The high-voltage DC cable fully dry simple test terminal according to claim 1, characterized in that: the fixed connecting rod (101), the upper flange (102) and the high-voltage shielding electrode sleeve (103) pass through an insulating piece ( 105) is connected in one piece, and the fixed connecting rod (101) is electrically connected to the upper flange (102) and the high-voltage shielding electrode sleeve (103). 6. The high-voltage DC cable full-dry simple test terminal according to claim 1, characterized in that: the detachable connecting rod (2) is electrically connected to the core of the tested DC cable (3) through bolts . 7. The high-voltage DC cable fully dry simple test terminal according to claim 1, characterized in that: the lower end of the high-voltage shielding electrode sleeve (103) is lower than the lower end of the detachable connecting rod (2). 8. The high-voltage DC cable fully dry simple test terminal according to claim 1, characterized in that: the lower end of the insulating member (105) protrudes from the insulating jacket (104), and the lower flange (106) The overcoat is outside the insulator (105). 9. The high-voltage DC cable fully dry simple test terminal according to claim 1, characterized in that: the rotary cavity (107) is provided with an inward slope, and the upper part of the rotary cavity (107) The slope is greater than that of the middle and lower parts. 10. The high-voltage DC cable fully dry simple test terminal according to claim 1, characterized in that: the insulating jacket (104) is a rubber shed; the insulating member (105) is epoxy resin.