Micro pulse electric thruster element impulse measuring device and method

Abstract

The invention discloses a micro pulse electric thruster element impulse measuring device and method, and relates to the technical field of electric thrusters, and the device comprises piezoelectric ceramic which is located at an outlet of a micro pulse electric thruster and is used for receiving plasma plume generated by the micro pulse electric thruster, the pressure generated by the plasma plume on the surface of the piezoelectric ceramic is converted into an original electric signal; and the element impulse calculation unit is connected with the piezoelectric ceramic and is used for calculating the element impulse of the micro pulse electric thruster according to the original electric signal, the thickness of the piezoelectric ceramic, the piezoelectric constant of the piezoelectric ceramic and the effective cross section area of the plasma plume on the surface of the piezoelectric ceramic. According to the invention, the piezoelectric ceramic is used as a measurement device for the element impulse of the micro pulse electric thruster, the sensitivity of the element impulse measurement device is improved, and the complexity of the structure of the device is reduced at the same time.

Description

Technical Field

[0001] The present application relates to the technical field of electric thrusters, and particularly to a device and method for measuring the specific impulse of a micro pulsed electric thruster. Background Art

[0002] The micro pulsed electric thruster has the characteristics of low power consumption, simple structure, light weight, high specific impulse, long life, high reliability and high control accuracy. It has strong competitiveness and application prospects in the field of micro and nano satellites, and is very suitable for propulsion tasks such as orbital maneuvering, attitude control, drag compensation and formation flight of modern micro and nano satellites. The specific impulse is one of the core indicators of the micro pulsed electric thruster, which can truly and intuitively reflect the changes in the performance of the thruster caused by the electrical parameters and structural parameters of the thruster, and provide necessary technical means for the design and parameter selection of the thruster. The measurement of the specific impulse is one of the test items that must be carried out during the development of the micro pulsed electric thruster.

[0003] Traditional micro pulsed electric thrusters often use a thrust stand as the device for measuring their specific impulse. The structure of the thrust stand is complex and not easy to disassemble and assemble. At the same time, for pulsed electric thrusters, since the thrust stand cannot quickly return to the static relaxation state after measuring a single pulse, a long time is required to wait for the thrust stand to recover between two measurements of the specific impulse. This results in the thrust stand being unable to measure the specific impulse of a micro pulsed electric thruster under a single pulse under the condition of too high discharge frequency. Summary of the Invention

[0004] The purpose of the present application is to provide a device and method for measuring the specific impulse of a micro pulsed electric thruster, which uses a piezoelectric ceramic as the measuring element of the specific impulse of the micro pulsed electric thruster, improves the sensitivity of the specific impulse measuring device, and reduces the complexity of the device structure at the same time.

[0005] To achieve the above purpose, the present application provides the following solutions:

[0006] In the first aspect, the present application provides a device for measuring the specific impulse of a micro pulsed electric thruster, including:

[0007] A piezoelectric ceramic, located at the outlet of the micro pulsed electric thruster, for receiving the plasma plume generated by the micro pulsed electric thruster and converting the pressure generated by the plasma plume on the surface of the piezoelectric ceramic into an original electrical signal;

[0008] A specific impulse calculation unit, connected to the piezoelectric ceramic, for calculating the specific impulse of the micro pulsed electric thruster according to the original electrical signal, the thickness of the piezoelectric ceramic, the piezoelectric constant of the piezoelectric ceramic, and the effective cross-sectional area of the plasma plume on the surface of the piezoelectric ceramic.

[0009] Optionally, the optimal distance between the outlet of the micro pulsed thruster and the piezoelectric ceramic is determined in advance according to experiments.

[0010] Optionally, the area of the piezoelectric ceramic is larger than the maximum cross-sectional area of the plasma plume at the optimal distance.

[0011] Optionally, the micro pulsed thruster specific impulse measurement device further includes a capacitor;

[0012] The capacitor is connected in parallel with the piezoelectric ceramic, and the capacitor is used to filter out the environmental noise in the original electrical signal.

[0013] Optionally, the size of the capacitor is determined in advance according to the frequency of the environmental noise.

[0014] Optionally, the specific impulse calculation unit is further configured to: acquire the internal electrical signal of the micro pulsed thruster; compare the waveforms of the internal electrical signal and the original electrical signal to obtain waveform synchronism; if the waveform synchronism is less than a first set threshold, recalculate the specific impulse, and if the waveform synchronism is greater than or equal to the first set threshold, output the calculation result of the specific impulse as the final result.

[0015] In a second aspect, the present application provides a method for measuring the specific impulse of a micro pulsed thruster, which is applied to the above-mentioned micro pulsed thruster specific impulse measurement device, and includes:

[0016] Using a piezoelectric ceramic to receive the plasma plume generated by the micro pulsed thruster, and converting the pressure generated by the plasma plume on the surface of the piezoelectric ceramic into an original electrical signal;

[0017] Using a specific impulse calculation unit to obtain the specific impulse of the micro pulsed thruster according to the original electrical signal, the thickness of the piezoelectric ceramic, the piezoelectric constant of the piezoelectric ceramic, and the effective cross-sectional area of the plasma plume on the surface of the piezoelectric ceramic.

[0018] Optionally, before using a piezoelectric ceramic to receive the plasma plume generated by the micro pulsed thruster and converting the pressure generated by the plasma plume on the surface of the piezoelectric ceramic into an original electrical signal, the method for measuring the specific impulse of the micro pulsed thruster further includes:

[0019] Determining the optimal distance between the outlet of the micro pulsed thruster and the piezoelectric ceramic according to experiments;

[0020] Acquiring the maximum cross-sectional area of the plasma plume at the optimal distance;

[0021] Obtaining the area of the piezoelectric ceramic according to the maximum cross-sectional area; the area of the piezoelectric ceramic is larger than the maximum cross-sectional area;

[0022] Based on the optimal distance and the area of the piezoelectric ceramic, a piezoelectric ceramic with a corresponding area is arranged at the outlet of the micro pulsed thruster.

[0023] Optionally, obtaining the maximum cross-sectional area of the plasma plume at the optimal distance specifically includes:

[0024] Coat a pressure-sensitive color-changing material on the first surface of the piezoelectric ceramic material to obtain a test sample; the color-changing area of the pressure-sensitive color-changing material is proportional to the pressure received by the first surface;

[0025] Place the test sample at the optimal distance;

[0026] Set the maximum input voltage for the micro pulsed thruster; under the action of the maximum input voltage, the micro pulsed thruster generates a first plasma plume; the first surface receives the first plasma plume, and under the action of the first plasma plume, the color-changing material on the first surface obtains a first color-changing area;

[0027] Obtain the maximum cross-sectional area according to the first color-changing area.

[0028] Optionally, the original electrical signal is the voltage across the piezoelectric ceramic;

[0029] Adopt an elementary impulse calculation unit to obtain the elementary impulse of the micro pulsed thruster according to the original electrical signal, the thickness of the piezoelectric ceramic, the piezoelectric constant of the piezoelectric ceramic, and the effective cross-sectional area of the plasma plume on the surface of the piezoelectric ceramic, specifically including:

[0030] Obtain the thickness of the piezoelectric ceramic and the piezoelectric constant of the piezoelectric ceramic;

[0031] According to the voltage across the piezoelectric ceramic, the thickness of the piezoelectric ceramic, the piezoelectric constant of the piezoelectric ceramic, and the effective cross-sectional area, calculate the elementary impulse through the following formula:

[0032]

[0033] where I is the elementary impulse; Δt is the time element; n is the ratio of the total discharge time of the micro pulsed thruster under a single pulse to the time element Δt; e is the permittivity; V i is the voltage across the piezoelectric ceramic in the i-th time element; A is the effective cross-sectional area; d 33 is the piezoelectric constant of the piezoelectric ceramic; l is the thickness of the piezoelectric ceramic.

[0034] According to the specific embodiments provided in this application, the following technical effects are achieved:

[0035] This application provides a device and method for measuring the elemental impulse of a micro pulsed thruster. By using piezoelectric ceramics as the measuring element for the elemental impulse of the micro pulsed thruster, the sensitivity of the elemental impulse measuring device is improved, and at the same time, the complexity of the device structure is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of this application or in the related art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of this application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0037] Figure 1 It is a schematic diagram of the functional modules of a device for measuring the elemental impulse of a micro pulsed thruster provided in an embodiment of this application;

[0038] Figure 2 It is a schematic diagram of the overall structure of a device for measuring the elemental impulse of a micro pulsed thruster provided in an embodiment of this application;

[0039] Figure 3 It is a schematic diagram of the hardware framework of a device for measuring the elemental impulse of a micro pulsed thruster provided in an embodiment of this application;

[0040] Figure 4 It is a schematic diagram of the process flow of a method for measuring the elemental impulse of a micro pulsed thruster provided in an embodiment of this application;

[0041] Figure 5 It is provided in an embodiment of this application Figure 4 The schematic diagram of the process flow before step 401;

[0042] Figure 6 It is provided in an embodiment of this application Figure 5 The detailed process flow diagram of step 502;

[0043] Figure 7 It is a schematic diagram of the color display results formed by the pressure color-changing material on the surface of the piezoelectric ceramic under different input voltages provided in an embodiment of this application;

[0044] Figure 8 It is a schematic diagram of the elemental impulse calculation results and error conditions of the micro pulsed thruster under different input voltages provided in an embodiment of this application.

[0045] Reference numerals: 101 - piezoelectric ceramic, 102 - elemental impulse calculation unit, 201 - capacitor, 301 - micro pulsed thruster, 302 - bracket, 303 - oscilloscope, 3031 - voltage probe, 3032 - current probe. Detailed implementation manners

[0046] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0047] The present application provides a device and method for measuring the elemental impulse of a micro pulsed thruster. By using a piezoelectric ceramic as the measuring element for the elemental impulse of the micro pulsed thruster, the sensitivity of the elemental impulse measuring device is improved, and at the same time, the complexity of the device structure is reduced.

[0048] To make the above objects, features, and advantages of the present application more obvious and understandable, the present application will be further described in detail below with reference to the accompanying drawings and specific implementation manners.

[0049] In an exemplary embodiment, as Figure 1 shown, a device for measuring the elemental impulse of a micro pulsed thruster is provided. The device for measuring the elemental impulse of the micro pulsed thruster includes: a piezoelectric ceramic 101 and an elemental impulse calculation unit 102. Among them, the piezoelectric ceramic 101 is located at the outlet of the micro pulsed thruster. The piezoelectric ceramic 101 is used to receive the plasma plume generated by the micro pulsed thruster and convert the pressure generated by the plasma plume on the surface of the piezoelectric ceramic 101 into an original electrical signal. The elemental impulse calculation unit 102 is connected to the piezoelectric ceramic 101. The elemental impulse calculation unit 102 is used to calculate the elemental impulse of the micro pulsed thruster according to the original electrical signal, the thickness of the piezoelectric ceramic 101, the piezoelectric constant of the piezoelectric ceramic 101, and the effective cross-sectional area of the plasma plume on the surface of the piezoelectric ceramic 101.

[0050] Piezoelectric ceramics have the characteristics of a large measurement range and high sensitivity, and can be used to measure a micro-pulse electric thruster, which requires a probe with microsecond-level sensitivity. The piezoelectric ceramic 101 can convert the pressure signal applied to its surface into an electrical signal, and the pressure applied to the surface of the piezoelectric ceramic 101 can be calculated according to the collected electrical signal through a series of conversion formulas. The area of the piezoelectric ceramic 101 should be larger than the cross-sectional area of the plasma plume on the same plane of the piezoelectric ceramic to ensure the accuracy of the elemental impulse measurement. At the same time, the piezoelectric ceramic 101 should not be too close to the outlet of the micro-pulse electric thruster to prevent the plasma plume from not developing fully; nor should it be too far away to prevent the cross-sectional area of the plasma plume at the piezoelectric ceramic 101 from being too large or the plasma plume from not reaching the surface of the piezoelectric ceramic 101. In this embodiment, the optimal distance between the outlet of the micro-pulse electric thruster and the piezoelectric ceramic 101 is determined in advance according to experiments. The area of the piezoelectric ceramic 101 is larger than the maximum cross-sectional area of the plasma plume at the optimal distance.

[0051] In another exemplary embodiment, the elemental impulse calculation unit 102 is further configured to: acquire the internal electrical signal of the micro-pulse electric thruster; compare the waveforms of the internal electrical signal and the original electrical signal to obtain waveform synchronization; if the waveform synchronization is less than the first set threshold, recalculate the elemental impulse, and if the waveform synchronization is greater than or equal to the first set threshold, output the calculation result of the elemental impulse as the final result.

[0052] In an exemplary embodiment, as Figure 2 shown, the micro-pulse electric thruster elemental impulse measurement device further includes a capacitor 201. The capacitor 201 is connected in parallel with the piezoelectric ceramic 101. The capacitor 201 is used to filter out environmental noise in the original electrical signal. The size of the capacitor 201 is determined in advance according to the frequency of the environmental noise. Due to the high sensitivity of the piezoelectric ceramic 101, it is prone to be interfered by high-frequency oscillations in the external environment, resulting in waveform distortion. Connecting a small capacitor in parallel at both ends of the piezoelectric ceramic 101 can filter out high-frequency noise interference. The size of the capacitor matches the frequency of the external interference.

[0053] In an exemplary embodiment, as Figure 3 shown, the piezoelectric ceramic 101 is disposed at a distance h from the outlet of the micro-pulse electric thruster 301. h should ensure both the full development of the plasma plume generated by the thruster and the arrival of the plasma plume at this position. In this embodiment, h is set to 3 cm. The bracket 302 is used to fix the piezoelectric ceramic 101.

[0054] The capacitor 201 is connected in parallel with the piezoelectric ceramic 101. In the vacuum chamber, due to the presence of the air pump, the vacuum chamber will inevitably vibrate, which causes the piezoelectric ceramic 101 to vibrate accordingly, forming a regular high-frequency waveform. The capacitor 201 can filter out high-frequency clutter and retain the waveform to be measured. The size of the capacitor 201 should be selected to match the environmental noise frequency. The capacitance value should not be too large, as this may filter out the waveform of the output voltage generated by the plasma plume hitting the piezoelectric ceramic 101. For audible noise with a frequency range of 20 Hz - 2000 Hz, the capacitance size is correspondingly set to 0.1 μF - 0.47 μF.

[0055] In this embodiment, the primitive impulse calculation unit 102 uses the oscilloscope 303 to obtain the original electrical signal and the internal electrical signal of the micro pulsed thruster 301. Since the capacitor 201 is connected in parallel with the piezoelectric ceramic 101, the oscilloscope 303 measures the voltage across the capacitor 201 through the voltage probe 3031, and thus the voltage across the piezoelectric ceramic 101 can be obtained. The current probe 3032 of the oscilloscope 303 is used to obtain the current inside the micro pulsed thruster 301. By comparing the voltage waveform across the piezoelectric ceramic 101 and the current waveform inside the micro pulsed thruster 301, the waveform synchronization is obtained, and it can be determined whether the calculated primitive impulse is generated due to the plasma plume emitted by the micro pulsed thruster 301 based on the waveform synchronization.

[0056] In an exemplary embodiment, as Figure 4 shown, a method for measuring the primitive impulse of a micro pulsed thruster is provided. This method is executed by a computer device, and specifically, it can be executed alone by a computer device such as a terminal or a server, or jointly executed by a terminal and a server. It includes: Step 401, using a piezoelectric ceramic to receive the plasma plume generated by the micro pulsed thruster, and converting the pressure generated by the plasma plume on the surface of the piezoelectric ceramic into an original electrical signal. Step 402, using the primitive impulse calculation unit to obtain the primitive impulse of the micro pulsed thruster according to the original electrical signal, the thickness of the piezoelectric ceramic, the piezoelectric constant of the piezoelectric ceramic, and the effective cross-sectional area of the plasma plume on the surface of the piezoelectric ceramic.

[0057] In an exemplary embodiment, as Figure 5 described, before the above step 401, the method for measuring the primitive impulse of a micro pulsed thruster further includes: Step 501, determining the optimal distance between the outlet of the micro pulsed thruster and the piezoelectric ceramic according to experiments. Step 502, obtaining the maximum cross-sectional area of the plasma plume at the optimal distance. Step 503, obtaining the area of the piezoelectric ceramic according to the maximum cross-sectional area; the area of the piezoelectric ceramic is larger than the maximum cross-sectional area. Step 504, based on the optimal distance and the area of the piezoelectric ceramic, setting the piezoelectric ceramic with the corresponding area at the outlet of the micro pulsed thruster.

[0058] In an exemplary embodiment, as Figure 6 shown, the above step 502 can be replaced by the following steps: Step 601, coating a pressure-sensitive color-changing material on the first surface of the piezoelectric ceramic material to obtain a test sample; the color-changing area of the pressure-sensitive color-changing material is proportional to the pressure received by the first surface. Step 602, placing the test sample at the optimal distance. Step 603, setting the maximum input voltage for the micro pulsed thruster; under the action of the maximum input voltage, the micro pulsed thruster generates a first plasma plume; the first surface receives the first plasma plume, and under the action of the first plasma plume, the color-changing material on the first surface obtains a first color-changing area. Step 604, obtaining the maximum cross-sectional area according to the first color-changing area.

[0059] The pressure-sensitive color-changing material changes color according to the magnitude of the force applied to it, and the depth of the color is related to the magnitude of the force. In an exemplary embodiment, a very thin layer of pressure-sensitive color-changing material is coated on the surface of the piezoelectric ceramic, and different input voltages are set for the micro pulsed thruster. The color-changing results formed by the pressure-sensitive color-changing material on the surface of the piezoelectric ceramic 101 are as Figure 7 shown. For different input voltages, the color-changing areas of the pressure-sensitive color-changing material on the surface of the piezoelectric ceramic are different. The difference in this area is caused by the differences in both the input voltage and the discharge instability. The greater the input voltage, the larger the color-changing area formed by the pressure-sensitive color-changing material, and vice versa. The maximum color-changing area 701 of the pressure-sensitive color-changing material corresponds to the maximum input voltage, and the minimum color-changing area 702 of the pressure-sensitive color-changing material corresponds to the minimum input voltage. The position of the piezoelectric ceramic will determine the area of the plume remaining on its surface, and it is only necessary to ensure that the color-changing area of the pressure-sensitive color-changing material is smaller than the area of the piezoelectric ceramic.

[0060] In an exemplary embodiment, the original electrical signal is the voltage across the piezoelectric ceramic. The above step 402 can be replaced by the following steps: obtaining the thickness of the piezoelectric ceramic and the piezoelectric constant of the piezoelectric ceramic; calculating the elementary impulse through the following formula according to the voltage across the piezoelectric ceramic, the thickness of the piezoelectric ceramic, the piezoelectric constant of the piezoelectric ceramic, and the effective cross-sectional area:

[0061]

[0062] where I is the elementary impulse; Δt is the time element; n is the ratio of the total discharge time of the micro pulsed thruster under a single pulse to the time element Δt; e is the dielectric constant; V i is the voltage across the piezoelectric ceramic in the i-th time element; A is the effective cross-sectional area; d 33 is the piezoelectric constant of the piezoelectric ceramic; l is the thickness of the piezoelectric ceramic.

[0063] The magnitude of the elemental impulse measured using piezoelectric ceramics is related to the effective cross-sectional area formed by the plasma plume on the surface of the piezoelectric ceramics. In an exemplary embodiment, a computer vision method is used to calculate this effective cross-sectional area. The specific method is as follows: Obtain the color-developing image formed by the plasma plume on the surface of the piezoelectric ceramics, then perform noise reduction and other processing on the obtained color-developing image, and finally calculate the actual area of the color-developing image based on the number of pixels and pixel size of the preprocessed image, which is the above-mentioned effective cross-sectional area.

[0064] In an exemplary embodiment, the elemental impulse is calculated five times respectively under different feeding voltages, and the mean value of these five elemental impulse data is used as the calculation result of the final elemental impulse, and the standard deviation of these five elemental impulse data is used as the error evaluation index. The calculation results and error conditions of the elemental impulse of the micro-pulse thruster under different feeding voltages are as Figure 8 shown. It can be seen that the deviation of the elemental impulse results measured multiple times under the same feeding voltage is small. Therefore, the method for measuring the elemental impulse of the micro-pulse thruster proposed in this application has high accuracy.

[0065] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use, and processing of relevant data need to comply with relevant regulations.

[0066] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, database, or other medium used in the various embodiments provided in the present application can include at least one of non-volatile and volatile memories. Non-volatile memories can include read-only memory (ROM), magnetic tapes, floppy disks, flash memories, optical memories, high-density embedded non-volatile memories, resistive random-access memories (ReRAM), magnetoresistive random-access memories (MRAM), ferroelectric random-access memories (FRAM), phase change memories (PCM), graphene memories, etc. Volatile memories can include random access memory (RAM) or external cache memories, etc. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0067] The databases involved in the various embodiments provided in the present application can include at least one of relational databases and non-relational databases. Non-relational databases can include distributed databases based on blockchain, etc., without limitation. The processors involved in the various embodiments provided in the present application can be general-purpose processors, central processors, graphics processors, digital signal processors, programmable logic devices, data processing logics based on quantum computing, etc., without limitation.

[0068] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0069] Specific examples are used in this article to elaborate on the principles and implementation manners of the present application. The descriptions of the above embodiments are only used to help understand the method and its core idea of the present application; at the same time, for those of ordinary skill in the art, according to the idea of the present application, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. A device for measuring the impulse of a micro pulse electric thruster, characterized in that: The micro pulse electric thruster element impulse measuring device comprises: A piezoelectric ceramic is located at the outlet of the micro pulse electric thruster and is used to receive the plasma plume generated by the micro pulse electric thruster and convert the pressure generated by the plasma plume on the surface of the piezoelectric ceramic into an original electrical signal; A meta-impulse calculation unit is connected to the piezoelectric ceramic and is used to calculate the meta-impulse of the micro pulse electric thruster according to the original electrical signal, the thickness of the piezoelectric ceramic, the piezoelectric constant of the piezoelectric ceramic and the effective cross-sectional area of ​​the plasma plume on the surface of the piezoelectric ceramic.

2. The micro pulse electric thruster element impulse measuring device according to claim 1 is characterized in that: The optimal distance between the outlet of the micro pulse electric thruster and the piezoelectric ceramic is determined in advance based on experiments.

3. The micro pulse electric thruster element impulse measuring device according to claim 2 is characterized in that: The area of ​​the piezoelectric ceramic is larger than the maximum cross-sectional area of ​​the plasma plume at the optimal distance.

4. The micro pulse electric thruster element impulse measuring device according to claim 1 is characterized in that: The micro pulse electric thruster element impulse measuring device also includes a capacitor; The capacitor is connected in parallel with the piezoelectric ceramic, and is used to filter out environmental noise in the original electrical signal.

5. The device for measuring the impulse of a micro pulse electric thruster according to claim 4, characterized in that: The size of the capacitor is determined in advance according to the frequency of the environmental noise.

6. The micro pulse electric thruster impulse measuring device according to claim 1 is characterized in that: The meta-impulse calculation unit is also used to: obtain the internal electrical signal of the micro-pulse electric thruster; compare the waveform of the internal electrical signal with the waveform of the original electrical signal to obtain waveform synchronization; if the waveform synchronization is less than a first set threshold, recalculate the meta-impulse; if the waveform synchronization is greater than or equal to the first set threshold, output the calculation result of the meta-impulse as the final result.

7. A method for measuring the impulse of a micro pulse electric thruster, applied to the micro pulse electric thruster impulse measuring device according to any one of claims 1 to 6, characterized in that: The micro pulse electric thruster element impulse measurement method comprises: Using piezoelectric ceramics to receive the plasma plume generated by the micro pulse electric thruster, and converting the pressure generated by the plasma plume on the surface of the piezoelectric ceramics into an original electrical signal; A primitive impulse calculation unit is used to obtain the primitive impulse of the micro pulse electric thruster according to the original electrical signal, the thickness of the piezoelectric ceramic, the piezoelectric constant of the piezoelectric ceramic and the effective cross-sectional area of ​​the plasma plume on the surface of the piezoelectric ceramic.

8. The method for measuring the impulse of a micro pulse electric thruster according to claim 7, characterized in that: Before using piezoelectric ceramics to receive the plasma plume generated by the micro pulse electric thruster and converting the pressure generated by the plasma plume on the surface of the piezoelectric ceramics into an original electrical signal, the micro pulse electric thruster element impulse measurement method further includes: Determine the optimal distance between the outlet of the micro pulse electric thruster and the piezoelectric ceramic according to experiments; obtaining a maximum cross-sectional area of ​​the plasma plume at the optimal distance; Obtaining the area of ​​the piezoelectric ceramic according to the maximum cross-sectional area; the area of ​​the piezoelectric ceramic is greater than the maximum cross-sectional area; Based on the optimal distance and the area of ​​the piezoelectric ceramic, a piezoelectric ceramic with a corresponding area is arranged at the outlet of the micro pulse electric thruster.

9. The method for measuring the impulse of a micro pulse electric thruster according to claim 8, characterized in that: Obtaining the maximum cross-sectional area of ​​the plasma plume at the optimal distance specifically includes: Coating a pressure-chromic material on a first surface of a piezoelectric ceramic material to obtain a test sample; the color development area of ​​the pressure-chromic material is proportional to the pressure on the first surface; placing the test sample at the optimal distance; A maximum feed voltage is set for the micro pulse electric thruster; under the action of the maximum feed voltage, the micro pulse electric thruster generates a first plasma plume; the first surface receives the first plasma plume, and under the action of the first plasma plume, the color-changing material on the first surface obtains a first color-developing area; The maximum cross-sectional area is obtained according to the first color rendering area.

10. The method for measuring the impulse of a micro pulse electric thruster according to claim 7, characterized in that: The original electrical signal is the voltage across the piezoelectric ceramic; The element impulse calculation unit is used to obtain the element impulse of the micro pulse electric thruster according to the original electrical signal, the thickness of the piezoelectric ceramic, the piezoelectric constant of the piezoelectric ceramic and the effective cross-sectional area of ​​the plasma plume on the surface of the piezoelectric ceramic, specifically including: Obtaining the thickness of the piezoelectric ceramic and the piezoelectric constant of the piezoelectric ceramic; According to the voltage across the piezoelectric ceramic, the thickness of the piezoelectric ceramic, the piezoelectric constant of the piezoelectric ceramic and the effective cross-sectional area, the elementary impulse is calculated by the following formula: Where I is the impulse; Δt is the time element; n is the ratio of the total discharge time of the micro pulse electric thruster under a single pulse to the time element Δt; e is the dielectric constant; V i is the voltage across the piezoelectric ceramic in the i-th time unit; A is the effective cross-sectional area; d 33 is the piezoelectric constant of the piezoelectric ceramic; l is the thickness of the piezoelectric ceramic.

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