CN111313130A - A waveguide switch for switching the transmission direction of high-power electron cyclotron waves - Google Patents

Abstract

The invention discloses a waveguide switch for switching transmission directions of high-power electronic cyclotron waves, which comprises a waveguide switch cavity, a reflector, a driving motor and first to fifth straight-through circular waveguide sections with the same size, wherein the centers of the front, rear, left, right and top five surfaces of the waveguide switch cavity are respectively provided with a circular hole with the same size, the circular holes are respectively butted with the first to fifth straight-through circular waveguide sections, the reflector is arranged in the waveguide switch cavity, the rapid switching between 4 transmission directions can be realized, and the design of the waveguide switch can meet the requirement of a large Tokamak device on rapid switching among a plurality of sets of ECRH systems. In addition, the waveguide switch is simple in structure and low in processing difficulty, the beam radius of the high-power electron cyclotron wave before and after passing through the waveguide switch is not obviously dispersed through the ellipsoidal mirror surface design of the reflecting mirror surface, and transmission is efficient and stable.

Description

A waveguide switch for switching the transmission direction of high-power electron cyclotron waves

technical field

The invention belongs to the field of microwave technology, and more particularly, relates to a waveguide switch for switching the transmission direction of high-power electron cyclotron waves.

Background technique

Electron cyclotron resonance heating (ECRH, Electron Cyclotron Resonance Heating) is a widely used plasma heating method in the current experimental research on magnetic confinement controlled thermonuclear fusion. High driving efficiency, the antenna can be far away from the plasma and so on. ECRH system is mainly composed of wave source system, transmission system, antenna system, control and protection system, etc. The power of a single system is usually between 200kW and 1MW. Common ECRH system operating frequency range is 30 ~ 200GHz. Now consider the following two situations: 1. Large tokamak devices are usually equipped with several sets of ECRH systems working at different frequency points to meet the needs of physical experiments, so they need to have the ability to switch between different ECRH systems; 2. ECRH systems The system itself should have the ability to switch high-power electron cyclotron waves to at least two different directions to meet the needs of the system's own power measurement. To this end, a waveguide switch that can switch the transmission direction of high-power electron cyclotron waves is required, and it should be able to adapt to different frequency working situations.

At present, the waveguide switch commonly used in this field usually adopts the method of laying a slide rail inside the waveguide switch cavity. A plane mirror and a straight-through waveguide section are placed on the slide rail, and the plane mirror and the straight-through waveguide section are driven by an external motor to move on the slide rail. , so that high-power electron cyclotron waves can be switched between two different transmission directions. However, it cannot meet the application requirements in the first case above, and has high requirements on the machining accuracy of the length of the slide rail. Otherwise, the resulting error will easily lead to the alignment of the plane mirror or the straight-through waveguide section and the waveguide outside the waveguide switch cavity. Problems, ranging from affecting the transmission efficiency of high-power electronic cyclotron waves, can cause ignition accidents and endanger system safety.

SUMMARY OF THE INVENTION

In view of the defects of the prior art, the purpose of the present invention is to provide a waveguide switch for switching the transmission direction of high-power electron cyclotron waves, which aims to solve the problem that the existing waveguide switch has few switchable directions among multiple sets of ECRH systems.

In order to achieve the above purpose, the present invention provides a waveguide switch for switching the transmission direction of high-power electron cyclotron waves. The frequency of the high-power electron cyclotron waves in the application of the waveguide switch is 30GHz～200GHz, and the power is 200kW～1MW, The waveguide switch includes a waveguide switch cavity, a mirror, a driving motor and first to fifth straight-through circular waveguide segments of the same size;

The center of the front, rear, left, right and top five surfaces of the waveguide switch cavity are all provided with circular holes of the same size, so as to be connected with the first to fifth through circular waveguide segments respectively; the mirror is placed in the waveguide switch cavity Internally, the drive motor is placed in the base of the reflector to control the rotation of the reflector.

Preferably, the waveguide switch cavity is a cubic cavity.

Preferably, the reflector is an ellipsoid reflector.

Preferably, the reflector can be rotated around the central axis of the fifth through-waveguide segment to 4 different positions, and in each position, the projections of the longitudinal sections of the first to fourth through-circular waveguide segments on the plane where the reflector is located are the same as The ellipsoidal profiles of the mirrors coincide exactly.

Preferably, the projection of the longitudinal section of the fifth through circular waveguide segment on the plane where the reflector is located completely coincides with the ellipsoid profile of the reflector.

Preferably, the mirror also has the function of focusing the electron cyclotron beam while changing the transmission direction of the electron cyclotron wave, so that the high-power electron cyclotron wave incident from the first to fourth through circular waveguide sections can be transmitted from the fifth through circular waveguide section. After the segment exits, its beam radius remains unchanged, and the same applies to the opposite direction.

Preferably, the reflector can be easily taken out from the bottom of the waveguide switch and replaced with ellipsoid reflection of other parameters (height of the ellipsoid, semi-minor axis of the ellipsoid, focal length of the ellipsoid mirror, semi-major axis and semi-minor axis of the ellipsoid, etc.). mirrors to accommodate high-power electron cyclotron waves of different frequencies.

Preferably, the drive motor realizes its parameter setting and rotation control through a set of motor control system.

Preferably, the first to fifth through circular waveguide segments are all standard circular waveguides.

Through the above technical solutions conceived by the present invention, compared with the prior art, the present invention installs an ellipsoidal mirror that is easily disassembled and rotated by a motor in the waveguide switch cavity, so that the switchable transmission direction of the waveguide switch is improved. There are 4 types, and they are designed to meet the needs of large tokamak devices for fast switching between multiple ECRH systems. In addition, the waveguide switch has a simple structure and low processing difficulty, thereby greatly reducing the influence of processing errors.

Description of drawings

1 is a schematic structural diagram of a waveguide switch for switching the transmission direction of a high-power electron cyclotron wave provided by an embodiment of the present invention;

2 is a side cross-sectional view of a waveguide switch provided by an embodiment of the present invention;

FIG. 3 is a schematic diagram of an internal structure of a waveguide switch provided by an embodiment of the present invention.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.

As shown in FIG. 1 , the present invention provides a waveguide switch for switching the transmission direction of high-power electron cyclotron waves. The frequency of the high-power electron cyclotron waves in the application of the waveguide switch is 30GHz～200GHz, and the power is 200kW～1MW , the waveguide switch includes a waveguide switch cavity 1, an ellipsoidal mirror 2, a drive motor 3 and first to fifth through-circular waveguide segments 4-8 of the same size; a side cross-sectional view is shown in FIG.

The waveguide switch cavity 1 is a cubic cavity, and the center of the front, rear, left, right and top five surfaces are all provided with circular holes of the same size, so as to be connected with the first to fifth through circular waveguide segments 4 to 8 respectively. The reflector 2 is placed inside the waveguide switch cavity 1, and the drive motor 3 is placed in the base of the reflector 2 to realize the rotation control of the reflector 2.

By controlling the drive motor 3 to rotate the ellipsoidal mirror clockwise/counterclockwise by 90°, 180°, and 270° respectively, it can be rotated around the central axis of the fifth through-waveguide segment to 4 different positions, each of which is a specific position. Next, the projections of the longitudinal sections of the straight-through circular waveguide sections 4 to 7 on the plane where the mirrors are located are completely coincident with the outline of the ellipsoid mirror, and the longitudinal section of the top-through circular waveguide section 8 is on the plane where the ellipsoidal mirror 2 is located. The projection on is always exactly coincident with the elliptical profile of the ellipsoidal mirror 2. Through the above operations, the high-power electron cyclotron wave can be switched in any direction from the straight-through circular waveguide section 8 to the straight-through circular waveguide sections 4-7, and the reverse direction is also applicable.

As shown in FIG. 3 , a schematic diagram of the internal structure of a waveguide switch for switching the transmission direction of high-power electron cyclotron waves. Since the size of the ellipsoid mirror 2 is designed for the transmitted high-power electron cyclotron wave of a specific frequency, its focusing effect can make the high-power electron cyclotron wave incident from the AA' plane passing through the end of the circular waveguide section 7 The beam radius will not change significantly after exiting from the BB' plane at the end of the straight circular waveguide section 8, thereby offsetting the beam radius divergence of the high-power electron cyclotron wave during the free space transmission inside the waveguide switch cavity adverse effects. The same is true for transmission in the reverse direction. Similarly, it can be seen that the transmission between the end of the straight circular waveguide section 8 and the end of any other straight circular waveguide section also has the above effect.

Those skilled in the art can easily understand that the above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention, etc., All should be included within the protection scope of the present invention.

Claims (9)

1. A waveguide switch for switching the transmission direction of high-power electron cyclotron waves, characterized in that it comprises a waveguide switch cavity (1), a mirror (2), a drive motor (3) and first to first Five straight-through circular waveguide segments (4) to (8); The centers of the front, rear, left, right and top five surfaces of the waveguide switch cavity (1) are all provided with circular holes of the same size, which are respectively connected with the first to fifth through circular waveguide segments (4) to (8). ) docking; the reflector (2) is placed inside the waveguide switch cavity (1), and the drive motor (3) is placed in the base of the reflector (2) to control the rotation of the reflector (2). 2 . The waveguide switch according to claim 1 , wherein the waveguide switch cavity ( 1 ) is a cubic cavity. 3 . 3. The waveguide switch according to claim 1, characterized in that, the reflector (2) is an ellipsoid reflector. 4 . The waveguide switch according to claim 3 , wherein the reflector ( 2 ) can be rotated to 4 different positions with the central axis of the fifth through circular waveguide segment as the rotation axis, and in each position, the first The projections of the longitudinal sections of the first to fourth through circular waveguide segments (4) to (7) on the plane where the reflector (2) is located completely coincide with the ellipsoid outline of the reflector (2). 5 . The waveguide switch according to claim 3 , wherein the projection of the longitudinal section of the fifth through circular waveguide segment ( 8 ) on the plane where the mirror ( 2 ) is located is the same as the ellipse of the mirror ( 2 ). 6 . The spherical profiles coincide exactly. 6 . The waveguide switch according to claim 3 , wherein the mirror ( 2 ) also has the function of focusing the electron cyclotron beam while changing the transmission direction of the electron cyclotron wave, which can make the electron cyclotron wave beam from the first to the fourth The beam radius of the high-power electron cyclotron waves incident on the through circular waveguide sections (4) to (7) remains unchanged after being emitted from the fifth through circular waveguide section (8), and the same applies in the opposite direction. 7 . The waveguide switch according to claim 1 , wherein the reflecting mirror ( 2 ) comprises an ellipsoidal reflecting surface, the parameters of which are determined according to the frequency of the electron cyclotron wave. 8 . 8 . The waveguide switch according to claim 1 , wherein the drive motor ( 3 ) realizes its parameter setting and rotation control through a motor control system. 9 . 9 . The waveguide switch according to claim 1 , wherein the first to fifth through circular waveguide segments ( 4 ) to ( 8 ) are all circular waveguides. 10 .

Images