Device for testing flicker characteristic of beam current between grids of ion electric thruster

Abstract

The invention relates to the technical field of electric propulsion, in particular to an ion electric thruster inter-grid beam flicker characteristic testing device which comprises a vacuum testing system, an ion thruster, a neutralizer, a high-speed camera, a high-speed oscilloscope and a gas supply system. A second observation window is arranged at the bottom end; the ion thruster is located at the intersection of the observation view fields of the first observation window and the second observation window. The neutralizer is located above the ion thruster grid system; the first high-speed camera is fixed at the first observation window, and the second high-speed camera is fixed at the second observation window; the high-speed oscilloscope is connected with the high-speed camera and the ion thruster. And the gas supply system is connected with the ion thruster. According to the invention, the optical evolution characteristic of the flicker between the grids can be monitored, the specific position where the beam flicker occurs can be judged, and the problem that the optical characteristic of the beam flicker between the grids of the ion thruster cannot be monitored at a small interval is solved.

Description

Technical Field

[0001] The present application relates to the field of electric propulsion technology, and in particular to a device for testing the inter-grid beam flicker characteristics of an ion electric thruster. Background Art

[0002] Ion electric thruster is an advanced space propulsion technology that converts electrical energy into kinetic energy. Its working principle is to ionize the neutral gas working fluid into plasma, and then use electrostatic acceleration through the gate to accelerate the charged ions and eject them to generate thrust.

[0003] Ion thrusters experience unstable states such as discharge oscillations and ion beam disturbances during operation, and the plasma itself exhibits irreversible random disturbances. When these disturbances exceed a critical value, the beam transitions from a macroscopically stable state to an unstable state, known as beam flicker. This is manifested physically as a momentary arc discharge, occurring in the complex plasma-neutral gas environment and the strong electric field between the grids. Beam flicker can affect the thruster's stable operation, and severe beam flicker can even cause the thruster beam to extinguish, impacting the satellite's propulsion mission.

[0004] Monitoring the optical and electrical properties of beam scintillation is the key to suppressing it. The time from beam scintillation generation to annihilation is very short (the time of a single scintillation is between nanoseconds and milliseconds), and the grid spacing is very small (~0.5mm), making its optical and electrical properties difficult to observe and monitor. Existing thrusters do not have the conditions for direct measurement, and the test methods and means cannot meet the requirements for high-precision monitoring of beam scintillation characteristics. Summary of the Invention

[0005] The present application provides a device for testing the flicker characteristics of beam current between grids of an ion thruster, which solves the problem that the optical characteristics of beam current flicker between grids of an ion thruster cannot be monitored at a small spacing and that high-performance and high-resolution cameras cannot operate under vacuum conditions.

[0006] To achieve the above-mentioned objectives, the present application provides an apparatus for testing the inter-grid beam scintillation characteristics of an ion electric thruster, comprising a vacuum testing system, an ion thruster, a neutralizer, a high-speed camera, a high-speed oscilloscope, and a gas supply system, wherein: a first observation window is provided at the front end of the vacuum testing system, and a second observation window is provided at the bottom end; the ion thruster is disposed within the vacuum testing system, located at the intersection of the observation fields of the first observation window and the second observation window; the neutralizer is disposed within the vacuum testing system, located above the ion thruster grid system; the high-speed cameras are disposed outside the vacuum testing system, and include a first high-speed camera and a second high-speed camera, the first high-speed camera being fixed to the first observation window, and the second high-speed camera being fixed to the second observation window; the high-speed oscilloscope is disposed outside the vacuum testing system, and is connected to the high-speed cameras and the screen grid and acceleration grid of the ion thruster, respectively; and the gas supply system is disposed outside the vacuum testing system, and is connected to the discharge chamber of the ion thruster.

[0007] Furthermore, the ion thruster is a radio frequency ion thruster without an external magnetic field, and its shell is made of transparent quartz glass material.

[0008] Furthermore, the grid plane of the ion thruster and the gap between the grids are both located within the field of view of the high-speed camera.

[0009] Furthermore, it also includes a power supply system, which is connected to the ion thruster, the neutralizer and the high-speed oscilloscope respectively.

[0010] Furthermore, the high-speed oscilloscope is connected to the first high-speed camera and the second high-speed camera respectively through BNC signal synchronization trigger lines.

[0011] Furthermore, the high-speed oscilloscope has a channel number greater than 4, a sampling frequency greater than 1 GHz, and a bandwidth greater than or equal to 200 MHz.

[0012] Furthermore, the frame rate of the high-speed camera is ≥ 1 million frames.

[0013] The present application provides a device for testing the inter-grid beam flicker characteristics of an ion electric thruster, which has the following beneficial effects:

[0014] This application adopts a radio frequency ion thruster with a simple structure and no external magnetic field, replacing the traditional metal shell with a transparent quartz glass material to ensure the normal and long-term stable operation of the thruster; a high-speed camera can be used to directly obtain the optical characteristics of the beam scintillation between the grids, which can not only monitor the optical evolution characteristics of the scintillation between the grids but also determine the specific location where the beam scintillation occurs, solving the problem of being unable to monitor the optical characteristics of the beam scintillation between the grids of the ion thruster at a small spacing (0.5mm); and also solving the problem of high-performance and high-resolution cameras being unable to work under vacuum conditions, greatly improving the resolution and accuracy of beam scintillation characteristic monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] 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:

[0016] Figure 1 Schematic diagram of an apparatus for testing beam flicker characteristics between grids of an ion electric thruster according to an embodiment of the present application;

[0017] In the figure: 1-vacuum test system, 2-neutralizer, 3-first observation window, 4-first high-speed camera, 5-BNC signal synchronization trigger line, 6-second observation window, 7-second high-speed camera, 8-ion thruster, 9-gas supply system, 10-power supply system, 11-high-speed oscilloscope. DETAILED DESCRIPTION

[0018] 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.

[0019] 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 here. 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.

[0020] 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.

[0021] 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.

[0022] Additionally, the term "plurality" shall mean two or more.

[0023] 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.

[0024] like Figure 1 As shown, the present application provides an apparatus for testing beam scintillation characteristics between grids of an ion electric thruster, comprising a vacuum testing system 1, an ion thruster 8, a neutralizer 2, a high-speed camera, a high-speed oscilloscope 11, and a gas supply system 9, wherein: a first observation window 3 is provided at the front end of the vacuum testing system 1, and a second observation window 6 is provided at the bottom end; the ion thruster 8 is arranged inside the vacuum testing system 1, at the intersection of the observation fields of the first observation window 3 and the second observation window 6; the neutralizer 2 is arranged inside the vacuum testing system 1, above the grid system of the ion thruster 8; the high-speed camera is arranged outside the vacuum testing system 1, and comprises a first high-speed camera 4 and a second high-speed camera 7, wherein the first high-speed camera 4 is fixed to the first observation window 3, and the second high-speed camera 7 is fixed to the second observation window 6; the high-speed oscilloscope 11 is arranged outside the vacuum testing system 1, and is respectively connected to the high-speed camera and the screen grid and acceleration grid of the ion thruster 8; and the gas supply system 9 is arranged outside the vacuum testing system 1, and is connected to the discharge chamber of the ion thruster 8.

[0025] Specifically, the ion electric thruster inter-grid beam flicker characteristic test device provided in the embodiment of the present application is mainly used to monitor the optical evolution characteristics of the inter-grid flicker of the ion thruster 8 and determine the specific location where the beam flicker occurs. The vacuum test system 1 is used to provide a vacuum environment for the ion thruster 8 test operation. The vacuum test system 1 is composed of a vacuum chamber as a whole. Glass observation windows are provided in front and below the vacuum chamber for observing the working status of the internal ion thruster 8. The ion thruster 8 is located inside the vacuum chamber and is set at the intersection of the fields of view of the two glass observation windows. The neutralizer 2 is used to neutralize the charge and optimize the focusing of the ion beam. The high-speed camera is mainly used to shoot and record the characteristic features of the beam flicker. Preferably, two high-speed cameras are provided, which are respectively provided at the first observation window 3 and the second observation window 6. The first high-speed camera 4 and the first observation window 3 are mainly used to observe and shoot the grid of the ion thruster 8. The second high-speed camera 7 and the second observation window 6 are mainly used to observe and photograph the characteristics of the grid gap of the ion thruster 8; the high-speed oscilloscope 11 is respectively connected to the high-speed camera and the screen grid and acceleration grid of the ion thruster 8. When the high-speed oscilloscope 11 detects a sudden change in the grid current / voltage signal of the ion thruster 8, the high-speed oscilloscope 11 records and saves the electrical characteristics of the beam scintillation and synchronously triggers the high-speed camera to take pictures, record and save the characteristics of the beam scintillation; the gas supply system 9 is connected to the discharge chamber of the ion thruster 8 to provide the working fluid gas required for ionization, preferably xenon.

[0026] Furthermore, the ion thruster 8 is a radio frequency ion thruster 8 without an external magnetic field, and its shell is made of transparent quartz glass material.

[0027] Furthermore, the grid planes of the ion thruster 8 and the gaps between the grids are both located within the field of view of the high-speed camera.

[0028] Specifically, the ion thruster 8 is a radio frequency ion thruster 8 with a simple structure and no external magnetic field. The thruster shell is made of transparent quartz glass material to ensure that the small gap (0.5mm) between the grids of the ion thruster 8 and the entire grid plane are within the field of view of the high-speed camera, so that the position of the beam scintillation can be located and the electrical characteristics and optical evolution characteristics of the beam scintillation can be clearly recorded.

[0029] Furthermore, a power supply system 10 is included, which is connected to the ion thruster 8, the neutralizer 2, and the high-speed oscilloscope 11. The power supply system 10 is used to provide the discharge chamber and grid system of the ion thruster 8, the neutralizer 2, and the high-speed oscilloscope 11 with the electrical energy required for operation.

[0030] Furthermore, the high-speed oscilloscope 11 is connected to the first high-speed camera 4 and the second high-speed camera 7 respectively through the BNC signal synchronization trigger line 5 .

[0031] Furthermore, the high-speed oscilloscope 11 has a channel number greater than 4, a sampling frequency greater than 1 GHz, and a bandwidth greater than or equal to 200 MHz.

[0032] Specifically, the high-speed oscilloscope 11 is connected to the screen grid and acceleration grid of the ion thruster 8 on one hand, and synchronously monitors the voltage and current signals of the two grids; on the other hand, it is connected to the first high-speed camera 4 and the second high-speed camera 7 through the BNC signal synchronization trigger line 5, and is connected in series triggering mode. That is, when the high-speed oscilloscope 11 detects a sudden change in the grid current / voltage signal of the ion thruster 8, it will synchronously trigger the high-speed camera to take pictures, record and save the characteristic features of the beam flicker.

[0033] Furthermore, the frame rate of the high-speed camera is ≥1 million frames. Two high-speed cameras can be used to directly obtain the optical characteristics of beam scintillation between the grids of the ion thruster 8. The high-speed cameras are set outside the vacuum test system 1 to ensure that the entire process of beam scintillation can be captured, thereby improving the resolution and accuracy of beam scintillation characteristic monitoring, and solving the problem that high-performance and high-resolution cameras cannot work under vacuum conditions.

[0034] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. 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 device for testing the beam flicker characteristics between grids of an ion electric thruster, characterized in that: It includes a vacuum test system, an ion thruster, a neutralizer, a high-speed camera, a high-speed oscilloscope, and a gas supply system, including: The vacuum testing system is provided with a first observation window at the front end and a second observation window at the bottom end; The ion thruster is arranged inside the vacuum testing system, at the intersection of the observation fields of the first observation window and the second observation window; The neutralizer is arranged inside the vacuum testing system and above the ion thruster grid system; The high-speed camera is arranged outside the vacuum testing system, and includes a first high-speed camera and a second high-speed camera, wherein the first high-speed camera is fixed at the first observation window, and the second high-speed camera is fixed at the second observation window; The high-speed oscilloscope is arranged outside the vacuum testing system and is respectively connected to the high-speed camera and the screen grid and the acceleration grid of the ion thruster; The gas supply system is arranged outside the vacuum testing system and connected to the discharge chamber of the ion thruster.

2. The device for testing beam flicker characteristics between grids of an ion electric thruster according to claim 1, characterized in that: The ion thruster is a radio frequency ion thruster without an external magnetic field, and its shell is made of transparent quartz glass material.

3. The device for testing beam flicker characteristics between grids of an ion electric thruster according to claim 2, characterized in that: The grid plane of the ion thruster and the gaps between the grids are both located within the field of view of the high-speed camera.

4. The device for testing beam flicker characteristics between grids of an ion electric thruster according to claim 3, characterized in that: It also includes a power supply system, which is connected to the ion thruster, the neutralizer and the high-speed oscilloscope respectively.

5. The device for testing beam flicker characteristics between grids of an ion electric thruster according to claim 4, characterized in that: The high-speed oscilloscope is connected to the first high-speed camera and the second high-speed camera respectively through BNC signal synchronization trigger lines.

6. The device for testing beam flicker characteristics between grids of an ion electric thruster according to claim 5, characterized in that: The high-speed oscilloscope has a channel number greater than 4, a sampling frequency greater than 1 GHz, and a bandwidth greater than or equal to 200 MHz.

7. The device for testing beam flicker characteristics between grids of an ion electric thruster according to claim 6, characterized in that: The frame rate of the high-speed camera is ≥1 million frames.

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