JPS60195845A - Gyrotron device - Google Patents

Abstract

PURPOSE:To generate an electromagnetic wave with the large power by constituting a resonance part while using coaxial double electron beams and axially symmetrical partially transmissive mirrors. CONSTITUTION:The electromagnetic wave of an electron beam 19 is transmitted in the direction of a mirror 23 while being oscillated and amplified by a partially transmissive mirror 22. The reflection face of a mirror 23 has an oval face 40 having two focal points, namely the center 37 of the partially transmissive mirror 22 and the center 39 of the reflection face 38 of a mirror 24. Simillarly, the mirror 24 has two focal points, namely the center 41 of the mirror 23 and the center 43 of the reflection face 42 of the mirror 24, while the electromagnetic wave reflected on a refelction face 38 is reflected on the reflection face 42 while transmitting the electromagnetic wave in the direction of a mirror 25. The mirror 25 has also reflection faces 44 and 45 while being formed into an oval rotary face so as to transmit the electromagnetic wave in the Z-direction while the reflection face 45 matching its focus with that of the plasma 46. Further, an electron gun 20 is consisting of a magnetron type electron gun 47 generating a pencil-shaped electron beam 19a and a magnetron type electron gun 48 generatin an annular electron beam 19b coaxial with the electron beam 19a on its periphery.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical field to which the invention pertains] The present invention relates to a gyrotron device (= generating a magnetic beam) that heats the plasma of a nuclear fusion reactor.

[Prior art and its problems]

As shown in FIG. 1, a conventional gyrotron device includes an electron gun 1 that generates electron beams in two directions;
It mainly consists of a magnetic coil 2 that causes a cyclotron motion in the magneton beam emitted from the electron beam, and an output section 3 that resonates the electromagnetic waves obtained from this electron beam and outputs only electromagnetic waves.

The electron gun 1 includes a cathode 5 provided with an electron emission band 4, and this cathode 5.
: A first anode 6 arranged axially oppositely between the parts;
The anode 6 guides the single electron drawn out from the cathode 5 in two directions, and the second anode 7 generates a hollow electron beam 8.

In addition, the four-subject gun 1 is provided with an insulator 9 for insulating between each of the four poles 5, 6, and 7, and a power source 10, 11 for applying two voltages (between each), and a magnetic An electron gun coil 12 for shaping the child beam 8 is arranged.

The output section 3 includes a resonant section 13, an output matching section 14, a beam collector section 15, and an output waveguide #16 at the same level as the second anode 7.
In other words, the electron beam 8 led out from the electron gun 1 is connected to the magnetic coil 2 (2). The electronic vibration generated by
Make knees. Passes through the resonance part 13 and matching part 14 (
The child beam collides with the wall surface of the beam collector s15 and is converted into heat (2).The heat at this time is cooled by the wall surface of output #3 (2) and the cooling device 18 (2) through which cooling water flows. The interior of the gun 1 and the output section 3 is vacuum.

In the conventional gyrotron device, which has two configurations, because the frequency of the electronic resonance handled is high, it is not possible to increase the dimensions of the two-basic resonance part, and the excessive Joule heat generated on the resonance five wall surface (= However, it was difficult to create a high-output device.Therefore, there were drawbacks such as the necessity of arranging an extremely large number of devices in order to heat the plasma of a nuclear fusion device.

[Purpose of the invention]

This invention was made in view of the drawbacks of the conventional device described above, and provides a gyrotron device that transmits and focuses electromagnetic waves in a single direction suitable for plasma heating, and that can efficiently obtain large output. The purpose is to

[Summary of the invention]

The present invention includes an electron gun that generates a coaxial double beam, an electron beam emitted from the electron gun (a magnetic field generator that applies two magnetic fields, and a magnetic field generator that applies two magnetic fields), and a magnetic field generator that applies two magnetic fields. When passing (double electromagnetic waves, in the radial direction with respect to the traveling axis of this electron beam (- the emitted electromagnetic waves are quasi-optically reflected, resonated and amplified, and are partially transmitted through which the electromagnetic waves can be partially transmitted). It is a gyrotron device equipped with an integrated mirror and a mirror for transmitting electromagnetic waves that passes in the radial direction through the integrated partially transmitting mirror. It is a gyrotron device.

〔Effect of the invention〕

According to the present invention (2), since the resonator is constructed using a coaxial 23i electron beam and an axially symmetric partially transmitting mirror,
A mirror (=4) can reduce the applied magnetic wave intensity and reduce Joule heat, making it possible to generate high-output electromagnetic waves.Moreover, this high-output electromagnetic wave can be efficiently transmitted and focused in the target direction (2). It is possible to irradiate high-power d-magnetic waves even in specially designed areas such as plasma heating.

[Embodiments of the invention]

An embodiment of the present invention will be explained in detail below.

The gyrotron device according to the present invention (2) treats electromagnetic waves optically (2), so it is called a quasi-optical gyrotron device.
As shown in FIG.
When the electron beam 19 passes through the magnetic field, the electron beam 19
(magnetic wave quasi-optical (two-resonating and amplifying toric axially symmetric partially transmitted mirror) -2
2, a plurality of axisymmetric electromagnetic wave transmission mirror blocks 23, 24, configured to reflect the electromagnetic wave so as to change the direction in the radiation direction of the electromagnetic wave quadrupole beam 19 that has passed in the radial direction through the partially transmitting mirror 4. 25, a single beam dump base that replaces the energy of the used single beam 19 with heat (2), and a superconducting coil n that collects the dump beam 19.

The inside of this gyrotron device is evacuated through an exhaust pipe and is in a vacuum state, and an output window made of ceramics is provided so that only the output magnetic waves can be output. Incidentally, although not shown, a water cooling device is provided in a heated portion such as an electron beam dump station. Also,
The spacing between the i-lar blocks 23° and 25 is regulated by annular spacers 3t, 3z, and 33.

The electronic firearm emits an electron beam 19 by the voltage from the power supply 34.
It generates , and has a structure as described below.

The superconducting magnetic coil 21 is an electronic firearm, an axially symmetrical partially transmitting mirror 22, and an axially symmetrical mirror block 23 for transmitting electromagnetic waves.
Although it is constructed with a 5C double coil that covers the 24, it may be constructed using multiple coils, and even if it is a normal conducting coil (limited to a superconducting coil) or a permanent magnet, it can be Anything that can generate a magnetic field is fine. The annular axially symmetrical partially transmitting mirror n is made of copper, and as shown in cross section in FIG. It has a radius) and is concave around the entire circumference, reflecting electromagnetic waves emitted in the radial direction and oscillating them.

Amplify. This amplified electromagnetic wave is partially thin (
The light is transmitted through a partially transmitting mirror in which four parts (=multiple axial slots) 36 each having a concave lens cross section are formed. Axisymmetric mirror block 23 for electromagnetic wave transmission
．． 24.25 is a steel ring with a reflective surface at a predetermined angle, which transmits and focuses the 4 magnetic waves radially transmitted from the partially transmitting mirror n to the target C1. Its cross-sectional shape is similar to that of the following mirror (bifocal). It has a blue circular surface (combined cross section), and the transmission path of the electromagnetic wave is (=(
To simplify the explanation (shown in two planes), the 4&li wave of the magneton beam 19 is heated and amplified by the partially transmitting mirror t2, and transmitted in the direction of the mirror.The reflective surface of the i-ra is The focal point is a partially transmitted mirror; The cross-sectional shape of the reflecting surface is formed as a part of an elliptical shape.

Similarly, the mirror has two focal points: the center point 41 of the mirror and the center point 43 of the second reflecting surface 42 for each mirror, and the electromagnetic waves reflected by the first reflecting surface are reflected at the second reflecting surface 42. The mirror 5 also has first and second reflecting surfaces 44°45, and propagates the four magnetic waves in two directions, but especially (the first The second reflective surface 45 is formed to be an elliptical surface of rotation so as to focus the plasma 46 (21) to be heated.

As shown in FIG. 5, the Kameko firearm described above has a first magnetron type electron gun 47 that generates a pencil-shaped electron beam 19a, and a circular ring that is coaxial with the pencil-shaped m-beam 19a and on its outer periphery. It is composed of a second magnetron type sub gun 48 that generates a sub beam J9b.

The first magnetron type electron gun 47 has a first hot cathode 49
is exposed in the form of a ring and emits electrons (two pole bodies are provided, and the first Ashi gun's !41 Yoran 51 and second anode 52 are spaced apart from each other). The second magnetron type electron gun 48 consists of a second
A hot cathode 53 is arranged in a ring shape (two ring-shaped cathode bodies are provided), and a first anode 55 and a second anode 56 of a second anode gun are coaxially arranged around this cathode body 54 (two ring-shaped cathode bodies are provided). A control electrode 57 is provided between the first and second single gun (=).A control electrode 57 is provided between each of these magnetic poles from a trace source 58 so as to have a predetermined potential. Furthermore, the instantaneous insulation between the magnetic poles is provided by an insulator 59 made of ceramic to airtight the inside of the container 17.

According to the electron gun with a coaxial structure constructed in this way, the modes of electromagnetic waves that can generally oscillate can be considered to have both axially symmetrical intensity distribution and non-axially symmetrical intensity distribution. The intensity pattern of the axis of the electromagnetic wave oscillated within the symmetrical partially transmitted M-22 is expressed as e1mθ. Here, Jm, /”go, nl is the number of modes in the θ direction,
θ is a circumferential coordinate of a cylindrical coordinate system (r+θ, z) concentrated at the center of the axially symmetric partially transmitting mirror 22. The amplitude of the electromagnetic wave in the r direction for the mode l1m used here is proportional to J, 1' (Kr) near the central axis. Here J-(x)
is the Bessel function of the first kind of ma-th, Jl11'(X) = θ
, L(X)/θX. Also, -2π/λ, where λ is the wavelength of the electromagnetic wave. Since the efficiency of the gyrotron device is proportional to the square of the electromagnetic wave amplitude at the point where the electrons pass, when the radius of the annular electron beam 19b is set within an axially symmetrical mirror, Jo'(Krb) >) Jm''(Krb ) (
If m≠0), the electromagnetic wave of the mode having an axially symmetrical intensity distribution selectively oscillates (two oscillations). However, the half &rb of the annular electron beam 19b that satisfies the above formula is small, Since it is difficult to increase the output power, the magnetic gun that emits this electron beam has a coaxial structure. It amplifies the fundamental mode electromagnetic waves of M.

When the electron gun 47 injects a pencil-shaped electron beam 19a that moves in a spiral along the magnetic field near the axis of the axially symmetrical mirror n, the number that can interact with the Ia beam 19a is m=o, that is, the fundamental mode electromagnetic wave. Only. Therefore, the quasi-optical gyrotron device operates by first oscillating a fundamental mode electromagnetic wave with the pencil-shaped electron beam 19a, and then amplifying it with the annular electron beam 19b.

The gyrotron device of the present invention configured in this way is
Since the radial electromagnetic waves generated from the electron beam can be resonated and amplified over the entire circumference (two directions) and efficiently transmitted in the heating target direction (two directions), a high output device can be obtained.

[Other embodiments of the invention]

As another embodiment of the present invention, the electron gun 47 for emitting a pencil-shaped electron beam may be of any type as long as it emits quadruplets and can accelerate both the radial direction and the axial direction. In order to determine the radius of the beam 19& (2, its output ≦2, as shown in Fig. 6 (2), it is even better to use a collimator 60.

In addition, in order to convert the output electromagnetic waves into linearly polarized waves and transmit the fully formed magnetic waves to the irradiation target, for example, the center of the plasma, we installed a mirror for electromagnetic wave transmission at the final stage (a corrugate with an appropriate pattern). Alternatively, the electromagnetic waves emitted from the electromagnetic wave transmission mirror at the final stage may be reflected by a reflector plate having a large number of corrugates, and then transmitted to the plasma, which is the irradiation target.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing a conventional gyrotron device;
Figure 3 is a cross-sectional view showing a gyrotron according to an embodiment of the present invention, Figure 3 is a cross-sectional perspective view showing an axially symmetrical partially transmitting mirror, Figure 4 is an explanatory diagram showing how electromagnetic waves are transmitted, and Figure 5 is an illustration of the present invention. FIG. 6 is a sectional view showing another embodiment of the invention. 19... Bozi beam, nod... electron gun, 21...
・Magnetic coil, n...axis-symmetric i-light transmission mirror,
2.3,24゜6... Mirror block for electromagnetic wave transmission,
26...IJ child beam Danzo, ah...slot, 47...first magnetron type gun, 48.
...Second magnetron type electron gun, 60...Collimator.

Claims (8)

[Claims] (1) A magnetic field is applied to a one-son gun that generates a circular electron beam and a pencil-shaped Yako beam coaxial with this circular electron beam, and a four-son beam that is emitted by this Nemoko gun. When the applied magnetic field generator and the beam pass through the magnetic field; among the double-splitting electromagnetic waves, there is a quasi-optical (two-wave) electromagnetic wave that propagates in the radial direction of the electron beam; It is characterized by comprising an integrated partially transmitting mirror that can reflect and resonate and partially transmit electromagnetic waves, and an electromagnetic wave transmitting mirror that transmits the electromagnetic waves passed in the radial direction through the integrated partially transmitting mirror in the direction of the irradiation target. Gyrotron display. (2) A gyrotron device according to claim 1 (claim 2), characterized in that the partially transmitting mirror is an annular, axisymmetric mirror. (3) A gyrotron device according to claim 1 (2), characterized in that the partially transmitting mirror is a conductive mirror having a concave lens-shaped cross section when facing the axis (2). (4) The electromagnetic wave transmission mirror is arranged coaxially with a partially transmissive mirror, and the electromagnetic waves transmitted from the partially transmissive mirror are reflected at an angle and configured to transmit an axially symmetrical magnetic wave beam. Claim 1 (=6) A self-mounted gyrotron device. (5) The gyrotron device according to claim 1, wherein the electromagnetic wave transmission mirror has two annular reflecting surfaces formed of a single member. (6) A self-mounted gyrotron device, characterized in that the geron gun is constructed by coaxially arranging a plurality of geron guns. (7) A pencil-shaped electron beam output section (claim 'i4 characterized in that it is formed by arranging a nicolimeter)
Section 1: H-bandit's The Yairotron device. (8) Claim 1, characterized in that the pencil-shaped electron beam oscillates in a monosulfuric wave in the fundamental mode.
(Gyrotron device described in Section 2).