JPH0126036B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention provides a nuclear fusion device in which a plurality of toroidal coils formed by winding around a donut-shaped discharge tube are arranged at approximately equal intervals in the poloidal direction of the discharge tube. Regarding.

[Prior art]

Fusion devices use magnetic fields to confine plasma inside a discharge tube. In a torus-type nuclear fusion device using a donut-shaped discharge tube, several coils called poloidal coils are arranged in the discharge tube in the case of a multipole type. This poloidal coil is arranged concentrically with the discharge tube, and when a large current flows through the coil, a concentric magnetic field is generated to compress the plasma and confine it within the discharge tube. In addition, a toroidal coil wound in a poloidal direction around the discharge tube is used to apply a magnetic field in the toroidal direction of the discharge tube to stabilize plasma confinement. Furthermore, a turbulent heating coil is provided within the discharge tube in parallel with the poloidal coil and concentrically with the discharge tube. This turbulent heating coil is designed to generate short pulses of turbulent current in the plasma by passing a short pulse of current through it, thereby heating the plasma.

FIG. 1 is an explanatory diagram showing the arrangement and connection state of a conventional toroidal coil. In FIG. 1, around the donut-shaped discharge tube 10, a plurality of solenoids 12 formed by winding the solenoids 12 constituting a toroidal coil in the poloidal direction of the discharge tube 10 extend in the toroidal direction of the discharge tube 10. They are arranged at approximately equal intervals. The plurality of solenoids 12 are connected in series in a clockwise direction, for example, by connecting wires 14, and receive current for generating a magnetic field from a power source 16. Further, a turbulent heating coil 18 is provided inside the discharge tube 10 together with a poloidal coil (not shown), and is connected to a turbulent heating coil power source 20 to heat the plasma.

In such a nuclear fusion device, the high-frequency changing magnetic field generated by the turbulent heating coil 18 generates a transmissive voltage at the connection between the solenoids forming the toroidal coil (the crossover wire 14), and There is a risk that the generated electromotive voltage will impose a large total load on the power supply 16. It also has the disadvantage of creating a large voltage difference between the toroidal coil and ground.

Therefore, as shown in FIG. 2, a loop 22 wound counterclockwise is provided to cancel the induced voltage generated in the toroidal coil. However, in a nuclear fusion device having such a structure, although there is no load on the power source 16, a large voltage difference still occurs between the ground and the folded portion 24.

[Purpose of the invention]

An object of the present invention is to provide a nuclear fusion device that can reduce the voltage difference between the toroidal coil and the ground without applying a load to the toroidal coil power supply section.

[Summary of the invention]

In the present invention, a plurality of toroidal coils provided along the toroidal direction of a donut-shaped discharge tube 10 are divided into a plurality of groups, and a power source for supplying current to these toroidal coils is provided at a position not affected by the magnetic field. Thus, the above object can be achieved.

[Embodiments of the invention]

A preferred embodiment of the nuclear fusion device according to the present invention is as follows:
A detailed explanation will be given according to the attached drawings. Note that the same reference numerals are given to the parts corresponding to the parts explained in the prior art, and the explanation thereof will be omitted.

A plurality of, for example eight, solenoids 12 arranged at approximately equal intervals in the torus direction of the discharge tube 10.
a, 12b, 12c, 12d, 12e, 12f,
12g and 12h are divided such that 12a to 12d form one set and 12e to 12h form one set. A lead wire 26 connecting the solenoid 12b and the solenoid 12c to the power source 16,
28 is pulled out, and lead wires 30 and 32 are pulled out from the solenoid 12f and the solenoid 12g, respectively, to connect to the power source 16. Furthermore, the solenoid 12a and the solenoid 12d are connected to a connecting wire 34.
The solenoid 12e and the solenoid 12h are connected by a connecting line 36.

In such an embodiment, even when a short pulse current flows through the turbulent heating coil 18, not only is there no load on the power supplies 16, 16, but
The earth tube voltage at the folded portions 38a, 38b, 40a, and 40b is reduced and dispersed to 1/4 of the turbulent heating coil voltage.

Furthermore, as shown in FIG.
8, 30, and 32 can be connected in series at a location away from the device where they are not affected by the poloidal magnetic field, and a single power source can be used. By using one power source in this way, it becomes easy to synchronize each solenoid.

FIGS. 5 and 6 show other embodiments of the nuclear fusion device according to the present invention. The embodiment shown in FIG. 5 has four solenoids 12a to 12h.
This figure shows an example in which the solenoid is divided into two groups, and the lead wire is drawn out from the middle of the solenoid forming each group (for example, the middle between the solenoid 12a and the solenoid 12b), and the connecting wires 42, 44, 46,
48 connects each set of solenoids. In this way, the number of sets of solenoids can be three or more, and the potential difference between the induced voltage generated in the solenoid and the ground can be made equal to or less than the reciprocal of each number of sets. Furthermore, it is preferable that the lead wires drawn out from each set are located at positions where the number of solenoids on the left and right sides of the lead wires in each set is the same, but the number of solenoids may be different. In this case, the voltage difference between both ends of each set and the ground is distributed to the ratio of the number of coils on the left and right sides of the lead wire.

In each of the embodiments described above, the unwinding is performed in a loop with only one turn, and the currents flowing through the solenoids 12a to 12h are all clockwise. Therefore, in a small portion, a magnetic field exists in a direction perpendicular to the drawing. Therefore, for example, as in the embodiment shown in Fig. 6, it is decided to connect the solenoids so that the current flowing through the solenoids flows alternately clockwise and counterclockwise, thereby canceling out the magnetic field in the direction perpendicular to the drawing. The plasma can be heated without being affected by the magnetic field generated in the solenoid due to the operation of the turbulent heating coil.

〔Effect of the invention〕

As explained above, according to the present invention, the toroidal coil is divided into a plurality of groups, and the power source that supplies current to these toroidal coils is provided in a position that is not affected by the magnetic field, thereby eliminating the need to impose a load on the power source. The potential difference between the toroidal coil and ground can be reduced.

[Brief explanation of drawings]

1 and 2 are diagrams showing an example of a conventional method for connecting toroidal coils in a fusion device, and FIG. 3 is an explanatory diagram of an embodiment of a method for connecting toroidal coils in a fusion device according to the present invention. Figure 4 is an explanatory diagram of an embodiment in which two groups of toroidal coils are connected in series at a position not affected by the magnetic field, and Figures 5 and 6 are illustrations of a method of connecting toroidal coils in a nuclear fusion device according to the present invention. It is a figure which shows another Example. 10...Discharge tube, 12, 12a, 12b, 12
c, 12d, 12e, 12f, 12g, 12h...
...Solenoid, 16...Power source, 18...Turbulent heating coil.

Claims (1)

[Scope of Claims] 1. A donut-shaped discharge tube that confines plasma, a poloidal coil provided within the discharge tube concentrically with the discharge tube, and a plurality of the discharge tubes provided along the toroidal direction of the discharge tube. In a nuclear fusion device having a toroidal coil wound in a surrounding poloidal direction and a turbulent heating coil provided in the discharge tube for heating the plasma, the toroidal coil is divided into a plurality of groups, and the toroidal coil is divided into a plurality of groups. A nuclear fusion device characterized by having a power source that supplies current located at a location that is not affected by magnetic fields. 2. The nuclear fusion device according to claim 1, wherein the plurality of sets of toroidal coils are connected in series in a place where they are not affected by a magnetic field.