Planar resonant cavity for planar gyrotron and method for improving output power

Abstract

The invention provides a planar resonant cavity for a planar gyrotron and a method for improving output power, and relates to the technical field of microwaves, and the planar resonant cavity comprises a resonant cavity used for increasing the energy of electromagnetic waves; wherein the energy of the electromagnetic wave is gradually increased according to the beam-wave interaction of the band-shaped electron beam and the electromagnetic wave; the electron emission surfaces are respectively arranged at the upper end and the lower end of the inner side of the cavity surface in the negative Z direction of the resonant cavity and are used for emitting strip-shaped electron beams; the electron emission surfaces at the upper end and the lower end of the inner side of the cavity surface are symmetrical based on the center YZ plane of the resonant cavity and the center XZ plane of the resonant cavity. And the baffle plates comprise a left baffle plate and a right baffle plate, and the left baffle plate and the right baffle plate have the same structure, are respectively configured in the X direction of the resonant cavity between the electron emission surface and the two ends of the resonant cavity, and are used for reflecting the electromagnetic waves so as to enhance the beam-wave interaction, increase the energy of the electromagnetic waves and increase the output power of the electromagnetic waves.

Description

Technical Field

[0001] The present disclosure relates to the field of microwave technology, and more specifically, to a planar resonant cavity for a planar gyrotron and a method for improving output power. Background Art

[0002] The planar gyrotron uses a strip electron beam and transverse electromagnetic energy extraction to replace the cylindrical structure gyrotron, which has higher output power and mode selection advantages. The double-plate resonant cavity of the planar gyrotron in the related art can obtain a low maximum output power by adjusting the structure of the output waveguide and the size of the resonant cavity itself, and the transverse output power obtained cannot be effectively improved, which is quite different from the theoretical calculation. Summary of the invention

[0003] In view of this, the present disclosure provides a planar resonant cavity for a planar gyrotron and a method for improving output power.

[0004] One aspect of the present disclosure discloses a planar resonant cavity for a planar gyrotron, comprising: a resonant cavity, for increasing the energy of an electromagnetic wave; wherein the energy of the electromagnetic wave is gradually increased according to the beam-wave interaction between a band electron beam and the electromagnetic wave; an electron emission surface, respectively disposed at the upper and lower ends of the inner side of the cavity surface in the negative Z direction of the resonant cavity, for emitting the band electron beam; wherein the electron emission surfaces located at the upper and lower ends of the inner side of the cavity surface are symmetrical based on both the YZ plane of the center of the resonant cavity and the XZ plane of the center of the resonant cavity; a baffle, comprising a left baffle and a right baffle, wherein the left baffle and the right baffle have the same structure , respectively configured in the X direction of the resonant cavity between the electron emission surface and the two ends of the resonant cavity, for reflecting the electromagnetic wave to enhance the injection-wave interaction, increase the energy of the electromagnetic wave, and increase the output power of the electromagnetic wave; wherein the distance between the left baffle and one end close to the resonant cavity is equal to the distance between the right baffle and the other end close to the resonant cavity; the left baffle includes an upper baffle and a lower baffle, and the upper baffle and the lower baffle are symmetrical based on the central XZ plane of the resonant cavity; a gap is provided between the upper baffle and the lower baffle, so that the electromagnetic wave is output from the gap.

[0005] According to an embodiment of the present disclosure, the baffle is designed with different positions and widths in the X direction, and depths of the upper baffle and the lower baffle in the Y direction, so that the electromagnetic wave can be output with maximum output power.

[0006] According to an embodiment of the present disclosure, the baffle is also suitable for generating a uniform electromagnetic field to enhance the injection-wave interaction.

[0007] According to an embodiment of the present disclosure, the interior of the planar resonant cavity is a vacuum; and the planar resonant cavity is immersed in a magnetic field.

[0008] According to an embodiment of the present disclosure, the electron emitting surface is further adapted to inject the band-shaped electron beam into the resonant cavity at a predetermined angle and a predetermined speed, so that the band-shaped electron beam transfers the energy it carries to the electromagnetic wave.

[0009] According to an embodiment of the present disclosure, the above-mentioned planar resonant cavity also includes: a mutation section, a protruding section of the cavity surface configured in the negative Z direction of the above-mentioned resonant cavity, and the height of the above-mentioned mutation section is lower than the height of the cavity surface in the negative Z direction of the above-mentioned resonant cavity; the above-mentioned electron emission surface is respectively configured at the upper and lower ends of the above-mentioned mutation section.

[0010] According to an embodiment of the present disclosure, the planar resonant cavity further includes: a gradually changing segment, and the two gradually changing segments are symmetrically arranged at two ends of the resonant cavity.

[0011] According to an embodiment of the present disclosure, the planar resonant cavity further includes: a waveguide, wherein the two waveguides are respectively connected to the two gradually varying sections, symmetrically arranged at both ends of the two gradually varying sections, and are suitable for outputting the electromagnetic waves.

[0012] According to an embodiment of the present disclosure, the cavity surface of the resonant cavity in the positive Z direction is configured as an opening; the abrupt section is configured as an opening; and both ends of the two waveguides in the X direction away from the two gradually changing sections are configured as openings.

[0013] Another aspect of the present disclosure discloses a method for increasing the output power of a planar resonant cavity of a planar gyrotron.

[0014] According to an embodiment of the present disclosure, two baffles are arranged in the lateral direction of the resonant cavity on both sides of the strip electron beam, so that the electromagnetic wave can be reflected or reflected multiple times, thereby enhancing the effect of the beam-wave interaction between the strip electron beam and the electromagnetic wave, effectively improving the lateral output power, and being closer to the theoretical predicted value. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0016] Figure 1 The schematic diagram of the structure of the planar resonant cavity in the related art is shown schematically;

[0017] Figure 2A The schematic diagram of the structure of the planar resonant cavity for a planar gyrotron according to an embodiment of the present disclosure is schematically shown;

[0018] Figure 2BA cross-sectional view in the XY direction of a planar resonant cavity for a planar gyrotron according to an embodiment of the present disclosure is schematically shown;

[0019] Figure 2C A cross-sectional view in the YZ direction of a planar resonant cavity for a planar gyrotron according to an embodiment of the present disclosure is schematically shown;

[0020] Figure 3A A schematic diagram schematically shows the electric field distribution of a planar resonant cavity without a baffle according to an embodiment of the present disclosure;

[0021] Figure 3B A schematic diagram schematically shows the electric field distribution of a planar resonant cavity for a planar gyrotron according to an embodiment of the present disclosure;

[0022] Figure 4A A schematic diagram schematically shows the amplitude of a simulated output electromagnetic wave of a planar resonant cavity without a baffle according to an embodiment of the present disclosure; and

[0023] Figure 4B The figure schematically shows the amplitude of the simulated output electromagnetic wave of the planar resonant cavity of the planar gyrotron according to the embodiment of the present disclosure. DETAILED DESCRIPTION

[0024] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0025] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0026] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0027] When using expressions such as "at least one of A, B, and C, etc.", they should generally be interpreted according to the meaning of the expression commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0028] Gyrotrons have the potential to generate megawatt-level output power. Gyrotrons are of great significance as terahertz radiation sources and are widely used in the fields of nuclear fusion plasma heating and high-power radar. Gyrotrons are devices based on electron cyclotron maser technology. Electron cyclotron maser is a mechanism that converts electron kinetic energy into electromagnetic radiation energy. Its principle is to utilize the stimulated radiation process of free electrons in a magnetic field. With the continuous increase in operating frequency, cylindrical gyrotrons are limited by their own power capacity, and the output power also shows a rapid downward trend. Planar gyrotrons have higher output power and mode selection advantages. Therefore, planar gyrotrons have great application potential.

[0029] The performance of the cylindrical gyrotron scheme can be significantly improved by using a ribbon gyrotron beam and transverse electromagnetic energy extraction. The double-planar cavity high-frequency structure of the ribbon gyrotron beam has the advantages of uniform distribution of the working mode field, relatively small ohmic loss, transverse diffraction mode selection ability, conducive to harmonic operation and convenient frequency tuning.

[0030] Figure 1 The schematic diagram of the structure of a planar resonant cavity in the related art is shown schematically.

[0031] like Figure 1 As shown in the figure, the transverse direction of the transverse electromagnetic energy extraction refers to the X direction. At a given initial velocity and incident angle, the electron beam enters the resonant cavity for beam-wave interaction, and angular clustering occurs under the relativistic effect. The transverse energy carried by the electron is transferred to the electromagnetic wave, amplifying the energy of the electromagnetic wave, and outputting a high-energy electromagnetic wave from the transverse exit of the resonant cavity.

[0032] In a simple double-plate resonant cavity, the maximum output power that can be obtained by adjusting the structure of the output waveguide and the size of the resonant cavity itself is low, and the lateral output power cannot be effectively improved, which is significantly different from the theoretical calculated value.

[0033] The embodiment of the present disclosure provides a planar resonant cavity for a planar gyrotron and a method for improving output power, comprising: a resonant cavity, for increasing the energy of an electromagnetic wave; wherein the energy of the electromagnetic wave is gradually increased according to the beam-wave interaction between a band electron beam and the electromagnetic wave; an electron emission surface, respectively arranged at the upper and lower ends of the inner side of the cavity surface in the negative Z direction of the resonant cavity, for emitting a band electron beam; wherein the electron emission surfaces located at the upper and lower ends of the inner side of the cavity surface are both symmetrical based on the YZ plane of the center of the resonant cavity and symmetrical based on the XZ plane of the center of the resonant cavity; a baffle, comprising a left baffle and a right baffle. The left baffle plate and the right baffle plate have the same structure and are respectively arranged in the X direction of the resonant cavity between the electron emission surface and the two ends of the resonant cavity, and are used to reflect the electromagnetic wave to enhance the injection-wave interaction, increase the energy of the electromagnetic wave, and increase the output power of the electromagnetic wave; wherein the distance between the left baffle plate and one end close to the resonant cavity is equal to the distance between the right baffle plate and the other end close to the resonant cavity; the left baffle plate includes an upper baffle plate and a lower baffle plate, and the upper baffle plate and the lower baffle plate are symmetrical based on the central XZ plane of the resonant cavity; there is a gap between the upper baffle plate and the lower baffle plate, so that the electromagnetic wave is output from the gap.

[0034] According to an embodiment of the present disclosure, two baffles are arranged in the lateral direction of the resonant cavity on both sides of the strip electron beam, so that the electromagnetic wave can be reflected or reflected multiple times, thereby enhancing the effect of the beam-wave interaction between the strip electron beam and the electromagnetic wave, effectively improving the lateral output power, and being closer to the theoretical predicted value.

[0035] The following will be combined Figure 2A , Figure 2B and Figure 2C , the structure of a planar resonant cavity used for a planar gyrotron is described.

[0036] Figure 2A The schematic diagram shows the structure of a planar resonant cavity for a planar gyrotron according to an embodiment of the present disclosure.

[0037] Figure 2B The cross-sectional view along the XY direction of a planar resonant cavity for a planar gyrotron according to an embodiment of the present disclosure is schematically shown.

[0038] Figure 2C A cross-sectional view in the YZ direction of a planar resonant cavity for a planar gyrotron according to an embodiment of the present disclosure is schematically shown.

[0039] like Figure 2A As shown, a planar resonant cavity 200 for a planar gyrotron includes a resonant cavity 1 , an electron emission surface 2 , a sudden change section 3 , a gradual change section 4 , a baffle 5 and a waveguide 6 .

[0040] According to an embodiment of the present disclosure, the cavity of the planar resonant cavity 200 is vacuum; the planar resonant cavity 200 is immersed in a magnetic field, for example, a magnetic field generated by a helical coil. The shell of the planar resonant cavity 200 may be an oxygen-free copper shell.

[0041] According to an embodiment of the present disclosure, the resonant cavity 1 is used to increase the energy of the electromagnetic wave. The energy of the electromagnetic wave is gradually increased according to the beam-beam interaction between the band electron beam and the electromagnetic wave. The resonant cavity 1 is a beam-beam interaction section.

[0042] According to an embodiment of the present disclosure, the electron emission surface 2 is respectively arranged at the upper and lower ends of the inner side of the cavity surface of the resonant cavity 1 in the negative Z direction, and is used to emit a band electron beam; wherein the electron emission surface 2 located at the upper and lower ends of the inner side of the cavity surface is symmetrical based on both the central YZ plane of the resonant cavity 1 and the central XZ plane of the resonant cavity 1.

[0043] According to an embodiment of the present disclosure, the electron emission surface 2 is also suitable for injecting a band electron beam into the resonant cavity 1 at a predetermined angle and a predetermined speed. The band electron beam interacts with the electromagnetic wave in the resonant cavity 1, and the band electron beam undergoes angular clustering under the relativistic effect, so that the band electron beam transfers the energy it carries to the electromagnetic wave, thereby amplifying the energy of the electromagnetic wave.

[0044] In one example, a ribbon electron beam is used to excite a target electromagnetic field and adjust the distribution and power of the electromagnetic field.

[0045] According to an embodiment of the present disclosure, the baffle 5 includes a left baffle and a right baffle, and the left baffle and the right baffle have the same structure and are respectively arranged in the X direction of the resonant cavity 1 between the electron emission surface 2 and the two ends of the resonant cavity 1, and are used to reflect electromagnetic waves to enhance the injection-wave interaction, increase the energy of the electromagnetic waves, and increase the output power of the electromagnetic waves.

[0046] According to an embodiment of the present disclosure, the distance between the left baffle and one end of the resonant cavity 1 is equal to the distance between the right baffle and the other end of the resonant cavity 1; the left baffle includes an upper baffle and a lower baffle, and the upper baffle and the lower baffle are symmetrical based on the central XZ plane of the resonant cavity 1, so as to better transmit electromagnetic waves. There is a gap between the upper baffle and the lower baffle, so that the electromagnetic waves are output from the gap.

[0047] According to the embodiment of the present disclosure, the baffle 5 is designed with different positions and widths in the X direction, and depths of the upper baffle and the lower baffle in the Y direction, so that the electromagnetic waves can be output with the maximum output power.

[0048] Figure 3A A schematic diagram schematically shows the electric field distribution of a planar resonant cavity without a baffle according to an embodiment of the present disclosure.

[0049] Figure 3BA schematic diagram schematically shows the electric field distribution of a planar resonant cavity for a planar gyrotron according to an embodiment of the present disclosure.

[0050] According to an embodiment of the present disclosure, the baffle 5 is also used to generate a uniform electromagnetic field, and the electric field distribution is as follows: Figure 3B As shown in the figure, the beam-wave interaction is enhanced. The electric field distribution of the planar resonant cavity without baffles is shown in the figure. Figure 3A The baffle 5 reflects the electromagnetic wave to a certain extent, enhancing the electric field strength in the resonant cavity 1, making the electric field in the resonant cavity 1 more evenly distributed in the X direction, thereby improving the interaction between the band electron beam and the electromagnetic wave.

[0051] According to the embodiment of the present disclosure, the mutation section 3 is configured as a protruding section of the cavity surface in the negative Z direction of the resonant cavity 1, and the height of the mutation section 3 is lower than the height of the cavity surface in the negative Z direction of the resonant cavity 1, so that the transmission of the electromagnetic wave in the negative Z direction is cut off. The electron emission surface 2 is respectively configured at the upper and lower ends of the mutation section 3.

[0052] According to the embodiment of the present disclosure, two gradually changing sections 4 are symmetrically arranged at two ends of the resonant cavity 1. The gradually changing section 4 changes the height in the Y direction so as to make the output power of the electromagnetic wave higher.

[0053] According to the embodiment of the present disclosure, two waveguides 6 are respectively connected to the two gradual change sections 4, and are symmetrically arranged at both ends of the two gradual change sections 4 for lateral output of electromagnetic waves. The thickness of the waveguide 6 in the X direction is also conducive to improving the output power of the electromagnetic waves.

[0054] According to the embodiment of the present disclosure, the cavity surface of the resonant cavity 1 in the positive Z direction is configured as an opening to transmit a band electron beam, and the planar gyrotron is connected to a collector in the positive Z direction of the resonant cavity 1 to collect the remaining electrons. The sudden change section 3 is configured as an opening to connect an electron gun. The two ends of the two waveguides 6 in the X direction away from the two gradual change sections are configured as openings to transmit electromagnetic waves.

[0055] According to an embodiment of the present disclosure, a method for increasing output power using a planar resonant cavity for a planar gyrotron is simulated using three-dimensional electromagnetic computing software.

[0056] Figure 4A The figure schematically shows the amplitude of the simulated output electromagnetic wave of the planar resonant cavity without the baffle according to the embodiment of the present disclosure.

[0057] Figure 4B The figure schematically shows the amplitude of the simulated output electromagnetic wave of the planar resonant cavity of the planar gyrotron according to the embodiment of the present disclosure.

[0058] According to the embodiment of the present disclosure, the incident voltage of the strip electron beam is set to 60 kV, the current is set to 60 A, and the inclination angle of the electron emission surface is set to 50°. The amplitude of the simulated output electromagnetic wave of the planar resonant cavity without a baffle is obtained by simulation as follows: Figure 4A As shown, the amplitude is 600, which converts to an output power of 360kW.

[0059] According to the embodiment of the present disclosure, the distance between the left baffle and the left end of the electron emission surface in the X direction is set to 1.55 mm, the depth of the upper baffle and the lower baffle of the left baffle is 1.3 mm, the width of the left baffle is 0.6 mm, the structure of the right baffle is consistent with that of the left baffle, and the distance between the right baffle and the right end of the electron emission surface in the X direction is 1.55 mm. The amplitude of the simulated output electromagnetic wave of the planar resonant cavity for the planar gyrotron obtained by simulation is as follows: Figure 4B As shown, the amplitude is 750, which is converted to an output power of 562kW. Compared with the case without a baffle, the output power increases by 56.1%.

[0060] According to the embodiments of the present disclosure, under the same resonant cavity size and the same output waveguide function, setting a suitable baffle position and depth can effectively increase the output power of the planar resonant cavity in the lateral direction.

[0061] The embodiments of the present disclosure are described above. However, these embodiments are only for illustrative purposes and are not intended to limit the scope of the present disclosure. Although the embodiments are described above, this does not mean that the measures in the various embodiments cannot be used in combination to advantage. Without departing from the scope of the present disclosure, those skilled in the art may make a variety of substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. A planar resonant cavity for a planar gyrotron, characterized in that: include: A resonant cavity, used to increase the energy of the electromagnetic wave; wherein the energy of the electromagnetic wave is gradually increased according to the beam-wave interaction between the band electron beam and the electromagnetic wave; Electron emission surfaces are respectively arranged at the upper and lower ends of the inner side of the cavity surface in the negative Z direction of the resonant cavity, and are used to emit the strip electron beam; wherein the electron emission surfaces located at the upper and lower ends of the inner side of the cavity surface are symmetrical based on both the YZ plane of the center of the resonant cavity and the XZ plane of the center of the resonant cavity; baffles, including a left baffle and a right baffle, the left baffle and the right baffle having the same structure, respectively disposed in the X direction of the resonant cavity between the electron emission surface and the two ends of the resonant cavity, and used to reflect the electromagnetic wave to enhance the injection-wave interaction, increase the energy of the electromagnetic wave, and increase the output power of the electromagnetic wave; Among them, the distance between the left baffle and one end close to the resonant cavity is equal to the distance between the right baffle and the other end close to the resonant cavity; the left baffle includes an upper baffle and a lower baffle, and the upper baffle and the lower baffle are symmetrical based on the central XZ plane of the resonant cavity; there is a gap between the upper baffle and the lower baffle so that the electromagnetic wave is output from the gap.

2. A planar resonant cavity for a planar gyrotron according to claim 1, characterized in that: The baffle is designed with different positions and widths in the X direction, and the depths of the upper baffle and the lower baffle in the Y direction, so that the electromagnetic wave can be output with the maximum output power.

3. The planar resonant cavity for a planar gyrotron according to claim 1, characterized in that: The baffle is also adapted to generate a uniform electromagnetic field to enhance the injection-wave interaction.

4. A planar resonant cavity for a planar gyrotron according to claim 1, characterized in that: The interior of the planar resonant cavity is a vacuum; the planar resonant cavity is immersed in a magnetic field.

5. The planar resonant cavity for a planar gyrotron according to claim 1, characterized in that: The electron emitting surface is also adapted to inject the strip electron beam into the resonant cavity at a predetermined angle and a predetermined speed, so that the strip electron beam transfers the energy it carries to the electromagnetic wave.

6. The planar resonant cavity for a planar gyrotron according to claim 1, characterized in that: Also includes: The mutation section is a protruding section of the cavity surface in the negative Z direction of the resonant cavity, and the height of the mutation section is lower than the height of the cavity surface in the negative Z direction of the resonant cavity; the electron emission surface is respectively configured at the upper and lower ends of the mutation section.

7. A planar resonant cavity for a planar gyrotron according to claim 6, characterized in that: Also includes: The two gradually changing sections are symmetrically arranged at two ends of the resonant cavity.

8. The planar resonant cavity for a planar gyrotron according to claim 7, characterized in that: Also includes: The two waveguides are respectively connected to the two gradually changing sections, symmetrically arranged at the two ends of the two gradually changing sections, and are suitable for outputting the electromagnetic waves.

9. A planar resonant cavity for a planar gyrotron according to claim 8, characterized in that: The cavity surface of the resonant cavity in the positive Z direction is configured as an opening; The mutation section is configured as an opening; Both ends of the two waveguides in the X direction away from the two gradually changing sections are configured as openings.

10. A method for increasing the output power of a planar resonant cavity of a planar gyrotron using any one of claims 1 to 9.

Images