Built-in permanent magnet generating device

Abstract

The invention discloses a built-in permanent magnet generating device which is built in a relativistic magnetron and comprises internal magnetic steel which comprises a first permanent magnet ring, a second permanent magnet ring and a plurality of fan-shaped permanent magnet blocks, the magnetizing directions of the first permanent magnet ring and the second permanent magnet ring are in radial orientation, and the magnetizing directions of the fan-shaped permanent magnet blocks are in radial orientation. The fan-shaped permanent magnet block is embedded in an anode blade of the relativistic magnetron; and the peripheral yoke is arranged between the internal magnetic steel and the outer wall of the relativistic magnetron. According to the relativistic magnetron, the usage amount of the magnetic steel is reduced, meanwhile, the peripheral leakage flux of the magnetic circuit system can be reduced, the utilization rate of magnetic lines is improved, miniaturization and light weight of the relativistic magnetron can be achieved, the overall energy consumption is reduced, and the multi-platform application requirement is met.

Description

Technical Field

[0001] The present application belongs to the field of microwave and electromagnetic field technology, and in particular, relates to a built-in permanent magnet generating device. Background Art

[0002] Relativistic magnetron is a relatively mature and widely reported high-power microwave source. It has the advantages of simple structure, relatively low processing cost, strong adaptability to voltage waveform, long service life, easy oscillation, and high output power. At the same time, relativistic magnetron has the potential for miniaturization and is very competitive on mobile platforms, so it has attracted the attention of various research institutions and universities. Relativistic magnetron requires an external magnetic field to work. The common magnetic field is realized by solenoid magnetic field. When the microwave source is working, it needs to provide not only high-voltage pulse drive power but also power required for coil magnetic field work. The huge power supply system greatly increases the volume and weight of the entire system, and consumes a lot of energy, reducing the overall energy efficiency of the high-power microwave source. In order to reduce the coil magnetic field cooling device and improve the efficiency, the magnetic field coil power supply is usually pulsed. Therefore, in order to synchronize the voltage and magnetic field when the microwave source is working, a synchronous controller is required. In addition, when the pulse is repeated, the electromagnetic system also needs cooling and protection devices, which greatly limits the miniaturization, engineering and practicality of the relativistic magnetron, and greatly limits its application range.

[0003] Compared with electromagnetic systems, permanent magnet systems have the advantages of small size, light weight, no extra energy consumption and the ability to provide a stable magnetic field. Therefore, the development of permanent magnet generation technology is one of the important means to realize the practical application of high-power microwave sources. Most of the existing permanent magnet generation devices are located outside the relativistic magnetron, or most of the magnets are located outside the relativistic magnetron. In order to meet the magnetic field strength requirements in the working area, a large amount of permanent magnets are required, which will limit the miniaturization of the equipment. Summary of the invention

[0004] The purpose of this application is to overcome the defects of the prior art and provide a built-in permanent magnet generating device, which is embedded in the outer cylinder of a relativistic magnetron and overlaps with the internal structure of the anode blade of the relativistic magnetron. It has the characteristics of less leakage flux, high magnetic field intensity and compact structure.

[0005] The purpose of this application is achieved through the following technical solutions:

[0006] A built-in permanent magnet generating device, the device is built inside a relativistic magnetron, the device comprises:

[0007] Internal magnetic steel, the internal magnetic steel comprising a first permanent magnetic ring and a second permanent magnetic ring with radial orientation in the magnetization direction, and a plurality of sector-shaped permanent magnetic blocks with radial orientation in the magnetization direction, the sector-shaped permanent magnetic blocks being embedded inside the anode blade of the relativistic magnetron;

[0008] The peripheral yoke is arranged between the internal magnetic steel and the outer wall of the relativistic magnetron.

[0009] Furthermore, the first permanent magnet ring and the second permanent magnet ring are respectively located at two ends of the anode of the relativistic magnetron and have opposite magnetization directions.

[0010] Furthermore, half of the sector-shaped permanent magnet block is close to the first permanent magnet ring and has the same magnetization direction as the first permanent magnet ring, and the other half of the sector-shaped permanent magnet block is close to the second permanent magnet ring and has the same magnetization direction as the second permanent magnet ring.

[0011] Furthermore, the inner radius of the first permanent magnet ring and the second permanent magnet ring are the same and are less than or equal to the inner radius of the anode of the relativistic magnetron, the inner radius of the fan-shaped permanent magnet block is smaller than the inner radius of the anode blade of the relativistic magnetron, and the opening angle of the fan-shaped permanent magnet block is smaller than the opening angle of the anode blade of the relativistic magnetron.

[0012] Furthermore, the inner radius of the outer yoke is the same as the outer radius of the first permanent magnet ring and the second permanent magnet ring, and the outer radius is smaller than the outer wall of the outer tube of the relativistic magnetron.

[0013] Furthermore, the internal magnetic steel is made of samarium cobalt permanent magnets and processed into tile-shaped magnets.

[0014] Furthermore, the first permanent magnet ring, the second permanent magnet ring and the sector-shaped permanent magnet are formed by magnetizing and bonding the tile-shaped magnets.

[0015] Furthermore, the first permanent magnet ring, the second permanent magnet ring and the sector-shaped permanent magnet are bonded and fixed to the outer yoke by insulating glue.

[0016] The beneficial effects of this application are:

[0017] (1) The built-in permanent magnet generating device for the relativistic magnetron designed in the present application is embedded in the relativistic magnetron, making full use of the structural characteristics of the anode of the relativistic magnetron and the space at both ends of the anode, replacing the internal structure of the anode blade of the relativistic magnetron with a fan-shaped magnetic steel, without increasing the lateral size of the system, effectively reducing the overall volume and weight of the permanent magnet relativistic magnetron, reducing the demand for magnetic steel, improving the lightweight and miniaturization level of the system, and having the characteristics of a long and stable uniform magnetic field in the working area.

[0018] (2) The outer yoke iron outside the magnetic steel of the present application can form a pole shoe, so that the external magnetic lines of force are guided through the pole shoe, effectively reducing the external stray magnetic field; the introduction of the internal fan-shaped magnetic steel improves the uniformity of the axial magnetic field in the working area. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the structure of a built-in permanent magnet relativistic magnetron according to an embodiment of the present application;

[0020] Figure 2 It is a schematic longitudinal section of a built-in permanent magnet generating device according to an embodiment of the present application;

[0021] Figure 3 is a schematic cross-sectional view of a built-in permanent magnet generating device according to an embodiment of the present application;

[0022] Figure 4 Schematic diagram of the magnetization direction of the axially oriented permanent magnetic ring in the circular direction of the built-in permanent magnetic generating device of the embodiment of the present application;

[0023] Figure 5 Schematic diagram of the magnetization direction of the axially oriented sector-shaped magnetic steel in the circular direction of the built-in permanent magnet generating device of the embodiment of the present application;

[0024] Figure 6 The magnetic field distribution at the central axis of the built-in permanent magnet generating device in the embodiment of the present application;

[0025] Figure 7 This is the radial magnetic field distribution at the center of the built-in permanent magnet generating device in the embodiment of the present application.

[0026] 1-relativistic magnetron outer cylinder, 2-permanent magnetic ring, 3-sector magnet, 4-outer yoke, 5-anode blade, 6-emitting cathode, 7-interaction zone. DETAILED DESCRIPTION

[0027] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0028] Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of this application.

[0029] The existing permanent magnet system has the disadvantage of magnetic leakage and requires a large number of permanent magnets, which makes it impossible to achieve miniaturization of the equipment.

[0030] In order to solve the above technical problems, the following embodiments of a built-in permanent magnet generating device of the present application are proposed.

[0031] This embodiment proposes a solution of embedding a built-in permanent magnet generating device inside a relativistic magnetron. Figure 1-Figure 3 ,like Figure 1 FIG. 1 is a schematic diagram of the structure of a built-in permanent magnet relativistic magnetron according to an embodiment of the present application. Figure 2 FIG. 1 is a schematic longitudinal section of a built-in permanent magnet generating device according to an embodiment of the present application. Figure 3 Shown is a schematic cross-sectional view of a built-in permanent magnet generating device according to an embodiment of the present application.

[0032] The internal permanent magnet generating device proposed in this embodiment is embedded in the outer tube 1 of the relativistic magnetron, and the device is composed of internal magnetic steel and peripheral yoke 4. The internal magnetic steel includes a permanent magnetic ring 2 and a sector-shaped magnetic steel 3.

[0033] In this embodiment, there are two permanent magnetic rings 2, which are respectively arranged at the two ends of the anode of the relativistic magnetron.

[0034] In this embodiment, the magnetic steel is made of high temperature resistant samarium cobalt permanent magnets and processed into tile-shaped magnets. The remanence of the permanent magnets is Br = 1.1 T. After magnetization, some tile-shaped permanent magnets are bonded into axial permanent magnet rings 2. Figure 4 ,like Figure 4 The figure shows a schematic diagram of the magnetization direction of the permanent magnet ring axially oriented in the circular direction of the built-in permanent magnet generating device of the embodiment of the present application, wherein the magnetization direction of one permanent magnet ring 2 axially oriented in the circular direction is outer S pole and inner N pole, and the magnetization direction of the other permanent magnet ring 2 axially oriented in the circular direction is outer N pole and inner S pole. The magnetization direction of the permanent magnet ring 2 is radial orientation. The inner diameter of the two permanent magnet rings 2 axially oriented in the circular direction is Rin=38mm, the outer diameter is Rout=87mm, and the thickness is h1=45mm.

[0035] As an implementation mode, in this embodiment, the permanent magnet ring 2 may be adjacent to the two ends of the anode, or may be at a certain distance from the two ends of the anode.

[0036] After magnetization, some tile-shaped permanent magnets are bonded to form fan-shaped permanent magnets 3. The size of each fan-shaped permanent magnet 3 is equal. The number of fan-shaped permanent magnets 3 is twice the number of anode blades 5 of the relativistic magnetron. In this embodiment, the number of anode blades 5 is 6, so 6 fan-shaped permanent magnets 3 are magnetized with the outer S pole and inner N pole, and the other 6 fan-shaped permanent magnets 3 are magnetized with the outer N pole and inner S pole. Figure 5 ,like Figure 5The figure shows a schematic diagram of the magnetization direction of the axially oriented sector-shaped magnetic steel in the circular direction of the built-in permanent magnet generating device of an embodiment of the present application, wherein the sector-shaped permanent magnet 3 with a magnetizing direction of outer S and inner N pole is adjacent to the permanent magnet ring 2 with outer S and inner N pole, and the distance d between the permanent magnet ring and the sector-shaped blade is 10mm, the sector-shaped permanent magnet 3 with outer N and inner S pole and the permanent magnet ring 2 with outer N and inner S pole are located at the other end, the inner diameter of the axially oriented sector-shaped magnetic steel 3 in the circular direction is Rmid=61mm, the outer diameter is the same as the outer diameter of the permanent magnet ring 2, the thickness is h2=42mm, the sector angle is Angle-mag=34°, the angle between the two sector-shaped magnetic steels is Angle-slot=26°, and the distance between the two sector-shaped magnetic steels with opposite magnetizing directions is h3=36mm. The density of the selected permanent magnet is about 8.3g / cm^2, from which it can be seen that the weight of the two permanent magnet rings 2 is about 14.4kg, the total weight of the fan-shaped magnets is about 4.8kg, and the total magnet weight of the permanent magnet generating device is about 19.2kg.

[0037] In this embodiment, the outer radius of the two permanent magnet rings 2 and the sector permanent magnet 3 is the same, and the inner radius of the two permanent magnet rings 2 is the same and is less than or equal to the inner radius of the anode of the relativistic magnetron. The inner radius of the sector permanent magnet 3 is smaller than the inner radius of the anode vane 5, and the opening angle of the sector permanent magnet 3 is smaller than the opening angle of the anode vane 5 of the relativistic magnetron.

[0038] In this embodiment, the outer yoke 4 is made of pure iron material with good magnetic conductivity, and its outer diameter is Riron=97mm and its inner diameter is Rout=87mm. The outer yoke 4 is arranged outside the permanent magnet ring 2 and the sector permanent magnet 3, and its inner radius is the same as the outer radius of the permanent magnet ring 2 and the sector permanent magnet 3, and the outer radius is stuck to the outer wall of the relativistic magnetron outer tube 1. The permanent magnet ring 2, the sector permanent magnet 3 and the outer yoke 4 are fixed by insulating glue.

[0039] In this structural form, the magnetic field distribution on the central axis of the permanent magnet magnetic circuit system is as follows: Figure 6 As shown, it can be seen that the magnetic field size at the center of the uniform zone is about 0.3065T, the magnetic field uniformity is ±0.69%, and the length of the uniform zone is 119mm. Figure 7 ,like Figure 7 The figure shows the radial magnetic field distribution at the center of the built-in permanent magnet generating device of the embodiment of the present application. It can be seen that within the radial direction of 0mm to 40mm, the magnetic field size is between 0.30807T and 0.31305T, and the magnetic field uniformity is ±0.4%, which can effectively cover the electron-field interaction interval 7 in the microwave source, where the interaction interval 7 refers to the interaction interval between the anode and the emission cathode 6 of the relativistic magnetron, meeting the requirements of the working area of ​​the relativistic magnetron.

[0040] The built-in permanent magnet generator for the relativistic magnetron designed in this embodiment is embedded in the relativistic magnetron, making full use of the structural characteristics of the anode of the relativistic magnetron and the space at both ends of the anode, replacing the internal structure of the anode blade of the relativistic magnetron with a fan-shaped magnetic steel, without increasing the lateral size of the system, effectively reducing the overall volume and weight of the permanent magnet relativistic magnetron, reducing the demand for magnetic steel, improving the light and miniaturization level of the system, and having the characteristics of a long and stable uniform magnetic field in the working area; the pole shoe design outside the magnetic steel guides the external magnetic lines through the pole shoe, effectively reducing the external stray magnetic field; the introduction of the internal fan-shaped magnetic steel improves the uniformity of the axial magnetic field in the working area. The built-in permanent magnet generator of the present invention can provide a relatively uniform working magnetic field for the relativistic magnetron for a long time and stably, meeting the required guidance magnetic field requirements when it is working.

[0041] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A built-in permanent magnet generating device, characterized in that: The device is built inside a relativistic magnetron, and comprises: Internal magnetic steel, the internal magnetic steel comprising a first permanent magnetic ring and a second permanent magnetic ring with radial orientation in the magnetization direction, and a plurality of sector-shaped permanent magnetic blocks with radial orientation in the magnetization direction, the sector-shaped permanent magnetic blocks being embedded inside the anode blade of the relativistic magnetron; The peripheral yoke is arranged between the internal magnetic steel and the outer wall of the relativistic magnetron.

2. The built-in permanent magnet generating device according to claim 1, characterized in that: The first permanent magnetic ring and the second permanent magnetic ring are respectively located at two ends of the anode of the relativistic magnetron and have opposite magnetization directions.

3. The built-in permanent magnet generating device according to claim 2, characterized in that: One half of the sector-shaped permanent magnet block is close to the first permanent magnet ring and has the same magnetization direction as the first permanent magnet ring, and the other half of the sector-shaped permanent magnet block is close to the second permanent magnet ring and has the same magnetization direction as the second permanent magnet ring.

4. The built-in permanent magnet generating device according to claim 1, characterized in that: The inner radius of the first permanent magnet ring and the second permanent magnet ring is the same and is less than or equal to the inner radius of the anode of the relativistic magnetron, the inner radius of the fan-shaped permanent magnet block is smaller than the inner radius of the anode blade of the relativistic magnetron, and the opening angle of the fan-shaped permanent magnet block is smaller than the opening angle of the anode blade of the relativistic magnetron.

5. The built-in permanent magnet generating device according to claim 1, characterized in that: The inner radius of the outer yoke is the same as the outer radius of the first permanent magnet ring and the second permanent magnet ring, and the outer radius is smaller than the outer wall of the outer tube of the relativistic magnetron.

6. The built-in permanent magnet generating device according to claim 1, characterized in that: The internal magnetic steel is made of samarium cobalt permanent magnet and processed into a tile-shaped magnet.

7. The internal permanent magnet generating device according to claim 6, characterized in that: The first permanent magnet ring, the second permanent magnet ring and the sector-shaped permanent magnet are formed by magnetizing and bonding the tile-shaped magnets.

8. The built-in permanent magnet generating device according to claim 1, characterized in that: The first permanent magnet ring, the second permanent magnet ring and the sector-shaped permanent magnet are bonded and fixed to the peripheral yoke iron by means of insulating glue.

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