JPS603764B2 - oil-filled electrical equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to oil-filled electrical equipment such as oil-filled transformers and oil-filled actors, and more particularly to oil-filled electrical equipment having an improved high-voltage lead outlet structure.

In recent years, due to the deterioration of the oil situation, special high-voltage class oil-filled electrical equipment has begun to adopt a so-called oil-saving structure that saves the amount of insulating oil stored inside the tank.

For example, as shown in Fig. 1, this oil-saving structure
The lower part of the tank 1 is raised to fit the lower part of the core 2 to save the insulating oil 4 near the lower core clamp 3a, or the short side of the rectangular tank 1 is raised as shown in Fig. 2. There are devices that are formed in a semicircular shape to save insulating oil around the coil 5, and these devices also have the ground insulation dimensions around the coil 5 and the high voltage lead 6 set to values close to the maximum value. It has been downsized to save oil. By the way, in this type of oil-filled electrical equipment, the high-pressure bushing is generally not installed on the cover due to height restrictions, but is installed through a duct 7 in the center of the side of the tank 1, as shown in Figures 2 and 3. Attach the bushing pocket 8 to each phase bushing 9A, 9B, 9C.
A structure is adopted in which it is attached.

Therefore, the high voltage leads 6 led out from the coils 5 of each phase must be led out to the pushing pocket 8 on the side of the tank 1. There are various structures for guiding the high voltage lead 6 to the bushing pocket 8, but in this case, passing the high voltage lead 6 under the coil 5 means that the lower part of the tank 1 fits into the iron core 2. It is impossible because there are Therefore, the high voltage lead 6 passes through the coil 5 either on the side or above it. The structure in which the high-voltage lead 6 passes through the side of the coil 5 requires a large distance between the coil 5 and the tank 1, which eliminates the oil-saving effect, and the above distance can be reduced by providing insulation reinforcement to the high-voltage lead 6. However, the insulation reinforcement work requires a large number of man-hours and has the drawback of extremely poor workability. For this reason, a structure in which the high voltage lead 6 is passed above the coil 5 is often adopted. The high voltage leads 6 of each phase led out through the upper side of the coil 5 are further lowered to the center on the side of the tank 1, and passed through the duct 7 to the bushings 9A, 98,
9C is connected to the oil submerged side terminal 1, and is supported in the middle by supports 11 and 12 attached to the upper iron core clamp 3b and an insulating support 13 attached to each support 11 and 12. However, the above-described structure has the drawback that the space between the coil 5 and the side surface of the semicircular tank 1 through which the high-voltage lead 6 passes becomes large, and as the tank 1 becomes larger, the amount of insulating oil increases.

Further, since the high voltage lead 6 is supported as a point by the insulating support 13, it is easily shaken, and a sufficient distance for assembly is required in addition to the necessary distance between the high voltage lead 6 and the duct 7. Furthermore, since the duct 7 is connected to the side surface of the semicircular tank 1, a high degree of precision and a large number of man-hours are required when manufacturing and installing the duct 7.

In addition, in order to provide air insulation distance between the bushing pocket 8 and the upper part of the bushing 9, the mounting flange surface of the bushing 9 must be sloped. This method had the disadvantage of requiring a number of man-hours and extremely poor workability.
The present invention has been made in consideration of the above-mentioned points, and an object of the present invention is to provide an oil-filled electrical device in which the steel material can reduce the amount of insulating oil and improve assembly workability.

Embodiments of the present invention will be described below with reference to the drawings.

In FIGS. 5 and 6, the iron core 2 and the coils 5 of each phase
The contents consisting of are stored together with insulating oil 4 in a tank 21 having semicircular sides on both sides in the longitudinal direction. There are three pipes 2 at the top of the semicircular side of the tank 21.
One end of each pipe 2A, 22B, 22C is arranged horizontally and connected by welding, and each pipe 22A, 22B, 22C is connected by welding.
are arranged radially so that they are slanted downward. At the other end of each pipe 22A, 22B, 22C, there are rectangular cylindrical bushing pockets 23A, 23B arranged vertically.
23C, each pocket 23A, 23B,
Attach bushings 9A, 9B, and 9C to the top surface of 23C, respectively. The high voltage lead 16 of each phase is led out through the upper side of the coil 5 and supported by the insulating support 24 attached to the upper core clamp 3b, and is connected to each pipe 22A.
, 22B, 22C and are longer than the above-mentioned pipes. Connect the middle terminal 1 electrically. Also pipes 23A, 23B, 23C
Both end portions of the insulating tubes 25A, 25B, 25C protruding from the tank 21 are connected to each other through metal fittings 3 and supports 31 fixed near the pipe connection portions of the side of the tank 21 and the pipe connection portions of each bushing pocket 23A, 23B, 23C. and support each other. Further, a shield ring 32 is provided on the inner surface of the bridge edge of each connection portion to alleviate the electric field. Each bushing pocket 2
3A, 23B, 23C and between each pushing pocket 23A, 23B, 23 and the side surface of the tank 21 are connected by reinforcing members 28 arranged horizontally to connect each pushing pocket 23A, 23B, 23C to the tank 21. It is mechanically fixed integrally to 21. With this configuration, the high voltage leads 6 of each phase are connected to the pipes 22A, 22B, 22 on the side of the tank 21, which are provided at approximately the same height from the top of the coil 5.
C, the distance between the coil 5 and the tank 21 can be reduced, the tank 21 can be made smaller, and the amount of insulating oil can be reduced.

Furthermore, since the high voltage lead 16 is held within the insulating tubes 25A, 25B, and 25C, there is little positional fluctuation, and the insulating tubes 25A, 25B, and 25C are also fixed to the tank 21 and the bushing pockets 23A, 23B, and 23C. There is almost no positional fluctuation. Therefore, each pipe 22A, 22B,
The positional deviation of the high voltage lead 16 within 22C can be suppressed to about a few degrees. On the other hand, in order for the high voltage lead 16 to cause dielectric breakdown to the pipes 22A, 22B, 22C, the insulating cylinder 2
5A, 25B, 25C or insulating tube 2
There are only two ways to break from both ends of 5A, 25B, and 25C, but insulating tubes generally have high penetration breakdown strength,
Moreover, in the present invention, both ends of the insulating cylinders 25A, 25B, 25C are made to protrude from the pipes 22A, 228, 22C, and the high voltage lead 16 is made to protrude away from the earth electrode of the pipe, tank, etc., so that the insulating cylinders 25A, 25
It is also possible to prevent creepage failure at both end portions of B and 25C.

Therefore, the dielectric breakdown strength of the high voltage lead 16 with respect to the pipes 22A, 22B, and 22C becomes extremely high. Furthermore, for the pushing pockets 23A, 23B, and 23C used in the present invention, commercially available thick square pipes with an elevation angle of about several hundred degrees can be used. There is no need to manufacture it by welding with a steep slope.

Therefore, material costs and manufacturing man-hours can be reduced.・Furthermore, as shown in Figure 7, the conventional bushing pocket
In order to ensure that the bushings 9A, 9B, and 9C are mutually protected from atomization, a beveled portion must be provided at both ends of the upper surface of the bushing pocket 8, so that each phase bushing 9A. The distance between the mounting parts of bushings 9B and 9C had to be larger than the distance between the oil-inside terminals 10 of each phase bushing 9A, 9B, and 9C, whereas the bushing pockets 23A, 23B, and 23C is the 8th
As shown in the figure, the size may be such that the necessary insulation distance between the oil-submerged side terminals of one bushing 9A, 9B, or 9C is secured.

Therefore, the amount of insulating oil in the bushing pockets 24A, 24B, 24C is smaller than that in conventional bushing pockets. Furthermore, butching pockets 23A, 23B,
Pipe 22A, 2 connecting 23C and the side of tank 21
Since 2B and 22C are arranged radially from the center of the side surface of the semicircular tank 21, the material can be easily cut out, the connection area is small, and high precision is not required, making the connection work extremely easy.

Incidentally, even if the side surface of the tank 21 is flat, the same effect as in the above embodiment can be achieved in other parts, except that the work of connecting the tank side surface and the pipe is slightly complicated.

Furthermore, round pipes can be used instead of square pipes for the butting pockets 24A, 24B, and 24C. As explained above, in the oil-filled electrical equipment according to the present invention, high voltage leads for each phase are provided for each phase, and an insulating tube is installed in the pipe that is inclined downward from the upper side of the tank and is arranged radially. A bushing pocket is attached to the tip of each pipe, a bushing is attached to each bushing pocket, and the high voltage lead is connected to the terminal on the oil side of this bushing, so the amount of steel material and insulating oil can be reduced. Assembly workability can be improved.

[Brief explanation of drawings]

Figure 1 is a cross-sectional side view of a conventional oil-filled electrical equipment, Figure 2 is a plan view of a subordinate oil-filled electrical equipment, and Figures 3 and 4 are high-voltage IJ-drawer outlets of conventional oil-filled electrical equipment. FIGS. 5 and 6 are a partially sectional plan view and side view of an embodiment of the oil-filled electrical equipment according to the present invention; FIG. 7 is a conceptual diagram showing a conventional bushing pocket, and FIG. 8 is a conceptual diagram of a bushing pocket in an oil-filled electrical device of the present invention. 2... Iron core, 4... Insulating oil, 5...
... Coil, 9A, 9B, 9C ... Bushing, 10 ... Oil inside terminal, 21 ... Tank, 22A, 22B, 22C ... Pipe, 23A, 238
, 23C...Butching pocket, 25A, 25B, 2
5C...Insulating tube. Figure 8 Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

Claims (1)

[Claims] 1. An iron core and each phase coil wound around this iron core are stored in a tank together with insulating oil, and multiple coils are arranged at horizontal intervals and in a radial direction on the upper part of the short side of this tank. Connect one end of the pipes, tilt these pipes downward, attach a bushing pocket to the tip, attach a bushing to the bushing pocket, and connect the high voltage leads drawn out from the coils of each phase to the coils. An oil-filled electrical device which is led out from the upper part of the bushing, inserted into the pipe via an insulating cylinder, and connected to the oil-inside terminal of the bushing.