JPS5933238B2 - Poloidal coil of nuclear fusion device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a poloidal coil for a nuclear fusion device such as a plasma experimental device.

In order to generate plasma for nuclear fusion, there are devices that can contain plasma using a strong magnetic field.

If this magnetic field has a "slop" that is generally referred to as an error magnetic field, it traps plasma and has an adverse effect on plasma control.Therefore, it is necessary to make the error magnetic field as small as possible.
A poloidal coil structure conventionally used in nuclear fusion devices, plasma experiment equipment, etc. is constructed by layering a plurality of coil conductors 2 insulated by an insulating material 1, as shown in Fig. 1, for example. There is a layered coil 3, but after the coil conductor is wound once as shown in Fig. 2,
A portion passing over to the next layer, that is, a crossing portion 4 is necessary, and the above-mentioned error magnetic field is generated from this crossing portion 4.

In addition, the input line 5 and output line 6 connected to each end of the coil serve as feeder lines and cause an error magnetic field. Third
Figure 4 and Figure 4 are other examples of conventionally used coil structures, which are composed of four coil conductors, but in this case as well, a transition section 4 is required as in the layered coil conductor. , this is the cause of the error magnetic field. Furthermore, the input line 5 and the output line 6 are power supply lines, and the greater the distance between them, the larger the error magnetic field becomes. As shown in Figure 5,
If the input end 7 and output end 8 of the coil conductor are butted together as a single winding, there will be no crossover part, and the error magnetic field will be reduced by that amount, but the input wire 4 and output wire that make up the feeder line will be removed. The distance between the conductor centers of No. 5 is not less than the thickness of the conductor, and this distance between the conductor centers is the cause of the generation of an error magnetic field. Coaxial cables are generally used as power feed lines that do not generate external magnetic fields, but they are difficult to adapt to power feed lines that carry large currents. Furthermore, the structure for reducing the error magnetic field in the portion transitioning from the coil to the feeder line becomes considerably complex. Therefore, it is an object of this invention to provide a poloidal coil for a nuclear fusion device having a structure with a small error magnetic field.The details of this invention will be described below with reference to FIGS. 6 and 7 showing one embodiment. explain.

In Figure 6, the coil conductor 10 with one turn is connected to the input end 11.
It starts from , goes around once, and ends at the output end 12 .

A feed line section 13 is provided between the input end 11 and the output end 12. The feed line section 13 consists of three plate-shaped conductors located in parallel, namely, an input line 14 extending from the input end 11 substantially perpendicularly to the axis of the coil conductor, and an input line 14 extending from the output end 12 to the axis of the coil conductor. It is composed of two output lines 15} and L6 that extend substantially perpendicularly and spaced apart from each other.

Input line 14 is sandwiched between output lines 15 and 16, and their conductor centers coincide with each other. A sufficient distance is maintained between the output line 15 and the output line 16 to accommodate the input line 14. The input line and the output line are arranged in parallel with each other with an electrical insulating material (not shown) interposed therebetween to form a power supply line section 13 shown in FIG. What should be noted here is the direction of the current flowing through the feed line section 13, and the direction of the current flowing through the output line 1.
Currents in the same direction flow through input lines 5 and 16, and currents in the opposite direction flow through input line 14. In the coil structure configured in this manner, the output wires 15 and 16 are arranged on both sides of the input wire 14, and the current flowing through the output wires 15 and 16 and the current flowing through the input wire 14 are in opposite directions. Therefore, the feeder line has a configuration similar to that of a coaxial cable, and the generation of error magnetic fields is extremely small. In addition, in the conventional structure as shown in FIG. 5, the gap between the feeder lines could not be reduced due to the thickness of the coil conductor, whereas in the coil structure according to the present invention, the gap between the feeder lines can be reduced to almost zero. , the cause of the error magnetic field can be eliminated. As is clear from the above explanation, according to the present invention, it is possible to reduce the error magnetic field generated from the feeder line without creating a crossover structure. When applied to a nuclear fusion device, it is possible to obtain a poloidal coil for a nuclear fusion device that can have extremely good performance.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing a conventional layered coil, Fig. 2 is a cross-sectional view showing a transition section of a conventional layered coil, and Fig. 3 is an explanation showing a transfer section of a conventional coil composed of four conductors. 4 is a sectional view of the coil at the portion shown in FIG. 3, FIG. 5 is a perspective view showing the feed line portion of a conventional coil consisting of one turn, and FIG. 6 is an embodiment of the present invention. FIG. 7 is an exploded view of the feeder line shown in FIG. 6. FIG. 10... Coil conductor, 11... Input end, 12... Output end, 13... Feed line section, 14... Input line , 15, 16... Output line.

Claims (1)

[Scope of Claims] 1. A nuclear fusion device comprising a coil conductor having an input end and an output end, and a feed line portion having an input line connected to the input end and an output line connected to the output end. In the poloidal coil, an input end and an output end of the coil conductor are arranged facing each other on a coaxial line, and one of the input line and the output line is connected from the input end or the output end to the axis line. a plurality of plate-shaped conductors extending substantially perpendicularly and parallel to each other, the other of the input line and the output line extending substantially perpendicularly to the axis from the input end or the output end; A poloidal coil for a nuclear fusion device, characterized in that it is a plate-shaped conductor that is inserted between the plate-shaped conductors and forms a feed line portion having a width substantially equal to the width of the coil conductor. 2. The plurality of plate-shaped conductors are two conductors spaced apart from each other, and the other of the input line and the output line is a single conductor inserted between the two conductors. A poloidal coil for a nuclear fusion device according to claim 1. 3. A poloidal coil for a nuclear fusion device according to claim 1 or 2, wherein the coil conductor has a single-turn coil structure.