JP2010197159A - Withstand voltage test device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a withstand voltage test device enabling downsizing of the entire configuration and facilitating connection of a lead wire for applying a voltage to an electric component in a pressure container. <P>SOLUTION: The withstand voltage test device includes: a tubular insulation pressure container 1; an upper cover plate 3 hermetically provided on an upper opening of the insulation pressure container 1; an extendable metal fitting 5 which is freely extendable and has one end fixed to the upper cover plate 3; an electrode 6 for applying a voltage fixed to the other end of the extendable metal fitting 5 and contacting a main circuit of an electric component 13; a mounting electrode 12 hermetically provided on a lower opening of the insulation pressure container 1, mounted on the electric component 13 and having a ground potential; and a filling means 20 for filling the insulation pressure container 1 with an insulation media. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a withstand voltage test apparatus for verifying insulation characteristics of electrical components used in electric power equipment.

Vacuum valves having a pair of contactable contacts that are used in power devices such as vacuum circuit breakers have been reduced in size due to the excellent insulating properties of vacuum. However, in the withstand voltage test for grasping the limit characteristics such as between contacts, the external insulation is weaker than the internal insulation, so the vacuum valve is placed in an insulating medium having a high dielectric strength such as SF ₆ gas or compressed air. The external insulation was reinforced (see, for example, Patent Document 1).

JP 2001-194409 A (pages 2 and 3, FIG. 1)

  The above conventional withstand voltage test apparatus has the following problems. An insulating medium that reinforces the external insulation is sealed in a steel pressure tank, and a bushing for applying voltage is attached to the outer wall of the pressure tank. The bushing has a large body diameter, a long axial direction, and a remarkably high dielectric strength so that the breakdown voltage characteristics as well as the withstand voltage characteristics of electric parts such as vacuum valves can be verified. Yes.

  For this reason, the withstand voltage test apparatus equipped with a pressure tank and a bushing has a large overall shape and is a heavy object. Moreover, installing an electrical component in a closed space such as a pressure tank and connecting the electrical component and the bushing has been a difficult operation because the space in the pressure tank is small.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a withstand voltage test apparatus that can reduce the overall shape and facilitate connection work for applying a voltage.

  In order to achieve the above object, a withstand voltage test apparatus according to the present invention includes a cylindrical insulated pressure vessel, an upper lid plate hermetically provided in an upper opening of the insulated pressure vessel, and one of the upper lid plate. A telescopic metal fitting with a fixed end, a voltage application electrode that is fixed to the other end of the metal fitting and in contact with the main circuit of the electrical component, and a lower opening of the insulating pressure vessel And a mounting electrode having a ground potential for mounting the electric component, and a sealing means for sealing an insulating medium in the insulating pressure vessel.

  According to the present invention, since the insulating pressure vessel in which the insulating medium is sealed at a predetermined pressure is used and the electrical component is connected with the expansion bracket, the connection work to the electrical component can be facilitated, The overall shape of the voltage test apparatus can be reduced.

Sectional drawing which shows the structure of the withstand voltage test apparatus which concerns on the Example of this invention. The figure explaining the assembly method of the withstand voltage test apparatus which concerns on the Example of this invention. The figure explaining the enclosure pressure of the withstand voltage test apparatus which concerns on the Example of this invention.

  In the present invention, an insulating pressure vessel that has an insulating property and encloses an insulating medium at a predetermined pressure is used for housing electrical components, and a voltage application electrode that can be expanded and contracted is provided to connect the electrical components. Hereinafter, details will be described with reference to examples.

  A withstand voltage test apparatus according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view showing a configuration of a withstand voltage test apparatus according to an embodiment of the present invention, FIG. 2 is a diagram illustrating an assembling method of the withstand voltage test apparatus according to an embodiment of the present invention, and FIG. It is a figure explaining the enclosure pressure of the withstand voltage test apparatus which concerns on the Example of invention.

  As shown in FIG. 1, an upper cover plate 3 is airtightly fixed with bolts 4 through an O-ring 2 in an upper opening of a cylindrical insulating pressure vessel 1 made of FRP such as epoxy resin. In the insulating pressure vessel 1 of the upper lid 3, one end of a rhomboid expansion metal fitting 5 that is extendable in the illustrated vertical direction, that is, the axial direction of the insulating pressure vessel 1 is fixed. At the other end, a voltage applying electrode 6 having a weight enough to extend the expansion metal fitting 5 downward is fixed. One end of a voltage application lead wire 7 is connected to the voltage application electrode 6, and the other end is connected to a voltage application terminal 8 provided on the upper cover plate 3.

  The lower opening of the insulating pressure vessel 1 is hermetically fixed to the gantry 10 with bolts 11 via the O-ring 9. In the insulating pressure vessel 1 of the gantry 10, a placement electrode 12 having a ground potential is provided. The mounting electrode 12 has a concave central portion so that the movable side of the vacuum valve 13 can be easily mounted. The fixed side of the vacuum valve 13 is contact-connected by the weight of the voltage application electrode 6 and the extendable metal fitting 5.

  A viewing window 14 made of a transparent material such as an acrylic plate is provided on one side surface of the intermediate portion of the insulating pressure vessel 1 and sealed with an adhesive layer 15 made of an insulating material. On the other side, the outer periphery of the cylindrical intermediate electrode 16 having a hollow portion is sealed with an adhesive layer 17 made of an insulating material. An intermediate potential measuring rod 19 is provided in the hollow portion of the intermediate electrode 16 so as to move in an airtight manner in the left-right direction in the figure via an O-ring 18. The tip of the intermediate potential measuring rod 19 can come into contact with the intermediate potential fitting 13 a of the vacuum valve 13.

  The gantry 10 is provided with an enclosing tube 20 that encloses an insulating medium such as dry air in the insulating pressure vessel 1. Although not shown, a pressure gauge for measuring the pressure in the insulating pressure vessel 1 and a safety valve for releasing the pressure when the pressure rises above a predetermined value are provided. These safety valves, pressure gauges, and the like including the sealed tube 20 can be attached to the side surface of the insulating pressure vessel 1, the upper cover plate 3, and the like.

  Next, the procedure for setting the vacuum valve 13 in the insulating pressure vessel 1 will be described with reference to FIGS.

  As shown in FIG. 2, the bolt 11 is removed, and the insulating pressure vessel 1 is lifted by a crane (not shown) to be separated from the gantry 10. First, the main circuit on the movable side of the vacuum valve 13 is placed on the placement electrode 12 in the downward direction. The vacuum valve 13 brings the pair of contacts into a predetermined state of closing or opening. In this state, the extendable metal fitting 5 extends downward due to the weight of the voltage application electrode 6.

  Next, the insulating pressure vessel 1 is gradually lowered, the end is brought into contact with the gantry 10, and fixed with the bolt 11 through the O-ring 9. At this time, the extension metal fitting 5 contracts as the voltage application electrode 6 contacts the main circuit on the fixed side of the vacuum valve 13. The fixed side and the movable side of the vacuum valve 13 are in contact with the electrodes 6 and 12 with a predetermined pressure.

Next, a cylinder of dry air (not shown) is connected to the sealing tube 20 to fill the insulating pressure vessel 1 with dry air (insulating medium sealing means). The sealing pressure is, for example, 0.25 MPa as shown in FIG. With this pressure, the withstand voltage is about three times the atmospheric pressure, which is about the same as the atmospheric pressure of SF ₆ gas. That is, the external insulation of the vacuum valve 13 can be reinforced to the same extent as the SF ₆ gas insulation, and the internal insulation can be verified. The insulating medium to be sealed may be nitrogen gas.

  If the tip of the intermediate potential measuring rod 19 is brought into contact with the intermediate potential fitting 13a of the vacuum valve 13 and an electrometer is connected to the outside, the potential of the intermediate potential fitting 13a can be measured. Furthermore, a potential is applied to the intermediate potential fitting 13a, and the appearance of the vacuum valve 13 can be observed. The contact between the intermediate potential measuring rod 19 and the intermediate potential fitting 13a can be confirmed through the observation window 14. In addition, what is necessary is just to exhaust the dry air in the insulated pressure vessel 1 and to remove the volt | bolt 11 when a series of insulation verification is complete | finished.

  For these reasons, the voltage applied from the voltage application terminal 8 is shared by the creeping surface of the insulating pressure vessel 1 in the axial direction, so that a bushing for applying a voltage as in the related art becomes unnecessary. Moreover, since the insulating insulated pressure vessel 1 is used, weight reduction can be achieved compared with conventional steel. In addition, the voltage application electrode 6 connected to the voltage application lead wire 7 and the expansion / contraction metal fitting 5 connect the fixed side and the movable side of the vacuum valve 13 to each other with a predetermined pressure. There is no need to reconnect the voltage applying lead wire 7. Furthermore, since the voltage application electrode 6 expands and contracts in the vertical direction, it can be easily applied to the vacuum valves 13 having different axial lengths.

  According to the withstand voltage test apparatus of the above embodiment, the voltage application electrode 6 that can be expanded and contracted in the vertical direction is formed by connecting the voltage application lead wire 7 to the upper opening of the insulating pressure vessel 1 that encloses the pressurized dry air. Since the mounting electrode 12 having the ground potential is provided in the lower opening and the grounding potential is mounted, the connection of the voltage applying lead wire 7 to the vacuum valve 13 can be facilitated. Further, the applied voltage can be shared by the creeping surface of the insulating pressure vessel 1 in the axial direction, and the overall shape can be reduced in size and weight.

  In the above-described embodiment, the DUT has been described using the vacuum valve 13. However, the insulation used in the power equipment is insulated, and even in cast products such as insulating spacers, insulation verification such as internal partial discharge can be performed. . Here, the vacuum valve 13 and the cast product are referred to as electric parts such as power equipment.

  Further, if an observation window is provided in the upper lid plate 3, it is possible to perform daylighting from the upper portion, and it is possible to easily check the electrical components in the insulating pressure vessel 1. The observation window of the upper cover plate 3 and the observation window 14 on one side are referred to as daylighting means into the insulating pressure vessel 1.

DESCRIPTION OF SYMBOLS 1 Insulation pressure vessel 2, 9, 18 O-ring 3 Upper cover plate 4, 11 Bolt 5 Expansion metal fitting 6 Voltage application electrode 7 Voltage application lead wire 8 Voltage application terminal 10 Base 12 Mounting electrode 13 Vacuum valve 13a Intermediate potential Metal fitting 14 Peep window 15, 17 Adhesive layer 16 Intermediate electrode 19 Intermediate potential measuring rod 20 Encapsulated tube

Claims (4)

A cylindrical insulated pressure vessel;
An upper lid plate hermetically provided in the upper opening of the insulating pressure vessel;
A telescopic metal fitting with one end fixed to the upper lid plate;
A voltage application electrode that is fixed to the other end of the expansion bracket and is in contact with the main circuit of the electrical component;
A grounding electrode placed on the lower opening of the insulating pressure vessel, and a grounding potential electrode on which the electrical component is placed;
A withstand voltage test apparatus comprising: a sealing means for sealing an insulating medium in the insulating pressure vessel.   The withstand voltage test apparatus according to claim 1, wherein the electrical component is a vacuum valve having a pair of contact points that can be separated from each other.   The withstand voltage test apparatus according to claim 1 or 2, wherein an intermediate potential measuring rod that contacts an intermediate electrode fitting of the electrical component is provided on one side surface of the insulating pressure vessel.   The withstand voltage test apparatus according to any one of claims 1 to 3, wherein a daylighting means is provided on at least one side surface of the insulating pressure vessel.

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