JPS6018031B2 - Helical coil for fusion devices - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a helical coil for a nuclear fusion device, and in particular to a helical coil for a nuclear fusion device. This invention relates to an improvement of a helical coil for a nuclear fusion device in which a conductor is wound in a helical shape.

A helical coil for a nuclear fusion device is used to hold the plasma housed inside the annular discharge tube, as mentioned above.
The coil conductor is wound in a helical shape around the outer periphery of the annular winding frame that covers the outside of the discharge tube. Figures 1 and 2 show a nuclear fusion diamond equipped with this helical coil. .

In the figure, reference numeral 1 denotes an annular discharge tube that houses plasma 2, and the outer periphery of the discharge tube 1 is surrounded by an annular winding frame 3 at a predetermined interval.
covered with.

A plurality of helical guides 4 are arranged on the annular winding frame 3, and an IJ helical guide groove 5 is formed in each helical guide 4.

As described above, the helical coil 6 formed by winding a plurality of coil conductors 6a in a helical shape as shown in FIG. 3 is accommodated in the helical guide groove 5. Reference numeral 7 denotes a mounting bolt for fixing the helical guide 4 to the winding frame 3, and although only a portion is shown, it is the same all around.

Further, the helical guide 4 is divided into a plurality of parts in the torus direction (arrow p direction) for easy disassembly and assembly.
Since the nuclear fusion device formed in this way has conventionally been relatively small, the coil conductor 6a can also be small, and the bending work can be done manually.

However, in recent years, there has been a desire to increase the size of nuclear fusion devices or to generate strong magnetic fields for stabilizing plasma confinement, and accordingly, the coil conductor 6a also increases in size.

It is extremely difficult to manually bend this large coil conductor 6a. That is, the coil conductor 6a is connected to the winding frame 3.
When winding the coil conductor 6a, each of the coil conductors 6a divided in the circumferential direction (direction of arrow Q in FIG. 2) of the small cross section of the crab tube 1 (cross section 0--B in FIG. 1) is individually bent by hand. However, even if the coil conductor 6a is manually bent, there is a limit to its size. According to the experience of the present inventor, the dimensions of the coil conductor 6a that can be bent by hand are as shown in FIG. The dimensions of the coil conductor 6a are 15 ribs in the middle and 53 ribs in the height, which are larger than the dimensions that can be bent by hand, and it is difficult to bend the coil conductor 6a by hand. Become something. In particular, it is well known that when the conductor dimensions are large, the section modulus increases in proportion to the height.As a result, excessive force is required to bend the coil conductor 6a, so it is necessary to manually bend the coil conductor 6a. conductor 6
It was almost impossible to bend a. For this reason, it is known that the coil conductor 6a is divided into a plurality of parts so that even if the coil conductor 6a is large, it can be easily bent by hand.

This is shown in FIG. The figure shows that the coil conductor 6a is divided into three parts in the direction of the small section of the discharge tube (arrow R direction), and each coil conductor 6a, 6a2, and 6a3 is individually bent and "wound around the winding frame 3." In this way, the dimensions of the divided coil conductors 6a, .6a2, and 6a3 are within the range that can be bent by hand as described above, so they can be easily bent by hand.However, A new problem arises due to such a configuration of the coil conductor 6a.

That is, electromagnetic force acts on the coil conductor 6a in the circumferential direction (arrow Q) and in the vertical direction (arrow R), so if the coil conductor 6a is divided, stress will occur in the coil conductor 6a due to the electromagnetic force, resulting in a strength problem. In particular, when the divided coil conductors 6a, 6a2, and 6a3 are sequentially wound around the guide groove 5 and stacked, the guide groove 5 is formed because the winding frame 3 is arranged along the discharge tube. The outer circumference side is wider than the inner circumference side.
Moreover, since the coil conductor 6a wound here has a rectangular cross section, a gap is created between the coil conductors 6a as they move outward in the vertical direction, and when electromagnetic force in the circumferential direction Q acts on this, There is an inconvenience that each coil conductor 6a, 6a2, and 6a3 may be misaligned, and if the divided parts are simply stacked, it will be difficult to withstand electromagnetic force acting in the light direction, and the strength will be reduced. This will cause problems. In this way, splitting the coil to make it easier to bend causes strength problems, and helical coils have a problem unique to helical coils in that gaps are created in the circumferential direction of the split coil conductor, which reduces the fin magnetic force. This is also a fatal drawback for helical coils that operate under

The present invention has been made in view of the above-mentioned points, and its purpose is to eliminate gaps in the circumferential direction when the coil conductor is wound, even if the coil conductor is divided into parts for easy manual work. To provide a strong helical coil for a nuclear fusion device in which split coil conductors do not shift due to electromagnetic force. In the present invention, a plurality of coil conductors each having one turn divided into a plurality of pieces are wound in a helical shape around the outer periphery of an annular winding frame that covers the outside of an annular discharge tube. When forming a helical coil, the circumferential cross-section of the discharge tube 4 of the split coil conductor is formed so that the outer conductor is larger than the inner conductor, and the split coil conductors that are adjacent to each other in the circumferential direction are The intended purpose is achieved by bringing the divided coil conductors into contact with each other and by fixing the divided coil conductors that are adjacent to each other in the vertical direction.

The present invention will be described in detail below based on embodiments shown in the drawings.

Note that the same reference numerals are used for the same parts as in the conventional one.
Embodiment of the Drawings FIG. 5 shows a state in which the hemline coil 8 of the present invention is wound on the winding frame 3 in a hemline shape, and FIG.
FIG. The helical coil 8 of the present invention also has a plurality of coil conductors 8a wound and housed in the groove 5 formed between the helical guides 4 on the winding frame 3. Small cross-section radial direction (arrow R
), and each coil conductor 8a, 8a2, and 8a3 is wound in turn and housed in the groove 6. FIG. 6 shows one turn of a coil conductor 8a consisting of divided coil conductors 8a, , 8a2, and 8a3. In the present invention, after winding each of the divided coil conductors 8a, 8a2, and 8a3, the contact portions S and S2 are fixed by brazing or the like to make them integral, and the coil conductors 8a, 8a2, and 8a3 are
The inside of the circumferential direction Q is different from each other. That is, the coil conductor 8a positioned closer to the inner circumferential side of the groove 5, the inside of the middle coil conductor 8a2 is made larger, and the middle coil conductor 8a2 is made larger.
The inside of the coil conductor 8a3, which is oriented toward the outer circumferential side, is formed to be large, so that the coil conductors 6a that are adjacent to each other in the circumferential direction are arranged in contact with each other, so that there are no gaps in all directions around the circumference. With this configuration, when winding the coil conductor 8a, since it is divided into a plurality of parts, it is easy to manually bend each of the coil conductors 8a, 8, and 8a3. Of course, after being wound, the divided coil conductors 8a, 8a2, and 8a3 are fixed to each other and are integrated, so that even if electromagnetic force acts on them and generates stress, they can sufficiently withstand it. Moreover, since the outer circumferential side of the coil conductor 8a is made larger in the circumferential direction than the inner circumferential side, and the circumferentially adjacent coil conductors 8a are in contact with each other, even if electromagnetic force acts in the circumferential direction, Even split coil conductors 8a, 8a2, 8
A3 comrades will no longer be misaligned.

In this embodiment, the divided coil conductors 8a, . 8, and 8
The inside of the circumferential direction Q of a3 becomes larger in turn as it goes in the vertical direction R, but it does not necessarily have to be this configuration, and the inside of the outer circumference of the divided coil conductor 8a is larger than the inner circumference. It is sufficient that they are formed large and in contact with each other in the central direction.

Next, the inventor's test results will be explained below.

In this test, the stress generated when electromagnetic force is applied to the coil conductor of the present invention, in which each contact portion is fixed even if the coil conductor is divided, and the conventional coil conductor, which is not fixed, was investigated. FIG. 7 shows the results. In this figure, the axis represents the electromagnetic force W applied to the coil conductor, and the vertical axis represents the stress 〇 generated in the coil conductor at that time.X represents the coil conductor of the present invention, and Y represents the conventional coil conductor. Incidentally, the coil conductor was made of steel. If the coil conductor is copper, its allowable stress (indicated by the dotted line on the horizontal axis in Figure 7) is 4k9/w, but if it is a secondary coil conductor, the electromagnetic force is 23 kg/w, which corresponds to this allowable stress value. turn into.

Therefore, if the electromagnetic force is greater than this, there is a problem in terms of strength. However, with the fixed coil conductor of the present invention, the electromagnetic force does not reach the allowable stress value even at 23k9/skin, and reaches the allowable stress value at 65k9/skin. This shows that the coil conductor of the present invention has less stress caused by electromagnetic force and has high strength. In other words, the coil conductor of the present invention can only be used with a magnetic force of up to 23k9/2, but the coil conductor of the present invention can be used up to a magnetic force of 23k9/2, so the coil conductor of the present invention has about three times the strength. It can be seen that this increases the strength and is extremely excellent. According to the helical coil for a nuclear fusion device of the present invention described above, the helical coil is arranged in a helical shape around the outer periphery of the annular winding frame that covers the outside of the annular discharge tube, and is wound one turn in the direction of the small cross section of the discharge tube. A small cross section of a discharge tube of a coil conductor divided into multiple pieces is formed in the circumferential direction so that the outer conductor is larger than the inner conductor, and the divided coil conductors adjacent to each other in the circumferential direction Since the split coil conductors are brought into contact with each other and the divided coil conductors are fixed to each other in all directions, even though the bending work of each coil conductor can be done easily by hand during winding. Because the coil conductors that are adjacent to each other in all directions around the circumference are in contact with each other, there are no gaps, and even if electromagnetic force is applied in the circumferential direction, the coil conductors will not shift. Moreover, after winding, they are fixed to each other and become a single piece. Because of this, it is possible to obtain a very strong li calcoil of this type.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a nuclear fusion device equipped with a hemi-circular coil, Fig. 2 is a cross-sectional view of the roller, Fig. 3 is a cross-sectional view of the coil conductor, and Fig. 4 is an enlarged cross-sectional view corresponding to part A in Fig. 2. 5 is an enlarged cross-sectional view of a fusion device corresponding to section A in FIG. 2, which is equipped with a helical coil for a fusion device according to the present invention, FIG. 6 is a perspective view showing a coil conductor according to the present invention, and FIG. is a characteristic diagram showing the relationship between electromagnetic force and stress in a coil conductor based on the test results of the present inventor. 1... Discharge tube, 3... Winding frame, 4... Helical guide, 5... Guide groove, 6, 8... Helical coil, 6a, 8a,... Coil conductor. Figure 4 Figure 5 Figure 6 Figure 1 Figure 2 Figure 3 Figure 7

Claims (1)

[Claims] 1. A plurality of coil conductors each having one turn divided into a plurality of pieces in the radial direction of the small cross section of the discharge tube are wound helically around the outer periphery of an annular winding frame that covers the outside of the discharge tube. In the helical coil for a nuclear fusion device, the circumferential width of the small section of the discharge tube of the divided coil conductors is formed so that the outer conductor is larger than the inner conductor, and the divided coils that are adjacent to each other in the circumferential direction are A helical coil for a nuclear fusion device, characterized in that the conductors are brought into contact with each other and the divided coil conductors adjacent to each other in the radial direction are fixed to each other.