Conversion connector for GIS cable terminal test

Abstract

The present invention relates to a conversion joint for GIS cable terminal test, comprising a high-voltage test lead and a reducer, wherein the two ends of the high-voltage test lead are respectively a GIS end and a vehicle end, and the reducer is threadedly connected to the GIS end, wherein the diameter of one end of the reducer matches the threaded hole of the GIS end of the high-voltage test lead, and the diameter of the other end of the reducer matches the bolt hole of the grounding end of the GIS grounding knife switch. The application of this device can greatly improve the test efficiency and the accuracy of fault location.

Description

Technical Field

[0001] The invention belongs to the technical field of high voltage testing, and relates to a GIS cable terminal testing technology of 110 kV and above, in particular to a conversion joint used for GIS cable terminal testing. Background Art

[0002] The high-voltage power cable fault finding test is the primary diagnostic test item after the cable line trips due to a fault. It is of great significance for discovering whether the internal insulation of the cable main insulation is damp, aged, or has severe partial discharge breakdown, as well as for quickly and accurately finding the fault point.

[0003] When testing the fault finding of the full cable transmission line with GIS incoming lines at both station ends, it is necessary to open the line grounding switch at one station end. Since the test end cannot directly connect the high-voltage test lead to the cable terminal head located in the GIS air chamber, it is necessary to remove the grounding bar of the static contact of the GIS line grounding switch, and then use bolts to connect the high-voltage test lead to perform a pressure test on the tested cable after the line grounding switch is closed. Since the test voltage is high (generally around 30kV to 70kV) and the full cable line is capacitive, this leads to the following problems:

[0004] 1. The faulty cable is a high-resistance fault and the fault point is far away from the cable line. When the grounding bar is removed, the residual charge in the cable is very likely to cause an electric shock accident; or there is a live cable line running in the same slot as the faulty cable, which will cause the risk of induction electric shock to the workers who remove the grounding bar to connect the high-voltage lead;

[0005] 2. Since the grounding lead-out terminal of the static contact of the GIS grounding knife switch cannot ensure a sufficient safety distance from the ground potential (the bolt of the static contact grounding lead-out terminal is short, the opening of the high-voltage test clamp is large and there is no insulation), it is necessary to repeatedly adjust the contact position between the high-voltage test clamp and the bolt and use multiple external insulation to conduct the test. Even so, since the bolt cannot be connected to the static contact of the grounding knife switch, the fault reflection waveform is extremely unsatisfactory, which seriously affects the accurate judgment of the fault point;

[0006] 3. The high-voltage test clamp is stuck on the short bolt, and the insulating tape wrapped around the test clamp is not tight. If the high-voltage lead falls off during the high-voltage test, it is easy to cause casualties and damage to equipment; therefore, it is particularly important to ensure a reliable connection between the high-voltage lead and the static contact bolt of the grounding switch. Summary of the invention

[0007] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a conversion connector for GIS cable terminal testing to solve the problems existing in the full cable line fault finding test process of double-sided GIS cable terminals of 110kV and above.

[0008] The technical solution adopted by the present invention to solve the technical problem is:

[0009] A conversion joint for GIS cable terminal testing comprises a high-voltage test lead and a reducer, wherein the two ends of the high-voltage test lead are a GIS end and a vehicle end respectively, and the reducer is threadedly connected to the GIS end, wherein the diameter of one end of the reducer matches the threaded hole of the GIS end of the high-voltage test lead, and the diameter of the other end of the reducer matches the bolt hole of the grounding end of the GIS grounding switch.

[0010] Moreover, one high-voltage test lead is matched with multiple reducers, and the multiple reducers have the same diameter as the end connected to the GIS end of the high-voltage test lead, but different diameters as the end connected to the grounding end of the GIS grounding switch.

[0011] Moreover, both ends of the high-voltage test lead are respectively wrapped with high-voltage insulating sleeves.

[0012] Moreover, the diameter of the end of the reducer connecting the grounding terminal of the GIS grounding switch is 12-16 mm, and the diameter of the end of the reducer connecting the high-voltage test lead GIS end is 8.7 mm.

[0013] The advantages and positive effects of the present invention are:

[0014] 1. Reduce power outage time and improve power supply reliability. During the on-site test, the high-voltage test clamp is stuck on the short bolt, and the insulation tape wrapped around the test clamp is not tight. If the high-voltage lead falls off during the high-voltage test, it is easy to cause casualties and damage to equipment; and it takes 1-2 hours to disassemble the grounding terminal, adjust the position of the test clamp, and wrap the insulation to fix it. The use of the conversion joint shortens the single test time to 0.5 hours;

[0015] 2. Reduce safety risks and enhance intrinsic safety. Operators hold the conversion connector with an insulating sheath to avoid risks such as high-voltage electric shock;

[0016] 3. Improve work efficiency and positioning accuracy. The application of this device can greatly improve the test efficiency and the accuracy of fault positioning. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is the structural diagram of this conversion joint;

[0018] Figure 2 This is the structural diagram of the reducing screw. DETAILED DESCRIPTION

[0019] The present invention will be further described in detail below with reference to the accompanying drawings and through specific embodiments. The following embodiments are only illustrative and not restrictive, and the protection scope of the present invention cannot be limited thereto.

[0020] A conversion joint for GIS cable terminal testing comprises a high-voltage test lead 3 and a plurality of reducer screws 5, wherein the two ends of the high-voltage test lead are a GIS end 4 and a vehicle end 2 respectively, and the reducer screw is threadedly connected at the GIS end, wherein the diameter of one end of the reducer screw matches the threaded hole of the GIS end of the high-voltage test lead, and the diameter of the other end of the reducer screw matches the bolt hole of the grounding end 6 of the GIS grounding knife switch. When in use, different reducer screws are selected according to the size of the bolt hole of the grounding end of the GIS grounding knife switch, and then one end of the reducer screw is screwed into the conversion joint GIS end of the high-voltage test lead, and then the other end of the reducer screw is screwed into the bolt hole of the grounding end of the GIS grounding knife switch, and finally the vehicle end of the high-voltage test lead is connected to the high-voltage lead end 1 of the test vehicle, thereby realizing safe, reliable and fast electrical connection, and creating conditions for fast finding of cable fault points.

[0021] The outside of the conversion joint is wrapped by a high-voltage insulating sleeve to ensure a safe distance from the grounding terminal during the test and effectively prevent the risk of electric shock when connected to the GIS grounding switch;

[0022] The conversion connector is firmly connected to the high-voltage lead of the test vehicle by docking, which is convenient for installation and removal, and can ensure that the high-voltage lead will not fall off during the test, while saving a lot of test time.

[0023] The present invention improves the test efficiency to a great extent, saves test time, thereby ensuring that the tested equipment is put into operation on time, reducing power outage time, and saving a lot of money for the company.

[0024] The above description is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several modifications and improvements without departing from the inventive concept, which all belong to the protection scope of the present invention.

Claims

1. A conversion joint for GIS cable terminal test, characterized by: The invention comprises a high-voltage test lead and a reducing screw rod, wherein the two ends of the high-voltage test lead are a GIS end and a vehicle end respectively, and the reducing screw rod is threadedly connected to the GIS end, the diameter of one end of the reducing screw rod matches the threaded hole of the GIS end of the high-voltage test lead, and the diameter of the other end of the reducing screw rod matches the bolt hole of the grounding end of the GIS grounding knife switch, the diameter of the end connected to the grounding end of the reducing screw rod and the GIS grounding knife switch is 12-16 mm, and the diameter of the end connected to the GIS end of the high-voltage test lead is 8.7 mm; one high-voltage test lead is matched with multiple reducing screw rods, and the diameters of the ends of the multiple reducing screw rods connected to the GIS end of the high-voltage test lead are the same, and the diameters of the ends connected to the grounding end of the GIS grounding knife switch are different; the two ends of the high-voltage test lead are respectively wrapped with high-voltage insulating sleeves.

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