A divergent field plasma source grid assembly

Abstract

The present application relates to the field of spacecraft technology, and more specifically, to a divergent field plasma source grid assembly, comprising a grid mounting ring, a ceramic ring, an insulating assembly, and a grid, wherein: the grid mounting ring, the ceramic ring, and the grid are all annular boss structures; the grid is fixed to the grid mounting ring through an insulating assembly; the ceramic ring is arranged between the grid mounting ring and the grid; the grid mounting ring, the ceramic ring, and the grid are coaxially mounted. The present application achieves an insulated grid installation by providing a ceramic ring and an insulating assembly, and can switch the plasma source operating mode by changing the grid potential according to the satellite's electrification status, thereby more accurately and quickly controlling the satellite potential; compared to traditional divergent field ion thruster grid assemblies, the grid is not only insulated, but the bolts connecting and fixing the grid are installed outside the discharge chamber to prevent the bolt assembly from being sputtered inside the discharge chamber, which would cause contamination of components such as the grid and cathode, and damage to the bolt threads due to sputtering, making replacement difficult.

Description

Technical Field

[0001] The present application relates to the field of spacecraft technology, and in particular to a divergent field plasma source grid assembly. Background Art

[0002] While in orbit, spacecraft are subject to the effects of the space environment, causing them to become charged. The resulting electrostatic charge and discharge can cause spacecraft failures and significant losses. In the space plasma environment, the potential on a spacecraft's surface is non-uniform and dynamically changes over time. When the surface charge potential reaches the discharge threshold, the resulting space electrostatic discharge can cause spacecraft failure. The widespread use of new multifunctional spacecraft has made the issue of spacecraft charge and discharge particularly prominent. Therefore, research on active surface potential control technology is crucial for ensuring safe and stable spacecraft operation.

[0003] Spacecraft surfaces exposed to sunlight are generally charged to a low positive potential, while insulating surfaces in the dark may be charged to a negative voltage of around 10kV. This high-voltage static charge is prone to arcing. Passive protection methods such as anti-static coatings and shielding are commonly used to complete satellite development missions. However, the impact of charging and discharging on satellites, especially those in medium and high orbits, is becoming increasingly prominent. The electromagnetic interference generated by satellite charging and discharging is particularly noticeable on communications satellites.

[0004] The SCATHA satellite, launched by the United States in 1979, was equipped with three active potential control devices: an electron gun and a hot filament capable of emitting thermal electrons, as well as a plasma emitter capable of emitting Xe ions alone or a mixture of Xe ions and low-energy electrons. Tests showed that emitting charged particle beams could effectively discharge or neutralize charges accumulated on the satellite's surface. In 1995, the DSCS-III satellite conducted in-orbit verification tests of active potential control technology using xenon plasma. The results showed that emitting a low-energy plasma beam from the satellite was more effective in discharging charges accumulated on the satellite's surface than emitting ion or electron beams alone. The polar-orbiting Polar satellite, launched in 1996, effectively controlled the satellite's structural potential using a PSI. Using xenon as the working fluid, PSI ionizes xenon to form a medium-concentration plasma, which is then ejected to establish a path for free charge movement between the satellite surface and the ambient plasma—a plasma bridge. The above-mentioned foreign satellite in-orbit applications show that the plasma launch device can effectively control the satellite potential, and the grid assembly is the core component of the plasma source launch device. Therefore, it is necessary to develop a divergent field plasma source grid assembly to accurately and quickly control the satellite potential. Summary of the Invention

[0005] The present application provides a divergent field plasma source grid assembly, which realizes grid insulation installation through the connection of insulating components.

[0006] In order to achieve the above-mentioned purpose, the present application provides a divergent field plasma source gate assembly, including a gate mounting ring, a ceramic ring, an insulating assembly and a gate, wherein: the gate mounting ring, the ceramic ring and the gate are all annular boss structures; the gate is fixed to the gate mounting ring through the insulating assembly; the ceramic ring is arranged between the gate mounting ring and the gate; the gate mounting ring, the ceramic ring and the gate are coaxially mounted.

[0007] Furthermore, the gate mounting ring is made of a magnetically conductive material for confining the magnetic field of the plasma source.

[0008] Furthermore, a first connection hole and a first fixing hole are provided on the grid mounting ring, wherein: the first connection hole is used to connect with the divergent field plasma source discharge chamber; the first fixing hole is used to cooperate with the insulating component for connection.

[0009] Furthermore, the ceramic ring is an integrally formed ceramic structure, provided with a second connecting hole and a second fixing hole, wherein: the second connecting hole is provided corresponding to the first connecting hole for connection with an external structure; the second fixing hole is provided corresponding to the first fixing hole for connection with an insulating component.

[0010] Furthermore, the grid is made of carbon fiber material and includes a grid hole portion and a supporting and fixing portion, and the grid hole portion and the supporting and fixing portion are an integrated structure.

[0011] Furthermore, a plurality of lead-out holes are evenly distributed on the grid hole portion, and a third connection hole and a third fixing hole are provided on the supporting fixing portion, wherein: the thickness of the grid hole portion is 0.3-1 mm; the lead-out hole is used to lead out electrons or ions; the third connection hole is provided corresponding to the first connection hole for connecting to an external structure; the third fixing hole is provided corresponding to the second fixing hole for cooperating with the insulating component for connection.

[0012] Furthermore, the insulating assembly includes a ceramic insulator, a protective cover and bolts, which pass through the third fixing hole, the second fixing hole and the first fixing hole in sequence to fix the ceramic insulator and the protective cover above the gate, between the gate and the ceramic ring, and below the gate mounting ring, respectively.

[0013] Furthermore, the operating mode of the divergent field plasma source is switched by changing the potential of the gate.

[0014] The present invention provides a divergent field plasma source grid assembly, which has the following beneficial effects:

[0015] The present application realizes the insulated installation of the grid by setting a ceramic ring and an insulating component. The potential of the grid can be changed to switch the plasma source working condition according to the charging condition of the satellite, thereby controlling the satellite potential more accurately and quickly. Compared with the traditional divergent field ion thruster grid assembly, the grid is not only insulated, but the bolts for fixing the grid are also installed outside the discharge chamber to prevent the bolt assembly from being sputtered inside the discharge chamber, which would cause contamination of parts such as the grid and cathode and sputtering damage to the bolt threads, making replacement difficult. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings that constitute part of this application are used to provide a further understanding of this application and make other features, objects and advantages of this application more apparent. The illustrative embodiment drawings of this application and their descriptions are used to explain this application and do not constitute an improper limitation of this application. In the drawings:

[0017] Figure 1 Schematic diagram of a divergent field plasma source grid assembly provided according to an embodiment of the present application;

[0018] Figure 2 Schematic diagram of a grid of a divergent field plasma source grid assembly provided according to an embodiment of the present application;

[0019] Figure 3 Schematic diagram of a ceramic ring of a divergent field plasma source grid assembly provided according to an embodiment of the present application;

[0020] In the figure: 1-gate mounting ring, 2-ceramic ring, 21-second connection hole, 22-second fixing hole, 3-insulating component, 4-gate, 41-lead-out hole, 42-third connection hole, 43-third fixing hole. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of this application.

[0022] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0023] In this application, terms such as "upper," "lower," "left," "right," "front," "back," "top," "bottom," "inner," "outer," "center," "vertical," "horizontal," "transverse," and "longitudinal" indicate positions or locations based on the positions or locations shown in the accompanying drawings. These terms are primarily intended to better describe this application and its embodiments and are not intended to limit the devices, elements, or components indicated to having a specific orientation, or to being constructed or operated in a specific orientation.

[0024] Furthermore, some of the above terms may be used to express other meanings besides indicating a position or location. For example, the term "on" may also be used to indicate a dependency or connection in certain circumstances. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0025] Additionally, the term "plurality" shall mean two or more.

[0026] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0027] like Figure 1 As shown, the present application provides a divergent field plasma source gate assembly, including a gate mounting ring 1, a ceramic ring 2, an insulating assembly 3 and a gate 4, wherein: the gate mounting ring 1, the ceramic ring 2 and the gate 4 are all annular boss structures; the gate 4 is fixed on the gate mounting ring 1 through the insulating assembly 3; the ceramic ring 2 is arranged between the gate mounting ring 1 and the gate 4; the gate mounting ring 1, the ceramic ring 2 and the gate 4 are coaxially mounted.

[0028] Specifically, the gate structure of a conventional divergent field ion thruster grid assembly is generally a split structure, that is, the grid hole portion and the supporting and fixing portion are designed separately, and the insulating connection structure is only provided on the supporting and fixing portion, resulting in relatively poor insulation effect. Moreover, the components connected and fixed thereto are generally arranged inside the discharge chamber, and are easily sputtered after long-term operation, which can lead to contamination of parts such as the grid and cathode. However, the divergent field plasma source grid assembly provided in the embodiment of the present application sets the grid structure as an integrated structure, and sets a ceramic ring 2, which is also an integrated structure, between it and the grid mounting ring 1. In this way, the ceramic ring 2 and the insulating component 3 surrounding the supporting and fixing portion form an insulating structure in the shape of a boss, achieving overall insulation of the grid 4, good insulation effect, and strong operability. In addition, the grid mounting ring 1 is also provided with fixing holes and connection holes, so that the bolts connected to the grid 4 can be installed outside the discharge chamber to prevent the bolt assembly from being sputtered inside the discharge chamber, resulting in contamination of parts such as the grid 4 and the cathode and sputtering damage to the bolt threads, which makes replacement difficult.

[0029] Furthermore, the gate mounting ring 1 is made of a magnetically conductive material for confining the magnetic field of the plasma source.

[0030] Furthermore, a first connection hole and a first fixing hole are provided on the gate mounting ring 1 , wherein: the first connection hole is used to connect with the divergent field plasma source discharge chamber; the first fixing hole is used to cooperate with the insulating component 3 .

[0031] Specifically, the material of the gate mounting ring 1 is a magnetic conductive material used to confine the magnetic field of the plasma source, preferably a material such as 4J29 or 4J33. A plurality of first connection holes are evenly distributed around the gate mounting ring 1. The gate mounting ring 1 is connected to the plasma source discharge chamber through the first connection holes, and is connected to the gate 4 through the cooperation of the first fixing hole and the insulating component 3, so that the gate 4 as a whole can be fixedly connected to the plasma source discharge chamber.

[0032] Further, such as Figure 3 As shown, the ceramic ring 2 is an integrally formed ceramic structure, provided with a second connection hole 21 and a second fixing hole 22. The second connection hole 21 corresponds to the first connection hole and is used for connection to an external structure; the second fixing hole 22 corresponds to the first fixing hole and is used for mating with the insulating assembly 3. The ceramic ring 2 is an integrally formed boss structure, positioned between the gate 4 and the gate mounting ring 1. The second connection hole 21 is used for mating with other external structural components, and the second fixing hole 22 is used to accommodate the insulating assembly 3. The ceramic ring 2 is mated with the insulating assembly 3 to achieve effective insulation of the gate 4.

[0033] Further, such as Figure 2As shown, the grid 4 is made of carbon fiber material and includes a grid hole portion and a supporting and fixing portion, and the grid hole portion and the supporting and fixing portion are an integrated structure.

[0034] Furthermore, a plurality of lead-out holes 41 are evenly distributed on the grid hole portion, and a third connection hole 42 and a third fixing hole 43 are provided on the supporting fixing portion, wherein: the thickness of the grid hole portion is 0.3-1 mm; the lead-out hole 41 is used to lead out electrons or ions; the third connection hole 42 is provided corresponding to the first connection hole for connecting to an external structure; the third fixing hole 43 is provided corresponding to the second fixing hole 22 for cooperating with the insulating component 3 for connection.

[0035] Specifically, the gate 4 is made of a carbon fiber material that is sputter-resistant and exhibits minimal thermal deformation. The central aperture region and the surrounding support and fixing regions are integrally molded, ultimately forming a one-piece structure. The aperture region has a thickness of 0.3-1mm and is uniformly distributed with multiple extraction holes 41 for extracting electrons or ions. The support and fixing portion is provided with a third connection hole 42 and a third fixing hole 43. The third connection hole 42 is used for connecting to other external structural components and also serves to reduce weight. The third fixing hole 43 is also used to accommodate the insulating component 3. The gate 4 is fixed to the gate mounting ring 1 via the insulating component 3.

[0036] Furthermore, the insulating assembly 3 includes a ceramic insulator, a protective cover, and bolts. The bolts pass through the third fixing hole 43, the second fixing hole 22, and the first fixing hole in sequence, fixing the ceramic insulator and the protective cover above the gate 4, between the gate 4 and the ceramic ring 2, and below the gate mounting ring 1, respectively. The insulating assembly 3 is used to connect and insulate the entire gate assembly. The ceramic insulator preferably includes an upper ceramic and a lower ceramic, and the protective cover preferably includes an upper protective cover and a lower protective cover. The bolts pass through the third fixing hole, the upper protective cover, the upper ceramic, the second fixing hole, the first fixing hole, the lower ceramic, and the lower protective cover in sequence from top to bottom, and are finally locked and fixed using gaskets and nuts, thereby fixing the ceramic ring 2 and the gate 4 in sequence above the gate mounting ring 1, and cooperating with the ceramic ring 2 as a whole to achieve insulation of the gate 4.

[0037] Furthermore, the divergent field plasma source operating mode is switched by changing the potential of gate 4. During operation, depending on the actual charging situation, high or low voltage can be applied to gate 4 to change the potential of gate 4, thereby switching the divergent field plasma source operating mode, thereby more accurately and quickly controlling the satellite potential and reducing the impact of charging and discharging effects on the satellite.

[0038] The foregoing description is merely a preferred embodiment of the present application and is not intended to limit the present application. Persons skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A divergent field plasma source grid assembly, characterized in that: It includes a gate mounting ring, a ceramic ring, an insulating component and a gate, wherein: The gate mounting ring, the ceramic ring and the gate are all annular boss structures; The gate is fixed on the gate mounting ring through the insulating component; The ceramic ring is arranged between the gate mounting ring and the gate; The gate mounting ring, the ceramic ring and the gate are coaxially mounted; The gate mounting ring is made of a magnetically conductive material and is used to confine the magnetic field of the plasma source; The insulating assembly includes a ceramic insulating member, a protective cover, and a bolt, wherein the bolt passes through the third fixing hole, the second fixing hole, and the first fixing hole in sequence to fix the ceramic insulating member and the protective cover above the gate, between the gate and the ceramic ring, and below the gate mounting ring, respectively; The working mode of the divergent field plasma source is switched by changing the potential of the grid.

2. The divergent field plasma source grid assembly according to claim 1, characterized in that: The gate mounting ring is provided with a first connection hole and a first fixing hole, wherein: The first connection hole is used to connect to the divergent field plasma source discharge chamber; The first fixing hole is used for being matched and connected with the insulating component.

3. The divergent field plasma source grid assembly according to claim 2, characterized in that: The ceramic ring is an integrally formed ceramic structure and is provided with a second connection hole and a second fixing hole, wherein: The second connection hole is provided corresponding to the first connection hole and is used for connecting to an external structure; The second fixing hole is arranged corresponding to the first fixing hole and is used for being matched with and connected to the insulating component.

4. The divergent field plasma source grid assembly according to claim 3, characterized in that: The grid is made of carbon fiber material and includes a grid hole portion and a supporting and fixing portion, wherein the grid hole portion and the supporting and fixing portion are an integrated structure.

5. The divergent field plasma source grid assembly according to claim 4, characterized in that: The grid hole portion is evenly distributed with a plurality of lead holes, and the support fixing portion is provided with a third connection hole and a third fixing hole, wherein: The thickness of the grid hole portion is 0.3-1 mm; The extraction hole is used to extract electrons or ions; The third connection hole is provided corresponding to the first connection hole and is used for connecting to an external structure; The third fixing hole is arranged corresponding to the second fixing hole and is used for being matched with and connected to the insulating component.

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