Resonant cavity for power input coupler exercise
By designing a resonant cavity with adjustable frequency and adjustable coupling port size, the problems of high cost and large space occupation of high-power input couplers for offline training are solved, achieving cost reduction and space saving.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- INST OF MODERN PHYSICS CHINESE ACADEMY OF SCI
- Filing Date
- 2022-12-30
- Publication Date
- 2026-06-23
AI Technical Summary
In the existing technology, offline training of high-power input couplers at each frequency requires a resonant cavity, resulting in high cost and large space occupation.
Design a resonant cavity with adjustable frequency and adjustable coupling port size. Different frequencies and coupler power output port sizes can be adjusted through a cross-shaped frequency tuning unit and a coupling port transition adapter. The inner conductor and outer conductor are connected by welding and bolts. The inner conductor and outer conductor of the resonant cavity are made of oxygen-free copper or aluminum.
It enables adjustment of different frequencies and coupler power output port sizes, reducing offline training costs and saving space.
Smart Images
Figure CN116390325B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of particle accelerators and relates to a resonant cavity for training power input couplers. Background Technology
[0002] In the field of accelerators, the main function of coaxial high-power input couplers is to provide microwave electromagnetic fields for radio frequency (RF) accelerator cavities, while simultaneously achieving impedance matching between the power source and the cavity-beam system. To verify the rationality of the coupler design and fabrication process, and to resolve issues such as surface gas degradation, microscopic burrs elimination, and reduction of surface secondary electron emission coefficients, offline high-power training is required before the high-power input coupler is installed in the RF cavity.
[0003] High-power offline training of couplers typically requires two couplers to be performed simultaneously, necessitating an intermediate transition structure to handle power transfer. For couplers using a coupling loop, the inner conductors cannot be connected; therefore, resonant cavities are used abroad for power transfer. However, their designs only allow offline training of high-power input couplers at one frequency. Accelerator applications use resonant cavities ranging from tens of MHz to thousands of MHz. Fabricating a separate resonant cavity for offline training of power input couplers at each frequency would not only increase costs but also require significant space for storage. Therefore, it is necessary to design a resonant cavity that can accommodate offline training of high-power input couplers within a specific frequency range. Summary of the Invention
[0004] To address the aforementioned problems, the purpose of this invention is to provide a resonant cavity for power input coupler training, which has advantages such as adjustable frequency and adjustable coupling port size.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] A resonant cavity for power input coupler training, comprising:
[0007] The resonant cavity includes an inner conductor and an outer conductor. The outer conductor is a shell and the inner conductor is a cylinder. The inner conductor is placed inside the space of the outer conductor. The outer conductor is provided with a vacuum extraction port and a vacuum gauge mounting port.
[0008] The coupling port is located on the outer peripheral surface of the outer conductor and is used to connect the coupler to enable power input / output resonant cavity;
[0009] The cross-shaped frequency tuning unit is placed inside the outer conductor, and the inner conductor is connected to the cross-shaped frequency tuning unit through a threaded structure.
[0010] One end of the inner conductor is connected to the outer conductor by welding.
[0011] The other end of the inner conductor is connected to the cross-shaped frequency tuning unit via a bolt structure.
[0012] The frequency of the resonant cavity is determined by the dimensions of the chamfer, radius, length, width, and height of the cross-shaped frequency tuning unit.
[0013] One end of the outer conductor is connected to the inner conductor by welding, and the other end of the outer conductor is connected to the vacuum blade flange.
[0014] A first coupling port and a second coupling port are provided on the side of the outer conductor, and the included angle between the first coupling port and the second coupling port is 180°.
[0015] A tuning port is provided on the side of the outer conductor for mounting a tuner, and the angle between the tuning port and the first coupling port is 90°.
[0016] The sealing ring material between the coupling port transition adapter and the coupler power output port is oxygen-free copper or fluororubber.
[0017] The inner conductor, outer conductor, and cross-shaped frequency tuning unit are made of oxygen-free copper or aluminum.
[0018] The resonant cavity operates at frequencies ranging from 70MHz to 350MHz.
[0019] The present invention has the following advantages due to the adoption of the above technical solutions:
[0020] By adjusting the resonant cavity frequency and the coupling port transition, couplers with different frequencies and different coupler power output port sizes can be trained offline, which not only reduces the cost of offline coupler training but also saves placement space. Attached Figure Description
[0021] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. In the drawings:
[0022] Figure 1 This is a schematic diagram of a resonant cavity structure for power input coupler training according to an embodiment of this application.
[0023] Figure 2 For the purposes of embodiments of this application, as follows Figure 1 The diagram shows a cross-sectional structure.
[0024] Figure 3 For the purposes of embodiments of this application, as follows Figure 1 The diagram shows a cross-sectional structure.
[0025] Figure 4 For the purposes of embodiments of this application, as follows Figure 3 The diagram shows a partially enlarged cross-sectional structure.
[0026] Figure 5 This is a partial enlarged view of a cross-shaped frequency tuning unit according to an embodiment of this application.
[0027] Figure 6 The curves show the power reflection coefficient and transmission coefficient of the resonant cavity at a frequency of 163.19MHz as a function of frequency.
[0028] Figure 7 The reflection coefficients (lower limit frequencies) of cross-shaped frequency tuning units with different lengths and widths at different frequency points.
[0029] Figure 8 The reflection coefficients (upper limit frequencies) of the cross-shaped frequency tuning unit at different frequency points for different lengths and widths are shown in the attached diagram. The markings in the diagram are as follows:
[0030] 1. First coupler power output port; 2. First coupling port transition adapter; 3. First coupling port; 4. First coupling ring; 5. Second coupling ring; 6. Second coupling port; 7. Second coupling port transition adapter; 8. Second coupler power output port; 9. Resonant cavity outer conductor; 10. Knife-edge flange; 11. Vacuum extraction flange; 12. Cross-shaped frequency tuning unit; 13. Resonant cavity inner conductor; 14. Tuner; 15. Tuning port; 16. High-frequency sealing groove; 17. Screw sleeve; 18. Thread. Detailed Implementation
[0031] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.
[0032] This invention provides a resonant cavity for training power input couplers, comprising a resonant cavity, a tuner, and a coupling port transition adapter. The resonant cavity allows for offline training of couplers at different frequencies by changing the cross-shaped frequency tuning unit; the coupling port size can be adjusted by changing the dimensions of the coupling port transition adapter; and frequency variations caused by machining can be compensated by changing the tuner insertion depth. One end of the resonant cavity is connected to the power output terminal of the coupler for power input, and the other end is connected to the power output terminal of another coupler for power output. This resonant cavity features adjustable frequency and adjustable coupling port size, reducing the cost of offline training of high-power couplers and saving storage space.
[0033] Taking the resonant cavity used for training a power input coupler with an operating frequency of 163.19MHz as an example, the specific structure of the resonant cavity for training a power input coupler according to the present invention will be described in detail:
[0034] The resonant cavity for offline training of a power input coupler provided by the present invention includes a resonant cavity body, a tuner 14, and a coupling port transition adapter.
[0035] like Figures 1-4 As shown, the flange of the high-power input first coupler power output port 1 with the first coupling ring 4 is connected to the flange of the first coupler port transition adapter 2. The flange of the first coupler port transition adapter 2 is connected to the flange of the first coupling port 3 of the resonant cavity, and the input power is...
[0036] Conversely, the flange of the high-power input second coupler power output port 8 with the second coupling ring 5 is connected to the flange of the second coupler port transition adapter 7, and the flange of the second coupler port transition adapter 7 is connected to the flange of the second coupling port 6 of the resonant cavity, outputting power;
[0037] The inconsistency between the dimensions of the second coupling port transition adapter and the coupler power output port 8 and the structural dimensions of the resonant cavity coupling ports 3 and 6 can be reconciled by changing the structure and size of the coupler power output ports 1 and 8.
[0038] Tuner 14 is connected to the flange of resonant cavity tuning port 15 via a flange. By changing the insertion depth of the tuning rod, the resonant cavity frequency is made to match the coupler frequency.
[0039] One end of the inner conductor 13 of the resonant cavity is connected to the outer conductor 9 of the resonant cavity by vacuum brazing or electron beam welding, and the other end of the inner conductor 13 of the resonant cavity is provided with a stainless steel threaded sleeve 17.
[0040] The thread 18 of the cross-shaped frequency tuning unit 12 is screwed into the stainless steel threaded sleeve 17, thereby connecting the conductor 13 in the resonant cavity with the cross-shaped frequency tuning unit 12. A high-frequency sealing groove 16 is provided between the stainless steel threaded sleeve 17 and the thread structure 18 of the cross-shaped frequency tuning unit 12 to place the high-frequency sealing ring.
[0041] Adjusting the chamfer radius, length, width, and height of the cross-shaped frequency tuning unit 12 can achieve changes in the frequency of the resonant cavity.
[0042] The other end of the resonant cavity outer conductor 9 is connected to the 304 stainless steel knife-edge flange 10 by vacuum brazing or electron beam welding. The knife-edge flange 10 is connected to the 304 stainless steel vacuum extraction flange 11 by bolts.
[0043] Figure 6The reflection coefficient and transmission coefficient of the resonant cavity with a center frequency of 163.19MHz are given, where the reflection coefficient is -32.3dB and the transmission coefficient is -0.195dB, which meet the design requirements.
[0044] Depend on Figure 7 It can be seen that the maximum frequency obtained by changing the length and width of the cross-shaped frequency tuning unit is less than 350MHz.
[0045] Depend on Figure 8 It can be seen that the minimum frequency obtained by changing the length and width of the cross-shaped frequency tuning unit is less than 70MHz.
[0046] According to one embodiment of this application, a resonant cavity for training a power input coupler allows power transmission across different frequency ranges to be achieved through a single cavity, such as... Figure 7-8 The diagram illustrates the frequency range and the methods for achieving frequency variations.
[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A resonant cavity for training a power input coupler, characterized in that, include: A resonant cavity, comprising an inner conductor and an outer conductor, wherein the outer conductor is a shell and the inner conductor is a column, the inner conductor being disposed within the internal space of the outer conductor, and the outer conductor being provided with a vacuum extraction port and a vacuum gauge mounting port; A coupling port, which is disposed on the outer peripheral surface of the outer conductor, is used to connect a coupler to enable power input / output to the resonant cavity; A cross-shaped frequency tuning unit is provided, wherein the cross-shaped frequency tuning unit is placed in the internal space of the outer conductor, and the inner conductor is connected to the cross-shaped frequency tuning unit through a threaded structure. The frequency of the resonant cavity is determined by the dimensions of the chamfer, radius, length, width, and height of the cross-shaped frequency tuning unit. The resonant cavity operates at a frequency of 70MHz to 350MHz. The frequency variation caused by machining is compensated by changing the insertion depth of the tuner. One end of the resonant cavity is connected to the power output terminal of the coupler to input power, and the other end is connected to the power output terminal of another coupler to output power. The maximum frequency obtained by changing the length and width of the cross-shaped frequency tuning unit is less than 350MHz, and the minimum frequency obtained by changing the length and width of the cross-shaped frequency tuning unit is less than 70MHz.
2. The resonant cavity for power input coupler training according to claim 1, characterized in that: One end of the inner conductor is connected to the outer conductor by welding.
3. The resonant cavity for power input coupler training according to claim 1, characterized in that: One end of the outer conductor is connected to the inner conductor by welding, and the other end of the outer conductor is connected to a vacuum blade flange.
4. The resonant cavity for power input coupler training according to claim 1, characterized in that: The coupling port includes a first coupling port and a second coupling port disposed on the side of the outer conductor, and the included angle between the first coupling port and the second coupling port is 180°.
5. The resonant cavity for power input coupler training according to claim 4, characterized in that: A tuning port is provided on the side of the outer conductor for mounting a tuner, and the angle between the tuning port and the first coupling port and / or the second coupling port is 90°.
6. The resonant cavity for power input coupler training according to claim 1, characterized in that: Also includes: A coupling port transition adapter is provided, which is connected to the power output port of the coupler.
7. The resonant cavity for power input coupler training according to claim 6, characterized in that: A sealing ring is provided between the coupling port transition adapter and the coupler power output port, and a sealing ring is provided between the coupling port and the coupling port transition adapter. The material of the sealing ring is oxygen-free copper or fluororubber.
8. The resonant cavity for power input coupler training according to claim 1, characterized in that: The inner conductor, the outer conductor, and the cross-shaped frequency tuning unit are made of oxygen-free copper or aluminum.