JPS61268012A - Oil-filled electric equipment for high voltage - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention utilizes the deformation of the case due to the gas generated in the event of an internal failure to cut the conductive part of the safety device to interrupt the current. It concerns the improvement of equipment.

Conventional Technology Conventionally, in oil-filled electrical equipment such as oil-filled capacitors, when an internal failure occurs, the oil decomposes due to the generation of a heating arc in the failed part, generating gas and increasing the internal pressure of the case. There was a risk of an explosion, oil gushing, and a major accident.

As one method for preventing this, a security device as shown in FIG. 3 has been used.

Figure 3 shows an example of an oil-filled capacitor, where 1 is a case made of steel plate, 2 is a drawer bushing, 3 is a capacitor body, 4 is a safety device, 41 is a conductive part of the safety device 4, and 5 is a drawer. A lead wire is connected from the bushing 2 to the capacitor body 3 via the safety device 4, 6 is an insulating oil, and 7 is a gas.

FIG. 3(a) shows a normal state, but the capacitor body 3
When a failure occurs, the internal pressure increases due to the generated gas and the case 1 is deformed, as shown in FIG. This will prevent the accident from progressing.

However, oil-filled electrical equipment such as oil-filled capacitors that use such safety devices have conventionally been mostly applied to the low voltage range of 200V or 400V class.
As shown in Figures (0) or (8), even if the conductive part of the safety device is exposed to oil or gas, the distance between the disconnected conductive part poles is sufficient for the working voltage, so the safety After operation of the device, there was no re-ignition between the conductive electrodes.

Problems to be Solved by the Invention However, in the case of a high voltage range where the operating voltage is even higher, it becomes very difficult to interrupt the leading phase current, especially in the case of oil-immersed capacitors, and the safety device may not operate normally. Re-ignition of the electrically conductive part that had been cut off occurred due to the position of the oil level, which had dropped due to the bulge in the case due to gas generation. That is, such re-ignition occurs when the electrically conductive part of the safety device is exposed to gas present above the oil level, as in the case of FIG. 3(c).

Means and Effects for Solving the Problems The present invention aims to provide a high voltage oil-filled electrical device that eliminates the above-mentioned drawbacks.

In other words, a re-ignition in the safety device not only impairs the safety function, but also has the potential to lead to an accident with secondary disasters, so it is necessary to have a highly functional structure and safety device to suppress such re-ignition. Required for working voltages in the voltage range.

For this reason, we investigated the relationship between gas generation in areas that had not been given much attention in the past, □ rise in case internal pressure - case bulge, and □ oil level drop in terms of case dimensions and case material thickness. The distance between the poles of the cutting conductive part was investigated, and the mounting position of the safety device was determined. In other words, for example, if the case material is too thick, it will not be possible to obtain the specified displacement due to the case bulge, and the distance between the poles of the cutting conductive part after operation will be insufficient even in oil, resulting in the possibility of re-ignition. ,
On the other hand, if the thickness of the case material is too thin, even if sufficient displacement is obtained due to the bulge of the case, the cut conductive part will be exposed to the gas on the oil surface, creating the possibility of re-ignition.

Therefore, for the normal operation of the safety device in the high voltage range, there naturally exists a "cooperation area" consisting of the structure of the case and the structure and function of the safety device, and within this cooperation area, the safety device It is necessary to choose the mounting position. That is, as a result, the mounting position of the safety device is not limited to the case where it is mounted on the top of the capacitor body as shown in FIG. When the capacitor body is divided into two parts, an upper stage and a lower stage, and the capacitor is attached to the middle part thereof, the capacitor body may be attached to the lower part of the capacitor body, that is, the bottom of the case, as shown in FIG. 1 (ff). The direction in which the capacitor is used, for example, when installing it upright as shown in Figure 2 (A), when installing it upside down as shown in Figure 2 (B), or laying it sideways as shown in Figure 2 (C). It is necessary to set the mounting position of the safety device in consideration of the case where it will be installed in the direction of the safety device.

Figure 1 shows an example of an oil-immersed capacitor, and as in Figure 3, 1 is a case made of a steel plate, 2 is a drawer bushing, 3 is a capacitor body, 4 is a safety device, and 41 is the conductor of the safety device 4. 5 is a lead wire connected from the drawer bushing 2 to the capacitor body 3 via the safety device 4, 6 is an insulating oil, and 7 is a gas.

Effects of the Invention As described above, the high-voltage oil-filled electrical equipment of the present invention has its case, safety device, and other constituent materials and parts placed in predetermined positions so that the conductive parts of the safety device are always submerged in oil. By arranging this arrangement, a highly safe safety function in a high voltage range without re-ignition can be obtained, which is of great industrial and practical value.

[Brief explanation of the drawing]

Figure 1 is an explanatory cross-sectional view of the high-voltage oil-filled capacitor of the present invention when the built-in safety device is activated due to an abnormality.
(a) is a case where the safety device is installed in the middle between the upper and lower capacitor bodies, (b) is a case where the security device is installed at the bottom of the case, and Figure 2 is a side view of an example of the direction in which the capacitor is used. (a) is when installed in an upright direction, (o) is when installed in an inverted direction, (c) is when installed in a sideways direction. Figure 3 is for explaining a conventional oil-filled capacitor equipped with a safety device. In the cross-sectional view, (A) is normal, (TI) and (
C) is a case where the safety device is activated due to an abnormality. 1: Case 2: Drawer bushing 3: Capacitor body 4: Safety device 41: Conductive part 5: Lead wire 6: Insulating oil 7: Gas

Claims (1)

[Claims] Utilizing the deformation of the case due to gas generated during internal failure,
In high-voltage oil-filled electrical equipment in which the electrical current is cut off by cutting the conductive part of the safety device, each constituent material and component is placed in a predetermined position so that the conductive part is always submerged in oil even after the safety device is activated. High-voltage oil-filled electrical equipment characterized by being placed in.