JP2686929B2 - Test method for cable lines directly connected to both ends - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a method for testing a cable line directly connected to a both-end device in which a test case can be omitted. [Technical background of the invention and its problems] In recent years, from the viewpoint of downsizing the site and improving reliability of power transmission, GI
S (Gas Insulatad Swith gear) equipment is widely used. For this reason, there are many cable devices in which both ends of the underground power transmission line are connected to the GIS device and one end is directly connected to the GIS device and the other end is directly connected to the transformer. However, in such a cable line whose both ends are directly connected to the GIS equipment, since there is no exposed part in the air, it is easy to perform DC withstand voltage test and leak current measurement like a so-called ordinary cable line with an air termination. There was a problem that the test or the characteristic test such as the corona measurement test could not be performed. Therefore, conventionally, for example, as shown in FIG. 5, a test case 4 having a built-in protective resistor 2 and a bushing 3 is temporarily connected to the device case 1, and the bushing 3 in the test case 4 is connected to other parts. It is practiced to connect one end of a lead wire 5 for voltage application having an air terminal portion (not shown) at the end and to apply a predetermined test voltage to the air terminal portion of the power lead wire. However, in the test method of such a configuration, the equipment for voltage application becomes large, and its handling is not easy.
There was a difficulty that a large space for the electric test should be taken. [Object of the Invention] The present invention has been made in order to solve the above-mentioned conventional problems, and it is possible to omit a test case and perform a test of a cable line directly connected to both ends of a device capable of performing a voltage test even in a narrow space. It is intended to provide a method. [Outline of the Invention] According to the present invention, a bushing is attached to one device case of a cable line directly connected to a device at both ends in a hermetic manner such that a tip of a conductor extraction electrode forming the bushing is located in the device case. The other end of the power-supply lead wire having a power-supply section is connected to the bushing, and in the test method of a cable line at both ends of a device for applying a test voltage to the power-supply section of the power-supply lead wire, the bushing is , A cylindrical shield electrode having a contactor on its inner circumference, a conductor extraction electrode set up on the outer circumference of the shield electrode so as to be orthogonal to the axis thereof, and an outside of the conductor extraction electrode and the shield electrode. It is composed of a tip of the conductor leading electrode and a mold insulator that covers the shield electrode except one opening, and is attached to the contact in the shield electrode at the tip of the conductor at the other end of the lead wire for voltage application. Done It is characterized by connecting plugs that are plugged in. Hereinafter, an embodiment of the present invention shown in the drawings will be described. FIG. 1 is a schematic view showing an embodiment of the present invention, and FIG. 2 is a partial sectional view of a bushing used in the present invention. As shown in FIGS. 1 and 2, a bushing 9 is attached to one device case 7 of the cable line 6 directly connected to both ends of the device.
The tip 12 of the conductor lead-out electrode 11 is airtightly mounted so as to be located inside the equipment case 7, and the bushing 9 is connected to the other end of the power supply lead wire 10 having the power supply section 8 at one end to The point that a test voltage is applied to the voltage applying section 8 of the electrical lead wire 10 is the same as the conventional test method. In the present invention, the bushing 9 having no conventional test case is airtightly mounted on the device case 7, and the other end of the power supply lead wire 10 is plug-in connected to the bushing 9. As shown in FIG. 2, the bushing 9 according to the present invention includes a cylindrical shield electrode 13 and a rod-shaped conductor lead-out electrode 11 which is erected on the outer periphery of the shield electrode 13 so as to be substantially orthogonal to the axis.
And the outside of the conductor extraction electrode 11 and the shield electrode 13 is provided with one opening of the tip 12 of the conductor extraction electrode 11 and the shield electrode 13.
Mold insulator such as epoxy mold that covers except 14 15
It is composed of An annular groove 16 is provided on the inner circumference of the shield electrode 13, and an annular contactor 17 that expands and contracts in the radial direction is provided in the groove 16. FIG. 3 shows an enlarged view of a main part of the other end of the lead wire 10 for charging. In the figure, the conductor at the other end of the lead wire 10 for charging
A plug 18 capable of being plug-in connected to the contact 17 is attached to the tip end of the contact 17, and a stress cone 20 is attached to the outer periphery of the insulator 19. The other end of the charging lead wire 10 having such a configuration is
The plug 18 is inserted into the insertion port 21 of the bushing 9, and the plug 18 is plug-in connected to the contactor 17 in the shield electrode 13. Then
By applying a predetermined test voltage to the power applying section 8 of the power applying lead wire 10, it is possible to perform a DC withstanding voltage test or the like of the cable line directly connected to the both end devices. In addition, the lead wire for voltage application 10
Protective cylinder with a stress cone compression device 22 built in at the other end
23 is mounted, and the flange 24 of the protective cylinder 23 is fixed to the peripheral wall of the insertion port 21 of the bushing 9 to provide a stress cone.
20 has a proper compression force. FIG. 4 shows an embodiment in which the bushing 9'has a protective resistance 25 built therein. In this embodiment, a rod-shaped internal electrode 26 is erected on the outer periphery of the shield electrode 13, and a plurality of cylindrical electrodes are provided between the internal electrode 26 and the exposed electrode 27 that is exposed in the device case 7. Individual protection resistors 25 are provided. Reference numeral 28 in the drawing denotes a conductive spring mounted between the exposed electrode 27 and the protective resistance 25. In the embodiment shown in FIG. 4, since it is not necessary to attach a protective resistance to the tip of the bushing 9 ', it is possible to quickly carry out a withstand voltage test or the like in the field, and a space required for the test. There is an advantage that can be reduced. In the figure, reference numeral 29 is a connecting rod, 30 is a terminal portion of a device DC cable line as a device under test, and 31 is a bushing 9, 9 '.
In the figure, 32 is a pre-molded flange, 32 is a semiconductive layer of the lead wire for voltage application, 33 is the same shielding layer, 34 is the same sheath, and 35 is a seal. [Effects of the Invention] As described above, according to the method for testing a cable line directly connected to both ends of the device according to the present invention, the conventionally used test case is not required, so that the space for performing the test can be reduced. As a result, there is an advantage that the building itself that houses the GIS equipment can be made compact.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing an embodiment of the test method of the present invention,
FIG. 2 is a partial sectional view of a bushing used in the present invention, FIG. 3 is an enlarged sectional view of the other end of the lead wire for charging, and FIG.
FIG. 5 is a partially sectional view showing another embodiment of the bushing, and FIG. 5 is a partially omitted schematic view of a conventional test method. 6 ... Cable line directly connected to both ends equipment 7 ... Equipment case 8 ... Power supply section 9, 9 '... Bushing 10 ... Power supply lead wire 11 ... Conductor lead electrode 13 ... Shielding electrode 17 ... Contact 18 ... Plug

Claims (1)

(57) [Claims] On one device case of the cable line directly connected to both ends device,
The bushing is attached airtightly so that the tip of the conductor extraction electrode that constitutes the bushing is located in the device case, and the other end of the power supply lead wire having a power supply unit at one end is connected to the bushing. In a test method for a cable line directly connected to a device at both ends, in which a test voltage is applied to a voltage applying section of the power applying lead wire, the bushing has a cylindrical shield electrode having a contactor on its inner circumference, and the shield electrode. A conductor lead-out electrode erected on the outer periphery of the conductor so as to be orthogonal to its axis, and a mold insulator covering the conductor lead-out electrode and the outside of the shield electrode except the tip of the conductor lead-out electrode and one opening of the shield electrode. And a plug attached to the conductor tip of the other end of the lead wire for voltage application is plug-in connected to the contact in the shield electrode. Test method. 2. The conductor extraction electrode is a rod-shaped internal electrode erected on the outer periphery of the shield electrode, and an exposed electrode exposed in the device case,
The test method for a cable line directly connected to a double-ended device according to claim 1, characterized in that the test method comprises a protective resistance electrically connected between these electrodes.