JPH0376568B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to superconducting power energy storage devices.

[Technical Background of the Invention] In a superconducting power energy storage device (FIG. 4), cryogenic liquid helium is used for superconductivity. In order to maintain a low temperature state or to minimize the loss of stored energy due to heat intrusion into the storage device from the outside, vacuum insulation (combined with a thermal shield and multi-layer insulation) will be used, and solenoid , or the main parts of a superconducting coil device such as a toroidal type.
It will be housed in a vacuum container.

Vacuum containers have normal airtightness.
If it is 10 ^-3 Torr l/s, a large exhaust system is required and high airtightness is required, so a helium leak test must be conducted to confirm a high degree of airtightness before operation. become.
For specific measures to confirm this airtightness, please refer to
There is no mention in published literature or books yet.
Considering the methods practiced elsewhere (methods that do not use large quantities of expensive helium gas), it is necessary to have access to the inside and outside surfaces of the vacuum vessel.

On the other hand, to deal with the large electromagnetic force that acts on the coil in the superconducting state, devices such as superconducting coils are installed in underground cavities, and the surrounding strong rock (such as granite)
A method of supporting the structure by using the structure has been considered from the viewpoint of economical efficiency of the device.

Providing a vacuum container that covers the required space for superconducting coils, etc. in an underground cavity, and providing a space for airtightness inspection between the vacuum container and the cavity wall on the back side is a method of excavating the underground cavity. The cross section becomes large and becomes extremely uneconomical.

The purpose of the present invention was made in view of the above circumstances, and it is an object of the present invention to solve the problems of the prior art by simple and rational means, and to provide a structure in which airtightness can be confirmed only from the inner surface of the vacuum container. The aim is to reduce the cross section of the cavity excavated to the necessary minimum and increase the economic efficiency of the equipment.

[Means for Solving the Problems] The structure of the present invention, which solves the problems of the prior art, includes a support member having a frame-like structure perpendicular to the longitudinal axis of the cavity, which is installed on the inner wall surface of a cavity excavated in the rock. A vacuum vessel A is constructed by fixing at intervals and welding the edges of pressure plates that resist vacuum pressure between the surfaces of the support members, and inside the vacuum vessel A, there is a plate surrounded by a thermal shield. In a superconducting power energy storage device equipped with a helium container, an air passage for airtightness inspection including a weld line between the support member and the edge of the pressure plate is formed on the surface of the support member, and an air passage is formed on the inner side of the air passage. Small holes for helium filling or vacuum suction are provided at arbitrary locations on the part.

[Example] Embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a cross-sectional view of a part of the superconducting power energy storage device, FIG. 2 is an enlarged sectional view of the main part of the vacuum container, and FIG. 3 is an enlarged sectional view of the same embodiment.

In the figure, 1 is a bedrock, and 2 is a cavity excavated in the bedrock 1. Support members 4 are attached to the inner wall surface of the cavity 2 by lock bottles 3 at appropriate intervals, and the edge of a pressure plate 5 is welded to the support members 4. A vacuum vessel A is covered by the plate 5 and surrounded by the pressure plate 5. In FIG. 1, 6 is a helium container, 7 is a thermal shield, and 8 is a supporting member such as a superconducting coil (not shown in this figure) made of a heat insulating material such as reinforced plastic.

As shown in FIG. They are fixed to the wall surface at appropriate intervals, and the end edges of the pressure plates 5 disposed on the left and right sides are welded and fixed to the surface of the inner plate 4a of the support member 4. Then, as shown in the figure, a strip plate 9 is placed along the welding line to cover the surface of the inner plate 4a constituting the support member 4 of each pressure plate 5, and one side of the strip plate 9 is attached. The edge is welded to the surface of the inner plate 4a of the support member 4, and the other edge of the strip plate 9 is welded to the inner surface of the pressure plate 5.
A ventilation passage 10a for airtightness inspection is formed between the support member 4 and the inner surface of the pressure plate 5, and any part of the strip plate 9 constituting this ventilation passage 10a is filled with helium or vacuum sealed. A small hole 11a is provided.

In the embodiment shown in FIG. 3, the end edges of the left and right pressure plates 5 are overlapped widely on the surface of the inner plate 4a of the support member 4. At the same time, the edge of the inner plate 4a is welded to the outer surface of the pressure plate 5 to form a ventilation passage 10b for airtightness inspection between the edge of the pressure plate 5 and the surface of the inner plate 4a. It was forced upon me. Furthermore, a small hole 11b filled with helium or for vacuum extraction is provided at the edge of the pressure plate 5 constituting the ventilation path 10b.

[Effects of the Invention] As described above, according to the configuration of the present invention, the following effects can be obtained.

(a) Helium gas is filled in the air passage for airtightness inspection using a small hole filled with helium or vacuum, and leak gas is detected with a helium detector along the weld line between the support member and the edge of the pressure plate. Alternatively, by connecting a vacuum device to the small vacuum outlet hole, spraying helium along the weld line between the support member and the edge of the pressure plate that make up the ventilation path, and detecting the vacuum exhaust with a helium detector. , Leakage due to poor welding can be easily discovered at the weld line between the support member and the edge of the pressure plate.

(b) Since the helium leak test is performed only from the inner surface of the vacuum container, the cross section of underground cavity excavation can be kept to the minimum necessary compared to conventional technology, making it extremely economical.

(c) Compared to the conventional leak test in which helium is filled on the outside of the vacuum container, it is economical as it does not require a large amount of helium gas.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional plan view of a part, Fig. 2 is an enlarged sectional view of the main part, Fig. 3 is an enlarged sectional view of the main part of another embodiment of the same as above, and Fig. 4 is a general superconducting power energy storage device. FIG. A...Vacuum container, 1...Bedrock, 2...Cavity, 3
... Lock bolt, 4 ... Support member, 4a ...
...Inner plate, 5...Pressure plate, 9...Strip plate,
10a... Ventilation path, 10b... Ventilation path, 11a...
...Small hole, 11b...Small hole.

Claims (1)

[Claims] 1 Support members having a frame-like structure perpendicular to the longitudinal axis of the cavity are fixed at appropriate intervals to the inner wall surface of a cavity excavated in the rock, and a vacuum pressure is applied between the surfaces of the support members. A vacuum vessel A is constructed by welding the edges of a pressure plate that resists the
In a superconducting power energy storage device in which a helium container surrounded by a thermal shield is arranged, ventilation for airtightness inspection is provided on the surface of the support member, including the weld line between the support member and the edge of the pressure plate. 1. A superconducting power energy storage device, characterized in that a passage is formed, and small holes for helium filling or vacuum suction are provided at arbitrary locations on the inner wall of the ventilation passage.