JPH04156214A - High voltage feeder - Google Patents

Abstract

PURPOSE:To give a radiation shielding ability and high insulating property to a high voltage feeder and, at the same time, to shield radiation without making any special construction work to the perforated section of the partition of a building by forming a labyrinth structure composed of a material having a radiation shielding ability between an inner and outer tubes. CONSTITUTION:A plurality of projections 13 made of a material having a radiation shielding ability are fitted to the external surface of an inner tube 9 in the axial direction toward an outer tube and a plurality of projections 14 made of the material having the radiation shielding ability are fitted to the internal surface of an outer tube 10 in the axial direction toward the inner tube 9. The projections 13 and 14 are fitted to the inner and outer tubes 9 and 10 so that the projections 9 and 10 can form a labyrinth structure, with the projections 13 and 14 overlapping each other at some places, when the tube 9 is put in the tube 10. Therefore, no radiation leakage occurs through a high voltage feeder, because the radiation passing through the space between the inner and outer tubes 9 and 10 is scattered, absorbed, and attenuated by means of the projections 13 and 14 respectively fitted to the tubes 9 and 10.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Field of Application) The present invention relates to high voltage power supply lines, particularly those used in high radiation environments such as neutral particle injection devices for nuclear fusion devices. This invention relates to improvements in high-voltage power supply lines that supply high-voltage power to equipment that is used.

(Prior art) Generally, in a neutral particle injection device for a nuclear fusion device,
A high voltage power supply is required to obtain a high energy neutral particle beam source. Furthermore, various power supplies are required to generate ions for the ion source that serves as the neutral particle beam source. On the other hand, nuclear fusion devices generate large amounts of radiation, so
The entire device must be isolated by a radiation-resistant bulkhead;
High-voltage power supplies that require a large installation space are typically installed outside the bulkhead. Therefore, a high-voltage power supply line that penetrates the building bulkhead is used to supply power to the equipment inside the bulkhead.

Figure 7 shows a power supply system for supplying power to a fusion device using this kind of high-voltage power supply line, for example, Ito et al. Development of active particle beam device; Japan Atomic Energy Research Institute Research Report J
FIG. 2 is a block diagram conceptually representing an ion source power supply system shown in AERI-M 86-11.4 (1986). As shown in the figure, a nuclear fusion device 2, a neutral particle injection device 3, and an ion source 4 are installed inside a building partition 1. Furthermore, a high voltage power supply 5 for accelerating the neutral particle beam and an ion source power supply 6 necessary for generating ions for the ion source 4 are installed outside the building partition wall 1, and penetrate through the building partition wall 1. Electric power is supplied from these power sources by the high voltage power supply line 7 shown in FIG. The high-voltage power supply line 7 includes a tanu electric line 8 that supplies high-voltage power insulated with respect to the earth, an inner tube 9 through which this electric line 8 passes, and an inner tube 9 that is housed inside and is connected to the earth potential. an outer tube 10 fixed to;
The spacer 11 supports the inner tube 9 while insulating it from the outer tube 10.

Now, such a high voltage power supply line 7 with a structure in which no particular radiation shielding measures are taken is used to supply power to a nuclear fusion device as shown in FIG. Since the nuclear fusion device is small, the radiation dose is small, and the diameter of the high-voltage power supply line 7 is small, there was no problem in terms of radiation shielding measures.

(Issue 1i to be solved by the invention) However, in recent years, as nuclear fusion devices have become larger and more sophisticated, both the accelerating voltage and power supply capacity of neutral particle injection devices have increased, and the □ diameter of high-voltage power supply lines has increased. is getting bigger. Furthermore, as the amount of radiation generated is increasing, radiation leakage from the portions where high-voltage power supply lines penetrate building bulkheads can no longer be ignored.

As a countermeasure for this, an inner pipe 9 as shown in the longitudinal cross-sectional view of FIG.
A substance 1 having radiation shielding ability in the space between the outer tube 10 and the outer tube 10
It is conceivable to use a high voltage power supply line having a structure filled with 2. However, in addition to radiation shielding ability, this material 12 must also satisfy high insulation properties.
Poor practicality. Therefore, as shown in FIG. 10, it is conceivable to devise a structure for the penetrating portion of the building separation ill to create a labyrinth structure in which the high voltage power supply line 7 is bent multiple times.

However, in this case, there was a problem in that as the diameter of the high-voltage power supply line 7 became larger, the space for the through-hole became extremely large.

The present invention was made in order to solve these conventional problems, and it has radiation shielding ability and high insulation properties, and moreover, it can shield radiation without special construction work on the penetrating part of the building bulkhead. The purpose is to provide a high voltage power supply line that can be used.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides the above-mentioned yAli! In order to solve this problem, we developed a high-voltage supply system consisting of an inner tube through which electric wires pass to supply insulated high-voltage power to the ground, and an outer tube that supports this inner tube with an insulator and houses it inside. In electric wires, a protrusion made of a material with radiation shielding ability attached to the inner tube from the outer wall of the inner tube toward the outer tube, and a radiation shielding ability attached to the outer tube from the inner wall of the outer tube toward the inner tube. and a protrusion made of a material having.

(Function) By taking such measures, the present invention includes a protrusion made of a material having radiation shielding ability attached to the inner tube from its outer wall toward the outer tube, and a protrusion made of a material having radiation shielding ability attached to the inner tube from its inner wall toward the outer tube. A labyrinth structure is formed between the inner tube and the outer tube by the protrusion made of a material having radiation shielding ability and attached toward the tube, so that effective radiation shielding can be achieved.

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

FIG. 1 is a longitudinal sectional view showing the structure of an embodiment of the high voltage power supply line of the present invention. In this figure, the same parts as in FIG. 8 are given the same reference numerals, and detailed explanation thereof will be omitted. In this embodiment, a plurality of protrusions] 3 made of a material having radiation shielding ability are attached in the axial direction to the outer wall of the inner tube 9 toward the outer tube, and to the inner wall of the outer tube ○ in the inner tube direction. A protrusion unit 4 made of a material having radiation shielding ability toward
The structure is such that a plurality of these are attached in the axial direction. In this case, as can be seen from the cross-sectional view shown in FIG. 2, in which the high voltage power supply line in FIG. The protrusions 14 have a labyrinth structure having mutually overlapping parts when viewed from the axial direction.

Therefore, according to the configuration of the embodiment as described above, radiation passing between the inner tube 9 and the outer tube 10 is scattered by the protrusion 13 attached to the inner tube 9 and the protrusion 14 attached to the outer tube 10. , absorbed and attenuated, so there is no radiation leakage through high-voltage power lines. Furthermore, the insulation between the inner tube 9 and the outer tube 10 is the space between the protrusion 13 and the protrusion 14, between the protrusion 13 and the outer tube 10, and between the protrusion 14 and the inner tube 9. Since the projections 13 and 14 are insulated by the inert gas, there is no need to make the projections 13 and 14 of an insulating material.

In the above embodiment, a case in which one inner tube is accommodated is shown, but an embodiment in which two inner tubes 9 are accommodated is shown in the vertical cross-sectional view of FIG. 3 and B in the same figure. It is shown in FIG. 4 cut at -B. In this case as well, the effect is exactly the same as in the case where there is only one inner tube 9. Furthermore, the same effect can be obtained even if the number of inner tubes 9 is three or more. In addition,
There is no particular restriction on the order in which the protrusions 13 and 14 are arranged.

FIG. 5 and FIG. 6 are a longitudinal cross-sectional view and a cross-sectional view when the protrusion 13 and the protrusion 14 do not overlap.

If the amount of radiation generated from the fusion device is not very large, the desired purpose can be sufficiently achieved using the high voltage power supply line shown in this embodiment.

Incidentally, in an ion source of a neutral particle injection device, discharge often occurs between a high voltage section and the ground. At this time, the energy stored in the stray capacitance of the power supply and high-voltage power supply line is rapidly discharged, causing a large surge current to flow through various parts of the device, which may damage the device or cause it to malfunction.

Conventionally, as a countermeasure to this problem, a core made of magnetic material was provided in the inner tube 9 of the high voltage power supply line to suppress the surge current.
Projections 13 and 1 provided on the high voltage power supply line according to the present invention
By configuring a part of 4 using a magnetic material, it is possible to obtain a high voltage power supply line that has both radiation shielding ability and surge suppressing ability.

[Effects of the Invention] As explained above, according to the present invention, a high voltage power supply line with high radiation shielding ability can be easily realized.
It can penetrate the building bulkhead in a straight line, making a significant contribution to reducing the installation area and construction costs.

[Brief explanation of the drawing]

Figure m1/26゛Figure 2 is a vertical cross-sectional view and a cross-sectional view, respectively, of one embodiment of the high-voltage power supply line of the present invention, and Figures 3 to 6 are other embodiments of the high-voltage power supply line of the present invention. Fig. 7 is a block diagram showing the concept of supplying power to a fusion device, Fig. 8 is a longitudinal sectional view of a conventional high voltage power supply line, and Fig. 9 is a radiation FIG. 10 is a vertical cross-sectional view showing a possible structure of a high-voltage power supply line if a material with good shielding ability and insulation properties is available, and FIG. 10 is a cross-sectional view showing a labyrinth structure of a building bulkhead. 8...Electric line, 9...Inner pipe, 1o...Outer pipe, 11
...Spacer, 13...Protrusion attached to inner tube, 1
4...Protrusion attached to the outer tube. Figure 7

Claims (1)

[Claims] In a high-voltage power supply line consisting of an inner tube through which an electric line is passed for supplying high-voltage power insulated with respect to the earth, and an outer tube in which the inner tube is supported by an insulator and housed inside, the inner tube a protrusion made of a material having radiation shielding ability attached to the outer tube from the outer wall toward the outer tube; and a protrusion made of a material having radiation shielding ability attached to the outer tube from the inner wall toward the inner tube. A high voltage power supply line characterized by being equipped with.