A high power ion gyro antenna

Abstract

The application discloses a high-power ion gyro antenna and relates to the technical field of ion gyro heating of fusion devices. The high-power ion gyro antenna comprises an antenna cavity part, the antenna cavity part comprises a back plate part and a side plate part, the side plate part is arranged around the outer periphery of the back plate part, the back plate part and the side plate part jointly form a containing cavity with an open side, at least one current belt is installed in the containing cavity, and each current belt comprises a connecting port part. A plurality of Faraday rods are arranged on the side plate part. Both ends of each Faraday rod are detachably connected with the side plate part, and at least one end of each Faraday rod is connected with the side plate part through an elastic sheet. The plurality of Faraday rods are arranged on the side plate part to cover the opening of the containing cavity to enclose the current belt, and at least one end of each Faraday rod is connected with the side plate part through the elastic sheet which can be elastically displaced along the length direction of the Faraday rod, so that the purpose of absorbing thermal expansion deformation of the Faraday rod and maintaining the continuity of electric contact is achieved.

Description

[0001] This invention relates to the field of ion cyclotron heating technology for fusion devices, and specifically to a high-power ion cyclotron antenna. Background Technology

[0002] Magnetic confinement fusion uses a magnetic field to confine high-temperature plasma to achieve controlled thermonuclear reactions. Among these, the deuterium-tritium reaction, due to its large reaction cross-section and relatively low ignition temperature, is currently the easiest artificial fusion reaction to achieve. During the operation of a fusion reactor, the plasma requires continuous energy replenishment through external auxiliary heating to maintain combustion. Ion cyclotron heating utilizes the resonant coupling of radio frequency electromagnetic waves with ions at the cyclotron frequency to directly transfer energy to deuterium and tritium ions, thus becoming the only existing auxiliary heating method that can directly heat deuterium and tritium ions in bulk.

[0003] The ion cyclotron heating system consists of a radio frequency (RF) source, a transmission line, and an antenna. The antenna, acting as an energy coupling terminal, is directly mounted on the vacuum chamber wall and faces the plasma. Because there is a region at the antenna front end with a plasma density lower than the cutoff density, the fast wave excited by the ion cyclotron antenna undergoes total internal reflection in this region, resulting in a high VSWR (Standing Wave Ratio) state within the transmission line and antenna. For megawatt (MW) level output power antennas, the high VSWR causes the RF energy to form a standing wave within the antenna structure, generating approximately 10... 6 The antenna operates under a strong electric field on the order of V / m. At the same time, the antenna is exposed to high-temperature plasma thermal radiation and strong electromagnetic forces for a long time, and its structural materials need to withstand large thermal and mechanical loads.

[0004] Under the aforementioned operating conditions, there is a direct correlation between the high-intensity electric field inside the antenna and structural defects. This is because the standing wave electric field strength has reached 10... 6 On the order of V / m, any burrs caused by processing errors, sharp corners resulting from structural abrupt changes, or discontinuous electrical contacts due to poor assembly within the antenna can cause localized electric field concentration. When the local electric field strength exceeds the breakdown threshold of the surrounding medium, radio frequency breakdown, i.e., arcing, will occur. Arsoning causes instantaneous impedance mismatch, reducing the power coupling efficiency to the plasma. Simultaneously, the high temperature of the arc can ablate the conductor surface and adjacent insulating materials, leading to structural damage and even functional failure. Furthermore, the antenna generates thermal stress under high temperatures and is subjected to Lorentz forces in a strong electromagnetic field. If the structural strength design is insufficient or the temperature resistance of the materials is mismatched, excessive deformation or fatigue cracks may occur.

[0005] Therefore, the risk of breakdown due to strong electric fields caused by high VSWR and the structural stress problem in high-temperature and strong electromagnetic environments together constitute the main technical obstacles to the reliable operation of megawatt-level ion cyclotron antennas. To address these issues, it is necessary to develop a high-power antenna suitable for ion cyclotron heating systems, so as to stably couple megawatt-level radio frequency power to plasma under conditions of high VSWR, high temperature, and strong electromagnetic coupling, and effectively suppress arcing and structural stress failure. Summary of the Invention

[0006] The purpose of this invention is to provide a high-power ion cyclotron antenna. By setting multiple Faraday rods at the opening of the antenna cavity to protect the current band, and connecting at least one end of each Faraday rod to a side plate through a spring that can elastically displace along its length, the technical problems of structural damage and radio frequency arcing caused by excessive thermal stress and discontinuous electrical contact due to the thermal expansion of the Faraday rod in high-temperature plasma environments are solved.

[0007] The present invention is achieved through the following technical solution: a high-power ion cyclotron antenna is provided, including an antenna cavity component, the antenna cavity component including a back plate component and a side plate component, the side plate component is disposed around the outer periphery of the back plate component, the back plate component and the side plate component together form a receiving cavity with an opening on one side, at least one current band is installed in the receiving cavity, and each current band includes a connection port component; The back panel is provided with at least one through hole, and the single through hole is used to extend the outer side of the single connection port component out of the receiving cavity and connect it to an external device. The side plate is provided with multiple Faraday rods, which cover the opening of the receiving cavity and are used to enclose the current line within the receiving cavity. Both ends of a single Faraday rod are detachably connected to the side plate, and at least one end of the single Faraday rod is connected to the side plate via a spring. The spring is configured to be able to elastically displace along the length of the Faraday rod to absorb thermal expansion deformation and maintain electrical contact continuity.

[0008] Optionally, multiple Faraday rods are arranged in parallel with gaps between them, and the spacing between two adjacent Faraday rods is equal.

[0009] Optionally, the side panel includes an upper side panel, a lower side panel, a left side panel, and a right side panel. The upper side panel is positioned above the back panel, the lower side panel is positioned below the back panel, the left side panel is positioned to the left of the back panel, and the right side panel is positioned to the right of the back panel. The upper side panel and the lower side panel are of equal length, the left side panel and the right side panel are of equal length, and the left side panel is longer than the upper side panel. The connection end of a single Faraday rod to the left or right side plate is connected to the left or right side plate via a spring clip. The connection end of a single Faraday rod to the upper or lower side plate is connected to the upper or lower side plate by a fastener.

[0010] Optionally, the Faraday rod is a hollow cylindrical structure, and both ends of the Faraday rod are provided with internal threads; One end of the spring is connected to the left or right side plate. The spring has a first connecting hole and a first screw. The first screw passes through the first connecting hole and engages with the internal thread of the Faraday rod to connect the spring to the Faraday rod.

[0011] Optionally, the fastener includes a first mounting plate, a second mounting plate, and a top plate. The first mounting plate and the second mounting plate are both connected to adjacent sides of the top plate. The first mounting plate is connected to the side of the second mounting plate. The bottom surfaces of the first mounting plate and the second mounting plate are both connected to the upper side plate or the lower side plate. The first mounting plate is provided with a second connecting hole, and a second screw is provided in the second connecting hole. The second screw is configured to pass through the second connecting hole and engage with the internal thread of the Faraday rod to connect the first mounting plate to the Faraday rod.

[0012] Optionally, a single Faraday rod is configured such that one end is connected to the left side plate and the other end is connected to the right side plate; Alternatively, a single Faraday rod may be configured such that one end is connected to the left or right side plate, and the other end is connected to the upper or lower side plate.

[0013] Optionally, a middle partition plate is provided in the cavity, the middle partition plate is connected to the side plate, and there is a gap of more than 2 cm between the middle partition plate and the back plate. The middle partition divides the housing into four small chambers, each of which is equipped with a current strip.

[0014] Optionally, the intermediate partition includes a vertical partition, a first transverse partition, and a second transverse partition, with the two ends of the vertical partition connected to the upper side plate and the lower side plate, respectively. One side of the first transverse partition is connected to the left side panel, and the other side is connected to the vertical partition through the first L-shaped plate. One side of the second transverse partition is connected to the right side panel, and the other side is connected to the vertical partition through the second L-shaped plate. The vertical partition is arranged along the center line of the receiving cavity, and the first and second transverse partitions are arranged symmetrically relative to the vertical partition.

[0015] Optionally, multiple screw holes are arranged on the outer side of the vertical partition, and anti-rotation bolts are installed in the screw holes. One side of the outer screw cap of a single anti-rotation bolt is tangent to a single Faraday rod, and the other side is tangent to the adjacent single Faraday rod.

[0016] Optionally, the current strip also includes a mounting base plate and a guide strip, one side of which is connected to the connection port fitting and the other side is connected to the mounting base plate, and the guide strip is provided with weight reduction through holes; The mounting base plate is connected to the upper or lower side plate. An oxygen-free copper pad is provided between the mounting base plate and the upper or lower side plate. The mounting base plate is connected to the oxygen-free copper pad, the upper or lower side plate by multiple fixing screws.

[0017] Compared with the prior art, the embodiments of the present invention have the following advantages and beneficial effects: 1. In this embodiment of the invention, an antenna cavity component is provided, including a back plate component and a side plate component surrounding the outer periphery of the back plate component. This allows the back plate component and the side plate component to jointly form a receiving cavity with an opening on one side, so that at least one current band can be installed in the receiving cavity. Each current band includes a connection port component, thereby providing a structural basis for the transmission and coupling of radio frequency power. At the same time, by providing at least one through hole on the back plate component, and using a single through hole to extend the outer side of a single connection port component out of the receiving cavity and connect it to an external device, an energy transmission path between the inside of the antenna and the external device is realized. Furthermore, by setting multiple Faraday rods on the side plate, these rods cover the opening of the receiving cavity and enclose the current band within the cavity, thus providing physical protection for the current band inside the cavity. On this basis, by detachably connecting both ends of each Faraday rod to the side plate, assembly and maintenance of the Faraday rod are facilitated. At least one end of each Faraday rod is connected to the side plate via a spring clip, which is designed to elastically displace along the length of the Faraday rod. When the Faraday rod undergoes thermal expansion along its length, the spring clip elastically deforms to absorb this expansion, preventing excessive thermal stress caused by the rigid constraint of the side plate. Simultaneously, the elastic contact of the spring clip maintains the continuity of electrical contact between the Faraday rod and the side plate, preventing interruption of electrical contact due to thermal expansion. Thus, while releasing thermal stress, the stability of the electrical connection is ensured, enabling the antenna to achieve continuous and reliable electrical performance while maintaining structural integrity.

[0018] 2. In this embodiment of the invention, a middle partition plate connected to the side plate is provided in the cavity, and a gap of more than 2 cm is maintained between the middle partition plate and the back plate. This avoids the formation of gaps between the middle partition plate and the back plate that are prone to electric field concentration and radio frequency breakdown due to the small gap. At the same time, the middle partition plate divides the cavity into four small chambers, and each small chamber is provided with a current band. This enables independent transmission and spatial isolation of multiple radio frequency power channels, thereby suppressing the risk of internal arcing while improving the power capacity and electromagnetic compatibility of the antenna.

[0019] 3. In this embodiment of the invention, multiple screw holes are arranged on the outer side of the vertical partition, and anti-rotation bolts are installed in the screw holes. One side of the outer screw cap of a single anti-rotation bolt is tangent to a single Faraday rod, and the other side is tangent to an adjacent single Faraday rod. Thus, the same anti-rotation bolt applies lateral constraint to two adjacent Faraday rods simultaneously, thereby preventing the Faraday rods from rotating around their own axis. This maintains the parallel arrangement accuracy and equidistant structural stability of multiple Faraday rods, ensuring that the Faraday rod array uniformly covers the opening of the cavity and maintains stable electromagnetic shielding performance.

[0020] 4. In this embodiment of the invention, the current strip includes a mounting base plate and a conductor strip, and a weight-reducing through hole is provided on the conductor strip. This reduces the overall mass of the current strip and decreases eddy current loss while meeting the requirements of radio frequency current transmission. At the same time, by setting an oxygen-free copper pad between the mounting base plate and the upper or lower side plate and fastening it with multiple fixing screws, the oxygen-free copper pad fills the contact surface to absorb the micro-displacement caused by thermal deformation. The clamping action of the multiple fixing screws ensures that a low-resistance continuous electrical contact is formed between the mounting base plate and the side plate, thereby suppressing local heating and radio frequency arcing caused by excessive resistance on the contact surface.

[0021] In general, the embodiments of the present invention provide a high-power ion cyclotron antenna, which covers the cavity opening with multiple Faraday rods on the side plate to protect the current band, and connects at least one end of a single Faraday rod to the side plate through a spring piece that can elastically displace along the length of the Faraday rod, so as to absorb the thermal expansion deformation of the Faraday rod and maintain the continuity of electrical contact. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the overall structure of the cavity end of the high-power ion cyclotron antenna provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the cavity end structure of the ion cyclotron antenna after the Faraday rod has been removed, provided in an embodiment of the present invention. Figure 3 This is a schematic diagram of the outer structure of the backplate of the high-power ion cyclotron antenna provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of a partially disassembled structure of a cyclotron antenna provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the front structure of the current band provided in an embodiment of the present invention; Figure 6 This is a schematic diagram of the back structure of the current band provided in an embodiment of the present invention; Figure 7 This is a schematic diagram of the fastener structure provided in an embodiment of the present invention; Figure 8 This is a schematic diagram of the connection structure of a Faraday rod, in which... Figure 8 'a' corresponds to the structural diagram where the left and right plates are connected at both ends respectively. Figure 8 b is a schematic diagram of the connection structure between only one end and the left or right side plate; Figure 9 A simplified planar diagram accommodating the cavity structure; Figure 10 A schematic diagram showing the setting of the screw holes for installing the anti-rotation bolts; Figure 11 This is a schematic diagram of a partial structure for the lead-out of the current-carrying connection port.

[0024] Figure reference numerals and corresponding component names: 1-Backplate, 2-Sideplate, 3-Current band, 4-Connecting port, 5-Through hole, 6-Faraday rod, 7-Spring, 8-Upper sideplate, 9-Lower sideplate, 10-Left sideplate, 11-Right sideplate, 12-Fixing component, 13-First mounting plate, 14-Second mounting plate, 15-First connecting hole, 16-Top plate, 17-Second connecting hole, 18-First screw, 19-Second screw, 20-Middle partition plate, 21-Vertical partition, 22-First transverse partition, 23-Second transverse partition, 24-First L-shaped plate, 25-Second L-shaped plate, 26-Screw hole, 27-Anti-rotation bolt, 28-Mounting base plate, 29-Guide band, 30-Oxygen-free copper pad, 31-Fixing screw, 32-Weight-reducing through hole, 33-Large port flange, 34-Waveguide flange, 35-Small flange, 36-Waveguide hole. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0027] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0028] In the description of this invention, it should be noted that the terms "first," "second," "third," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance. Example

[0029] This invention provides a high-power ion cyclotron antenna, please refer to the following reference. Figure 1 and Figure 2 As shown, the antenna includes an antenna cavity component, which is composed of a back plate component 1 and a side plate component 2 surrounding the outer periphery of the back plate component 1. The back plate component 1 and the side plate component 2 enclose a receiving cavity with an opening on one side. At least one current band 3 is installed in the receiving cavity, and each current band 3 includes a connection port component 4. At least one through hole 5 is provided on the back plate component 1. A single through hole 5 is used to extend the outer side of a single connection port component 4 out of the receiving cavity and connect it to an external device, thereby forming a radio frequency power transmission channel.

[0030] In a preferred embodiment of the present invention, the back plate 1 is not a single integral flat plate in structure, but is divided into four detachable parts (see reference). Figure 3 As shown, the various parts are connected by screws. This splicing structure allows the antenna to be used in the vacuum chamber of nuclear fusion devices with small windows, significantly improving the ease of assembly and maintenance.

[0031] Specifically, refer to Figure 2 , Figure 4 ,and Figure 9As shown, the side plate 2 includes an upper side plate 8, a lower side plate 9, a left side plate 10, and a right side plate 11. The upper side plate 8 is positioned above the back plate 1, the lower side plate 9 is positioned below the back plate 1, the left side plate 10 is positioned to the left of the back plate 1, and the right side plate 11 is positioned to the right of the back plate 1. The upper side plate 8 and the lower side plate 9 are of equal length, and the left side plate 10 and the right side plate 11 are of equal length, with the left side plate 10 being longer than the upper side plate 8. Multiple Faraday rods 6 are provided on the side plate 2. These Faraday rods 6 cover the opening of the receiving cavity and enclose the current band 3 inside the receiving cavity. The multiple Faraday rods 6 are parallel and spaced apart, with equal spacing between adjacent Faraday rods 6, thus forming a uniform electromagnetic shielding grid (see reference). Figure 1 (As shown).

[0032] In a preferred embodiment of the present invention, the Faraday rod 6 is a cylindrical hollow structure with internal threads at both ends. Multiple Faraday rods 6 are arranged in an arc shape. The curvature and bending degree of a single Faraday rod 6 are determined according to the direction of the magnetic field lines of the corresponding device. Therefore, the arc parameters of each rod are not consistent. Since the Faraday rod 6 directly faces the plasma and bears the highest heat load, its base material is preferably a molybdenum-zirconium-titanium alloy (TZM) with high electrical and thermal conductivity. To avoid the introduction of high Z impurities into the plasma by the antenna, a layer of titanium carbide (TiC) is deposited on the surface of the Faraday rod 6 by magnetron sputtering. The coating thickness is preferably 4 ± 0.5 μm. At the same time, to avoid the influence of strong magnetic fields on antenna performance, all raw materials are demagnetized so that the permeability of the raw materials is not greater than 1.02 H / m and the permeability of the finished antenna body is not greater than 1.04 H / m. In addition, it is preferable that all components are dehydrogenated after polishing to eliminate the risk of hydrogen embrittlement and ensure vacuum compatibility.

[0033] Furthermore, please refer to the following: Figure 8 and Figure 9 As shown, both ends of the single Faraday rod 6 are detachably connected to the side plate 2, and at least one end of the single Faraday rod 6 is connected to the side plate 2 through a spring piece 7. The spring piece 7 is configured to be able to undergo elastic displacement along the length direction of the Faraday rod 6 in order to absorb thermal expansion deformation and maintain electrical contact continuity.

[0034] In this embodiment of the invention, the single Faraday rod 6 can be configured such that one end is connected to the left side plate 10 and the other end is connected to the right side plate 11 (see reference). Figure 8 a), or it can be configured such that one end is connected to the left side plate 10 or the right side plate 11 and the other end is connected to the upper side plate 8 or the lower side plate 9 (see reference). Figure 8(b) This adapts to different magnetic field configurations and structural layout requirements. The connection end of a single Faraday rod 6 to the left side plate 10 or the right side plate 11 is connected to the left side plate 10 or the right side plate 11 through a spring piece 7. The connection end of a single Faraday rod 6 to the upper side plate 8 or the lower side plate 9 is connected to the upper side plate 8 or the lower side plate 9 through a fastener 12. One end of the spring piece 7 is connected to the left side plate 10 or the right side plate 11. A first connecting hole 15 is provided in the spring piece 7. A first screw 18 is provided in the first connecting hole 15. The first screw 18 passes through the first connecting hole 15 and engages with the internal thread of the Faraday rod 6, thereby fastening the spring piece 7 to the Faraday rod 6. As a preferred embodiment of the present invention, the material of the spring piece 7 is a combination of beryllium copper alloy CuBe with high thermal conductivity and high hardness and TU1 oxygen-free copper with good ductility. The fixing screw of the spring piece 7 maintains the same slope as the Faraday rod 6 to ensure sufficient force. When the Faraday rod 6 expands along its length due to plasma thermal radiation, the spring piece 7 can generate corresponding elastic sliding, thereby releasing thermal stress and avoiding the side plate 2 from forming a rigid constraint on the Faraday rod 6.

[0035] Furthermore, referring to Figure 7 As shown, the fastener 12 includes a first mounting plate 13, a second mounting plate 14, and a top plate 16. The first mounting plate 13 and the second mounting plate 14 are both connected to the adjacent sides of the top plate 16. The first mounting plate 13 is connected to the side of the second mounting plate 14. The bottom surfaces of the first mounting plate 13 and the second mounting plate 14 are both connected to the upper side plate 8 or the lower side plate 9. The first mounting plate 13 is provided with a second connecting hole 17. A second screw 19 is provided in the second connecting hole 17. The second screw 19 is configured to pass through the second connecting hole 17 and engage with the internal thread of the Faraday rod 6, thereby connecting the first mounting plate 13 to the Faraday rod 6.

[0036] In this embodiment of the invention, the first mounting plate 13, the second mounting plate 14 and the top plate 16 can be integrally set or can be detachably connected, such as by snap-fitting, welding or riveting, as long as the purpose of supporting and fixing the Faraday rod 6 can be achieved. This embodiment of the invention does not limit this.

[0037] As a preferred embodiment of the present invention, please refer to the reference. Figure 8 , Figure 10As shown, in order to prevent the Faraday rod 6 from rotating around its own axis, multiple screw holes 26 are arranged on the outer surface of the vertical partition 21. Anti-rotation bolts 27 are installed in the screw holes 26. One side of the outer screw cap of a single anti-rotation bolt 27 is tangent to a single Faraday rod 6, and the other side is tangent to an adjacent single Faraday rod 6. The orientation of each anti-rotation bolt 27 and the connecting part of the Faraday rod 6 is different according to the arc parameters of the corresponding Faraday rod 6. Through the lateral tightening action of the anti-rotation bolt 27, the same anti-rotation bolt 27 can simultaneously constrain two adjacent Faraday rods 6, thereby maintaining the stability of the arrangement angle of multiple Faraday rods 6.

[0038] Furthermore, please refer to the following: Figure 9 , Figure 2 and Figure 4 As shown, a middle partition plate 20 is provided in the cavity. The middle partition plate 20 is arc-shaped and its curvature matches the opening contour of the cavity. The middle partition plate 20 is connected to the side plate 2, and there is a gap of more than 2cm between the middle partition plate 20 and the back plate 1. This gap design can effectively prevent the formation of small gaps between the middle partition plate 20 and the back plate 1, thereby preventing radio frequency arcing caused by the gap effect in a high electric field environment.

[0039] Specifically, the intermediate partition 20 divides the accommodating cavity into four small chambers, each of which is equipped with a current band 3, thereby realizing independent transmission and spatial isolation of multiple RF power channels. The intermediate partition 20 includes a vertical partition 21, a first horizontal partition 22, and a second horizontal partition 23. The two ends of the vertical partition 21 are connected to the upper side plate 8 and the lower side plate 9, respectively. One side of the first horizontal partition 22 is connected to the left side plate 10, and its other side is connected to the vertical partition 21 through the first L-shaped plate 24. One side of the second horizontal partition 23 is connected to the right side plate 11, and its other side is connected to the vertical partition 21 through the second L-shaped plate 25.

[0040] The vertical partition 21 is arranged along the center line of the receiving cavity. The first transverse partition 22 and the second transverse partition 23 are symmetrically arranged relative to the vertical partition 21. The connection between the middle partition 20 and the side plate 2 is preferably a detachable connection. Specifically, it can be fixed by clamping with the fixing screw 31 and the oxygen-free copper pad 30. The oxygen-free copper pad 30 fills the contact surface to adapt to small deformation caused by thermal stress and ensure good electrical contact. Of course, in other embodiments of the present invention, the connection between the middle partition 20 and the side plate 2 is not limited to the above-mentioned screw clamping method. It can also be welding, riveting or snap-fitting, as long as the purpose of structural fixation and continuous electrical contact can be achieved.

[0041] Meanwhile, the number and arrangement of the fixing screws 31 are not limited in this embodiment of the invention. They can be determined according to the structural strength requirements and thermal expansion compensation. For ease of understanding, in this embodiment of the invention, the fixing screws 31 are arranged in a ring around the installation interface. Of course, in other embodiments, they can also be arranged in a straight line or in a matrix.

[0042] Furthermore, please refer to the following: Figure 4 , Figure 5 and Figure 6 As shown, the current strip 3 also includes a mounting base plate 28 and a guide strip 29. One side of the guide strip 29 is connected to the connection port 4, and the other side is connected to the mounting base plate 28. The guide strip 29 is provided with a weight reduction through hole 32. The current strip 3 has an overall arc-shaped structure to adapt to the magnetic field configuration of the plasma boundary. The guide strip 29 can be manufactured by an integrated processing method. Considering that the surface current of the current strip 3 is mainly concentrated at the edge during actual operation, a weight reduction through hole 32 is opened in the middle area of ​​the guide strip 29, so as to reduce the antenna weight and suppress eddy current loss without affecting the radio frequency current transmission.

[0043] The mounting base plate 28 is connected to the upper side plate 8 or the lower side plate 9, and an oxygen-free copper pad 30 is provided between the mounting base plate 28 and the upper side plate 8 or the lower side plate 9. The mounting base plate 28, the oxygen-free copper pad 30, the upper side plate 8 or the lower side plate 9 are connected by multiple fixing screws 31, and the multiple fixing screws 31 are arranged in a circle around the circumference of the mounting base plate 28 to increase the electrical contact area and ensure the uniformity of the connection. The oxygen-free copper pad 30 undergoes plastic deformation under the compression state to fill the micro-unevenness, thereby significantly reducing the contact resistance and adapting to the micro-displacement caused by thermal cycling.

[0044] In a preferred embodiment of the present invention, the current band 3 and the mounting base plate 28 are all made of 316L stainless steel, the port flange 33, the antenna cavity back plate and the intermediate spacer plate 20 are also made of 316L stainless steel, all screws and nuts are made of 310S stainless steel, and the vacuum seal and contact surface gasket are made of TU1 oxygen-free copper.

[0045] Specifically, please refer to the following: Figure 3 , Figure 4 and Figure 11As shown, the antenna body also includes a large port flange 33, which is a key component for connecting the antenna body to external systems. Exemplarily, the large port flange 33 is a flange plate with dimensions of 50mm × 700mm × 550mm. The large port flange 33 has four waveguide holes 36 and corresponding waveguide flanges 34 machined on it, and five small flanges 35. The small flanges 35 are used for diagnostic and antenna air supply interfaces. In this embodiment of the invention, five small flanges 35 are preferably provided. Of course, in other embodiments, four or six small flanges 35 can also be provided, as long as the interface requirements of external devices can be met. This embodiment of the invention does not impose any limitations on this.

[0046] Preferably, given the high electric field inside the antenna, all edges and corners of the components are chamfered, with a preferred chamfer size of 10mm, to prevent electric field concentration caused by small corners. All surfaces of the antenna are processed according to the cleanliness and surface roughness requirements of vacuum components. The surface roughness of the inner surface of the antenna cavity, the vacuum sealing surface, and the current band 3 is no greater than Ra 0.8, and the surface roughness of the remaining surfaces is no greater than Ra 3.2 to prevent burrs. At the same time, all screws inside the antenna cavity must not protrude from the surface and must be embedded in the mounting holes to avoid the screw heads forming electric field concentration points.

[0047] In addition, oxygen-free copper pads 30 are added to all contact surfaces of the antenna cavity and current band 3, and are tightened by as many fixing screws 31 as possible to ensure good electrical contact. Through the comprehensive combination of the above material selection, structural design and process treatment, the high-power ion cyclotron antenna of the present invention can operate stably under megawatt-level power, high VSWR and high temperature and strong electromagnetic coupling conditions, effectively reducing the probability of local breakdown and arcing, and avoiding structural damage caused by excessive thermal stress.

[0048] Finally, it should be noted that the vacuum sealing surface in this embodiment of the invention specifically refers to the sealing surface of the large port flange 33 that connects to the external vacuum system, the sealing surface of the waveguide flange 34 that connects to the external waveguide, and the sealing surface of the small flange 35 that connects to the external diagnostic or gas supply pipeline. The surface roughness of the above sealing surfaces is not greater than Ra 0.8 to ensure the reliability of the vacuum seal. Regarding the application of the oxygen-free copper pad 30, although the embodiments of the present invention focus on its placement between the current strip 3 and the side plate 2 and between the intermediate partition plate 20 and the side plate 2, it should be understood that the oxygen-free copper pad 30 is also applicable to the splicing contact surfaces between the various sections of the back plate 1, the contact surfaces between the spring sheet 7 and the left side plate 10 or the right side plate 11, the contact surfaces between the fixing member 12 and the upper side plate 8 or the lower side plate 9, the contact surfaces between the first L-shaped plate 24 and the vertical partition plate 21 and the first horizontal partition plate 22, the contact surfaces between the second L-shaped plate 25 and the vertical partition plate 21 and the second horizontal partition plate 23, and all joint surfaces that need to ensure electrical contact continuity and adapt to thermal deformation. Its thickness can be selected in the range of 0.5 mm to 3 mm according to the size of the contact surface gap, as long as it can fill the micro gap and reduce the contact resistance.

[0049] Regarding the segmented connection of the back plate component 1, although in this embodiment of the invention the back plate component 1 is divided into 4 parts and connected by screws, in other embodiments the number of segments can be adjusted to 2, 3 or more segments according to the size of the vacuum chamber window. In addition to screw connection, each segment can also be connected by pin positioning and screw fastening or snap-fit ​​connection, as long as it can facilitate disassembly and assembly through the narrow window.

[0050] The connection method between the spring piece 7 and the left side plate 10 or the right side plate 11 is not limited in this embodiment of the invention. It can be fastened with screws, welded or riveted. The application scope of the fixing screw 31 is not limited to the installation of the current strip 3 and the intermediate partition plate 20. It is also applicable to the connection between the back plate 1 sections, the connection between the port flange 33 and the side plate 2, and all occasions that require fastening and ensuring electrical contact. The number and arrangement of the fixing screw 31 can be flexibly adjusted according to the structural size and sealing requirements. The nuts matched with the fixing screw 31 are also made of 310S stainless steel.

[0051] Regarding the number of current bands 3, in this embodiment of the invention, the intermediate partition plate 20 divides the accommodating cavity into 4 small chambers and provides 4 current bands 3 accordingly. However, in other embodiments, the number of current bands 3 can be set to 1, 2 or more according to the requirements of the number of radio frequency power channels. Correspondingly, the number and layout of the partition plates of the intermediate partition plate 20 can also be adjusted. The number of Faraday rods 6 and the spacing between two adjacent Faraday rods 6 can be increased, decreased or optimized according to different plasma parameters, magnetic field configuration and electromagnetic shielding requirements.

[0052] In addition to bolt tightening, the anti-rotation bolt 27 can also be installed in other embodiments by opening a positioning groove at the end of the Faraday rod 6 and cooperating with the positioning pin on the side plate 2, as long as it can restrict the Faraday rod 6 from rotating around its own axis; the shape of the weight-reducing through hole 32 can be circular, elliptical or elongated, and its number and arrangement can be determined according to the current distribution and structural strength requirements of the conductor 29.

[0053] In addition, chamfering is not only applicable to the edges of internal components of the antenna cavity, but also to the edges of all screw holes, the inner and outer edges of the flange sealing surface, and all corners where electric field concentration may occur. The preferred chamfer size is 10mm. The requirement for screw embedding applies to all fasteners located inside the antenna cavity, including the first screw 18, the second screw 19, the anti-rotation bolt 27, and the fixing screw 31, etc., to prevent their heads from protruding from the surface and forming electric field concentration points.

[0054] Demagnetization and hydrogen removal are applicable to all metal components of the antenna, including the spring 7, the fixing part 12, the first L-shaped plate 24, the second L-shaped plate 25, etc., as long as they can reduce the magnetic permeability and eliminate hydrogen embrittlement. The size of the port flange 33 and the number of waveguide holes 36 can be adjusted according to different fusion device interface standards, and the number and purpose of the small flanges 35 can also be increased or decreased according to the actual external equipment interface requirements.

[0055] In addition, support columns can be set up. These support columns can be selectively set between the backplate 1 and the external support structure according to the overall weight of the antenna and the external support requirements. Their number, material and arrangement can be determined according to the load-bearing requirements, as long as they can provide sufficient mechanical support for the antenna.

[0056] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the invention should be included within the scope of protection of the invention. It should be noted that the structures or components illustrated in the accompanying drawings are not necessarily drawn to scale, and descriptions of well-known components, processing techniques, and processes have been omitted to avoid unnecessarily limiting the invention.

Claims

1. A high power ion gyrotron, characterized by, The antenna cavity includes a back plate (1) and a side plate (2). The side plate (2) is disposed around the outer periphery of the back plate (1). The back plate (1) and the side plate (2) together form a receiving cavity with an opening on one side. At least one current strip (3) is installed in the receiving cavity. Each current strip (3) includes a connection port (4). The back plate (1) is provided with at least one through hole (5), and the single through hole (5) is used to extend the outer side of the single connection port (4) out of the receiving cavity and connect it to an external device. The side plate (2) is provided with multiple Faraday rods (6), which cover the opening of the receiving cavity and are used to protect the current strip (3) in the receiving cavity; Both ends of the single Faraday rod (6) are detachably connected to the side plate (2), and at least one end of the single Faraday rod (6) is connected to the side plate (2) via a spring plate (7). The spring plate (7) is configured to be able to undergo elastic displacement along the length direction of the Faraday rod (6) to absorb thermal expansion deformation and maintain electrical contact continuity.

2. A high power gyrotron according to claim 1, wherein The multiple Faraday rods (6) are parallel and spaced apart, and the spacing between two adjacent Faraday rods (6) is equal.

3. A high-power ion cyclotron antenna according to claim 2, characterized in that, The side panel (2) includes an upper side panel (8), a lower side panel (9), a left side panel (10), and a right side panel (11). The upper side panel (8) is located above the back panel (1), the lower side panel (9) is located below the back panel (1), the left side panel (10) is located to the left of the back panel (1), and the right side panel (11) is located to the right of the back panel (1). The upper side plate (8) and the lower side plate (9) are of equal length, the left side plate (10) and the right side plate (11) are of equal length, and the length of the left side plate (10) is greater than the length of the upper side plate (8). The connection end of each Faraday rod (6) to the left side plate (10) or the right side plate (11) is connected to the left side plate (10) or the right side plate (11) through the spring piece (7); The connection end of each Faraday rod (6) to the upper side plate (8) or the lower side plate (9) is connected to the upper side plate (8) or the lower side plate (9) by a fastener (12).

4. A high-power ion cyclotron antenna according to claim 3, characterized in that, The Faraday rod (6) is a cylindrical hollow structure, and both ends of the Faraday rod (6) are provided with internal threads; One end of the spring piece (7) is connected to the left side plate (10) or the right side plate (11). A first connecting hole (15) is provided in the spring piece (7). A first screw (18) is provided in the connecting hole. The first screw (18) passes through the first connecting hole (15) and engages with the internal thread of the Faraday rod (6) to connect the spring piece (7) to the Faraday rod (6).

5. A high-power ion cyclotron antenna according to claim 4, characterized in that, The fastener (12) includes a first mounting plate (13), a second mounting plate (14), and a top plate (16). The first mounting plate (13) and the second mounting plate (14) are connected to the adjacent sides of the top plate (16). The first mounting plate (13) is connected to the side of the second mounting plate (14). The bottom surfaces of the first mounting plate (13) and the second mounting plate (14) are connected to the upper side plate (8) or the lower side plate (9). The first mounting plate (13) is provided with a second connecting hole (17). A second screw (19) is provided in the second connecting hole (17). The second screw (19) is configured to pass through the second connecting hole (17) and engage with the internal thread of the Faraday rod (6) to connect the first mounting plate (13) to the Faraday rod (6).

6. A high-power ion cyclotron antenna according to claim 5, characterized in that, The single Faraday rod (6) is configured such that one end is connected to the left side plate (10) and the other end is connected to the right side plate (11); Alternatively, a single Faraday rod (6) may be configured such that one end is connected to the left side plate (10) or the right side plate (11), and the other end is connected to the upper side plate (8) or the lower side plate (9).

7. A high-power ion cyclotron antenna according to claim 3, characterized in that, The cavity is provided with a middle partition plate (20), which is connected to the side plate (2), and there is a gap of more than 2 cm between the middle partition plate (20) and the back plate (1). The intermediate partition plate (20) divides the receiving cavity into four small chambers, and each of the small chambers is provided with a current strip (3).

8. A high-power ion cyclotron antenna according to claim 7, characterized in that, The intermediate partition (20) includes a vertical partition (21), a first transverse partition (22), and a second transverse partition (23). The two ends of the vertical partition (21) are connected to the upper side plate (8) and the lower side plate (9), respectively. One side of the first transverse partition (22) is connected to the left side plate (10), and the other side is connected to the vertical partition (21) through the first L-shaped plate (24). One side of the second transverse partition (23) is connected to the right side plate (11), and the other side is connected to the vertical partition (21) through the second L-shaped plate (25). The vertical partition (21) is arranged along the center line of the receiving cavity, and the first transverse partition (22) and the second transverse partition (23) are arranged symmetrically relative to the vertical partition (21).

9. A high-power ion cyclotron antenna according to claim 8, characterized in that, Multiple screw holes (26) are arranged on the outer side of the vertical partition (21). Anti-rotation bolts (27) are installed in the screw holes (26). One side of the outer screw cap of a single anti-rotation bolt (27) is tangent to a single Faraday rod (6), and the other side is tangent to an adjacent single Faraday rod (6).

10. A high-power ion cyclotron antenna according to claim 3, characterized in that, The current strip (3) also includes a mounting base plate (28) and a guide strip (29). One side of the guide strip (29) is connected to the connection port component (4), and the other side is connected to the mounting base plate (28). The guide strip (29) is provided with a weight reduction through hole (32). The mounting base plate (28) is connected to the upper side plate (8) or the lower side plate (9). An oxygen-free copper pad (30) is provided between the mounting base plate (28) and the upper side plate (8) or the lower side plate (9). The mounting base plate (28), the oxygen-free copper pad (30), the upper side plate (8) or the lower side plate (9) are connected by multiple fixing screws (31).

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