On-orbit monitoring device and method for cathode coupling state based on thrust fluctuation

Abstract

The present invention proposes an on-orbit monitoring device and method for cathode coupling state based on thrust fluctuation, belonging to the field of aerospace plasma propulsion technology. A test bench is constructed on the ground and a Faraday probe is used to monitor the plume, combined with a plume imaging method and a thrust frame. A fixed airflow is introduced into the cathode and the thruster, and the voltage or current is adjusted in a manner from small to large to form a test grid. Then, the above operation is repeated with different airflows to obtain a series of coupling zone states and data under different working conditions, and the data are stored in a database to pre-calibrate the thrust of the Hall thruster. During the on-orbit process, the plume imaging method is used to compare the measured data with the database formed by the ground test to determine whether the state of the thruster coupling zone is normal, and then the thruster operation state is determined. The present invention can timely adjust the working state or cut off the current to avoid danger.

Description

Technical Field

[0001] The present invention belongs to the technical field of aerospace plasma propulsion, and in particular, relates to an on-orbit monitoring device and a monitoring method for a cathode coupling state based on thrust fluctuation. Background Art

[0002] Plasma thrusters are a type of electric propulsion device with broad application prospects. They use electrical energy to ionize propellants into plasma and accelerate ions to generate thrust during the discharge process in the channel. This thruster has been used on various satellites, and the related demand is increasing day by day. As a type of electric thruster, Hall thrusters have the characteristics of small size, simple structure, high reliability, and long life. They are widely used in the field of aerospace propulsion. However, during the on-orbit operation of electric thrusters, the monitoring of thrust fluctuations is crucial.

[0003] By monitoring the fluctuation of thrust, the working status of the electric thruster can be inferred and the plume divergence angle can be calculated to avoid excessive contamination of solar panels. Accurate monitoring of thrust fluctuations in the electric propulsion plume can provide important information for the successful implementation of space missions. It not only helps to understand the working status of the thruster, but also helps to optimize the performance of the propulsion system and improve the accuracy and stability of the mission.

[0004] The electric probe method is one of the important means to evaluate and analyze the thrust fluctuation of plasma thrusters. It uses an electric probe as a direct contact test tool to quickly measure the plume state of the Hall thruster. The electric probe has the characteristics of short response time. The thrust stand can directly measure the thrust characteristics of the thruster and is widely used in the measurement of various electric thruster inferences. In addition, the plume imaging method is widely used to monitor the plume morphology due to its unique non-direct contact characteristics to directly feedback the corresponding working condition information. These methods play an important role in evaluating and analyzing the thrust fluctuation of plasma thrusters.

[0005] However, the existing methods lack the means to monitor the coupling status of the Hall thruster and the hollow cathode in real time, and it is difficult to adjust the operating conditions in time when problems occur with the thruster while in orbit. Summary of the invention

[0006] In response to the above problems, the present invention proposes an on-orbit monitoring device and method for the cathode coupling state based on thrust fluctuations. The method can determine the state of the process that affects the coupling between the hollow cathode and the thruster when the performance of the Hall thruster is attenuated, so that its on-orbit operation can be timely adjusted according to the provided method, and when the current of the thruster fluctuates, the working state can be timely adjusted or the current can be cut off to avoid danger.

[0007] The present invention is achieved through the following technical solutions:

[0008] On-orbit monitoring device for cathode coupling status based on thrust fluctuation:

[0009] The on-orbit monitoring device includes a Faraday probe, a multispectral camera, a hollow cathode, a Hall thruster, an air supply unit, a thrust frame, a vacuum tank, a first power supply and a second power supply;

[0010] The Faraday probe is used to measure the plume divergence angle and ion current of the Hall thruster;

[0011] The multispectral camera is located outside the vacuum tank and is used to take images of the plume from the Hall thruster:

[0012] The hollow cathode generates ionized plasma by ionizing the working fluid gas;

[0013] The Hall thruster uses electromagnetic fields to accelerate ions and generate thrust;

[0014] The gas supply unit is used to deliver working gas to the Hall thruster and the hollow cathode.

[0015] The thrust frame is responsible for supporting the Hall thruster and measuring the thrust generated by the Hall thruster;

[0016] The vacuum tank provides a certain vacuum environment for the experiment; the Faraday probe, the hollow cathode, the Hall thruster and the thrust frame are all inside the vacuum tank;

[0017] The first power supply and the second power supply provide the required electrical energy to the hollow cathode and the Hall thruster respectively.

[0018] Monitoring method of cathode coupling state on-orbit monitoring device based on thrust fluctuation:

[0019] The method specifically includes on-ground construction and on-orbit monitoring;

[0020] On the ground, the coupling state of the Hall thruster and the hollow cathode is pre-calibrated by the on-orbit monitoring device through a thruster of a given design:

[0021] When in orbit, the plume of the Hall thruster is photographed and uploaded to the terminal for comparison with the pre-calibrated coupling state of the Hall thruster and hollow cathode in the database obtained on the ground. The operating condition of the Hall thruster is adjusted until it matches the ground condition to complete the on-orbit monitoring.

[0022] Furthermore, the on-site construction specifically includes the following steps:

[0023] Step 1: Pump the vacuum tank until the pressure drops to 10 -3 Below Pa;

[0024] Step 2: Start the gas supply unit to provide a certain flow rate of working gas to the hollow cathode and the Hall thruster, and start the first power supply and the second power supply to provide a certain voltage to the hollow cathode and the Hall thruster to ignite the hollow cathode and the Hall thruster;

[0025] Step 3: When the plume is stable, the multispectral camera is turned on to take pictures of the plume of the stably operating Hall thruster and upload them to the database;

[0026] Step 4: After the plume is stable, the data such as the plume divergence angle and ion current measured by the Faraday probe are transmitted to the database;

[0027] Step 5: After the Hall thruster is stabilized, the thrust of the Hall thruster is measured using a thrust frame and the measurement results are uploaded to the database;

[0028] Step 6, calibrating the coupling state of the Hall thruster and the hollow cathode at this time as the standard;

[0029] Step seven, repeat steps one to six to pre-calibrate the coupling state of the Hall thruster and the hollow cathode under different working thrust conditions.

[0030] Furthermore, in step one, before evacuating the vacuum tank, the thrust frame is debugged; the mass of the required counterweight is estimated, and the number of counterweights to be installed within the mass range is selected.

[0031] An electronic device comprises a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above method when executing the computer program.

[0032] A computer-readable storage medium is used to store computer instructions, and when the computer instructions are executed by a processor, the steps of the above method are implemented.

[0033] Beneficial effects of the present invention

[0034] The present invention uses a camera device, a probe, and a thrust frame to calibrate the coupling state of the thruster and the hollow cathode under different working conditions of the Hall thruster, stores the obtained data in a database, and compares the data with the plume parameters obtained when the thruster is on orbit to obtain the coupling state when the thruster is on orbit.

[0035] The present invention performs pre-calibration on the ground and monitors the plume image in real time on orbit, so as to timely discover and adjust the working status of the Hall thruster, thereby improving the stability and performance of the propulsion system. Compared with traditional methods, the present invention has the advantages of high degree of automation, time and labor saving, accurate test data, high integration and high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 The figure is a flow chart of the method of the present invention.

[0037] Figure 2 A schematic diagram of an experimental device for monitoring the coupling state of the Hall thruster and the cathode of the present invention.

[0038] Among them are Faraday probe-1, multispectral camera-2, hollow cathode-3, Hall thruster-4, air supply unit-5, thrust frame-6, vacuum tank-7, first power supply-8, and second power supply-9. DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the present invention will be described clearly and completely below 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 of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] Combination Figure 1 and Figure 2 The present invention uses a Faraday probe to monitor the plume on the ground test bench, combined with a plume imaging method and a thrust frame, and passes a fixed airflow through the cathode and the thruster, and adjusts the voltage or current from small to large to form a test grid. Then, the above operation is repeated with different airflows to obtain a series of coupling zone states and data under different working conditions, and the data is stored in the database to pre-calibrate the thrust of the Hall thruster. During the on-orbit process, the plume imaging method is used to compare the measured data with the database formed by the ground test to determine whether the state of the thruster coupling zone is normal, and then determine the thruster operation state.

[0041] Embodiments of the present invention are as follows:

[0042] On-orbit monitoring device for cathode coupling status based on thrust fluctuation:

[0043] The on-orbit monitoring device includes a Faraday probe 1, a multispectral camera 2, a hollow cathode 3, a Hall thruster 4, an air supply unit 5, a thrust frame 6, a vacuum tank 7, a first power supply 8 and a second power supply 9;

[0044] The Faraday probe 1 is used to measure the plume divergence angle and ion current of the Hall thruster 4;

[0045] The multispectral camera 2 is located outside the vacuum tank 7 and is used to capture the plume image of the Hall thruster: spectral components of different wavelengths correspond to different plasma components. The multispectral camera can provide more detailed plasma plume information to help analyze and evaluate the working status of the thruster.

[0046] The hollow cathode 3 generates ionized plasma by ionizing the working fluid gas;

[0047] The Hall thruster 4 uses an electromagnetic field to accelerate ions and generate thrust;

[0048] The gas supply unit 5 is used to deliver working gas to the Hall thruster 4 and the hollow cathode 3 to maintain the generation of plasma and the operation of the thruster;

[0049] The thrust frame 6 is responsible for supporting the Hall thruster 4 and measuring the thrust generated by it;

[0050] The vacuum tank 7 provides a certain vacuum environment for the experiment; the Faraday probe 1, the hollow cathode 3, the Hall thruster 4 and the thrust frame 6 are all inside the vacuum tank 7;

[0051] The first power source 8 and the second power source 9 provide the required electrical energy to the hollow cathode 3 and the Hall thruster 4 respectively.

[0052] Monitoring method of cathode coupling state on-orbit monitoring device based on thrust fluctuation:

[0053] The method specifically includes on-ground construction and on-orbit monitoring;

[0054] On the ground, the coupling state of the Hall thruster 4 and the hollow cathode 3 is pre-calibrated by the on-orbit monitoring device through a thruster of a given design:

[0055] The on-site construction specifically includes the following steps:

[0056] Step 1: evacuate the vacuum tank 7 until the pressure drops to 10 -3 Below Pa;

[0057] In step 1, before evacuating the vacuum tank 7, the thrust frame 6 is debugged; the mass of the required counterweight is estimated, and the number of counterweights to be installed within the mass range is selected.

[0058] Step 2: Start the gas supply unit 5 to provide a certain flow rate of working gas to the hollow cathode 3 and the Hall thruster 4, and start the first power supply 8 and the second power supply 9 to provide a certain voltage to the hollow cathode 3 and the Hall thruster 4 to ignite the hollow cathode 3 and the Hall thruster 4;

[0059] Step 3: When the plume is stable, the multispectral camera 2 is turned on to take pictures of the plume of the stably operating Hall thruster 4 and upload them to the database;

[0060] Step 4: after the plume is stable, the data such as the plume divergence angle and ion current measured by the Faraday probe 1 are transmitted to the database;

[0061] Step 5: After the Hall thruster 4 is stabilized, the thrust frame 6 is used to measure the thrust of the Hall thruster 4 and the measurement result is uploaded to the database;

[0062] Step 6, calibrating the coupling state of the Hall thruster 4 and the hollow cathode 3 at this time as a standard;

[0063] Step 7, repeat steps 1 to 6 to pre-calibrate the coupling state of the Hall thruster 4 and the hollow cathode 3 under different working thrust conditions.

[0064] When in orbit, the plume of the Hall thruster 4 is photographed and uploaded to the terminal for comparison with the pre-calibrated coupling state of the Hall thruster 4 and the hollow cathode 3 in the database obtained on the ground. The working condition of the Hall thruster 4 is adjusted until it matches the ground state to complete the on-orbit monitoring.

[0065] An electronic device comprises a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above method when executing the computer program.

[0066] A computer-readable storage medium is used to store computer instructions, and when the computer instructions are executed by a processor, the steps of the above method are implemented.

[0067] The memory in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory, ROM, a programmable read-only memory, PROM, an erasable programmable read-only memory, EPROM, an electrically erasable programmable read-only memory, EEPROM, or a flash memory. The volatile memory may be a random access memory, RAM, which is used as an external cache. By way of example but not limitation, many forms of RAM are available, such as static random access memory static RAM, SRAM, dynamic random access memory dynamic RAM, DRAM, synchronous dynamic random access memory synchronous DRAM, SDRAM, double data rate synchronous dynamic random access memory double data rate SDRAM, DDR SDRAM, enhanced synchronous dynamic random access memory enhanced SDRAM, ESDRAM, synchronous connection dynamic random access memory synchlink DRAM, SLDRAM and direct memory bus random access memory direct rambus RAM, DR RAM. It should be noted that memory of the methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0068] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website site, computer, server or data center through a wired method such as coaxial cable, optical fiber, digital subscriber line digital subscriber line, DSL or wireless such as infrared, wireless, microwave, etc. to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or data center that includes one or more available media integrated. The available medium can be a magnetic medium such as a floppy disk, a hard disk, a tape, an optical medium such as a high-density digital video disc digital video disc, DVD, or a semiconductor medium such as a solid state hard disk solid state disc, SSD, etc.

[0069] In the implementation process, each step of the above method can be completed by an integrated logic circuit of hardware in a processor or an instruction in the form of software. The steps of the method disclosed in conjunction with the embodiment of the present application can be directly embodied as a hardware processor for execution, or a combination of hardware and software modules in a processor for execution. The software module can be located in a storage medium mature in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in a memory, and the processor reads the information in the memory and completes the steps of the above method in conjunction with its hardware. To avoid repetition, it is not described in detail here.

[0070] It should be noted that the processor in the embodiment of the present application can be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method embodiment can be completed by an integrated logic circuit of hardware in the processor or an instruction in the form of software. The above processor can be a general-purpose processor, a digital signal processor DSP, an application-specific integrated circuit ASIC, a field programmable gate array FPGA or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in the embodiment of the present application can be directly embodied as a hardware decoding processor to perform, or the hardware and software modules in the decoding processor can be combined to perform. The software module can be located in a mature storage medium in the field such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in a memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware.

[0071] The on-orbit monitoring device and monitoring method for the cathode coupling state based on thrust fluctuation proposed in the present invention are introduced in detail above, and the principles and implementation methods of the present invention are explained. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A monitoring method for an on-orbit monitoring device of a cathode coupling state based on thrust fluctuations, characterized in that: The on-orbit monitoring device comprises a Faraday probe (1), a multispectral camera (2), a hollow cathode (3), a Hall thruster (4), an air supply unit (5), a thrust frame (6), a vacuum tank (7), a first power source (8) and a second power source (9); The Faraday probe (1) is used to measure the plume divergence angle and ion current of the Hall thruster (4); The multispectral camera (2) is located outside the vacuum tank (7) and is used to capture the plume image of the Hall thruster: The hollow cathode (3) generates ionized plasma by ionizing the working fluid gas; The Hall thruster (4) utilizes an electromagnetic field to accelerate ions and generate thrust; The gas supply unit (5) is used to transport working fluid gas to the Hall thruster (4) and the hollow cathode (3). The thrust frame (6) is responsible for supporting the Hall thruster (4) and measuring the thrust generated by it; The vacuum tank (7) provides a certain vacuum environment for the experiment; the Faraday probe (1), the hollow cathode (3), the Hall thruster (4) and the thrust frame (6) are all located inside the vacuum tank (7); The first power source (8) and the second power source (9) provide the required electrical energy to the hollow cathode (3) and the Hall thruster (4) respectively; The method specifically includes on-ground construction and on-orbit monitoring; On the ground, a thruster of a given design is used to monitor the plume using a Faraday probe (1) through the on-orbit monitoring device, and the coupling state of the Hall thruster (4) and the hollow cathode (3) is pre-calibrated in combination with the plume imaging method and the thrust frame: When in orbit, the plume of the Hall thruster (4) is photographed and uploaded to the terminal for comparison with the coupling state of the Hall thruster (4) and the hollow cathode (3) pre-calibrated in the database obtained on the ground, and the working condition of the Hall thruster (4) is adjusted until it matches the ground state, thereby completing the on-orbit monitoring.

2. The monitoring method according to claim 1, characterized in that: The on-site construction specifically includes the following steps: Step 1: Pump the vacuum tank (7) until the pressure drops to 10 -3 Below Pa; Step 2: starting the gas supply unit (5) to supply a certain flow rate of working gas to the hollow cathode (3) and the Hall thruster (4), and simultaneously starting the first power supply (8) and the second power supply (9) to supply a certain voltage to the hollow cathode (3) and the Hall thruster (4), thereby igniting the hollow cathode (3) and the Hall thruster (4); Step 3, when the plume is stable, the multispectral camera (2) is turned on to take a picture of the plume of the stably operating Hall thruster (4) and upload it to the database; Step 4, after the plume is stabilized, the plume divergence angle and ion current data measured by the Faraday probe (1) are transmitted to the database; Step 5: After the Hall thruster (4) is stabilized, the thrust frame (6) is used to measure the thrust of the Hall thruster (4) and the measurement result is uploaded to the database; Step six, calibrating the coupling state of the Hall thruster (4) and the hollow cathode (3) at this time as a standard; Step seven, repeating steps one to six, and pre-calibrating the coupling state of the Hall thruster (4) and the hollow cathode (3) under different working thrust conditions.

3. The monitoring method according to claim 2, characterized in that: In step one, before evacuating the vacuum tank (7), the thrust frame (6) is debugged; the mass of the required counterweight is estimated, and the number of counterweights to be installed within the mass range is selected.

4. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 3 are implemented.

5. A computer-readable storage medium for storing computer instructions, characterized in that: When the computer instructions are executed by a processor, the steps of the method according to any one of claims 1 to 3 are implemented.

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