Performance optimization and control method of a wide-range continuously variable thrust ion thruster

Abstract

The present application discloses a performance optimization and control method for a wide-range continuously variable thrust ion thruster, which belongs to the field of aerospace propulsion technology. The performance optimization and control method of the present application includes step 1: within the thrust range of normal performance operation of the wide-range continuously variable thrust ion thruster, according to the satellite's on-orbit application requirements and working strategy, dividing the thrust intervals with different levels of requirements; step 2: determining the air supply flow rate of the corresponding thrust working point in each thrust interval; step 3: determining the power supply parameter value under the air supply flow condition of each thrust working point in each thrust interval. The present application realizes the working mode and performance state required by the satellite through a differentiated solution, which can greatly reduce the technical complexity of the wide-range continuously variable thrust ion electric propulsion system. While ensuring that the structural state of the thruster does not change at all, the different types of mission requirements of low-Earth orbit satellites can be met by adjusting and optimizing individual working parameters.

Description

Technical Field

[0001] The present application relates to the field of aerospace propulsion technology, and in particular to a performance optimization and control method for a wide-range continuously variable thrust ion thruster. Background Art

[0002] Currently, domestic and international researchers have primarily focused on optimizing the performance of single-mode or multi-mode ion thrusters, with relatively little research on ion thrusters with wide-range continuously variable thrust modes. This is because the performance adjustment of a wide-range continuously variable thrust ion thruster involves multiple operating parameters, including discharge current, magnetic induction intensity, and anode gas supply. While these parameters can be adjusted for the same thrust operating point through various combinations and matching, the varying weights of these parameters on performance lead to significant differences in discharge voltage, discharge damage, operating efficiency, and power consumption at the same thrust operating point. Clearly, improper design optimization methods for a wide-range continuously variable thrust ion thruster will significantly complicate the development of the entire electric propulsion system, potentially rendering it impossible to implement properly.

[0003] Furthermore, different mission types require different performance requirements for wide-range continuously variable thrust ion thrusters. Some missions require a wide adjustment range, others require high adjustment precision, and still others require the ability to implement emergency flight orbit control. Therefore, ensuring the smooth execution of a satellite's scheduled engineering mission while maintaining good adaptability to space missions is a key research topic for wide-range continuously variable thrust ion thrusters. Therefore, ensuring that the ion thruster maintains optimal performance within the onboard mission range while maximizing the performance of other thruster ranges is also a critical issue.

[0004] Therefore, in response to the application requirements of low-orbit satellites of different mission types, conducting performance optimization research on wide-range continuously variable thrust ion thrusters is one of the key technologies that must be overcome for their on-orbit engineering applications, and it is also a problem that must be solved during the integrated manufacturing process of variable thrust ion electric propulsion systems. Summary of the Invention

[0005] The present invention discloses a performance optimization and control method for a wide-range continuously variable thrust ion thruster, which solves the technical difficulty of optimizing the multi-parameter matching of a variable thrust ion thruster, expands the functional mode and application strategy of the wide-range continuously variable thrust ion thruster on low-orbit satellites, and can effectively promote the engineering application of the variable thrust ion thruster.

[0006] In order to achieve the above object, the present invention discloses a performance optimization method for a wide range continuously variable thrust ion thruster, which is characterized by:

[0007] Step 1: Within the thrust range of the wide-range continuously variable thrust ion thruster for normal operation, divide the thrust ranges into different levels according to the satellite's on-orbit application requirements and working strategies;

[0008] Step 2: determining the air supply flow rate of the corresponding thrust operating point in each thrust range to form an air supply flow rate combination in the thrust range;

[0009] Step 3: determining power supply parameter values ​​under the air supply flow condition at each thrust operating point in each thrust range, the power supply parameter values ​​including discharge current and magnetic induction intensity;

[0010] Step 4: Control the operation of the ion thruster according to the gas supply flow rate and the power supply parameter value.

[0011] According to a preferred embodiment, the thrust ranges for different levels of requirements are specifically:

[0012] Step 11: Within the thrust range within which the continuously variable thrust ion thruster can operate normally, and in accordance with the satellite's scheduled on-orbit application requirements and operating strategy, determine a first performance operating range, wherein the difference between the thrust integer operating points achieved by the anode first gas supply flow rate within the first performance operating range does not exceed 2 mN, and each thrust integer operating point matches the optimal first discharge current and first magnetic induction intensity;

[0013] Step 12: Within the thrust range within which the continuously variable thrust ion thruster can operate normally, the thrust output range of the thruster except the first performance operating range is the second performance operating range. The difference between the thrust integer operating points achieved by the anode second gas supply flow rate within the second performance operating range does not exceed 3 mN. The second discharge current at the thrust integer operating point of each anode under the second gas supply flow rate is the same. The adjustment of different thrust integer operating points under the second gas supply flow rate and second discharge current of each anode is achieved by adjusting the second magnetic induction intensity.

[0014] According to a preferred embodiment, the step 2 is specifically as follows:

[0015] Step 21: Within the first performance operating range, starting from the maximum integer thrust operating point within the first performance operating range, a certain number of integer thrust operating points within the first performance operating range are extracted with a maximum adjustment step of 2 mN, and the first anode gas supply flow rate is determined for each extracted integer thrust operating point in combination with the specific impulse requirement;

[0016] Step 22: Within the second performance operating range, starting from the maximum integer thrust operating point within the second performance operating range, with a maximum adjustment step of 3 mN, extract a certain number of integer thrust operating points within the second performance operating range, and determine the specific impulse requirements of each extracted integer thrust operating point in combination with the propellant storage status of the electric propulsion system storage and supply unit, and clarify the second air supply flow rate of the anode for each extracted integer thrust operating point.

[0017] According to a preferred embodiment, step 3 is specifically as follows:

[0018] Step 31: In the first performance operating range,

[0019] First, determine the first maximum magnetic induction intensity and the first minimum discharge current. Specifically, starting from the maximum anode first gas flow rate within the first performance operating range, gradually increase the first magnetic induction intensity, using the ion beam current corresponding to the thrust of the first gas flow rate as a benchmark. During this process, adjust the first discharge current to ensure ion beam current stability. During parameter adjustment, pay attention to discharge voltage oscillation, requiring the first discharge voltage oscillation to not exceed 20V. The first magnetic induction intensity and the first discharge current when the first discharge voltage oscillation reaches 20V are the first maximum magnetic induction intensity and the first minimum discharge current.

[0020] Secondly, the variation pattern of the first discharge voltage under different first discharge currents is clarified. Specifically, starting from the first minimum discharge current value, the first discharge current is gradually increased. During this process, the first magnetic induction intensity is adjusted to ensure the stability of the ion beam current. During the parameter adjustment process, attention is paid to the first discharge voltage and its oscillation. The first discharge voltage is required to not exceed 38V and the voltage oscillation is required to not exceed 20V. When the first discharge voltage exceeds 38V or the voltage oscillation exceeds 20V, the adjustment process of the first discharge current and the first magnetic induction intensity for this beam state is terminated.

[0021] Finally, a first optimal discharge current and a first optimal magnetic induction intensity are determined. Specifically, the first optimal discharge current and the first optimal magnetic induction intensity are determined by analyzing the discharge loss and the variation of the first discharge voltage with the first magnetic induction intensity during the adjustment process of the first discharge current. At this time, the thruster discharge loss at the beam point is minimized, and the anode voltage and its oscillation are minimized. The first discharge current and the first magnetic induction intensity are the optimal parameter combination for the thrust operating point corresponding to the ion beam under a given anode gas supply.

[0022] Step 32: Within the first performance operating range, maintain the first gas supply flow rate of the anode unchanged, reduce the thrust operating point by 1 mN, and use the corresponding ion beam flow as a reference to determine the optimal parameter combination of the thrust operating point corresponding to the current ion beam flow under the given first gas supply flow rate of the anode using the method of step 31.

[0023] Step 33: Repeat step 32 until the combined optimization of the first discharge current and the first magnetic induction intensity optimal parameters of all thrust integer operating points under the first gas supply flow rate of the current anode is completed.

[0024] Step 34: Repeat step 31, step 32 and step 33 to carry out combined optimization of the first discharge current and the first magnetic induction intensity optimal parameters of the next group of thrust integer operating points under the first air supply flow parameters within the first performance operating range, until the combination of the first discharge current and the first magnetic induction intensity optimal parameters of all thrust integer operating points within the first performance operating range is completed.

[0025] Step 35: Repeat step 31 within the second performance operating range to determine the optimal parameter combination of the second discharge current and the second magnetic induction intensity under the ion beam flow with the thrust corresponding to the maximum anode second gas flow rate within the second performance operating range.

[0026] Step 36: Within the second performance operating range, maintain the second gas supply flow rate and the second discharge current of the anode unchanged, reduce the second magnetic induction intensity, and when the thrust operating point corresponding to the ion beam current decreases by 1 mN, the magnetic induction intensity becomes the second magnetic induction intensity value of the next thrust integer operating point. The second magnetic induction intensity and the second discharge current are the parameter combination of the thrust operating point corresponding to the ion beam current under the given second gas supply flow rate of the anode.

[0027] Step 37: Repeat step 36 until the combination of the second discharge current and the second magnetic induction intensity parameters of all thrust integer operating points under the second gas supply flow rate of the current anode is completed.

[0028] Step 38: Repeat step 35, step 36 and step 37 to carry out combined optimization of the second discharge current and the second magnetic induction intensity parameters of the thrust integer operating points of the next group of anodes under the second air supply flow parameters in the second performance operating range, until the combination of the second discharge current and the second magnetic induction intensity parameters of all thrust integer operating points in the second performance operating range is completed.

[0029] According to a preferred embodiment, the anode third gas flow rate and third discharge current for non-integer thrust operating points between the first performance operating range and the second performance operating range, as well as for non-integer thrust operating points within each range, are generally adjusted based on the principle of selecting the largest value. Specifically, the anode gas flow rate and discharge current corresponding to the integer thrust operating point that is larger than the non-integer thrust operating point and has the smallest difference are selected. Based on this, the third magnetic induction intensity is adjusted until the ion beam current reaches the corresponding thrust value.

[0030] According to a preferred embodiment, the gas supply flow rates of the cathode and the neutralizer are generally determined according to the principles of life and reliability, and a constant gas supply mode is adopted in a wide range continuously variable thrust ion thruster.

[0031] According to a preferred embodiment, the method comprises the following steps:

[0032] Step S1: using a performance optimization method to obtain the anode gas supply flow, the discharge current, and the magnetic induction intensity values ​​at each thrust integer operating point;

[0033] Step S2: determining the working thrust point output by the ion thruster required by the satellite orbit mission;

[0034] Step S3: When the required output working thrust is greater than the current actual working thrust, the gas supply flow rate of the anode is first adjusted, and after the gas supply is balanced, the discharge current and the magnetic induction intensity value determined at the thrust point are adjusted in sequence, and then the magnetic induction intensity is fine-tuned according to the actual ion beam flow so that the ion beam flow value meets the ion beam flow range corresponding to the required output working thrust; when the required output working thrust is smaller than the current actual working thrust, the magnetic induction intensity and the discharge current value determined at the thrust point are adjusted in sequence, and then the gas supply flow rate of the anode is adjusted, and after the gas supply is balanced, the magnetic induction intensity is fine-tuned according to the ion beam flow so that the ion beam flow value meets the ion beam flow range corresponding to the required output working thrust; when the required output working thrust is consistent with the current actual working thrust, no adjustment is required.

[0035] The present invention provides a performance optimization and control method for a wide-range continuously variable thrust ion thruster, which has the following beneficial effects:

[0036] 1. This application utilizes the weak coupling and relative independence between ion extraction and plasma discharge in an ion thruster, aiming to meet the performance requirements of wide-range continuously variable thrust ion thrusters for low-Earth orbit satellites of different mission types. The application classifies the output thrust range of the wide-range continuously variable thrust ion thruster into different stages and optimizes the gas flow rate and power supply parameters at the thrust operating point in each thrust range according to different requirements. While ensuring that the thruster structure remains unchanged, the different mission requirements of low-Earth orbit satellites can be met by adjusting and optimizing individual operating parameters. This technical solution, which uses differentiated solutions to achieve the required operating mode and performance state of the satellite, effectively expands the application scope of wide-range continuously variable thrust ion electric propulsion products and provides support for promoting the engineering application of wide-range continuously variable thrust ion thrusters.

[0037] 2. This application can meet the application requirements of flight missions such as the drag-free flight mission of gravity gradient measurement satellites, and the precise orbit maintenance and accurate attitude control of a series of low-Earth orbit observation satellites. Utilizing the method of this application, the technical complexity of the wide-range continuously variable thrust ion electric propulsion system can be significantly reduced. While ensuring that the structural state of the thruster remains completely unchanged, the adjustment and optimization of individual operating parameters can meet the different types of mission requirements of low-Earth orbit satellites, thereby effectively expanding the scope of application of wide-range continuously variable thrust ion electric propulsion products and providing support for promoting the engineering application of wide-range continuously variable thrust ion thrusters. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The drawings that constitute part of this application are used to provide a further understanding of this application and make other features, objects and advantages of this application more apparent. The illustrative embodiment drawings and their descriptions of this application are used to explain this application and do not constitute an improper limitation of this application. In the drawings:

[0039] Figure 1 is a schematic diagram of a performance optimization method for a wide-range continuously variable thrust ion thruster provided by the present application;

[0040] Figure 2 is a schematic diagram of a control method for a wide-range continuously variable thrust ion thruster provided by the present application;

[0041] Figure 3 This is a detailed process diagram of the control method of the wide-range continuously variable thrust ion thruster provided by the present application;

[0042] Figure 4 This is a parameter list for the wide-range continuously variable thrust ion thruster performance optimization and control method provided in this application. DETAILED DESCRIPTION

[0043] The following is a detailed description with reference to the accompanying drawings. Example

[0044] According to a preferred embodiment, Figure 1 The present application discloses a method for optimizing the performance of a wide-range continuously variable thrust ion thruster. The method specifically comprises the following steps: Step 1: dividing thrust intervals of different levels within the thrust range within which the wide-range continuously variable thrust ion thruster operates normally, according to the satellite's on-orbit application requirements and operating strategies; Step 2: determining the air supply flow rate for a corresponding thrust operating point within each thrust interval to form an air supply flow rate combination within the thrust interval; wherein the air supply flow rate includes a first air supply flow rate, a second air supply flow rate, and a third air supply flow rate; Step 3: determining power supply parameter values ​​under air supply flow conditions at each thrust operating point in each thrust interval; the power supply parameter values ​​include discharge current and magnetic induction intensity; wherein the discharge current includes a first discharge current, a second discharge current, and a third discharge current; and the magnetic induction intensity includes a first magnetic induction intensity, a second magnetic induction intensity, and a third magnetic induction intensity; the air supply flow rate and the corresponding power supply parameter values ​​are combined to form a performance state of a thrust operating point; and Step 4: controlling the operation of the ion thruster based on the air supply flow rate and the power supply parameter values.

[0045] According to a preferred embodiment, the thrust ranges required for different levels are specifically divided as follows: Step 11: Within the thrust range within which the continuously variable thrust ion thruster can operate normally, a first performance operating range is determined in accordance with the satellite's scheduled on-orbit application requirements and operating strategy. The thrust integer operating points achieved by the anode first gas supply flow rate within the first performance operating range differ by no more than 2 mN. Each thrust integer operating point is matched with a separate, optimal first discharge current and first magnetic induction intensity. The first performance operating range is the best performance operating range and is the operating range that must be first guaranteed when optimizing thruster performance.

[0046] Step 12: Within the thrust range within which the continuously variable thrust ion thruster can operate normally, the thrust output range of the thruster except the first performance operating range is the second performance operating range. The difference between the thrust integer operating points achieved by the anode second gas supply flow rate in the second performance operating range does not exceed 3 mN. The second discharge current at the thrust integer operating point under the second anode gas supply flow rate is the same for each anode. The second magnetic induction intensity is adjusted to achieve different thrust integer operating points under the second gas supply flow rate and second discharge current of each anode. The second performance operating range is the suboptimal performance operating range and is the secondary guarantee operating range when optimizing thruster performance.

[0047] According to a preferred embodiment, step 2 is specifically as follows: step 21, within the first performance working range, starting from the maximum integer thrust working point within the first performance working range, with a maximum adjustment step of 2mN, extract a certain number of integer thrust working points within the first performance working range, and determine the anode first air supply flow rate of each extracted integer thrust working point in combination with the specific impulse requirement; step 22, within the second performance working range, starting from the maximum integer thrust working point within the second performance working range, with a maximum adjustment step of 3mN, extract a certain number of integer thrust working points within the second performance working range, and determine the specific impulse requirement of each extracted integer thrust working point in combination with the propellant storage state of the electric propulsion system storage and supply unit, and clarify the anode second air supply flow rate of each extracted integer thrust working point.

[0048] According to a preferred embodiment, step 3 is specifically as follows: Step 31, within the first performance operating range, first determine the first maximum magnetic induction intensity and the first minimum discharge current. Specifically, starting from the maximum anode first gas flow rate within the first performance operating range, and taking the ion beam current corresponding to the thrust of the first gas flow rate as a reference, gradually increase the first magnetic induction intensity (achieved by increasing the excitation current, the same below, and vice versa). During this process, adjust the first discharge current to ensure the stability of the ion beam current. During the adjustment of the above parameters, pay attention to the discharge voltage oscillation, requiring the first discharge voltage oscillation to not exceed 20V. The first magnetic induction intensity and the first discharge current when the first discharge voltage oscillation reaches 20V are the first maximum magnetic induction intensity and the first minimum discharge current.

[0049] Secondly, the variation pattern of the first discharge voltage under different first discharge currents is clarified. Specifically, starting from the first minimum discharge current value, the first discharge current is gradually increased. During this process, the first magnetic induction intensity is adjusted to ensure the stability of the ion beam current. During the adjustment of the above parameters, attention is paid to the first discharge voltage and its oscillation. It is required that the first discharge voltage does not exceed 38V and the voltage oscillation does not exceed 20V. When the first discharge voltage exceeds 38V or the voltage oscillation exceeds 20V, the adjustment process of the first discharge current and the first magnetic induction intensity in this beam state ends;

[0050] Finally, the first optimal discharge current and the first optimal magnetic induction intensity are determined. Specifically, the discharge loss and the first discharge voltage changing with the first magnetic induction intensity during the first discharge current regulation process are analyzed to determine the first optimal discharge current and the first magnetic induction intensity. At this time, the thruster discharge loss at this beam point is the lowest, and the anode voltage and its oscillation are the smallest. The first discharge current and the first magnetic induction intensity are the optimal parameter combination for the thrust operating point corresponding to the ion beam under a given anode gas supply.

[0051] Step 32: Within the first performance operating range, maintain the anode first gas flow rate unchanged, reduce the thrust operating point by 1 mN, and use the corresponding ion beam flow as a benchmark. Use the method of step 31 to determine the optimal parameter combination for the thrust operating point corresponding to the current ion beam flow at the given anode first gas flow rate.

[0052] Step 33: Repeat step 32 until the combined optimization of the optimal parameters of the first discharge current and the first magnetic induction intensity for all thrust integer operating points under the current first anode gas supply flow rate is completed.

[0053] Step 34: Repeat steps 31, 32, and 33 to carry out combined optimization of the optimal parameters of the first discharge current and the first magnetic induction intensity for the next set of thrust integer operating points under the first anode air supply flow parameters within the first performance operating range, until the combination of the optimal parameters of the first discharge current and the first magnetic induction intensity for all thrust integer operating points within the first performance operating range is completed.

[0054] Step 35: Repeat step 31 in the second performance operating range to determine the optimal parameter combination of the second discharge current and the second magnetic induction intensity under the ion beam flow with the thrust corresponding to the maximum anode second gas supply flow in the second performance operating range.

[0055] Step 36: Within the second performance operating range, maintain the anode second gas supply flow rate and the second discharge current unchanged, reduce the second magnetic induction intensity, and when the thrust operating point corresponding to the ion beam current decreases by 1 mN, the magnetic induction intensity becomes the second magnetic induction intensity value of the next thrust integer operating point. The second magnetic induction intensity and the second discharge current are the parameter combination of the thrust operating point corresponding to the ion beam current under the given anode second gas supply flow rate.

[0056] Step 37: Repeat step 36 until the combination of the second discharge current and the second magnetic induction intensity parameters of all thrust integer operating points under the current anode second gas supply flow rate is completed.

[0057] Step 38: Repeat steps 35, 36, and 37 to carry out combined optimization of the second discharge current and the second magnetic induction intensity parameters of the thrust integer operating point under the next set of anode second air supply flow parameters in the second performance operating range, until the combination of the second discharge current and the second magnetic induction intensity parameters of all thrust integer operating points in the second performance operating range is completed.

[0058] According to a preferred embodiment, the anode third gas flow rate and third discharge current are generally adjusted based on the principle of selecting the largest value for the non-integer thrust operating points between the first and second performance operating ranges, as well as for the non-integer thrust operating points within each range. Specifically, the anode gas flow rate and discharge current corresponding to the integer thrust operating point that is larger than the non-integer thrust operating point and has the smallest difference are selected. Based on this, the third magnetic induction intensity is adjusted until the ion beam current reaches the corresponding thrust value.

[0059] According to a preferred embodiment, the gas supply flow rates of the cathode and neutralizer are generally determined according to the principles of life and reliability, and a constant gas supply mode is adopted in a wide range continuously variable thrust ion thruster. Example

[0060] like Figure 2 The figure shows a schematic diagram of a preferred method for controlling a wide-range variable thrust of an ion thruster provided by the present application. According to a preferred embodiment, the present application provides a method for controlling a wide-range variable thrust of an ion thruster, comprising the following steps:

[0061] Step S1: using the optimization method obtained above to obtain the anode gas flow rate, discharge current and magnetic induction intensity values ​​at each thrust integer operating point;

[0062] Step S2: determining the working thrust point output by the ion thruster required by the satellite orbit mission;

[0063] Step S3: When the required output working thrust is greater than the current actual working thrust, the anode gas supply flow rate is first adjusted, and after the gas supply is balanced, the discharge current and magnetic induction intensity values ​​determined at the thrust point are adjusted in sequence, and then the magnetic induction intensity is fine-tuned according to the actual ion beam current so that the ion beam flow rate value meets the ion beam current range corresponding to the required output working thrust; when the required output working thrust is smaller than the current actual working thrust, the magnetic induction intensity and discharge current values ​​determined at the thrust point are first adjusted in sequence, and then the anode gas supply flow rate is adjusted, and after the gas supply is balanced, the magnetic induction intensity is fine-tuned according to the ion beam current so that the ion beam flow rate value meets the ion beam current range corresponding to the required output working thrust; when the required output working thrust is consistent with the current actual working thrust, no adjustment is required.

[0064] Whether to increase or decrease the anode gas supply depends on the required thrust and actual thrust. When the required thrust is greater than the actual thrust, the anode gas supply needs to be increased; when the required thrust is less than the actual thrust, the anode gas supply needs to be decreased. The specific value of the anode gas supply after increasing or decreasing is based on the anode gas supply corresponding to the required thrust.

[0065] After adjusting the anode gas supply, there is a waiting period. During this waiting period, except for the changes in the anode gas supply as it gradually approaches equilibrium, the discharge current and magnetic induction intensity remain constant and relatively stable. During this process, the only thing that changes with the anode gas supply adjustment is the ion beam current. Under normal circumstances, the ion beam current will increase after increasing the anode gas supply, and will decrease after reducing the anode gas supply. Therefore, the criteria for judging the balance of the anode gas supply are:

[0066] Increase the anode gas supply - the ion beam current increases and eventually stabilizes and no longer increases. At this time, it is determined that the increased anode gas supply is in a balanced state.

[0067] Reduce the anode gas supply - the ion beam current decreases and eventually stabilizes and no longer decreases. At this time, it is determined that the reduced anode gas supply is in equilibrium.

[0068] Among them, the discharge current and magnetic induction intensity are adjusted in sequence to the specified values ​​among the specified values, that is, the discharge current and magnetic induction intensity corresponding to the required thrust point. The discharge current and magnetic induction intensity of different thrust points are different. The method for determining the discharge current and magnetic induction intensity of each thrust point is the content described in step 3 of this application.

[0069] Whether the ion beam flow meets the value corresponding to the required thrust, that is, each thrust point corresponds to a unique ion beam flow value, and the ion beam flow values ​​at different thrust points are different. Example

[0070] like Figure 3 The figure shows another preferred method for controlling ion thrusters with a wide range of variable thrust provided by the present application. According to a preferred embodiment, the present application provides a method for controlling ion thrusters with a wide range of variable thrust, comprising the following steps:

[0071] Step S1: using the optimization method obtained above to obtain the anode gas flow rate, discharge current and magnetic induction intensity values ​​at each thrust integer operating point;

[0072] Step S2: determining the working thrust point output by the ion thruster required by the satellite orbit mission;

[0073] When the required output working thrust is greater than the current actual working thrust, first adjust the anode gas flow rate, and then determine whether the gas supply is balanced. If the gas supply is balanced, adjust the discharge current and magnetic induction intensity in sequence to the values ​​corresponding to the required thrust. If the gas supply is unbalanced, wait until the gas supply is balanced, and then adjust the discharge current and magnetic induction intensity in sequence to the values ​​corresponding to the required thrust. Then, fine-tune the magnetic induction intensity according to the actual situation of the ion beam flow to determine whether the ion beam flow meets the value corresponding to the required thrust. If it meets, control the ion thruster to work under the current electrical parameters. If it does not meet, fine-tune the magnetic induction intensity until it meets. When the required output working thrust is greater than the current actual working thrust, first adjust the anode gas flow rate, and then determine whether the anode gas supply is balanced. If it does not meet, fine-tune the magnetic induction intensity until it meets. When the thrust is smaller than the current actual working thrust, first adjust the magnetic induction intensity and discharge current values ​​determined at the thrust point in sequence to the values ​​corresponding to the required thrust, then adjust the anode gas flow rate to determine whether the gas supply is balanced. If it is not balanced, wait until the gas supply is balanced. After the gas supply is balanced, determine whether the ion beam current meets the value corresponding to the required thrust. If it does not meet the requirements, fine-tune the magnetic induction intensity according to the ion beam current until it meets the requirements, and then control the ion thruster to operate under the current electrical parameters. When the required output working thrust is consistent with the current actual working thrust, no adjustment is required. The electrical parameters include gas supply flow rate, magnetic induction intensity, and discharge current.

[0074] Whether to increase or decrease the anode gas supply depends on the required thrust and actual thrust. When the required thrust is greater than the actual thrust, the anode gas supply needs to be increased; when the required thrust is less than the actual thrust, the anode gas supply needs to be decreased. The specific value of the anode gas supply after increasing or decreasing is based on the anode gas supply corresponding to the required thrust.

[0075] After adjusting the anode gas supply, there is a waiting period. During this waiting period, except for the changes in the anode gas supply as it gradually approaches equilibrium, the discharge current and magnetic induction intensity remain constant and relatively stable. During this process, the only thing that changes with the anode gas supply adjustment is the ion beam current. Under normal circumstances, the ion beam current will increase after increasing the anode gas supply, and will decrease after reducing the anode gas supply. Therefore, the criteria for judging the balance of the anode gas supply are:

[0076] Increase the anode gas supply - the ion beam current increases and eventually stabilizes and no longer increases. At this time, it is determined that the increased anode gas supply is in a balanced state.

[0077] Reduce the anode gas supply - the ion beam current decreases and eventually stabilizes and no longer decreases. At this time, it is determined that the reduced anode gas supply is in equilibrium.

[0078] Among them, the discharge current and magnetic induction intensity are adjusted in sequence to the specified values ​​among the specified values, that is, the discharge current and magnetic induction intensity corresponding to the required thrust point. The discharge current and magnetic induction intensity of different thrust points are different. The method for determining the discharge current and magnetic induction intensity of each thrust point is the content described in step 3 of this application.

[0079] Whether the ion beam flow meets the value corresponding to the required thrust, that is, each thrust point corresponds to a unique ion beam flow value, and the ion beam flow values ​​at different thrust points are different.

[0080] like Figure 4 This is a list of parameters for the wide-range continuously variable thrust ion thruster performance optimization and control method provided in this application. The ion thruster's normal operating thrust range is 1-25 mN. The long-term operating range required for satellite on-orbit applications is generally 15-20 mN, with special mode requirements of 3 mN, 8 mN, and 12 mN.

[0081] The thrust range levels are divided into the first performance working range of 14-21mN, and the second performance working range of 1-13mN and 22-25mN.

[0082] The thrust point gas flow rate is determined. The maximum thrust adjustment step in the first performance working range is 2mN. 14-15mN corresponds to the anode gas flow rate of 0.390mg / s, 16-17mN corresponds to the anode gas flow rate of 0.450mg / s, 18-19mN corresponds to the anode gas flow rate of 0.500mg / s, and 20-21mN corresponds to the anode gas flow rate of 0.570mg / s. The maximum thrust adjustment step in the second performance working range is 3mN, 1-3mN corresponds to the anode gas flow rate of 0. The anode gas supply flow rate is 0.100mg / s, 4-6mN corresponds to the anode gas supply flow rate of 0.150mg / s, 7-8mN corresponds to the anode gas supply flow rate of 0.205mg / s, 9-11mN corresponds to the anode gas supply flow rate of 0.250mg / s, 12-13mN corresponds to the anode gas supply flow rate of 0.335mg / s, 22-23mN corresponds to the anode gas supply flow rate of 0.600mg / s, and 24-25mN corresponds to the anode gas supply flow rate of 0.650mg / s.

[0083] The thrust point power supply parameters are determined under the given anode gas flow rate. The maximum thrust adjustment step in the first performance working range is 1mN, the thrust point is 14mN, corresponding to the anode current of 2.19A and the excitation current of 0.45A, the thrust point is 15mN, corresponding to the anode current of 2.03A and the excitation current of 0.53A, the maximum thrust adjustment step in the second performance working range is 3mN, the thrust point 1-3mN, corresponding to the anode current of 0.100A, the excitation current of 0.095A (1mN), 0.120A (2mN), 0.150A (3mN), the thrust point 4-6mN, corresponding to the anode current of 1.100A, the excitation current of 0.165A (4mN), 0.190A (5mN), 0.210A (6mN), and the data of other thrust points are in Figure 4 Listed in detail.

[0084] It should be noted that the above-mentioned specific embodiments are exemplary, and those skilled in the art can come up with various solutions inspired by the disclosure of the present invention, and these solutions also belong to the disclosure scope of this application and fall within the scope of protection of this application. Those skilled in the art should understand that the present application specification and its drawings are illustrative and do not constitute a limitation on the claims. The scope of protection of this application is defined by the claims and their equivalents. The present application specification contains multiple inventive concepts, such as "preferably", "according to a preferred embodiment" or "optionally", which means that the corresponding paragraph discloses an independent concept, and the applicant reserves the right to file a divisional application based on each inventive concept.

Claims

1. A performance optimization method for a wide range continuously variable thrust ion thruster, characterized by: Step 1: Within the thrust range of the wide-range continuously variable thrust ion thruster for normal operation, divide the thrust ranges into different levels according to the satellite's on-orbit application requirements and working strategies; Step 11: Within the thrust range within which the continuously variable thrust ion thruster can operate normally, and in accordance with the satellite's scheduled on-orbit application requirements and operating strategy, determine a first performance operating range, wherein the difference between the thrust integer operating points achieved by the anode first gas supply flow rate within the first performance operating range does not exceed 2 mN, and each thrust integer operating point matches the optimal first discharge current and first magnetic induction intensity; Step 12: Within the thrust range within which the continuously variable thrust ion thruster can operate normally, the thrust output range of the thruster except the first performance operating range is the second performance operating range. The difference between the thrust integer operating points achieved by the anode second gas supply flow rate within the second performance operating range does not exceed 3 mN. The second discharge current at the thrust integer operating point under the second gas supply flow rate is the same for each anode. The second magnetic induction intensity is adjusted to achieve different thrust integer operating points under the second gas supply flow rate and second discharge current of each anode. Step 2: determining the air supply flow rate of the corresponding thrust operating point in each thrust range to form an air supply flow rate combination in the thrust range; Step 21: Within the first performance operating range, starting from the maximum integer thrust operating point within the first performance operating range, a certain number of integer thrust operating points within the first performance operating range are extracted with a maximum adjustment step of 2 mN, and the first anode gas supply flow rate is determined for each extracted integer thrust operating point in combination with the specific impulse requirement; Step 22: Within the second performance operating range, starting from the maximum integer thrust operating point within the second performance operating range, with a maximum adjustment step of 3 mN, a certain number of integer thrust operating points within the second performance operating range are extracted. The specific impulse requirement of each extracted integer thrust operating point is determined in combination with the propellant storage state of the electric propulsion system storage and supply unit, and the second anode air supply flow rate for each extracted integer thrust operating point is determined. Step 3: determining power supply parameter values ​​under the air supply flow condition at each thrust operating point in each thrust range, the power supply parameter values ​​including discharge current and magnetic induction intensity; Step 4: Control the operation of the ion thruster according to the gas supply flow rate and the power supply parameter value.

2. The performance optimization method of a wide range continuously variable thrust ion thruster according to claim 1, characterized in that: The step 3 is specifically as follows: Step 31: In the first performance operating range, First, a first maximum magnetic induction intensity and a first minimum discharge current are determined, specifically: starting from the maximum anode first gas flow rate within the first performance operating range, the first magnetic induction intensity is gradually increased based on the ion beam current corresponding to the thrust of the first gas flow rate. During this process, the first discharge current is adjusted to ensure the stability of the ion beam current. During the parameter adjustment process, attention is paid to the discharge voltage oscillation, requiring that the first discharge voltage oscillation does not exceed 20V; the first magnetic induction intensity and the first discharge current when the first discharge voltage oscillation reaches 20V are the first maximum magnetic induction intensity and the first minimum discharge current; Secondly, clarifying the variation pattern of the first discharge voltage under different first discharge currents, specifically: starting from the first minimum discharge current value, gradually increasing the first discharge current, adjusting the first magnetic induction intensity during this process to ensure the stability of the ion beam current, paying attention to the first discharge voltage and its oscillation during the parameter adjustment process, requiring the first discharge voltage to not exceed 38V and the voltage oscillation to not exceed 20V; when the first discharge voltage exceeds 38V or the voltage oscillation exceeds 20V, the adjustment process of the first discharge current and the first magnetic induction intensity under this beam state is terminated; Finally, a first optimal discharge current and a first optimal magnetic induction intensity are determined, specifically by analyzing the variation of the discharge loss and the first discharge voltage with the first magnetic induction intensity during the adjustment process of the first discharge current, and determining the first optimal discharge current and the first magnetic induction intensity at which the thruster discharge loss at the beam point is minimized and the anode voltage and its oscillation are minimized. The first discharge current and the first magnetic induction intensity are the optimal parameter combination for the thrust operating point corresponding to the ion beam under a given anode gas supply; Step 32: Within the first performance operating range, maintaining the first gas flow rate at the anode unchanged, reducing the thrust operating point by 1 mN, and using the corresponding ion beam current as a reference, determining the optimal parameter combination for the thrust operating point corresponding to the current ion beam current at the given first gas flow rate at the anode using the method of Step 31; Step 33: repeating step 32 until the combined optimization of the first discharge current and the first magnetic induction intensity optimal parameters for all thrust integer operating points under the first gas supply flow rate of the current anode is completed; Step 34: Repeat Step 31, Step 32, and Step 33 to carry out combined optimization of the first discharge current and the first magnetic induction intensity optimal parameters for the next group of anode thrust integer operating points under the first air supply flow parameter within the first performance operating range, until the combined optimization of the first discharge current and the first magnetic induction intensity optimal parameters for all thrust integer operating points within the first performance operating range is completed; Step 35: Repeat step 31 within the second performance operating range to determine an optimal parameter combination of the second discharge current and the second magnetic induction intensity under the ion beam flow with the thrust corresponding to the maximum anode second gas flow rate within the second performance operating range; Step 36: Within the second performance operating range, maintain the second gas supply flow rate and the second discharge current at the anode unchanged, and reduce the second magnetic induction intensity. When the thrust operating point corresponding to the ion beam current decreases by 1 mN, the magnetic induction intensity becomes the value of the second magnetic induction intensity at the next thrust integer operating point. The second magnetic induction intensity and the second discharge current are the parameter combination corresponding to the thrust operating point of the ion beam current at the given second gas supply flow rate at the anode. Step 37: Repeat step 36 until the combination of the second discharge current and the second magnetic induction intensity parameters of all thrust integer operating points under the second gas supply flow rate of the current anode is completed; Step 38: Repeat step 35, step 36 and step 37 to carry out combined optimization of the second discharge current and the second magnetic induction intensity parameters of the thrust integer operating points of the next group of anodes under the second air supply flow parameters in the second performance operating range, until the combination of the second discharge current and the second magnetic induction intensity parameters of all thrust integer operating points in the second performance operating range is completed.

3. The performance optimization method of a wide range continuously variable thrust ion thruster according to claim 1, characterized in that: The adjustment settings of the anode third gas supply flow rate and the third discharge current for the non-integer thrust operating points between the first performance operating range and the second performance operating range, as well as the non-integer thrust operating points within each range, generally follow the principle of selecting the largest value, specifically: selecting the anode gas supply flow rate and the discharge current belonging to the integer thrust operating point that is larger than the non-integer thrust operating point and has the smallest difference; on this basis, adjusting the third magnetic induction intensity until the ion beam current reaches the corresponding thrust value.

4. The performance optimization method of a wide range continuously variable thrust ion thruster according to claim 1, characterized in that: The gas supply flow rates of the cathode and neutralizer are generally determined according to the principles of life and reliability, and a constant gas supply mode is adopted in wide range continuously variable thrust ion thrusters.

5. A method for controlling ion thruster with wide range variable thrust, characterized in that: The steps include: Step S1: using the performance optimization method according to any one of claims 1 to 4 to obtain the anode gas supply flow rate, the discharge current, and the magnetic induction intensity values ​​at each thrust integer operating point; Step S2: determining the working thrust point output by the ion thruster required by the satellite orbit mission; Step S3: When the required output working thrust is greater than the current actual working thrust, the gas supply flow rate at the anode is adjusted, and after the gas supply is balanced, the discharge current and the magnetic induction intensity values ​​determined at the thrust point are adjusted in sequence, so that the ion beam flow rate value meets the ion beam flow range corresponding to the required output working thrust according to the actual ion beam flow; when the required output working thrust is smaller than the current actual working thrust, the magnetic induction intensity and the discharge current values ​​determined at the thrust point are adjusted in sequence, and the gas supply flow rate at the anode is adjusted, and after the gas supply is balanced, the magnetic induction intensity is fine-tuned according to the ion beam flow so that the ion beam flow rate value meets the ion beam flow range corresponding to the required output working thrust; when the required output working thrust is consistent with the current actual working thrust, no adjustment is required.

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