JPS59631Y2 - Gas insulated current transformer polarity test equipment - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a polarity testing device for a gas insulated current transformer that is applied to downsized electrical equipment using an insulating gas such as SF6 gas.

Conventionally, for example, as shown in FIG.
In , the main conductor 2 of the bus bar A is used as the primary winding, one end is welded to the inner jacket 5 and the inner jacket 5 has a flange 4 that is airtightly connected to the outer jacket flange 3 of the bus bar A, and the other end is welded to the inner jacket 5. has a flange 7 hermetically connected to the outer sheath flange 6 of the bus bar A or other electrical equipment B, and an outer sheath 8 formed to cover the outer periphery of the inner sheath 5 and the inner sheath 5. The secondary winding 9 is insulated from the inner jacket 8 and 5 in the created space.
The outer sheath 8 is provided with a sealed insulated terminal 11 to which a winding 10 led out from the secondary winding 9 is connected.

The polarity direction of the secondary winding 9 of such a current transformer 1 is
In particular, as the number of secondary windings 9 increases, if there is a difference in polarity direction, the function as a current transformer will be impaired.

By the way, when performing the above-mentioned polarity test of a current transformer, as shown in Fig. 2, grounding devices 12 and 13 are installed on the sealed bus bar A and the electrical equipment B on both sides of the current transformer 1, respectively. By connecting the grounding devices 12 and 13 to the main conductor 2 in a state where the main conductor 2 is not charged, and passing a direct current through the circuit of the grounding device 12 - the main conductor 2 - the grounding device 13, the secondary winding 9 is The polarity of the secondary winding 9 is tested from the terminal 11 by the generated back electromotive force.

Also, depending on the arrangement of gas insulated equipment, the grounding device 12
, 13, care must be taken when assembling the secondary winding 9, and confirmation testing is difficult after assembling the secondary winding 9, making the reliability of the current transformer 1 extremely low. It will be low.

Further, in the configuration in which the above-mentioned grounding devices 12 and 13 are arranged, the number of devices increases, the space of the entire device becomes large, and the device becomes expensive.

Therefore, the present invention was developed in view of the above circumstances, and it is a gas-insulated transformer that allows easy and reliable polarity testing of the secondary winding of a current transformer and that can fully demonstrate its performance as a current transformer. The purpose of the present invention is to provide a device for testing the polarity of water vessels.

The present invention will be explained below with reference to an embodiment shown in FIG.

In Fig. 3, a current transformer 1 installed in the middle of a sealed bus A filled with SF6 gas or between this bus A and electrical equipment B has the main conductor 2 of the bus A as the primary winding, and the outside of the bus A. An inner sheath 5 having a flange 4 hermetically connected to the flange 3, and a flange 7 hermetically connected to the busbar A or the outer sheath flange 6 of the electrical equipment B at the other end, with one end welded to the inner sheath 5. and an outer sheath 8 formed to cover the outer periphery of the inner sheath 5, and a secondary winding insulated from the inner sheaths 5 and 8 in the space created by the inner sheath 5 and the outer sheath 8. 9 is placed.

An insulated wire 12 for polarity testing is arranged between the opposing surfaces of the secondary winding 9 and the inner sheath 5, and one end of this insulated wire 12 is electrically connected to the inner sheath 5, and the other end is connected to the outer sheath 8. It is connected to a sealed insulated terminal 11 provided.

A winding 10 led out from the secondary winding 9 is also connected to the sealed insulated terminal 11 .

On the other hand, the outer sheath 8 is provided with a current-carrying terminal 14 .

In such a current transformer 1, the polarity test of the secondary winding 9 is performed while the main conductor 2 of the sealed bus bar A is not charged, and the direct current is connected to the sealed insulated terminal 11 - insulated wire 12 - inner sheath 5 - The polarity of the secondary winding 9 can be tested from the sealed insulated terminal 11 by the back electromotive force generated in the secondary winding 9 by flowing the voltage through the circuit between the jacket 8 and the terminal 14 .

According to the polarity testing device for gas insulated current transformers of the present invention having the above-described configuration, there is no need to provide equipment such as a grounding device as in the past, and the space of the device as a whole can be reduced, and it is also inexpensive. .

In addition, the polarity of the secondary winding does not depend on the precautions taken during assembly, and the polarity test can be easily performed even after assembly, and the reliability of the current transformer is extremely high even when the number of secondary windings increases. Become.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a conventional gas-insulated current transformer, Figure 2 is an explanatory diagram of the current transformer shown in Figure 1 with a grounding device installed, and Figure 3 is an illustration of the current transformer of the present invention. FIG. 3 is a cross-sectional view showing one embodiment. A... Sealed busbar, B... Electrical equipment, 1... Current transformer, 2... Main conductor (primary winding), 3.4.6, 7...
Flange, 5... Inner cover, 8... Outer cover, 9... Secondary winding, 10... Winding wire, 11... Sealed insulated terminal, 12
．． 13...Grounding device, 12...Insulated wire, 14...
・Electricity terminal.

Claims (1)

[Scope of utility model registration request] The primary winding is a conductor of a gas-insulated hermetically sealed bus bar, an inner sheath having a flange airtightly connected to an outer sheath flange of the bus bar, and an inner sheath having one end fixed to the inner sheath and the other end of the bus bar. an outer sheath airtightly connected to an outer sheath flange of the electrical equipment and formed to cover the outer periphery of the inner sheath; and two parts arranged in a space formed by the inner sheath and the outer sheath insulated from the inner sheath. an insulated wire for polarity testing between the secondary winding and the opposing surfaces of the inner sheath, one end of which is connected to the inner sheath, and the other end of which is a sealed insulated wire provided on the outer sheath. A polarity test device for a gas insulated current transformer, wherein an insulated wire for polarity test connected to a terminal is arranged, and a polarity test of the secondary winding is performed by passing a current through the insulated wire.