JPS6154183B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for testing a cable line withstand voltage.

For cable lines, it is necessary to conduct a withstand voltage test immediately after installation. In the case of long lines,
In an AC withstanding voltage test, the charging current becomes large, requiring a high-capacity withstanding voltage testing device, making the test difficult, so we have no choice but to rely on a DC withstanding voltage test.

By the way, recently, gas insulated switches have been used in various places, and cables are often directly connected to these switches. In some cases, both ends of the cable are connected directly to a gas-insulated switch, and in this case, the terminal ends of both ends of the cable are completely housed within the case of the gas-insulated switch, eliminating any exposed live parts. I end up.

For this reason, it has been proposed to detachably attach a energizing bushing to the case of a gas-insulated switch, connect the conductor of this bushing to the cable terminal C in the case, and perform a DC withstand voltage test on the cable line. However, outdoor bushings are used for power charging, and are difficult to handle due to their large size.

The withstand voltage test method for a cable line according to the present invention is a method in which a gas-filled termination part can be used as the energizing termination part, and the cable line with the cable termination part provided in the gas-filled equipment case is When performing a voltage test, cover the energizing terminal part of the energizing set with the energizing power supply for the above cable terminal part with a test case, airtightly connect the test case and the above equipment case, and After evacuation, gas is filled inside the test case, and then the electrical connection between the energizing end and the cable end is cut off by inserting the energizing switching device attached to the test case. , conduct a withstand voltage test of the energizing set using the energizing power supply, and then operate the energizing switching device to electrically connect the energizing terminal and the cable terminal, and then This method is characterized in that a withstand voltage test of the cable line is performed using an electric power set.

The present invention will be explained below with reference to the drawings.

FIG. 1 shows the state of a cable line during a withstand voltage test according to the present invention. FIG. 2 shows a charging set used in the present invention, which includes a DC voltage generator 1, a charging cable 2, a charging cable terminal part 3, a charging cable gas intermediate terminal part 4, and a test case 41. The test case 41 is provided with a power supply switching device S.

FIG. 3 shows an example of the energization switching device S, in which 51 is a handle airtightly attached to a test case;
Reference numeral 2 denotes an adapter fitting having a threaded portion on the inner surface, and the fitting 52 is connected to the handle 5 through an insulating rod 53.
It is tied to 1. 54 is a sliding metal rod, which has a threaded portion 541 at one end;
1 is screwed onto an adapter fitting 52. Reference numeral 55 denotes a holder supported by a terminal (40 in FIG. 2) at the end of the charging cable gas via a protective resistor 56, and this holder 55 and the adapter fitting 52 are electrically connected. 57 is a rotation stopper supported by a holder, and its tip 571 is slidably connected to the keyway 542 of the slide metal rod 54 described above. 58 is a shield metal fitting.

In FIG. 3, the sliding metal rod 54 can be moved axially by rotation of the handle 51. In FIG.

In the cable line to be subjected to the withstand voltage test according to the present invention, as shown in FIG. 4, the cable terminal end c is provided inside the case a of a gas insulated device such as a gas insulated switch.

To carry out the present invention, first, as shown in FIG. , fill with gas.

After that, by operating the handle 51, the electrical connection between the terminal part 4 of the charging cable gas and the terminal part c of the cable line b is electrically cut off, and the withstand voltage test of the test set T is performed using the DC voltage generator. This is carried out using apparatus 1. If a flash fault occurs between the terminal end portion 4 and the case 41, the gas pressure of the filled gas is increased to create a state in which this flash fault can be avoided.

After confirming that there is no internal circuit in the test set T through this test, by operating the handle 51, as shown in FIG. The cable is electrically connected, and the cable is tested for withstand voltage using the energizing set T.

In the above, if the diameter of the test case and the diameter of the equipment case are different, a spacer tube (conical cylindrical shape) for diameter adjustment may be used to connect the two cases.

As described above, according to the present invention, since the gas termination part is used as the power supply terminal part 4, it is possible to use a small and therefore lightweight power supply terminal part, and the terminal can be easily carried,
It is advantageous for work. Furthermore, the withstand voltage test of the cable line can be performed after confirming that no flash fault occurs between the gas-submerged termination section 4 and the test case 41, so that surges that inevitably occur during flash faults can be This eliminates the negative impact on cable lines due to Moreover, since the work of evacuation and gas filling in the case is completed only once, the test can be carried out in a short time, and work efficiency can be improved.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing the state during a withstand voltage test of a cable line in the present invention, Fig. 2 is an explanatory diagram showing a charging set used in the present invention, and Fig. 3 is an explanatory diagram showing the charging set used in the present invention. FIG. 4 is an explanatory diagram showing the apparatus and FIG. 4 is an explanatory diagram showing the present invention. In the figure, T is the charging set, 1 is the power source for charging, 4 is the cable gas termination for charging, 41 is the test case, a is the equipment case, b is the cable line, and c is the cable termination. .

Claims (1)

[Claims] 1. When performing a withstand voltage test on a cable line with a cable end provided inside the case of gas-filled equipment, cover the power charging end of the power charging set with a power source for the above cable end with a test case, The test case and the equipment case are airtightly connected, gas is filled in both cases after evacuation, and then the charge switching device attached to the test case is operated. After cutting off the electrical connection between the power end and the cable end, conduct a withstand voltage test of the power supply set using the power supply described above, and then, by operating the power supply switching device, Electrically connect the termination part and the cable termination part,
A withstand voltage test method for a cable line, characterized in that a withstand voltage test of the cable line is performed using the energizing set.