Electrospray thruster regulation method and apparatus

Abstract

The embodiment of the application provides a kind of electro-spray thruster regulation method and device, the method comprises: according to target thrust value F* and calibration data, calculate initial acceleration voltage, determine the emission current corresponding to current acceleration voltage, and based on the first preset relationship of predicted thrust value, emission current and acceleration voltage, calculate the predicted thrust value F under the voltage;Judge whether the difference between predicted thrust value F and target thrust value F* satisfies the second preset relationship, if not satisfied, then reset current acceleration voltage and repeat the above calculation and judging steps, if satisfied, then end the thrust regulation.The application realizes the regulation and control not dependent on direct thrust measurement by obtaining electrical parameters in real time and using the known relationship between thrust and electrical parameters for iterative optimization, solves the problem of thrust regulation caused by the difficulty of accurate monitoring and feedback of microampere-level working current of electro-spray thruster in orbit.

Description

Technical Field

[0001] This invention relates to the field of space electric propulsion technology, and in particular to a method and apparatus for controlling an electro-spray thruster. Background Technology

[0002] Electrospray thrusters, as a novel type of micro-electric propulsion device, have become an important development direction for micro- and nano-satellite propulsion systems due to their significant advantages such as small size, light weight, high performance, and high efficiency. Currently, the mainstream technical solution for electrospray thrusters uses porous materials as the emitter and passively supplies propellant using capillary force. These thrusters typically operate in pure ion mode. Their basic principle is: by applying a high-voltage electric field between the emitter and extractor, an ultra-high field strength is generated at the emitter tip, thereby directly ionizing and accelerating the extraction of ions or ion clusters, forming jet thrust.

[0003] In the field of conventional electric propulsion, Hall thrusters and ion thrusters have relatively mature thrust control technologies due to their stable volt-ampere characteristics and milliampere to ampere-level operating currents. They generally employ variable flow or voltage control schemes based on closed-loop feedback of the operating current. However, for electrospray thrusters, these mature strategies face severe technical bottlenecks. On the one hand, due to the passive propellant supply, thrust control cannot be achieved by actively adjusting the flow rate. On the other hand, the operating current of electrospray thrusters is extremely weak, typically only in the range of a few microamperes to tens of microamperes. This current level is easily confused with the satellite platform's background noise and stray currents in the space environment, resulting in high-precision online current monitoring that is not only costly but also has an extremely low signal-to-noise ratio, making it difficult to use as a reliable feedback signal.

[0004] To address the aforementioned technical shortcomings, there is an urgent need to develop a model predictive control-based electrospray thruster control scheme. Summary of the Invention

[0005] In view of this, embodiments of the present invention provide an electro-spray thruster control method and apparatus to solve the thrust control problem caused by the difficulty in accurately monitoring and feeding back the microampere-level operating current of the electro-spray thruster on orbit.

[0006] In a first aspect, embodiments of the present invention provide a method for controlling an electro-spray thruster, comprising: Step 101: Calculate the initial acceleration voltage based on the target thrust value F* and the calibration data. The target thrust value F* is the thrust value that the electro-spray thruster needs to generate, and the calibration data is a table showing the correspondence between the thrust value and the acceleration voltage. Step 102: Determine the launch current corresponding to the current acceleration voltage, and calculate the predicted thrust value F under the current acceleration voltage based on the first preset relationship between the predicted thrust value, launch current and acceleration voltage. The first preset relationship is a fitted exponential relationship. Step 103: Determine whether the difference between the predicted thrust value F and the target thrust value F* satisfies the second preset relationship; If not satisfied, the current acceleration voltage is reset, and steps 102 and 103 above are executed again to determine whether the predicted thrust value F corresponding to the current acceleration voltage satisfies the second preset relationship. If the conditions are met, thrust control will end.

[0007] Secondly, embodiments of the present invention provide an electro-spray thruster control device, comprising: The initial calculation unit is used to calculate the initial acceleration voltage based on the target thrust value F* and the calibration data. The target thrust value F* is the thrust value that the electro-spray thruster needs to generate, and the calibration data is a table showing the correspondence between the thrust value and the acceleration voltage. The thrust calculation unit is used to determine the emission current corresponding to the current acceleration voltage, and to calculate the predicted thrust value F under the current acceleration voltage based on the first preset relationship between the predicted thrust value, the emission current and the acceleration voltage. The first preset relationship is a fitted exponential relationship. The judgment unit is used to determine whether the difference between the predicted thrust value F and the target thrust value F* satisfies the second preset relationship; If not satisfied, the current acceleration voltage is reset, and the thrust value calculation unit and the judgment unit re-determine whether the predicted thrust value F corresponding to the current acceleration voltage satisfies the second preset relationship. If the conditions are met, thrust control will end.

[0008] The technical solution of this invention calculates the initial acceleration voltage based on the target thrust value F* and calibration data, determines the launch current corresponding to the current acceleration voltage, and calculates the predicted thrust value F under the voltage based on a first preset relationship between the predicted thrust value, launch current, and acceleration voltage. It then determines whether the difference between the predicted thrust value F and the target thrust value F* satisfies a second preset relationship. If not, the current acceleration voltage is reset and the above calculation and judgment steps are repeated. If the relationship is satisfied, thrust control ends. This invention achieves control without relying on direct thrust measurement by acquiring electrical parameters in real time and using the known relationship between thrust and electrical parameters for iterative optimization. This solves the thrust control problem caused by the difficulty in accurately monitoring and feeding back the microampere-level operating current of electrospray thrusters in orbit. Attached Figure Description

[0009] To more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0010] Figure 1 This is a flowchart of the electro-spray thruster control method provided in the embodiments of the present invention; Figure 2 This is a hardware architecture diagram of the electronic device provided in an embodiment of the present invention; Figure 3 This is a structural diagram of the electro-spray thruster control device provided in an embodiment of the present invention; Figure 4 These are the volt-ampere characteristic test results and fitting curves provided in the embodiments of the present invention; Figure 5 These are the thrust test results and fitting curves provided in the embodiments of the present invention; Figure 6 This is a FU data table provided in an embodiment of the present invention. Detailed Implementation

[0011] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0012] Electrospray thrusters are advanced micro-propulsion systems that utilize a strong electric field to extract conductive liquids, such as ionic liquids, from micro-nozzles or porous emitters, breaking them into tiny droplets or ions carrying charges. These charged particles are accelerated and ejected in an electrostatic field, generating minute but precise thrust based on the conservation of momentum. This type of thruster boasts significant advantages, including simple structure, no moving parts, low power consumption, high specific impulse, and precise thrust control. It is suitable for missions requiring extremely high thrust resolution, such as orbit maintenance, attitude control, formation flying, and space gravitational wave detection for micro and nanosatellites.

[0013] Figure 1 This is a flowchart of the electro-spray thruster control method provided in an embodiment of the present invention, as follows: Figure 1 As shown, the method includes the following steps: Step 101: Calculate the initial acceleration voltage based on the target thrust value F* and the calibration data. The target thrust value F* is the thrust value that the electro-spray thruster needs to generate, and the calibration data is a table showing the correspondence between the thrust value and the acceleration voltage.

[0014] Step 102: Determine the emission current corresponding to the current acceleration voltage, and calculate the predicted thrust value F under the current acceleration voltage based on the first preset relationship between the predicted thrust value, emission current and acceleration voltage. The first preset relationship is a fitted exponential relationship.

[0015] Step 103: Determine whether the difference between the predicted thrust value F and the target thrust value F* satisfies the second preset relationship.

[0016] If so, proceed to step 104; If not, proceed to step 105.

[0017] Step 104: End thrust control.

[0018] Step 105: Reset the current acceleration voltage.

[0019] Proceed to step 102.

[0020] The following will be about Figure 1 The steps of the electro-spray thruster control method are explained in detail below. First, before proceeding to step 101, it is necessary to construct a thrust model for the electro-spray thruster. The establishment of the thrust control model is explained below: Based on the working principle of electrospray thrusters and the physical meaning of thrust, its thrust can be specifically expressed as the sum of the momentum of the jet of ions or ion clusters ejected per unit time, which can be expressed by the following formula: in, This refers to the mass flow rate of different component ions or ion clusters. It is the sum of the momentum of different component ions or ion clusters. This refers to the divergence angle of different component ions or ion clusters. For electrospray thrusters, the divergence angles of different component ions or ion clusters are basically the same and can be roughly considered as the same value. Therefore, the above formula can be rewritten as:

[0021] According to the law of conservation of energy and the continuity equation, we know that: in, Here, U represents the mass of different component ions or ion clusters, U is the accelerating voltage, and e is the elementary charge.

[0022] Solving the above equations simultaneously, we can obtain the following formula: Write the current of each component as the emission current I and the component percentage. The form of the product, i.e. The thrust formula can be further rewritten as a thrust model based on the accelerating voltage U and the launch current I: thrust coefficient Set it using the following formula: The thrust formula is further simplified to: Thus, the modeling formula for the thrust value in this embodiment of the invention is obtained. The above formula is further rewritten into a single-variable representation based on voltage. Specifically, in pure ion mode, the ion emission current of the electrospray thruster can be calculated according to the ion evaporation theory as follows: In the formula, E is the electric field strength at the tip of the Taylor cone of the electro-spray thruster, T is the temperature of the ionic liquid working fluid of the electro-spray thruster, σ is the surface charge of the Taylor cone, and k is the electric field strength at the tip of the Taylor cone. B h and are Boltzmann constant and Planck constant, respectively.

[0023] make , Then the ion emission current can be written as:

[0024] Further derivation of the relationship between the electric field intensity E at the tip of the Taylor cone and the accelerating voltage U is needed. Based on the principle of close-range action, taking local boundary conditions, the integral solution of the Laplace equation explicitly containing the curvature k of the equipotential surface is directly obtained, yielding the analytical solution of the electric field intensity E at the tip of the Taylor cone: In the formula, D is the distance between the emitter and lead-out electrodes of the electrospray thruster. From the above formula, it can be seen that, with the thruster structure unchanged (i.e., k and D unchanged), the electric field strength E at the Taylor cone tip and the accelerating voltage U have a linear relationship. Let... ,have .

[0025] Will Substitution In the middle, there are: make ,have C E Primarily related to physical properties and the electric field distribution characteristics of equipotential surface curvature, these are named field shape parameters. Substituting them into the linear control model of the thrust formula, we have: make Then the thrust formula is further simplified to: C sPrimarily related to physical properties and structural parameters affecting the plume divergence angle, these are named configuration parameters. The above equation contains only the independent variable U, the dependent variable F, and the coefficient C. E Cs can be used as a single-variable nonlinear control model for thrust F.

[0026] The coefficient C in the model E and C s The fitting needs to be performed using ground-based experimental test results of the electro-spray thruster under different acceleration voltages U. The launch current I and thrust F corresponding to different acceleration voltages U are recorded experimentally and compiled into a parallel FU data table. First, using U as the independent variable and I as the dependent variable, based on... The results of fitting the exponential relationship are as follows: Figure 4 As shown, Figure 4 The results of the current-voltage characteristic test and the fitting curve provided in the embodiments of the present invention are shown. Figure 4 In this context, the unit of current is microampere (μA), and the unit of voltage is volt (V). The coefficients obtained through fitting are... , .

[0027] Secondly, based on electrical parameters With F as the independent variable and F as the dependent variable, according to A linear fit was performed, and the results are as follows: Figure 5 As shown, Figure 5 This is the thrust test result and fitting curve provided in the embodiment of the present invention. Figure 5 In this context, the unit of current is ampere (A), the unit of voltage is volt (V), and the unit of thrust is micronewton (μN). The thrust coefficient obtained through fitting is... .

[0028] Depend on Calculations yielded The nonlinear control model of the thrust formula is expressed by the following formula: In step 101, the target thrust value F* is first obtained, which is specifically the thrust value that the electro-spray thruster needs to generate. After determining the target thrust value F*, the acceleration voltage corresponding to the target thrust value F* needs to be calculated based on the calibration data as the initial acceleration voltage U*, which serves as the initial value for the first iteration. In this embodiment of the invention, the calibration relationship is specifically the FU data table. Figure 6 This is a FU data table provided in an embodiment of the present invention. The FU data table is used to characterize the correspondence between acceleration voltage and target thrust value F*. The predicted thrust value is specifically the target thrust value generated by calculation under a certain acceleration voltage. Figure 6 As shown, for each accelerating voltage U i There exists a target thrust value F for each. iCorrespondingly, and, each accelerating voltage U i and target thrust value F i The values ​​monotonically increase with increasing number i. The FU data table is determined through a pre-calibrated experiment.

[0029] In one alternative implementation, the initial acceleration voltage U* corresponding to the target thrust value F* is determined by interpolation. Specifically, for the target thrust value F*, the initial acceleration voltage U* is searched in the FU data table. i and F i+1 This makes F i <F*<F i+1 For example, when the value of F* is 41μN, it can be seen from the table that F4 and F5 satisfy the above conditions.

[0030] After determining F i and F i+1 After the above conditions are met, the value of the initial accelerating voltage U* is determined by the following formula: In the formula, U* is the initial accelerating voltage. Let i be the accelerating voltage. The accelerating voltage is numbered i+1. For the predicted thrust value numbered i, This is the predicted thrust value numbered i+1.

[0031] Although FU is nonlinear, using the linear difference calculation U* based on the FU data table as the initial accelerating voltage is still a simple and quick solution.

[0032] Regarding step 102, after determining the current acceleration voltage, the corresponding launch current I is first determined. Specifically, the launch current I corresponding to the current acceleration voltage U is determined by monitoring. After determining the launch current I, the predicted thrust value F under the current acceleration voltage U is calculated based on a first preset relationship between the predicted thrust value F, the launch current I, and the acceleration voltage U. The first preset relationship is a fitted exponential relationship. Specifically, in this embodiment of the invention, the predicted thrust value calculation formula... In this process, let U be the current acceleration voltage and I be the emission current corresponding to the current acceleration voltage, and we can obtain the predicted thrust value F corresponding to the current acceleration voltage.

[0033] Regarding step 103, after determining the predicted thrust value F, it is determined whether the predicted thrust value F and the target thrust value F* satisfy a second preset relationship. In one optional implementation, the second preset relationship is: ,in, The error threshold can be set manually; for example, it can be set to... Set to 0.05.

[0034] If the predicted thrust value F and the target thrust value F* satisfy a predetermined relationship, it indicates that the difference between the predicted thrust value F and the target thrust value F* is within the allowable range. At this time, it can be considered that the predicted thrust value F corresponding to the current acceleration voltage U meets the requirements of the target thrust value F* within the predetermined error range. Then, proceed to step 104 to end the thrust control.

[0035] If the predicted thrust value F and the target thrust value F* do not satisfy the predetermined relationship, it indicates that the predicted thrust value F and the target thrust value F* differ significantly. In this case, it is necessary to proceed to step 105 to reset the current acceleration voltage and then proceed to step 102 to repeat the above process, so as to recalculate the predicted thrust value F corresponding to the adjusted current acceleration voltage, until the predicted thrust value F and the target thrust value F* satisfy the predetermined relationship. Specifically, since the predicted thrust value F is positively correlated with the acceleration voltage U, if the calculated predicted thrust value F < the target thrust value F*, the current acceleration voltage needs to be increased; conversely, if the calculated predicted thrust value F > the target thrust value F*, the current acceleration voltage needs to be decreased.

[0036] In one alternative implementation, the step size is set. The current acceleration voltage U is adjusted in this way. When the predicted thrust value F < the target thrust value F*, the current acceleration voltage is reset specifically by setting... And repeat steps 102 and 103 to make another judgment; when the predicted thrust value F > the target thrust value F*, reset the current acceleration voltage specifically to let And repeat steps 102 and 103 to perform another judgment, wherein, The value is positive.

[0037] However, if in two consecutive judgments, The sign of the thrust value has changed; that is, the thrust value calculated in two iterations is greater than the target thrust value F* in one iteration and smaller than the target thrust value F* in the other iteration. Furthermore, the predicted thrust value F in both iterations does not satisfy the second preset relationship. Therefore, the thrust value is reduced using a preset method. Specifically, the preset step size at this point. Too long, cannot pass the current The acceleration voltage is adjusted so that the predicted thrust value F corresponding to the current acceleration voltage meets predetermined conditions. At this point, it is necessary to decrease the preset step size. This allows for more precise adjustment of the current accelerating voltage U. In one alternative implementation, it can be made... Reduced to half of the original amount.

[0038] Through steps 101-105, by iteratively determining the accelerating voltage that can generate the target thrust value F*, the acceleration voltage can be determined more accurately.

[0039] This invention calculates the initial acceleration voltage based on the target thrust value F* and calibration data, determines the launch current corresponding to the current acceleration voltage, and calculates the predicted thrust value F under the current voltage based on a first preset relationship between the predicted thrust value, launch current, and acceleration voltage. It then determines whether the difference between the predicted thrust value F and the target thrust value F* satisfies a second preset relationship. If not, the current acceleration voltage is reset and the above calculation and judgment steps are repeated; if satisfied, thrust control ends. This invention achieves control without relying on direct thrust measurement by acquiring electrical parameters in real time and using the known relationship between thrust and electrical parameters for iterative optimization. This solves the thrust control problem caused by the difficulty in accurately monitoring and feeding back the microampere-level operating current of electrospray thrusters in orbit.

[0040] like Figure 2 , Figure 3 As shown, this embodiment of the invention provides an electro-spray thruster control device. The device embodiment can be implemented through software, hardware, or a combination of both. From a hardware perspective, such as... Figure 2 The diagram shown is a hardware architecture diagram of an electronic device for controlling an electro-spray thruster, provided in an embodiment of the present invention. Except for... Figure 2 In addition to the processor, memory, network interface, and non-volatile memory shown, the electronic device in the embodiment may also include other hardware, such as a forwarding chip responsible for processing packets. Taking software implementation as an example, such as... Figure 3 As shown, a device in a logical sense is formed by the CPU of the electronic device in which it is located reading the corresponding computer program from the non-volatile memory into the memory for execution.

[0041] This embodiment provides an electrospray thruster control device, including an initial calculation unit 31, a thrust value calculation unit 32, and a difference judgment unit 33. The initial calculation unit 31 calculates the initial acceleration voltage based on the target thrust value F* and calibration data. The target thrust value F* is the thrust value that the electrospray thruster needs to generate, and the calibration data is a table showing the correspondence between thrust values ​​and acceleration voltages. The thrust value calculation unit 32 determines the emission current corresponding to the current acceleration voltage and calculates the predicted thrust value F under the current acceleration voltage based on a first preset relationship between the predicted thrust value, emission current, and acceleration voltage. The judgment unit 33 judges whether the difference between the predicted thrust value F and the target thrust value F* satisfies a second preset relationship.

[0042] In some embodiments, the first predetermined relationship is: In the formula, F is the predicted thrust value, U is the acceleration voltage, and C is the acceleration voltage. S C is the configuration coefficient. E is the field shape coefficient.

[0043] In some embodiments, the initial acceleration voltage is determined as follows: Based on the calibration data, determine The number i in the FU data table at that time; The initial acceleration voltage is calculated using the following formula: In the formula, U* is the initial accelerating voltage. Let i be the accelerating voltage. The accelerating voltage is numbered i+1. Let i be the target thrust value. The target thrust value is numbered i+1.

[0044] In some embodiments, the second preset relationship is: In the formula, This is the preset error threshold.

[0045] In some embodiments, the current acceleration voltage is reset in the following manner: When F* > F, let ; When F* < F, let ; In the formula, The current accelerating voltage, For the previous round of acceleration voltage, For a preset step size, during two consecutive iterations, if If the sign of F changes and F does not satisfy the second preset relationship in either of the two iterations, then the value is reduced by the preset method. .

[0046] It is understood that the structures illustrated in the embodiments of the present invention do not constitute a specific limitation on an electro-spray thruster control device. In other embodiments of the present invention, an electro-spray thruster control device may include more or fewer components than illustrated, or combine some components, or split some components, or have different component arrangements. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

[0047] The information interaction and execution process between the modules in the above-mentioned device are based on the same concept as the method embodiment of the present invention, and the specific details can be found in the description of the method embodiment of the present invention, and will not be repeated here.

[0048] This invention also provides an electronic device, including a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, it implements an electro-spray thruster control method according to any embodiment of this invention.

[0049] This invention also provides a computer-readable storage medium storing a computer program. When executed by a processor, the computer program causes the processor to perform an electro-spray thruster control method according to any embodiment of this invention.

[0050] Specifically, a system or apparatus equipped with a storage medium may be provided, on which software program code implementing the functions of any of the embodiments described above is stored, and the computer (or CPU or MPU) of the system or apparatus may read and execute the program code stored in the storage medium.

[0051] In this case, the program code read from the storage medium can itself implement the function of any of the above embodiments, and therefore the program code and the storage medium storing the program code constitute part of the present invention.

[0052] Storage media embodiments for providing program code include floppy disks, hard disks, magneto-optical disks, optical disks (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), magnetic tapes, non-volatile memory cards, and ROMs. Alternatively, program code can be downloaded from a server computer via a communication network.

[0053] Furthermore, it should be clear that not only can the program code read by the computer be executed, but also the operating system or other components operating on the computer can be instructed based on the program code to perform some or all of the actual operations, thereby realizing the function of any of the embodiments described above.

[0054] Furthermore, it is understood that the program code read from the storage medium is written to the memory set in the expansion board inserted into the computer or to the memory set in the expansion module connected to the computer. Then, based on the instructions of the program code, the CPU or other components installed on the expansion board or expansion module execute some and all of the actual operations, thereby realizing the function of any of the above embodiments.

[0055] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or electronic device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or electronic device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or electronic device that includes that element.

[0056] Those skilled in the art will understand that all or part of the steps of the above method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it performs the steps of the above method embodiments. The aforementioned storage medium includes various storage media that can store program code, such as ROM, RAM, magnetic disk, or optical disk.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for controlling an electro-spray thruster, characterized in that, include: Step 101: Calculate the initial acceleration voltage based on the target thrust value F* and the calibration data. The target thrust value F* is the thrust value that the electro-spray thruster needs to generate, and the calibration data is a table showing the correspondence between the thrust value and the acceleration voltage. Step 102: Determine the launch current corresponding to the current acceleration voltage, and calculate the predicted thrust value F under the current acceleration voltage based on the first preset relationship between the predicted thrust value, launch current and acceleration voltage. The first preset relationship is a fitted exponential relationship. Step 103: Determine whether the difference between the predicted thrust value F and the target thrust value F* satisfies the second preset relationship; If not satisfied, the current acceleration voltage is reset, and steps 102 and 103 above are executed again to determine whether the predicted thrust value F corresponding to the current acceleration voltage satisfies the second preset relationship. If the conditions are met, thrust control will end.

2. The method according to claim 1, characterized in that, The first pre-determined relationship is: In the formula, F is the predicted thrust value, U is the acceleration voltage, and C is the acceleration voltage. S C is the configuration coefficient. E is the field shape coefficient.

3. The method according to claim 1, characterized in that, The initial acceleration voltage was determined as follows: Based on the calibration data, determine The number i in the FU data table at that time; The initial acceleration voltage is calculated using the following formula: In the formula, U* is the initial accelerating voltage. Let i be the accelerating voltage. The accelerating voltage is numbered i+1. Let i be the target thrust value. The target thrust value is numbered i+1.

4. The method according to claim 1, characterized in that, The second presupposed relationship is: In the formula, This is the preset error threshold.

5. The method according to claim 1, characterized in that, The current acceleration voltage is reset in the following way: When F* > F, let ; When F* < F, let ; In the formula, The current accelerating voltage, For the previous round of acceleration voltage, For a preset step size, during two consecutive iterations, if If the sign of F changes and F does not satisfy the second preset relationship in either of the two iterations, then the value is reduced by the preset method. .

6. An electro-spray thruster control device, characterized in that, include: The initial calculation unit is used to calculate the initial acceleration voltage based on the target thrust value F* and the calibration data. The target thrust value F* is the thrust value that the electro-spray thruster needs to generate, and the calibration data is a table showing the correspondence between the thrust value and the acceleration voltage. The thrust calculation unit is used to determine the emission current corresponding to the current acceleration voltage, and to calculate the predicted thrust value F under the current acceleration voltage based on the first preset relationship between the predicted thrust value, the emission current and the acceleration voltage. The first preset relationship is a fitted exponential relationship. The judgment unit is used to determine whether the difference between the predicted thrust value F and the target thrust value F* satisfies the second preset relationship; If not satisfied, the current acceleration voltage is reset, and the thrust value calculation unit and the judgment unit re-determine whether the predicted thrust value F corresponding to the current acceleration voltage satisfies the second preset relationship. If the conditions are met, thrust control will end.

7. The apparatus according to claim 6, characterized in that, The first pre-determined relationship is: In the formula, F is the predicted thrust value, U is the acceleration voltage, and C is the acceleration voltage. S C is the configuration coefficient. E is the field shape coefficient.

8. The apparatus according to claim 6, characterized in that, The initial acceleration voltage was determined as follows: Based on the calibration data, determine The number i in the FU data table at that time; The initial acceleration voltage is calculated using the following formula: In the formula, U* is the initial accelerating voltage. Let i be the accelerating voltage. The accelerating voltage is numbered i+1. Let i be the target thrust value. The target thrust value is numbered i+1.

9. The apparatus according to claim 6, characterized in that, The second presupposed relationship is: In the formula, This is the preset error threshold.

10. The apparatus according to claim 6, characterized in that, The current acceleration voltage is reset in the following way: When F* > F, let ; When F* < F, let ; In the formula, The current accelerating voltage, For the previous round of acceleration voltage, For a preset step size, during two consecutive iterations, if If the sign of F changes and F does not satisfy the second preset relationship in either of the two iterations, then the value is reduced by the preset method. .

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