Plasma propulsion dynamic torque measurement method, device and electronic equipment

Abstract

The application provides a kind of plasma propulsion dynamic torque measurement method, device and electronic equipment, it is related to plasma propulsion field, the method calibrates the calibration relationship of total fluorescent intensity and ion current density of thruster, measures the first time-varying data of fluorescent intensity distribution in the beam current of thruster changes with time and the second time-varying data of plasma luminous intensity of spatial point in the beam current changes with time;Adjust different laser wavelength and scan fluorescent signal under different laser wavelength, obtain the fluorescent intensity curve corresponding to laser wavelength by time axis alignment;According to the fluorescent intensity curve corresponding to laser wavelength, calculate the ion velocity distribution function of each spatial point at each time, calculate ion current density;Measure another vertical direction ion velocity distribution function and synthesis, obtain comprehensive average ion velocity, based on the comprehensive average ion velocity and ion current density corresponding to each spatial point Calculation dynamic torque density and based on dynamic torque density calculation dynamic torque.

Description

Technical Field

[0001] This application relates to the technical field of plasma propulsion, and in particular to a method, apparatus and electronic device for measuring dynamic torque in plasma propulsion. Background Technology

[0002] Currently, with the development of aerospace technology, the goal of long-term on-orbit operation of satellites has led to new demands for high specific impulse space propulsion systems. Plasma propulsion generates thrust by ionizing and accelerating plasma, offering the advantage of high specific impulse compared to chemical propulsion. However, plasma propulsion (such as Hall thruster and ion propulsion) generates torque in addition to thrust during operation.

[0003] This torque poses additional challenges to spacecraft control, especially for Hall and ion propulsion systems. Plasma exhibits microscopic circumferential instabilities, resulting in torque instabilities of tens of kHz or even higher, which can jeopardize spacecraft missions requiring attitude stability (such as drag-free control in gravitational wave detection). Therefore, accurate measurement of dynamic torque in plasma propulsion is crucial. However, current torque measurement methods in plasma propulsion have relatively low efficiency. Summary of the Invention

[0004] The purpose of this invention is to provide a method, apparatus, and electronic device for measuring dynamic torque in plasma propulsion, so as to solve the technical problem of low measurement efficiency in existing plasma propulsion torque measurement methods.

[0005] In a first aspect, this application provides a method for measuring the dynamic torque of plasma propulsion, wherein a thruster, a fiber optic collimator, a Faraday probe, and a corresponding translational slide are disposed within a vacuum chamber, the incident laser and the sheet laser element of the laser are already collimated, and the relative positions of the Faraday probe and the thruster are aligned; comprising:

[0006] In response to the operation of the thruster and the laser, the calibration relationship between the total fluorescence intensity and ion current density of the thruster is calibrated using the current measurement results of the Faraday probe. The laser wavelength of the laser is fixed and the first time-varying data of the fluorescence intensity distribution in the beam of the thruster changing with time and the second time-varying data of the plasma emission intensity of the spatial point in the beam changing with time are measured.

[0007] By adjusting different laser wavelengths and scanning fluorescence signals at different laser wavelengths, and aligning the time axis of the first time-varying data at different laser wavelengths based on the fluorescence signals using the second time-varying data, a fluorescence intensity curve corresponding to the laser wavelength at each spatial point at each moment is obtained.

[0008] The ion velocity distribution function at each spatial point at each moment is calculated based on the fluorescence intensity curve corresponding to the laser wavelength, and the ion current density is calculated based on the ion velocity distribution function using the calibration relationship and the integral value of the fluorescence intensity at the laser wavelength.

[0009] The ion velocity distribution function in another perpendicular direction is measured by changing the velocity measurement direction and then synthesized to obtain the comprehensive average ion velocity. The dynamic torque density is calculated based on the comprehensive average ion velocity and the ion current density corresponding to each spatial point. The dynamic torque of the thruster is obtained by spatial integration based on the dynamic torque density corresponding to all spatial points.

[0010] In one possible implementation, the calibration relationship between the total fluorescence intensity and ion current density of the thruster, calibrated using the current measurement results of the Faraday probe, in response to the operation of the thruster and the laser, includes:

[0011] In response to the operation of the thruster, the Faraday probe is controlled to move to the center of the plane to be measured of the thruster via the translation slide, the ion current density is measured through the probe source table corresponding to the Faraday probe, and the Faraday probe is moved outside the beam region of the thruster via the translation slide;

[0012] In response to the operation of the laser, fluorescence is collected by a high-speed camera, and during the collection process, the laser wavelength of the output laser is scanned by the laser to obtain fluorescence intensity distribution data at different laser wavelengths;

[0013] Based on the fluorescence intensity distribution data, the fluorescence intensity at the center of the thruster as a function of time is extracted. The fluorescence intensity as a function of time is combined with the laser wavelength as a function of time to obtain the fluorescence intensity as a function of laser wavelength.

[0014] Based on the fluorescence intensity variation curve with laser wavelength, the fluorescence intensity of all laser wavelengths is integrated to obtain the total fluorescence intensity.

[0015] Calculate the ratio coefficient between the total fluorescence intensity and the ion current density, calibrate the method of measuring ion density using fluorescence intensity based on the ratio coefficient, and determine the calibration relationship between the total fluorescence intensity and the ion current density of the thruster.

[0016] In one possible implementation, the first time-varying data of fixing the laser wavelength of the laser and measuring the fluorescence intensity distribution in the beam of the thruster over time, and the second time-varying data of the plasma emission intensity at spatial points in the beam over time, include:

[0017] The laser wavelength of the laser is fixed, and ions in the beam of the thruster are excited to generate fluorescence. A pulse delay trigger is used to simultaneously execute a first measurement task and a second measurement task, and the measurement durations of the first and second measurement tasks are kept consistent. The first measurement task is to use a high-speed camera to measure the first time-varying data of the fluorescence intensity distribution in the beam over time. The second measurement task is to use a photoelectric sensor to measure the second measurement data of the plasma emission intensity of a spatial point in the beam over time. The time axes of the first time-varying data and the second measurement data are synchronized.

[0018] In one possible implementation, adjusting different laser wavelengths and scanning fluorescence signals at different laser wavelengths, and aligning the time axes of the first time-varying data at different laser wavelengths based on the fluorescence signals using the second time-varying data to obtain the fluorescence intensity curve corresponding to the laser wavelength at each spatial point at each moment, includes:

[0019] By adjusting different laser wavelengths and conducting tests at multiple different laser wavelengths, fluorescence signals are obtained; wherein the time axes of the fluorescence signals at multiple laser wavelengths are asynchronous;

[0020] By moving the time axis using periodic reference light data at each laser wavelength, the reference signals of different laser wavelengths are aligned at the time positions of the peaks and troughs, so as to synchronize the fluorescence intensity change signals of different laser wavelengths over time on the time axis, and obtain the fluorescence intensity curve corresponding to the laser wavelength at each time point.

[0021] In one possible implementation, the step of calculating the ion velocity distribution function at each spatial point at each time moment based on the fluorescence intensity curve corresponding to the laser wavelength, and calculating the ion current density based on the ion velocity distribution function using the calibration relationship and the integral value of the fluorescence intensity at the laser wavelength, includes:

[0022] Based on the fluorescence intensity curve corresponding to the laser wavelength, the Doppler effect formula is used to calculate the ion velocity distribution function of each spatial point at each time.

[0023] The average ion velocity is calculated based on the ion velocity distribution function using the following formula:

[0024] ;

[0025] in, P For the ion velocity distribution function P - v The velocity distribution probability in the curve; The average ion velocity is represented by d; d denotes the differential symbol. v This refers to the ion velocity;

[0026] The fluorescence intensity is integrated over the laser wavelength in the fluorescence intensity curve corresponding to the laser wavelength to obtain the total fluorescence intensity integral result.

[0027] The ion current density is calculated based on the total fluorescence intensity integral and the calibration relationship.

[0028] In one possible implementation, the average ion velocity is the average ion velocity in the x-direction; the step of measuring the ion velocity distribution function in another perpendicular direction by changing the velocity measurement direction and synthesizing it to obtain the comprehensive average ion velocity includes:

[0029] The direction of velocity measurement is changed by rotating the test stand, and the average ion velocity in the y-direction is calculated using the formula.

[0030] The average ion velocity in the x-direction and the average ion velocity in the y-direction are combined to obtain the comprehensive average ion velocity.

[0031] In one possible implementation, calculating the dynamic torque density based on the combined average ion velocity and the ion current density corresponding to each of the spatial points includes:

[0032] For each instant, the torque generated per unit area at each spatial point is calculated using the following formula based on the combined average ion velocity and ion current density corresponding to that spatial point. T A :

[0033]

[0034] in, T A The dynamic torque density represents the torque generated by the spatial point per unit area; The ion current density; Mass of a single ion; L The lever arm that generates torque for the ion velocity at the spatial point is calculated based on the distance between the spatial point and the thruster axis and the direction of the ion velocity.

[0035] In one possible implementation, the step of spatially integrating the dynamic torque density corresponding to all the spatial points to obtain the dynamic torque of the thruster includes:

[0036] For each instant, the dynamic torque density corresponding to all the spatial points is integrated over the entire plane under test to obtain the curve of the total torque of the thruster changing with time, and the curve of the total torque changing with time is determined as the dynamic torque of the thruster.

[0037] Secondly, this application provides a plasma propulsion dynamic torque measurement device, in which a thruster, a fiber optic collimator, a Faraday probe, and a corresponding translational slide are disposed within a vacuum chamber, the incident laser and the sheet laser element of the laser are aligned, and the relative positions of the Faraday probe and the thruster are aligned; comprising:

[0038] The calibration module is used to calibrate the calibration relationship between the total fluorescence intensity and ion current density of the thruster in response to the operation of the thruster and the laser, using the current measurement results of the Faraday probe, fixing the laser wavelength of the laser and measuring the first time-varying data of the fluorescence intensity distribution in the beam of the thruster changing with time and the second time-varying data of the plasma emission intensity of the spatial point in the beam changing with time.

[0039] The alignment module is used to adjust different laser wavelengths and scan fluorescence signals under different laser wavelengths. Based on the fluorescence signals, the time axis of the first time-varying data under different laser wavelengths is aligned using the second time-varying data to obtain the fluorescence intensity curve corresponding to the laser wavelength at each spatial point at each moment.

[0040] The calculation module is used to calculate the ion velocity distribution function of each spatial point at each time according to the fluorescence intensity curve corresponding to the laser wavelength, and to calculate the ion current density based on the ion velocity distribution function using the calibration relationship and the integral value of the fluorescence intensity at the laser wavelength.

[0041] The integration module is used to measure the ion velocity distribution function in another perpendicular direction by changing the velocity measurement direction and synthesize it to obtain the comprehensive average ion velocity. Based on the comprehensive average ion velocity and the ion current density corresponding to each spatial point, the dynamic torque density is calculated. Based on the dynamic torque density corresponding to all spatial points, the dynamic torque of the thruster is obtained by spatial integration.

[0042] Thirdly, this application also provides an electronic device, including a memory and a processor, wherein the memory stores a computer program that can run on the processor, and the processor executes the computer program to implement the method described in the first aspect above.

[0043] Fourthly, this application also provides a computer-readable storage medium storing computer-executable instructions that, when invoked and executed by a processor, cause the processor to perform the method described in the first aspect above.

[0044] This application brings the following beneficial effects:

[0045] This application provides a plasma propulsion dynamic torque measurement method, device, and electronic device, which can respond to the operation of the thruster and the laser. It uses the current measurement results of the Faraday probe to calibrate the calibration relationship between the total fluorescence intensity and ion current density of the thruster; fixes the laser wavelength of the laser and measures the first time-varying data of the fluorescence intensity distribution in the beam of the thruster changing with time, and the second time-varying data of the plasma emission intensity at spatial points in the beam changing with time; adjusts different laser wavelengths and scans fluorescence signals at different laser wavelengths; aligns the time axes of the first time-varying data at different laser wavelengths based on the fluorescence signals and the second time-varying data to obtain the fluorescence intensity curve corresponding to the laser wavelength at each time point for each spatial point; calculates the ion velocity distribution function at each time point for each spatial point based on the fluorescence intensity curve corresponding to the laser wavelength; and calculates the ion current density based on the ion velocity distribution function using the calibration relationship and the integral value of the fluorescence intensity at the laser wavelength; measures the ion velocity distribution function in another perpendicular direction by changing the velocity measurement direction and synthesizes them to obtain the comprehensive average ion velocity, based on the ion velocity distribution function corresponding to each spatial point. The dynamic torque density is calculated based on the comprehensive average ion velocity and the ion current density. Spatial integration is then performed based on the dynamic torque density corresponding to all spatial points to obtain the dynamic torque of the thruster. In this scheme, by using a Faraday probe to calibrate the relationship between the laser-induced fluorescence signal and the ion current density, it is possible to eliminate the need for additional point-by-point measurements of ion density or ion current density during torque measurement. That is, by calibrating the laser-induced fluorescence method with a Faraday probe before the formal torque measurement, it is not necessary to measure the ion current density at every point on the plane under each measurement condition using a Faraday probe, thus saving measurement time. Furthermore, by using a laser to extend the laser and measuring the circumferential ion velocity through planar laser-induced fluorescence, it is possible to acquire ion velocity information at multiple points in space at once. That is, by using the planar laser-induced fluorescence method to measure the circumferential ion velocity, the ion velocity at all points in space can be measured simultaneously without point-by-point measurement. High-speed cameras typically have high resolution at high frame rates, thus reducing the measurement process from thousands or tens of thousands of measurements to a single measurement, greatly improving the measurement speed and solving the technical problem of low measurement efficiency in existing plasma propulsion torque measurement methods.

[0046] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0048] Figure 1 A schematic flowchart illustrating the plasma propulsion dynamic torque measurement method provided in this application embodiment;

[0049] Figure 2 Another schematic diagram of the plasma propulsion dynamic torque measurement method provided in the embodiments of this application;

[0050] Figure 3 This is a schematic diagram of the structure of the plasma propulsion dynamic torque measurement system provided in the embodiments of this application;

[0051] Figure 4(a) is a partial schematic diagram of the data processing process corresponding to the plasma propulsion dynamic torque measurement method provided in the embodiment of this application;

[0052] Figure 4(b) is another schematic diagram of the data processing process corresponding to the plasma propulsion dynamic torque measurement method provided in the embodiments of this application;

[0053] Figure 4(c) is another schematic diagram of the data processing process corresponding to the plasma propulsion dynamic torque measurement method provided in the embodiment of this application;

[0054] Figure 4(d) is another schematic diagram of the data processing process corresponding to the plasma propulsion dynamic torque measurement method provided in the embodiments of this application;

[0055] Figure 4(e) is another schematic diagram of the data processing process corresponding to the plasma propulsion dynamic torque measurement method provided in the embodiments of this application;

[0056] Figure 4(f) is another schematic diagram of the data processing process corresponding to the plasma propulsion dynamic torque measurement method provided in the embodiments of this application;

[0057] Figure 4(g) is another schematic diagram of the data processing process corresponding to the plasma propulsion dynamic torque measurement method provided in the embodiments of this application;

[0058] Figure 5 A schematic diagram of the structure of a plasma propulsion dynamic torque measuring device provided in an embodiment of this application;

[0059] Figure 6 A schematic diagram of the structure of an electronic device provided in an embodiment of this application is shown. Detailed Implementation

[0060] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0061] The terms "comprising" and "having," and any variations thereof, used in the embodiments of this application, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the steps or units listed, but may optionally include other steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices.

[0062] Currently, torque measurement in the field of plasma propulsion mainly includes two methods: (1) Direct measurement using a torsion pendulum thruster, where the pendulum is connected to the platform via an elastic pivot, and the angle of rotation of the pendulum is directly proportional to the torque. (2) Indirect method: The ion velocity at different points in space is measured using a laser-induced fluorescence scheme, the ion current density is measured using a Faraday probe, and finally the torque is calculated by integration. The principle of the laser-induced fluorescence scheme is as follows: a specific laser hitting a specific particle will produce fluorescence, and the fluorescence intensity is proportional to the local particle density. By using a narrow-linewidth laser to scan the wavelength in a small range, the proportion of different velocity groups in a specific particle at a certain location can be measured based on the Doppler effect. The velocity distribution function is obtained, and the average velocity of a specific particle in the local area can be calculated based on the velocity distribution function. The principle of the Faraday probe is that it is an electrode that receives ions and forms a current in the circuit. The magnitude of the current is measured, and the local ion current density can be obtained by combining the probe area.

[0063] The problem with the above method (1) which uses a torsion pendulum thrust frame for direct measurement is that the torsion pendulum is limited by its structure and its natural frequency is in the range of several Hz, making it impossible to measure high-frequency dynamic torque signals of tens of kHz. The core problems of the above method (2), which measures the ion current density and ion velocity distribution function at various points in space using probes and optical means (laser-induced fluorescence) and then calculates the torque, mainly include three points: (a) Current optical measurement methods only measure the ion velocity at a single point. However, due to the non-uniformity in the structure and magnetic field processing of electric propulsion, axial ion velocity non-uniformity is inevitable. Therefore, it is necessary to scan the circumferential ion velocity of the thruster beam field point by point, which consumes a lot of time and is cumbersome; (b) Since the velocity distribution function at each point needs to be measured by scanning the laser wavelength to measure the relative proportion of the number of ions with different velocity distributions at that point, and the scanning frequency of the laser is only a few Hz to tens of Hz, the time resolution for measuring the ion velocity distribution function and calculating the torque is also at most tens of Hz, which cannot realize the measurement of high-frequency dynamic torque in actual electric propulsion; (c) Since the data of laser-induced fluorescence cannot reflect the absolute density of ions, it is necessary to scan the ion current density at each spatial point using a Faraday probe, which also leads to an extremely long torque measurement time for a thruster operating condition. Therefore, the measurement efficiency of the torque measurement method in the current plasma propulsion field is low.

[0064] Based on this, the embodiments of this application provide a method, apparatus and electronic device for measuring dynamic torque of plasma propulsion, which can solve the technical problem of low measurement efficiency of plasma propulsion torque measurement method.

[0065] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0066] Figure 1 This is a schematic flowchart illustrating a plasma propulsion dynamic torque measurement method provided in an embodiment of this application. The thruster, fiber optic collimator, Faraday probe, and corresponding translational slide are housed within a vacuum chamber. The incident laser and sheet laser element of the laser have been aligned, and the relative positions of the Faraday probe and the thruster are aligned. Figure 1 As shown, the method includes:

[0067] In step S110, in response to the operation of the thruster and the laser, the calibration relationship between the total fluorescence intensity and ion current density of the thruster is calibrated using the current measurement results of the Faraday probe. The laser wavelength of the laser is fixed and the first time-varying data of the fluorescence intensity distribution in the beam of the thruster changing with time and the second time-varying data of the plasma emission intensity at the spatial point in the beam changing with time are measured.

[0068] For example, such as Figure 2As shown, firstly, the thruster, fiber collimator, Faraday probe, and its slide are installed in the vacuum chamber to calibrate the incident laser and the sheet light components; the relative positions of the Faraday probe and the thruster are aligned. In step S110 above, after the thruster operates and the laser is turned on, the relationship between the total fluorescence intensity and ion current density is calibrated using the Faraday probe results. Subsequently, the laser wavelength of the incident laser is fixed, and the change in fluorescence intensity distribution over time is recorded using a high-speed camera. Simultaneously, the change in plasma emission intensity at a certain point in the thruster beam over time is measured using a photoelectric sensor. The two measurements are started simultaneously using a pulse delay trigger, and the total measurement duration is kept the same. The high-speed camera can be replaced with a photoelectric probe array with high time resolution, as long as it can achieve high-speed acquisition of planar fluorescence signals. The Faraday probe used in this scheme can be a Langmuir probe or emission spectroscopy method, mainly used to measure ion density or ion current density. Any method that can accurately measure these two parameters can replace the Faraday probe and complete the calibration of the laser-induced fluorescence signal.

[0069] The structure of the test system is as follows Figure 3 As shown, the thruster and its working system consist of thruster 1, rotatable platform 2, vacuum chamber 3, and power supply 4; the laser-induced fluorescence system consists of narrow-linewidth continuously tunable semiconductor laser 5, beam splitter 6, energy meter 7, beam splitter 8, wavelength meter 9, reflector 10, cylindrical mirror 11, glass flange 12, glass flange 13, fluorescence wavelength filter 14, and high-speed camera 15; the Faraday probe system consists of two-dimensional translational slide 16, Faraday probe 17, and probe source table 18; the reference light collection system consists of fiber collimator 19, photodetector 20, and oscilloscope 21; and the control and data collection system consists of pulse delay trigger 22 and computer 23.

[0070] Specifically, in operation, the thruster 1, rotatable platform 2, Faraday probe 17, and its translation slide 16 are first installed in designated positions within the vacuum chamber 3. The axis of the thruster is defined as the z-direction, and the translation direction of the translation slide 16 is perpendicular to the axis of the thruster 1. The thruster is connected to the power supply 4 via a through-chamber cable. The fiber optic probe is installed diagonally in front of the thruster, maintaining a certain distance from the axis of the thruster 1 to prevent it from being eroded by the plume of the thruster 1. It is connected to the photoelectric probe 20 outside the chamber via a through-chamber fiber optic cable. In the external arrangement, a narrow-linewidth continuously tunable semiconductor laser outputs laser light capable of exciting ion wavelengths. The laser portion is introduced into the energy meter 7 and wavelength meter 9 via beam splitters 6 and 8, respectively, to monitor the wavelength and energy of the laser and ensure the stability of the laser output. The laser beam then passes through mirror 10 and is incident on cylindrical mirror 11. Through cylindrical mirror 11, the original line beam is expanded into a surface beam on a plane parallel to the XY plane. This surface beam is then incident on the plasma through glass flange 12, with the incident direction being the negative x-direction. This plane is the test plane used to measure the ion velocity distribution and ion current density in the experiment. A specific laser beam causes specific ions on the test plane to fluoresce. Fine-tuning the laser wavelength allows different ion groups at different velocities to fluoresce. The intensity of this fluorescence reflects the ion distribution at that velocity. The fluorescence field of the test plane is measured by high-speed camera 15 through high-transmittance glass flange 13 and a narrow-band filter 14 for the fluorescence wavelength. Faraday probe 17 is fixed on translational slide 16 and connected to probe source meter 18 via a through-cell cable. Source meter 18 outputs a negative bias voltage to shield Faraday probe 17 from ions and measures the current flowing through Faraday probe 17, calculating the current density at Faraday probe 17. (θ). The photodetector 20 is connected to the fiber optic collimator 19 in the cabin via an optical fiber, which can convert the light intensity at a point on the plane under test into a voltage signal. The output voltage signal is connected to the oscilloscope 21 via a cable, and the signal can be acquired and read in real time by the oscilloscope. The pulse delay trigger 22 can output a control signal to enable the oscilloscope and the high-speed camera to acquire data synchronously. After the data acquisition is completed, it is summarized to the computer 23 for post-processing and analysis.

[0071] After installing the internal and external devices, calibrate the optical path and probes. Adjust the position and angle of the reflector 10 and cylindrical mirror 11 so that the laser incident direction is completely perpendicular to the axis of the thruster 1, and the expanded beam width is greater than the diameter of the thruster beam. Adjust the angle of the Faraday probe 17 and the translation slide 16 so that the direction of the Faraday probe 17 is the same as the thruster axis, i.e., the x-direction. The two slide rails of the two-dimensional translation slide 16 are respectively aligned with and perpendicular to the axis of the thruster 1, i.e., the x and z directions.

[0072] Subsequently, calibration of the Faraday probe 17 and the laser-induced fluorescence signal was carried out. As one possible implementation, in response to the operation of the thruster and laser, the calibration relationship between the total fluorescence intensity and ion current density of the thruster is determined using the current measurement results of the Faraday probe. Specifically, this may include the following steps:

[0073] In response to the operation of the thruster, the Faraday probe is controlled to move to the center of the plane to be measured of the thruster via a translation slide. The ion current density is measured through the probe source table corresponding to the Faraday probe, and the Faraday probe is moved to outside the beam region of the thruster via the translation slide.

[0074] In response to the operation of the laser, fluorescence is collected by a high-speed camera, and during the collection process, the laser wavelength of the output laser is scanned by the laser to obtain fluorescence intensity distribution data at different laser wavelengths;

[0075] Based on the fluorescence intensity distribution data, the fluorescence intensity at the center of the thruster is extracted as a function of time. The fluorescence intensity as a function of time is combined with the laser wavelength as a function of time to obtain the fluorescence intensity as a function of laser wavelength.

[0076] Based on the fluorescence intensity variation curve with laser wavelength, the fluorescence intensity of all laser wavelengths is integrated to obtain the total fluorescence intensity; the proportionality coefficient between the total fluorescence intensity and ion current density is calculated, and the method of measuring ion density using fluorescence intensity is calibrated according to the proportionality coefficient to determine the calibration relationship between the total fluorescence intensity and ion current density of the thruster.

[0077] For the specific calibration process of the Faraday probe and laser-induced fluorescence signal, for example, vacuum chamber 3 is evacuated to reduce the internal air pressure to below 10. -3 Pa satisfies the operating conditions of thruster 1. The thruster operates, moving the Faraday probe 17 to the center of the thruster's test plane via the two-dimensional translation slide 16, and measuring the ion current density at that location using the probe source meter 18. (Steady-state time average). Then, the Faraday probe 17 is moved outside the beam region of thruster 1 using a two-dimensional translation slide 16 to prevent interference with subsequent measurements. Laser 5 is turned on, and fluorescence is collected via high-speed camera 15. During collection, laser 5 is operated to scan the wavelength of the output laser, ultimately obtaining the fluorescence intensity distribution at different wavelengths. The fluorescence intensity variation curve at the thruster axis center is extracted, and combined with the laser wavelength variation curve over time, the fluorescence intensity variation curve over wavelength is obtained. The total intensity S is obtained by integrating the fluorescence intensities across all wavelengths. total (Units are wavelength units multiplied by light intensity units). Calculate the total fluorescence intensity S. total and ion current density The proportionality coefficient 'a' is used to complete the calibration of the method for measuring ion density using fluorescence intensity.

[0078] Subsequently, time-domain measurements of the fixed laser wavelength are performed. As an example, this measurement process, which involves fixing the laser wavelength and measuring the first time-varying data of the fluorescence intensity distribution in the thruster's beam over time, as well as the second time-varying data of the plasma emission intensity at spatial points in the beam over time, may specifically include the following steps:

[0079] A fixed laser wavelength is used to excite ions in the beam of the thruster to generate fluorescence. A pulse delay trigger simultaneously executes a first measurement task and a second measurement task, keeping the measurement durations of the first and second measurement tasks consistent. The first measurement task is to use a high-speed camera to measure the first time-varying data of the fluorescence intensity distribution in the beam over time. The second measurement task is to use a photoelectric sensor to measure the second measurement data of the plasma emission intensity at a spatial point in the beam over time. The time axes of the first time-varying data and the second measurement data are synchronized.

[0080] For example, suppose the wavelength of the laser that excites 0-velocity ions is... λ 0, fix the laser wavelength at 5. λ A certain wavelength near 0 λ 1, which triggers a speed of v Ions of 1. The oscilloscope 21 and high-speed camera 15 are simultaneously activated by the pulse delay trigger 22 to acquire data, obtaining the fluorescence intensity and plasma emission intensity curves at each time point and the reference point. The time axes of both are synchronized, as shown in the top of Figure 4(a). Subsequently, the laser wavelength is changed to a value of 1. λ 1. λ 2. λ Measurements were conducted at multiple wavelengths, and the results are shown in Figure 4(a). However, the signal time axis is not synchronized at each wavelength.

[0081] Step S120: Adjust different laser wavelengths and scan fluorescence signals under different laser wavelengths. Based on the fluorescence signals, align the time axis of the first time-varying data under different laser wavelengths using the second time-varying data to obtain the fluorescence intensity curve corresponding to the laser wavelength at each spatial point at each moment.

[0082] In this step, different laser wavelengths are scanned, and the time axis of the fluorescence intensity distribution video under different laser wavelengths is aligned with the light intensity curve of the photoelectric sensor to obtain the fluorescence intensity-wavelength curve of each spatial point at each moment.

[0083] In one optional implementation, the process of adjusting different laser wavelengths and scanning fluorescence signals at different laser wavelengths, and aligning the time axes of the first time-varying data at different laser wavelengths based on the fluorescence signals using second time-varying data, yields a fluorescence intensity curve corresponding to the laser wavelength at each spatial point at each moment. Specifically, this may include the following steps:

[0084] Different laser wavelengths were adjusted and tested at multiple different laser wavelengths to obtain fluorescence signals. However, the time axes of the fluorescence signals at multiple laser wavelengths were not synchronized. By moving the time axis with periodic reference light data at each laser wavelength, the reference signals of different laser wavelengths were aligned at the time positions of the peaks and troughs. This synchronized the fluorescence intensity changes over time at different laser wavelengths on the time axis, resulting in the fluorescence intensity curve corresponding to the laser wavelength at each spatial point at each moment.

[0085] For example, in the process of aligning the time axis of test results of different laser wavelengths, the time axis is moved by periodic reference light data under each wavelength so that the reference signals of different wavelengths are aligned at the time positions of the peaks and troughs. This allows the fluorescence intensity of different wavelengths to be synchronized with time on the time axis. The result after aligning the time axis is shown in Figure 4(b).

[0086] Step S130: Calculate the ion velocity distribution function of each spatial point at each time step based on the fluorescence intensity curve corresponding to the laser wavelength, and calculate the ion current density based on the ion velocity distribution function using the calibration relationship and the integral value of the fluorescence intensity at the laser wavelength.

[0087] In this step, the ion velocity distribution function at a given point and time is obtained through the Doppler effect. That is, the laser wavelength is correlated with the measured ion velocity using the Doppler effect formula to obtain the variation law of the ion velocity distribution function at each point over time, and the average ion velocity in that direction at that point and time is obtained. The ion current density at that point and time is obtained by integrating the fluorescence intensity over the wavelength and using the aforementioned calibration results.

[0088] In one possible implementation, the above-mentioned calculation of the ion velocity distribution function at each spatial point at each time step based on the fluorescence intensity curve corresponding to the laser wavelength, and the calculation of the ion current density based on the ion velocity distribution function using the calibration relationship and the integral value of the fluorescence intensity over the laser wavelength, may specifically include the following steps:

[0089] Based on the fluorescence intensity curve corresponding to the laser wavelength, the ion velocity distribution function at each spatial point at each time moment is calculated using the Doppler effect; the average ion velocity is then calculated using the following formula based on the ion velocity distribution function:

[0090] ;in,P For the ion velocity distribution function P - v The velocity distribution probability in the curve; The average ion velocity is represented by d; d denotes the differential symbol. v This refers to the ion velocity;

[0091] The fluorescence intensity is integrated along the laser wavelength in the fluorescence intensity curve corresponding to the laser wavelength to obtain the total fluorescence intensity integral result; the ion current density is calculated based on the total fluorescence intensity integral result and the calibration relationship.

[0092] For the calculation of ion velocity distribution function and ion current density at each point, for example, taking one point in the plane to be measured as an example, the aforementioned steps obtained the variation law of fluorescence signal with time at different wavelengths, and the fluorescence intensity signals at different laser wavelengths have been synchronized in time, as shown in Figure 4(c). For a certain point on the time axis... t 1. It can extract different wavelengths. λ Fluorescence intensity I lif , obtain I lif - λ Curve. Through I lif - λ It is possible to calculate: (1) Ion velocity distribution function and average velocity: Since each wavelength can only excite the analyte ion at a certain (ion) velocity, it is possible to calculate: I lif - λ The curve is transformed into an ion velocity distribution function, which is... P - v curve, in which P The probability distribution is shown in Figure 4(d). The average ion velocity is obtained using the above formula. (2) Ion current density: in I lif - λ In the curve, for I lif exist λ Integrating, the result is S total1 Based on the calibration results from the preceding steps, the ion current density is calculated as follows: 1=a S total1 Through the above steps, the time was calculated. t 1. Average ion velocity in the x-direction at this point And ion current density (regardless of direction). The average ion velocity in the x-direction can then be calculated. The curves showing the change of ion current density (without distinguishing direction) over time.

[0093] Step S140: The ion velocity distribution function in another perpendicular direction is measured by changing the velocity measurement direction and synthesized to obtain the comprehensive average ion velocity. The dynamic torque density is calculated based on the comprehensive average ion velocity and ion current density corresponding to each spatial point. The dynamic torque of the thruster is obtained by spatial integration based on the dynamic torque density corresponding to all spatial points.

[0094] In this step, the thruster is rotated, and the ion velocity distribution function and average velocity in the opposite perpendicular direction at each point at each time moment are measured using the same method as described above. The average ion velocity vector and ion current density at each point at each time moment are obtained using the above method, and the dynamic torque density at each point is measured. The torques of all points are superimposed at each time moment to calculate the high-resolution dynamic torque of the thruster.

[0095] As one possible implementation, the aforementioned average ion velocity is the average ion velocity in the x-direction; by changing the velocity measurement direction to measure the ion velocity distribution function in another perpendicular direction and synthesizing them, a comprehensive average ion velocity is obtained, which may specifically include the following steps:

[0096] The velocity measurement direction is changed by rotating the test stand, and the average ion velocity in the y-direction is calculated using a formula. The average ion velocity in the x-direction and the average ion velocity in the y-direction are then combined to obtain the comprehensive average ion velocity.

[0097] For example, when changing the velocity measurement direction, the rotating platform 2 is rotated 90 degrees, and the average ion velocity in the y-direction is measured using the same method described above. The average ion velocity at that point is the sum of the velocities in the x and y directions. Therefore, the average ion velocity at each point can be obtained. The curve showing the change over time is shown in Figure 4(e).

[0098] In one possible implementation, the calculation of dynamic torque density based on the comprehensive average ion velocity and ion current density corresponding to each spatial point may specifically include the following steps: for each moment, calculate the torque generated per unit area at the spatial point using the following formula based on the comprehensive average ion velocity and ion current density corresponding to each spatial point. T A :

[0099]

[0100] in, T A Dynamic torque density represents the torque generated per unit area at a spatial point; This represents the ion current density. Mass of a single ion; L The lever arm that generates torque for the ion velocity at the space point is calculated based on the distance between the space point and the thruster axis and the direction of the ion velocity.

[0101] For torque calculation, at each point on the plane under test, at each moment, based on the ion current density... and average ion velocity The torque generated per unit area at that point at that moment can be calculated using the formula above. T A ,in T A The unit is N / m. The unit is A / m 2 , m i The unit is kg; the calculation results are shown in Figure 4(f).

[0102] As an optional implementation, the above-mentioned spatial integration based on the dynamic torque density corresponding to all spatial points to obtain the dynamic torque of the thruster may specifically include the following steps: for each moment, integrate the entire plane under test according to the dynamic torque density corresponding to all spatial points to obtain the curve of the total torque of the thruster changing with time, and determine the curve of the total torque changing with time as the dynamic torque of the thruster.

[0103] For example, by integrating the torque per unit area at each point over the entire plane under test, the total torque of thruster 1 at that moment can be obtained. T By calculating in this way for each moment, the curve of torque changing with time can be obtained, which is the dynamic torque, as shown in Figure 4(g).

[0104] In this embodiment, by using a Faraday probe to calibrate the relationship between laser-induced fluorescence signal and ion current density, it is possible to eliminate the need for additional point-by-point measurements of ion density or ion current density during torque measurement. Specifically, by calibrating the laser-induced fluorescence method with a Faraday probe before the formal torque measurement, it is not necessary to measure the ion current density at every point on the plane under each measurement condition, thus saving measurement time. Furthermore, by using a laser to extend the laser beam and measuring the circumferential ion velocity through planar laser-induced fluorescence, it is possible to acquire ion velocity information at multiple points in space in a single measurement. That is, by using the planar laser-induced fluorescence method to measure the circumferential ion velocity, the ion velocity at all points in space can be measured simultaneously, eliminating the need for point-by-point measurements. High-speed cameras typically have high resolution at high frame rates, thus reducing the measurement process from thousands or tens of thousands of measurements to a single measurement, significantly improving the measurement speed and solving the technical problem of low measurement efficiency in existing plasma propulsion torque measurement methods.

[0105] Existing direct thrust measurement methods are limited by the natural frequency of the torsional yaw, making it impossible to measure high-frequency torque signals. However, in this embodiment, compared to direct thrust measurement, high-frequency dynamic torque of tens of kHz can be obtained through time-resolved measurement of ion velocity.

[0106] Furthermore, compared to the indirect measurement methods in existing technologies, this application embodiment uses plasma luminescence information for time axis synchronization, achieving time axis synchronization of fluorescence time-domain signals under different laser wavelengths, and obtaining a time-resolved circumferential ion velocity distribution function. Specifically, by using the luminescence intensity at a certain point on the plane under test, the time axis synchronization of fluorescence intensity time-domain information under different wavelengths is achieved, realizing high-frequency measurement of ion velocity distribution functions at multiple points in space. This solves the problem that conventional methods cannot perform time-resolved measurements due to the need for wavelength scanning in laser-induced fluorescence, allowing this method to be used for dynamic torque measurement.

[0107] Figure 5 A schematic diagram of a plasma propulsion dynamic torque measurement device is provided. The thruster, fiber optic collimator, Faraday probe, and corresponding translational slide are arranged inside a vacuum chamber. The incident laser and sheet laser element of the laser have been aligned, and the relative positions of the Faraday probe and the thruster are aligned. Figure 5 As shown, the plasma propulsion dynamic torque measurement device 500 includes:

[0108] The calibration module 501 is used to calibrate the calibration relationship between the total fluorescence intensity and ion current density of the thruster in response to the operation of the thruster and the laser, using the current measurement results of the Faraday probe, fixing the laser wavelength of the laser and measuring the first time-varying data of the fluorescence intensity distribution in the beam of the thruster changing with time and the second time-varying data of the plasma emission intensity of the spatial point in the beam changing with time.

[0109] Alignment module 502 is used to adjust different laser wavelengths and scan fluorescence signals under different laser wavelengths. Based on the fluorescence signals, the time axis of the first time-varying data under different laser wavelengths is aligned with the second time-varying data to obtain the fluorescence intensity curve corresponding to the laser wavelength at each spatial point at each moment.

[0110] The calculation module 503 is used to calculate the ion velocity distribution function of each spatial point at each time according to the fluorescence intensity curve corresponding to the laser wavelength, and to calculate the ion current density based on the ion velocity distribution function using the calibration relationship and the integral value of the fluorescence intensity at the laser wavelength.

[0111] The integration module 504 is used to measure the ion velocity distribution function in another perpendicular direction by changing the velocity measurement direction and synthesize it to obtain the comprehensive average ion velocity. Based on the comprehensive average ion velocity and the ion current density corresponding to each spatial point, the dynamic torque density is calculated. Based on the dynamic torque density corresponding to all spatial points, the dynamic torque of the thruster is obtained by spatial integration.

[0112] The plasma propulsion dynamic torque measurement device provided in this application embodiment has the same technical features as the plasma propulsion dynamic torque measurement method provided in the above embodiments, so it can also solve the same technical problems and achieve the same technical effects.

[0113] An electronic device provided in this application embodiment, such as Figure 6 As shown, the electronic device 600 includes a processor 602 and a memory 601. The memory stores a computer program that can run on the processor. When the processor executes the computer program, it implements the steps of the method provided in the above embodiments.

[0114] See Figure 6 The electronic device also includes a bus 603 and a communication interface 604. The processor 602, the communication interface 604 and the memory 601 are connected through the bus 603. The processor 602 is used to execute executable modules, such as computer programs, stored in the memory 601.

[0115] The memory 601 may include high-speed random access memory (RAM) or non-volatile memory, such as at least one disk storage device. Communication between this system network element and at least one other network element is achieved through at least one communication interface 604 (which can be wired or wireless), such as the Internet, wide area network, local area network, or metropolitan area network.

[0116] Bus 603 can be an ISA bus, PCI bus, or EISA bus, etc. The bus can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 6 The symbol is represented by a single double-headed arrow, but this does not mean that there is only one bus or one type of bus.

[0117] The memory 601 is used to store programs. After receiving an execution instruction, the processor 602 executes the program. The method executed by the apparatus defined by the process disclosed in any of the preceding embodiments of this application can be applied to the processor 602 or implemented by the processor 602.

[0118] The processor 602 may be an integrated circuit chip with signal processing capabilities. In implementation, each step of the above method can be completed by the integrated logic circuitry in the hardware of the processor 602 or by instructions in software form. The processor 602 may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this application can be directly manifested as execution by a hardware decoding processor, or execution by a combination of hardware and software modules in the decoding processor. The software module can reside in a mature storage medium in the field, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or registers. This storage medium is located in memory 601, and processor 602 reads the information from memory 601 and, in conjunction with its hardware, completes the steps of the above method.

[0119] Corresponding to the above-described plasma propulsion dynamic torque measurement method, this application embodiment also provides a computer-readable storage medium storing computer-executable instructions. When the computer-executable instructions are invoked and executed by a processor, the computer-executable instructions cause the processor to perform the steps of the above-described plasma propulsion dynamic torque measurement method.

[0120] The plasma propulsion dynamic torque measuring device provided in this application embodiment can be specific hardware on the device or software or firmware installed on the device. The device provided in this application embodiment has the same implementation principle and technical effects as the aforementioned method embodiment. For the sake of brevity, any parts not mentioned in the device embodiment can be referred to the corresponding content in the aforementioned method embodiment. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can all be referred to the corresponding processes in the above method embodiments, and will not be repeated here.

[0121] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the displayed or discussed mutual couplings, direct couplings, or communication connections may be through some communication interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms.

[0122] For example, the flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram and / or flowchart, and combinations of blocks in block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0123] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0124] In addition, the functional units in the embodiments provided in this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0125] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the plasma propulsion dynamic torque measurement method described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0126] 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. In addition, the terms "first", "second", "third", etc. are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0127] Finally, it should be noted that the above-described embodiments are merely specific implementations of this application, used to illustrate the technical solutions of this application, and not to limit them. The protection scope of this application is not limited thereto. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the scope of the technology disclosed in this application; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application. All should be covered within the protection scope of this application. Therefore, the protection scope of this application should be determined by the protection scope of the claims.

Claims

1. A method for measuring dynamic torque in plasma propulsion, characterized in that, The thruster, fiber optic collimator, Faraday probe, and corresponding translation slide are housed within a vacuum chamber. The incident laser and sheet laser elements of the laser have been aligned, and the relative positions of the Faraday probe and the thruster are aligned. The system includes: In response to the operation of the thruster and the laser, the calibration relationship between the total fluorescence intensity and ion current density of the thruster is calibrated using the current measurement results of the Faraday probe. The laser wavelength of the laser is fixed and the first time-varying data of the fluorescence intensity distribution in the beam of the thruster changing with time and the second time-varying data of the plasma emission intensity of the spatial point in the beam changing with time are measured. By adjusting different laser wavelengths and scanning fluorescence signals at different laser wavelengths, and aligning the time axis of the first time-varying data at different laser wavelengths with the second time-varying data based on the fluorescence signals, a fluorescence intensity curve corresponding to the laser wavelength at each spatial point at each moment is obtained. The ion velocity distribution function at each spatial point at each moment is calculated based on the fluorescence intensity curve corresponding to the laser wavelength, and the ion current density is calculated based on the ion velocity distribution function using the calibration relationship and the integral value of the fluorescence intensity at the laser wavelength. The ion velocity distribution function in another perpendicular direction is measured by changing the velocity measurement direction and then synthesized to obtain the comprehensive average ion velocity. The dynamic torque density is calculated based on the comprehensive average ion velocity and the ion current density corresponding to each spatial point. The dynamic torque of the thruster is obtained by spatial integration based on the dynamic torque density corresponding to all spatial points.

2. The method according to claim 1, characterized in that, The calibration relationship between the total fluorescence intensity and ion current density of the thruster, in response to the operation of the thruster and the laser, and using the current measurement results of the Faraday probe, includes: In response to the operation of the thruster, the Faraday probe is controlled to move to the center of the plane to be measured of the thruster via the translation slide, the ion current density is measured through the probe source table corresponding to the Faraday probe, and the Faraday probe is moved to outside the beam region of the thruster via the translation slide; In response to the operation of the laser, fluorescence is collected by a high-speed camera, and during the collection process, the laser wavelength of the output laser is scanned by the laser to obtain fluorescence intensity distribution data at different laser wavelengths; Based on the fluorescence intensity distribution data, the fluorescence intensity at the center of the thruster as a function of time is extracted. The fluorescence intensity as a function of time is combined with the laser wavelength as a function of time to obtain the fluorescence intensity as a function of laser wavelength. Based on the fluorescence intensity variation curve with laser wavelength, the fluorescence intensity of all laser wavelengths is integrated to obtain the total fluorescence intensity. Calculate the proportionality coefficient between the total fluorescence intensity and the ion current density, calibrate the method of measuring ion density using fluorescence intensity based on the proportionality coefficient, and determine the calibration relationship between the total fluorescence intensity and the ion current density of the thruster.

3. The method according to claim 1, characterized in that, The first time-varying data on fixing the laser wavelength of the laser and measuring the fluorescence intensity distribution in the beam of the thruster over time, and the second time-varying data on the plasma emission intensity at spatial points in the beam over time, include: The laser wavelength of the laser is fixed, and ions in the beam of the thruster are excited to generate fluorescence. A pulse delay trigger is used to simultaneously execute a first measurement task and a second measurement task, and the measurement durations of the first and second measurement tasks are kept consistent. The first measurement task is to use a high-speed camera to measure the first time-varying data of the fluorescence intensity distribution in the beam over time. The second measurement task is to use a photoelectric sensor to measure the second time-varying data of the plasma emission intensity of a spatial point in the beam over time. The time axes of the first time-varying data and the second time-varying data are synchronized.

4. The method according to claim 1, characterized in that, The process of adjusting different laser wavelengths and scanning fluorescence signals at different laser wavelengths, aligning the time axis of the first time-varying data at different laser wavelengths based on the fluorescence signals using the second time-varying data, and obtaining the fluorescence intensity curve corresponding to the laser wavelength at each spatial point at each moment includes: By adjusting different laser wavelengths and conducting tests at multiple different laser wavelengths, fluorescence signals are obtained; wherein the time axes of the fluorescence signals at multiple laser wavelengths are asynchronous; By moving the time axis using periodic reference light data at each laser wavelength, the reference signals of different laser wavelengths are aligned at the time positions of the peaks and troughs, so as to synchronize the fluorescence intensity change signals of different laser wavelengths over time on the time axis, and obtain the fluorescence intensity curve corresponding to the laser wavelength at each time point.

5. The method according to claim 1, characterized in that, The step of calculating the ion velocity distribution function at each spatial point at each time moment based on the fluorescence intensity curve corresponding to the laser wavelength, and calculating the ion current density based on the ion velocity distribution function using the calibration relationship and the integral value of the fluorescence intensity at the laser wavelength, includes: Based on the fluorescence intensity curve corresponding to the laser wavelength, the Doppler effect formula is used to calculate the ion velocity distribution function of each spatial point at each time. The average ion velocity is calculated based on the ion velocity distribution function using the following formula: ； in, P For the ion velocity distribution function P - v The velocity distribution probability in the curve; The average ion velocity is represented by d; d denotes the differential symbol. v This refers to the ion velocity. The fluorescence intensity is integrated over the laser wavelength in the fluorescence intensity curve corresponding to the laser wavelength to obtain the total fluorescence intensity integral result. The ion current density is calculated based on the total fluorescence intensity integral and the calibration relationship.

6. The method according to claim 5, characterized in that, The average ion velocity is the average ion velocity in the x-direction; The process of measuring the ion velocity distribution function in another perpendicular direction by changing the velocity measurement direction and synthesizing the results to obtain a comprehensive average ion velocity includes: The direction of velocity measurement is changed by rotating the test stand, and the average ion velocity in the y-direction is calculated using the formula. The average ion velocity in the x-direction and the average ion velocity in the y-direction are combined to obtain the comprehensive average ion velocity.

7. The method according to claim 6, characterized in that, The calculation of dynamic torque density based on the comprehensive average ion velocity and ion current density corresponding to each spatial point includes: For each instant, the torque generated per unit area at each spatial point is calculated using the following formula based on the combined average ion velocity and ion current density corresponding to that spatial point. T A : in, T A The dynamic torque density represents the torque generated by the spatial point per unit area; The ion current density; Mass of a single ion; L The lever arm that generates torque for the ion velocity at the spatial point is calculated based on the distance between the spatial point and the thruster axis and the direction of the ion velocity.

8. The method according to claim 2, characterized in that, The step of spatially integrating the dynamic torque density corresponding to all the spatial points to obtain the dynamic torque of the thruster includes: For each instant, the dynamic torque density corresponding to all the spatial points is integrated over the entire plane under test to obtain the curve of the total torque of the thruster changing with time, and the curve of the total torque changing with time is determined as the dynamic torque of the thruster.

9. A plasma propulsion dynamic torque measuring device, characterized in that, The thruster, fiber optic collimator, Faraday probe, and corresponding translation slide are housed within a vacuum chamber. The incident laser and sheet laser elements of the laser have been aligned, and the relative positions of the Faraday probe and the thruster are aligned. The system includes: The calibration module is used to calibrate the calibration relationship between the total fluorescence intensity and ion current density of the thruster in response to the operation of the thruster and the laser, using the current measurement results of the Faraday probe, fixing the laser wavelength of the laser and measuring the first time-varying data of the fluorescence intensity distribution in the beam of the thruster changing with time and the second time-varying data of the plasma emission intensity of the spatial point in the beam changing with time. The alignment module is used to adjust different laser wavelengths and scan fluorescence signals under different laser wavelengths. Based on the fluorescence signals, the time axis of the first time-varying data under different laser wavelengths is aligned using the second time-varying data to obtain the fluorescence intensity curve corresponding to the laser wavelength at each spatial point at each moment. The calculation module is used to calculate the ion velocity distribution function of each spatial point at each time according to the fluorescence intensity curve corresponding to the laser wavelength, and to calculate the ion current density based on the ion velocity distribution function using the calibration relationship and the integral value of the fluorescence intensity at the laser wavelength. The integration module is used to measure the ion velocity distribution function in another perpendicular direction by changing the velocity measurement direction and synthesize it to obtain the comprehensive average ion velocity. Based on the comprehensive average ion velocity and the ion current density corresponding to each spatial point, the dynamic torque density is calculated. Based on the dynamic torque density corresponding to all spatial points, the dynamic torque of the thruster is obtained by spatial integration.

10. An electronic device, comprising a memory and a processor, wherein the memory stores a computer program executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method described in any one of claims 1 to 8.

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