Method, device and equipment for identifying working state of alternating voltage electric spray thruster

Abstract

The application provides an alternating voltage electric spray thruster working state recognition method, device and equipment, relates to the electric spray thruster technical field, and comprises the following steps: in the case where the voltage polarity of an alternating voltage electric spray thruster reverses, collecting a corresponding emission current sequence of the alternating voltage electric spray thruster; extracting a target characteristic quantity corresponding to the emission current sequence, the target characteristic quantity being used for describing the characteristics in the process in which the emission current sequence recovers from a disturbance state to a stable state after the voltage polarity reversal event occurs; and identifying the working state of the alternating voltage electric spray thruster according to the target characteristic quantity. The application can only use the emission current data of the thruster, extract a limited number of simple features from the current waveform under the alternating voltage condition, and realize online identification of states such as 'normal working / serious over spray / high and low flow / launching attenuation'.

Description

Technical Field

[0001] This invention relates to the field of electronic fuel injection thruster technology, and in particular to a method, apparatus and equipment for identifying the working state of an alternating voltage electronic fuel injection thruster. Background Technology

[0002] Ionic liquid electrospray thrusters (ILETs) have become an important propulsion solution for micro and nanosatellites due to their high specific impulse, high thrust adjustment precision, and small system size. In recent years, to address the issues of thrust plume neutralization and electrochemical reaction deposition / erosion, an increasing number of ILETs have adopted a high-voltage drive mode with alternating polarity. This allows the emitted beam of the ILET to periodically switch between positive and negative polarities (typically with a switching period of 1 Hz), achieving self-neutralization of the plume and suppressing electrochemical reactions between ionic liquids or between the ionic liquid and the emitter.

[0003] Under alternating voltage drive, the emission current of the electronic fuel injection system is disturbed during voltage polarity switching, exhibiting transient characteristics of "over-injection—valley—recovery" (e.g., Figure 1 The diagram illustrates the emission current of an electro-injector during voltage polarity switching: a large current spike occurs at the moment of polarity reversal. Subsequently, due to over-emission, the liquid supply at the emitter outlet is temporarily insufficient, entering a current trough phase. Finally, within a certain recovery time (the continuous liquid supply compensates for the liquid shortage at the emitter outlet caused by over-emission), the current returns to a new steady-state state. Experiments and numerical simulations show that the current spike during polarity switching leads to a significant increase in the beam divergence angle, which in turn increases the gate intercept current, ultimately resulting in intensified gate sputtering and shortened lifetime.

[0004] In addition to the short-term transient characteristics during voltage polarity switching, during the long-term operation of the electronic fuel injection thruster, the steady-state average current of the ejector will slowly decay due to factors such as electrochemical reactions, unexpected discharges, emitter corrosion and deposition, liquid denaturation, and blockage of the liquid supply channel, resulting in a decline in overall propulsion performance.

[0005] While existing research has revealed phenomena such as current spikes and increased jet divergence in EFI thrusters under alternating voltage, an effective method for monitoring and real-time identification of thruster operating conditions is lacking. Existing thruster diagnostic techniques often rely on operators to roughly assess thruster status by observing abnormal current amplitudes, or on using high-velocity cameras, Faraday probes, RPA probes, and micro-flowmeters to detect parameters such as jet morphology, emission particle divergence angle and composition, and liquid supply flow rate. These methods are either insufficiently precise and lack real-time performance, or require additional complex equipment, increasing thruster mass or being difficult to implement in actual space operations. The lack of timely identification of operating conditions may lead to prolonged operation of the thruster in an unstable state, causing adverse consequences: for example, current overshoot can lead to increased jet divergence, causing grid sputtering and propellant deposition, ultimately shortening thruster lifespan. In summary, there is currently a lack of a method that utilizes only thruster emission current data to extract a limited number of simple features from the current waveform under alternating voltage conditions to achieve online identification of states such as "normal operation / severe overjet / high / low flow rate / emission attenuation." Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a method, device and equipment for identifying the working state of an alternating voltage electronic fuel injection thruster, which can extract a limited number of simple features from the current waveform using only the thruster's emission current data under alternating voltage conditions, and realize online identification of states such as "normal operation / severe over-injection / high or low flow rate / emission attenuation".

[0007] In a first aspect, the present invention provides a method for identifying the operating state of an alternating voltage electronic fuel injection thruster, comprising:

[0008] In the event of a voltage polarity reversal event in an alternating voltage EFI thruster, the corresponding emission current sequence of the alternating voltage EFI thruster is collected;

[0009] The target feature quantity corresponding to the emission current sequence is extracted. The target feature quantity is used to describe the characteristics of the emission current sequence during the process of recovering from the disturbed state to the steady state after the voltage polarity reversal event occurs.

[0010] The operating states of the alternating voltage electronic injection thruster are identified based on the target characteristic quantities. The operating states include normal stable launch state, over-injection state, high / low flow state, and launch attenuation state.

[0011] In one implementation, extracting the target feature quantity corresponding to the emission current sequence includes:

[0012] Determine the judgment threshold corresponding to the emission current sequence;

[0013] Based on the judgment threshold, the first emission current subsequence in the emission current sequence that meets the preset conditions is identified, and the moment corresponding to the first emission current in the emission current subsequence is taken as the stable moment of the emission current.

[0014] Based on the stable moment of the emission current, the occurrence moment of the voltage polarity reversal event, and the predefined half-cycle duration of the voltage waveform, a disturbance time window and a steady-state time window are constructed.

[0015] Feature extraction is performed on the emission current within the disturbance time window and the emission current within the steady-state time window to obtain the target feature quantity.

[0016] In one implementation, the preset condition is that the absolute value of the first-order difference of multiple consecutive transmission currents is less than or equal to a judgment threshold.

[0017] In one implementation, a disturbance time window and a steady-state time window are constructed based on the stable emission current moment, the occurrence moment of the voltage polarity reversal event, and a predefined half-cycle duration of the voltage waveform, including:

[0018] A disturbance time window is constructed, with the occurrence of the voltage polarity reversal event as the starting point and the stabilization of the emission current as the ending point.

[0019] The steady-state time window is constructed by taking the moment when the emission current stabilizes as the starting point and determining the ending point based on the occurrence time of the voltage polarity reversal event and the predefined half-cycle duration of the voltage waveform.

[0020] In one implementation, feature extraction is performed on the emission current within the disturbance time window and the emission current within the steady-state time window to obtain target feature quantities, including:

[0021] The mean value of the emission current within the steady-state time window is used as the steady-state current characteristic; the maximum emission current within the disturbance time window is used as the peak current characteristic; the minimum emission current within the disturbance time window is used as the valley current characteristic; and the mean value of multiple steady-state current characteristics is used as the average steady-state current characteristic.

[0022] The target characteristic quantities are obtained by dimensionlessly processing the steady-state current characteristics, peak current characteristics, valley current characteristics, average steady-state current characteristics, and the time required for the emitted current to recover from the disturbance state to the steady state.

[0023] In one implementation, the steady-state current characteristics, peak current characteristics, valley current characteristics, average steady-state current characteristics, and the time required for the emitted current to recover from a disturbance state to a steady state are processed dimensionlessly to obtain target characteristic quantities, including:

[0024] The ratio between the peak current characteristic and the steady-state current characteristic is used as the peak current ratio characteristic.

[0025] Furthermore, the ratio between the valley current characteristic and the steady-state current characteristic is used as the valley current ratio characteristic;

[0026] In addition, the ratio between the average steady-state current characteristic and the preset emission reference current is used as the current attenuation coefficient characteristic;

[0027] In addition, the ratio between the time required for the emitted current to recover from the disturbance state to the steady state and the predefined half-cycle duration of the voltage waveform is used as a normalized recovery time feature;

[0028] The peak current ratio, valley current ratio, current decay coefficient, and normalized recovery time are used as target feature quantities.

[0029] In one embodiment, identifying the operating state of the alternating voltage electronic fuel injection thruster based on target characteristic quantities includes:

[0030] Based on the characteristics of peak current ratio, valley current ratio, and normalized recovery time, it is possible to identify whether the alternating voltage electronic injection thruster is in a normal and stable launch state.

[0031] Based on the characteristics of peak current ratio and valley current ratio, it is possible to identify whether the alternating voltage electronic injection thruster is in an over-injection state.

[0032] Based on the normalized recovery time characteristics, it is possible to identify whether the alternating voltage electronic injection thruster is in a high / low flow state.

[0033] Based on the characteristics of the current attenuation coefficient, it is possible to identify whether the alternating voltage electronic fuel injection thruster is in a launch attenuation state.

[0034] Secondly, the present invention also provides an alternating voltage electronic injection thruster operating status identification device, comprising:

[0035] The current acquisition module is used to acquire the corresponding launch current sequence of the alternating voltage electronic fuel injection thruster in the event of a voltage polarity reversal event.

[0036] The feature extraction module is used to extract the target feature quantity corresponding to the emission current sequence. The target feature quantity is used to describe the characteristics of the emission current sequence during the process of recovering from the disturbed state to the steady state after the voltage polarity reversal event occurs.

[0037] The status recognition module is used to identify the operating status of the alternating voltage electronic injection thruster based on the target characteristic quantities. The operating status includes normal stable launch status, over-injection status, high / low flow status, and launch attenuation status.

[0038] Thirdly, the present invention also provides an electronic device including a processor and a memory, the memory storing computer-executable instructions executable by the processor, the processor executing the computer-executable instructions to implement any of the methods provided in the first aspect.

[0039] Fourthly, the present invention also provides a computer-readable storage medium storing computer-executable instructions, which, when invoked and executed by a processor, cause the processor to implement any of the methods provided in the first aspect.

[0040] This invention provides a method, apparatus, and device for identifying the operating state of an alternating voltage electronic fuel injection (EFI) thruster. When a voltage polarity reversal event occurs in the EFI thruster, the method acquires the corresponding emission current sequence. Then, it extracts target feature quantities corresponding to the emission current sequence. These target feature quantities describe the characteristics of the emission current sequence during the recovery process from a disturbed state to a stable state after the voltage polarity reversal event. Finally, it identifies the corresponding operating state of the EFI thruster based on the target feature quantities. The operating states include normal stable emission state, over-injection state, high / low flow state, and emission attenuation state. This method can utilize only the thruster emission current data and extract a limited number of simple features from the current waveform under alternating voltage conditions to achieve online identification of states such as "normal operation / severe over-injection / high / low flow / emission attenuation."

[0041] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained in accordance with the structures particularly pointed out in the description, claims and drawings.

[0042] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0043] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0044] Figure 1 A schematic diagram of the voltage polarity switching process of the emission current of an electronic fuel injection system provided in an embodiment of the present invention;

[0045] Figure 2A flowchart illustrating a method for identifying the operating state of an alternating voltage electronic fuel injection thruster according to an embodiment of the present invention;

[0046] Figure 3 A flowchart illustrating another method for identifying the operating state of an alternating voltage electronic fuel injection thruster provided in an embodiment of the present invention;

[0047] Figure 4 This is a schematic diagram of the structure of an alternating voltage electronic fuel injection thruster operating status identification device provided in an embodiment of the present invention;

[0048] Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] Currently, existing technologies struggle to balance recognition accuracy and equipment complexity. Therefore, this invention provides a method, apparatus, and device for identifying the operating status of an alternating voltage electronic fuel injection thruster. This method can extract a limited number of simple features from the current waveform using only the thruster's emission current data under alternating voltage conditions, enabling online identification of states such as "normal operation / severe over-injection / high / low flow rate / emission attenuation".

[0051] To facilitate understanding of this embodiment, a detailed description of the method for identifying the operating state of an alternating voltage electronic fuel injection thruster disclosed in this embodiment of the invention will be provided first. (See [link to relevant documentation]). Figure 2 The flowchart shown is a method for identifying the working state of an alternating voltage electronic fuel injection thruster. The method mainly includes the following steps S202 to S206:

[0052] Step S202: In the event of a voltage polarity reversal event in the alternating voltage electronic fuel injection thruster, the corresponding emission current sequence of the alternating voltage electronic fuel injection thruster is collected.

[0053] Among them, the voltage polarity reversal event, that is, the event in which the voltage value changes from positive to negative or from negative to positive, can be used as the starting time to construct a time window, so as to collect the corresponding launch current sequence of the alternating voltage EJT thruster according to the time window.

[0054] Step S204: Extract the target feature quantities corresponding to the emission current sequence.

[0055] The target feature is used to describe the characteristics of the emitter current sequence during its recovery from a disturbed state to a steady state after a voltage polarity reversal event. The target feature may include one or more of the following: peak current ratio, valley current ratio, current attenuation coefficient, and normalized recovery time. In one example, the first emitter current in the emitter current sequence to recover to a stable state can be identified, and its corresponding time can be used as the current recovery time to construct a disturbance time window and a steady-state time window. Then, based on the emitter current within the two windows, the original feature is extracted. After dimensionless processing of the original feature, the target feature is obtained.

[0056] Step S206: Identify the operating state of the alternating voltage electronic injection thruster based on the target characteristic quantity.

[0057] The operating states include normal stable launch state, over-injection state, high / low flow state, and launch attenuation state. In one example, a mapping relationship between target characteristic quantities and operating states is pre-configured. Then, based on the comparison results between one or more of the following characteristics—current peak ratio, current valley ratio, current attenuation coefficient, and normalized recovery time—and preset thresholds, the current operating state of the alternating voltage EFI thruster is identified.

[0058] The alternating voltage electronic fuel injection thruster operating state identification method provided in this invention relies solely on the time-varying data of the emitter current. By constructing a few dimensionless feature quantities and corresponding criteria, it achieves the following functions:

[0059] (1) Identify overspray state (excessive peak current or deep valley value) near polarity reversal to provide a basis for limiting beam divergence angle and beam-gate collision;

[0060] (2) The dimensionless characteristic quantity of current recovery time is used to indicate the magnitude or trend of propellant flow rate (which can be used for flow rate judgment or estimation).

[0061] (3) Monitor the launch attenuation state (degradation of thruster performance) by the slow change of steady-state current in the platform segment, and trigger compensation or early warning accordingly.

[0062] This method does not rely on additional sensors; it only requires adding a simple data processing module to the existing transmit current measurement circuit, making it suitable for long-term spaceborne use. Under alternating polarity periodic drive, this invention analyzes the voltage waveform in units of each half-cycle.

[0063] For ease of understanding, embodiments of the present invention provide, as follows: Figure 3 The flowchart shown is a different method for identifying the operating status of an alternating voltage electronic fuel injection thruster, including:

[0064] Step 1, Extraction of original features from the current curve. This includes:

[0065] Step 1.1, Polarity reversal moment identification:

[0066] Determine the k-th voltage polarity reversal time using the driving voltage waveform V(t). The half-cycle duration of the voltage waveform is denoted as... .

[0067] Step 1.2, Time Window Division:

[0068] First, a judgment threshold is determined for the corresponding emission current sequence. Then, based on the judgment threshold, the first emission current subsequence within the emission current sequence that meets the preset condition is identified. The moment corresponding to the first emission current in the emission current subsequence is taken as the stable emission current moment. The preset condition is that the absolute value of the first-order difference of multiple consecutive emission currents is less than or equal to the judgment threshold. Finally, based on the stable emission current moment, the occurrence moment of the voltage polarity reversal event, and the predefined half-cycle duration of the voltage waveform, a disturbance time window and a steady-state time window are constructed. This includes: constructing a disturbance time window with the occurrence moment of the voltage polarity reversal event as the starting point and the stable emission current moment as the ending point; and constructing a steady-state time window with the stable emission current moment as the starting point and the termination point determined according to the occurrence moment of the voltage polarity reversal event and the predefined half-cycle duration of the voltage waveform.

[0069] In practical implementation, the emission current is initially disturbed and enters an unsteady state after the voltage polarity switch, before stabilizing. To distinguish between these states, the sampled emission current... I [ n (Sampling time step is) ), calculate the first difference:

[0070]

[0071] In the k The time interval of one and a half cycles Within, take the corresponding difference sequence. To distinguish between the disturbance and steady segments of the current curve, a judgment threshold is automatically determined from the data. .in: yes The p Quantiles are the values ​​of the absolute values ​​of all current changes within a period, sorted from smallest to largest, and the quantiles are taken from the top (i.e., those at the top). p The value at position ×100)% is used as the characteristic value of the rate of change in the current steady range. p 0.5 is acceptable. c This is the noise margin of the steady-state current (which can be taken as 1-3).

[0072] In the k One and a half cycles From Scan backwards to find the first continuous sequence. L Within each sampling point, The corresponding time will be recorded as _____. (Steady start) is the moment when the emission current stabilizes again. Define the window of current instability after polarity reversal: Used to capture overspray peaks and troughs; a new plateau window for current restabilization. This is used to calculate the steady-state current. Additionally, it calculates the time required for the current to return to a steady state after a polarity reversal. .

[0073] In another implementation, in addition to using the current derivative to automatically divide the disturbance interval and the steady-state interval, the peak / valley current and the steady-state plateau can also be selected based on the fixed time ratio of the half-cycle and the time period with the smallest current variance. As long as representative peak current, valley current and steady-state current can be obtained, it is considered an equivalent scheme.

[0074] Step 1.3, Obtaining Original Feature Quantities: The average emission current within the steady-state time window is used as the steady-state current feature; the maximum emission current within the disturbance time window is used as the peak current feature; the minimum emission current within the disturbance time window is used as the valley current feature; and the average of multiple steady-state current features is used as the average steady-state current feature. Specifically:

[0075] In the k Within one and a half cycles, various feature quantities (such as...) are obtained. Figure 1 (as shown)

[0076] steady-state current : ;

[0077] Peak current : ;

[0078] Valley current : ;

[0079] recent M Average steady-state current during one and a half cycles : .

[0080] In this embodiment of the invention, based on the study of the characteristics of the emission current of the electronic injection under alternating voltage, the characteristic quantities of the emission current after the voltage polarity changes are proposed: the peak current, valley current and recovery time are automatically extracted in the disturbance interval, and the steady-state current is extracted in the steady-state interval, providing a unified basis for the subsequent construction of dimensionless characteristic quantities and state recognition.

[0081] Step 2, dimensionless construction: The steady-state current characteristics, peak current characteristics, valley current characteristics, average steady-state current characteristics, and the time required for the emission current to recover from the disturbance state to the steady state are processed in a dimensionless manner to obtain the target characteristic quantities.

[0082] In practical implementation, to facilitate unified judgment under different operating conditions, this invention renders the above features dimensionless, constituting dimensionless characteristic quantities of the current waveform:

[0083] In one example, the ratio between the peak current characteristic and the steady-state current characteristic is used as the current peak ratio characteristic. : ;

[0084] In one example, the ratio between the valley current characteristic and the steady-state current characteristic is used as the valley ratio characteristic. : ;

[0085] In one example, the ratio of the time required for the emitted current to recover from a disturbed state to a steady state to the predefined half-cycle duration of the voltage waveform is used as the normalized recovery time feature. Normalized Recovery Time : The recovery time of the launch current after a disturbance is closely related to the propellant supply condition; a longer recovery time often corresponds to a smaller effective propellant flow rate, and vice versa. Under basically fixed geometric and operating voltage conditions, With propellant effective flow rate Q They are inversely proportional.

[0086] In one example, the ratio between the average steady-state current characteristic and a preset transmit reference current is used as the current attenuation coefficient characteristic. Current attenuation coefficient : ;in, The reference current for transmission can be the average steady-state current under initial operating conditions or the target current required for the mission.

[0087] In another implementation, dimensionless features such as peak ratio, valley ratio, recovery time, and current decay coefficient can be replaced by other equivalent forms, such as current relative deviation and peak / valley area, as long as these features can still reflect the changes in transient intensity, recovery speed, and long-term emission capability of the electronic injection based on the emission current under alternating voltage.

[0088] Step 3, Working Status Identification:

[0089] Step 3.1: Based on the peak current ratio, valley current ratio, and normalized recovery time characteristics, identify whether the alternating voltage EFI thruster is in a normal stable launch (NORMAL) state. Specifically:

[0090] The peak and trough values ​​should be moderate, and the recovery time should be within a reasonable range.

[0091]

[0092]

[0093]

[0094] in and The threshold values ​​are determined based on the thruster structure and life requirements, and are used to limit excessively high peak current (directly related to overspray) and excessively deep valley current (excessive overspray leads to a lack of liquid at the emitter outlet, which in turn leads to a very small valley value of the subsequent emission current, or even 0 for a period of time).

[0095] The above peak ratio upper limit The divergence angle of the electro-injection beam can be determined using a calibration curve of the current versus the emission angle. Previous studies have shown that there is an approximately linear relationship between the divergence angle and the emission current of the electro-injection beam driven by alternating voltage.

[0096] ;

[0097] in, A half-angle containing 95% of the beam current. For instantaneous emission current; and a These are fitting parameters related to the thruster structure and operating voltage. These parameters can be obtained through ground calibration tests, i.e., by measuring the corresponding beam angle distribution under different steady-state emission currents. Based on this relationship, given a given upper limit for the maximum allowable divergence angle, the corresponding maximum allowable peak current can be deduced, which is used to determine the upper limit of the peak-to-peak ratio in the overjet criterion of this invention. :

[0098] ;

[0099] in, This represents the maximum allowable emission current corresponding to the maximum allowable divergence angle.

[0100] For the lower limit of the valley ratio Determination: Existing theoretical and experimental studies have shown that, under steady-state conical jet mode, electro-injection has a minimum steady-state flow rate determined by liquid properties. When the volumetric flow rate falls below this value, the cone jet will become unstable. This minimum flow rate can be expressed as the characteristic flow rate. With dimensionless parameters The function (where) , , K For liquid surface tension, density, and conductivity, The vacuum permittivity, For the dimensionless parameter of viscosity effect, (The dimensionless parameter represents the polarization effect). The relationship between the minimum flow rate and the characteristic flow rate, and the dimensionless parameter, can be approximated as a simple power law; however, the specific parameters need to be experimentally determined. Based on the above, the current scaling relationship of steady-state electronic fuel injection is used... The corresponding minimum steady-state current is obtained by conversion. Therefore, this invention sets the lower limit of the valley ratio as follows:

[0101] .

[0102] Furthermore, normalized recovery time characteristic quantity Used to characterize the effective flow rate of propellant. There is an inverse relationship between this and the propellant flow rate: The larger the emitter current, the longer it takes for it to recover from its trough to a steady state, indicating that the emitter outlet remains in a liquid shortage state for a longer period after overspray, suggesting that the current flow rate is too low; conversely, The smaller the value, the stronger the propellant supply capacity and the larger the flow rate. Therefore, by conducting ground calibration tests and determining the thruster's operating flow rate range, the normal range of the normalized recovery time can be obtained. :when satisfy At that time, the corresponding propellant flow rate is within the allowable normal operating range; when or At that time, it indicates either high flow rate or low flow rate operating conditions.

[0103] Step 3.2: Based on the peak current ratio and valley current ratio characteristics, identify whether the alternating voltage EFI thruster is in an overspray state. Specifically:

[0104] This section identifies excessive transient emissions caused by polarity reversal, relying solely on peak and trough amplitude characteristics as the criterion, which is the opposite of the judgment for normal stable emissions. If the following conditions are met:

[0105]

[0106] If so, it is determined that the current half-cycle is in an overspray state.

[0107] In this embodiment of the invention, a dimensionless characteristic quantity is proposed. Furthermore, it provides overjet detection rules based on the two, which can identify abnormal emission behavior at the moment of polarity reversal simply by using amplitude characteristics, thus forming an overjet detection method specifically for alternating voltage transients.

[0108] Step 3.3: Based on the normalized recovery time characteristics, identify whether the alternating voltage EFI thruster is in a high / low flow state (HIGH / LOW-FLOW). Specifically:

[0109] Normalized recovery time It can be used as an indicator of propellant flow rate for estimation or grading: determined through pre-calibration. With traffic Q The corresponding relationship (inverse ratio), for example, dividing it into "high flow zone, normal zone, low flow zone"; the control system can, according to Determine if the current operating condition is high or low flow, and adjust the fluid supply flow rate if necessary. Through ground calibration tests, the upper and lower thresholds of the normalized recovery time can be determined within the design operating flow range. and Therefore, regarding the first... k The high / low flow status of each half-cycle is determined as follows:

[0110] when At that time, it was determined to be a high-flow-rate operating condition;

[0111] when At that time, it was determined to be a low flow condition.

[0112] The above states can be combined to form multi-level judgments, for example: simultaneously satisfying the overspray criterion and Extremely small, indicating "high flow overspray" conditions; simultaneously, emission attenuation and A value that is too high can indicate conditions such as "low flow attenuation".

[0113] Step 3.4: Based on the characteristics of the current attenuation coefficient, identify whether the alternating voltage EFI thruster is in a degrading state. Specifically:

[0114] Based on current attenuation coefficient The launch status can be classified into different levels, specifically: when When the thruster's launch capability is deemed good and launch attenuation is negligible; when When the condition is determined to be in a state of slight decay, it is recommended to observe or record, but forced adjustment can be temporarily suspended; when When the current is significantly reduced, the control system can trigger a maintenance / compensation mechanism, such as adjusting the propellant supply parameters and / or operating voltage, to attempt to restore the current to near the reference current. If the restoration fails, a lifespan or maintenance warning signal will be issued.

[0115] in and This is a threshold parameter, which can be obtained through ground-based calibration. In a typical embodiment, it can be selected as... , That is, when the current average steady-state current is lower than 70% of the reference current, the transmission performance is considered to have significantly degraded.

[0116] In this embodiment of the invention, a current attenuation coefficient is defined. , will recently M The average steady-state current of each half-cycle is normalized to the reference current to quantitatively reflect the degree of decay of the thruster's long-term launch capability as a single dimensionless quantity, providing a basis for on-orbit maintenance decisions and life management.

[0117] This invention combines the aforementioned dimensionless characteristic quantities to form an online operating status identification framework for alternating voltage electronic injection thrusters. It can distinguish between normal launch, over-injection state, flow rate change trend, and launch attenuation state based solely on current signals. Furthermore, it reserves control interfaces for thruster voltage, frequency, and fluid supply parameters, providing a unified technical means for achieving closed-loop operating condition optimization.

[0118] In another implementation, in addition to using fixed threshold segmentation to determine NORMAL / OVERSPRAY / HIGH(LOW)-FLOW / DEGRADED, multi-threshold grading, fuzzy rules, weighted scoring, or machine learning classifiers can also be used, as long as the corresponding working state label is still given based on the current characteristics in the end.

[0119] Step 4, Feedback Control Strategy. Based on the identified different EFI thruster states, the working fluid flow or extraction voltage controller can select one or a combination of the following typical actions:

[0120] Step 4.1, Mode = OVERSPRAY:

[0121] Reduce emitter voltage amplitude; reduce voltage polarity switching slope or extend polarity reversal transition time; adjust polarity switching frequency to reduce peak current and beam divergence.

[0122] Step 4.2, Mode = LOW-FLOW:

[0123] Increase the liquid supply or reduce the voltage to lower the average current load and avoid continuing to operate at high load under conditions of significant liquid insufficiency.

[0124] Step 4.3, Mode = HIGH-FLOW:

[0125] Reduce the liquid supply or increase the voltage to avoid excessive liquid supply flow, which could lead to unstable electronic injection or submersion of the emitter.

[0126] Step 4.4, Mode = DEGRADED:

[0127] Increase propellant back pressure or temperature to improve propellant supply conditions; fine-tune the operating voltage within permissible limits to restore target current / thrust; if multiple adjustments are ineffective, issue a thruster life or maintenance warning signal.

[0128] In summary, the embodiments of the present invention have the following beneficial effects:

[0129] (1) Relying solely on transmitted current signals. This embodiment of the invention does not require additional external diagnostic equipment. It utilizes the existing current acquisition channel of the thruster and identifies the working status through software, making it suitable for integration into a spaceborne propulsion system.

[0130] (2) To address the transient sensitivity of alternating voltage conditions, the peak value ratio is used. Ratio of valley value Defining an overspray criterion can directly reflect abnormal emission behavior at the moment of polarity reversal, which is beneficial for limiting beam divergence and gate impact caused by peak current.

[0131] (3) Recovery time is used as a flow rate indicator. A dimensionless characteristic quantity is constructed by using the time it takes for the current to recover from the valley value to the steady state. Under conditions where geometry and voltage are basically fixed, It has a monotonic relationship with propellant flow rate and can be used as a virtual flow sensor to provide a basis for flow estimation or flow grading control.

[0132] (4) Through the current attenuation coefficient Monitoring long-term launch attenuation can quantitatively reflect the slow decline of launch capability without additional diagnostic conditions, providing a basis for on-orbit maintenance decisions and lifespan management.

[0133] This method is simple and easy to implement. All features are obtained by simple time window averaging and extreme value search. It requires little computation and can run in real time on a spaceborne controller with limited resources.

[0134] Based on the foregoing embodiments, this invention provides a device for identifying the operating status of an alternating voltage electronic fuel injection thruster. (See also...) Figure 4 The diagram shows a structural schematic of an alternating voltage electronic fuel injection thruster operating status identification device, which mainly includes the following parts:

[0135] The current acquisition module 402 is used to acquire the corresponding emission current sequence of the alternating voltage electronic injection thruster in the event of a voltage polarity reversal event.

[0136] The feature extraction module 404 is used to extract the target feature quantity corresponding to the emission current sequence. The target feature quantity is used to describe the characteristics of the emission current sequence during the process of recovering from the disturbed state to the steady state after the voltage polarity reversal event occurs.

[0137] The status identification module 406 is used to identify the working status of the alternating voltage electronic injection thruster based on the target characteristic quantity. The working status includes normal stable launch status, over-injection status, high / low flow status and launch attenuation status.

[0138] The alternating voltage electronic fuel injection thruster operating status identification device provided in this embodiment of the invention can extract a limited number of simple features from the current waveform under alternating voltage conditions using only thruster emission current data, thereby achieving online identification of states such as "normal operation / severe over-injection / high or low flow rate / emission attenuation".

[0139] In one implementation, the feature extraction module 404 is specifically used for:

[0140] Determine the judgment threshold corresponding to the emission current sequence;

[0141] Based on the judgment threshold, the first emission current subsequence in the emission current sequence that meets the preset conditions is identified, and the moment corresponding to the first emission current in the emission current subsequence is taken as the stable moment of the emission current.

[0142] Based on the stable moment of the emission current, the occurrence moment of the voltage polarity reversal event, and the predefined half-cycle duration of the voltage waveform, a disturbance time window and a steady-state time window are constructed.

[0143] Feature extraction is performed on the emission current within the disturbance time window and the emission current within the steady-state time window to obtain the target feature quantity.

[0144] In one implementation, the preset condition is that the absolute value of the first-order difference of multiple consecutive transmission currents is less than or equal to a judgment threshold.

[0145] In one implementation, the feature extraction module 404 is specifically used for:

[0146] A disturbance time window is constructed, with the occurrence of the voltage polarity reversal event as the starting point and the stabilization of the emission current as the ending point.

[0147] The steady-state time window is constructed by taking the moment when the emission current stabilizes as the starting point and determining the ending point based on the occurrence time of the voltage polarity reversal event and the predefined half-cycle duration of the voltage waveform.

[0148] In one implementation, the feature extraction module 404 is specifically used for:

[0149] The mean value of the emission current within the steady-state time window is used as the steady-state current characteristic; the maximum emission current within the disturbance time window is used as the peak current characteristic; the minimum emission current within the disturbance time window is used as the valley current characteristic; and the mean value of multiple steady-state current characteristics is used as the average steady-state current characteristic.

[0150] The target characteristic quantities are obtained by dimensionlessly processing the steady-state current characteristics, peak current characteristics, valley current characteristics, average steady-state current characteristics, and the time required for the emitted current to recover from the disturbance state to the steady state.

[0151] In one implementation, the feature extraction module 404 is specifically used for:

[0152] The ratio between the peak current characteristic and the steady-state current characteristic is used as the peak current ratio characteristic.

[0153] Furthermore, the ratio between the valley current characteristic and the steady-state current characteristic is used as the valley current ratio characteristic;

[0154] In addition, the ratio between the average steady-state current characteristic and the preset emission reference current is used as the current attenuation coefficient characteristic;

[0155] In addition, the ratio between the time required for the emitted current to recover from the disturbance state to the steady state and the predefined half-cycle duration of the voltage waveform is used as a normalized recovery time feature;

[0156] The peak current ratio, valley current ratio, current decay coefficient, and normalized recovery time are used as target feature quantities.

[0157] In one implementation, the state recognition module 406:

[0158] Based on the characteristics of peak current ratio, valley current ratio, and normalized recovery time, it is possible to identify whether the alternating voltage electronic injection thruster is in a normal and stable launch state.

[0159] Based on the characteristics of peak current ratio and valley current ratio, it is possible to identify whether the alternating voltage electronic injection thruster is in an over-injection state.

[0160] Based on the normalized recovery time characteristics, it is possible to identify whether the alternating voltage electronic injection thruster is in a high / low flow state.

[0161] Based on the characteristics of the current attenuation coefficient, it is possible to identify whether the alternating voltage electronic fuel injection thruster is in a launch attenuation state.

[0162] The device provided in this embodiment of the invention has the same implementation principle and technical effect as the aforementioned method embodiment. For the sake of brevity, any parts not mentioned in the device embodiment can be referred to the corresponding content in the aforementioned method embodiment.

[0163] This invention provides an electronic device, specifically, the electronic device includes a processor and a memory; the memory stores a computer program, which, when run by the processor, executes the method described in any of the above embodiments.

[0164] Figure 5 The present invention provides a schematic diagram of the structure of an electronic device 100, which includes a processor 50, a memory 51, a bus 52 and a communication interface 53. The processor 50, the communication interface 53 and the memory 51 are connected through the bus 52. The processor 50 is used to execute executable modules, such as computer programs, stored in the memory 51.

[0165] The memory 51 may include high-speed random access memory (RAM) or non-volatile memory, such as at least one disk storage device. Communication between this system network element and at least one other network element is achieved through at least one communication interface 53 (which can be wired or wireless), such as the Internet, wide area network, local area network, metropolitan area network, etc.

[0166] Bus 52 can be an ISA bus, PCI bus, or EISA bus, etc. The bus can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 5 The symbol is represented by a single double-headed arrow, but this does not mean that there is only one bus or one type of bus.

[0167] The memory 51 is used to store programs. After receiving an execution instruction, the processor 50 executes the programs. The method executed by the device for defining the flow process disclosed in any of the foregoing embodiments of the present invention can be applied to the processor 50 or implemented by the processor 50.

[0168] Processor 50 may be an integrated circuit chip with signal processing capabilities. In implementation, each step of the above method can be completed by the integrated logic circuitry in the hardware of processor 50 or by instructions in software form. Processor 50 can be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it can also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this invention. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this invention can be directly embodied in the execution of a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software modules can reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. The storage medium is located in memory 51. The processor 50 reads the information in memory 51 and, in conjunction with its hardware, completes the steps of the above method.

[0169] The computer program product of the readable storage medium provided in the embodiments of the present invention includes a computer-readable storage medium storing program code. The instructions included in the program code can be used to execute the methods described in the foregoing method embodiments. For specific implementation, please refer to the foregoing method embodiments, which will not be repeated here.

[0170] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0171] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, 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, and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for identifying the operating state of an alternating voltage electronic fuel injection thruster, characterized in that, include: In the event of a voltage polarity reversal event in the alternating voltage electronic fuel injection thruster, the corresponding emission current sequence of the alternating voltage electronic fuel injection thruster is collected; Extract the target feature quantity corresponding to the emission current sequence. The target feature quantity is used to describe the characteristics of the emission current sequence during the process of recovering from the disturbed state to the steady state after the voltage polarity reversal event occurs. The operating state of the alternating voltage electronic injection thruster is identified based on the target feature quantity. The operating state includes normal stable launch state, over-injection state, high / low flow state, and launch attenuation state. Extracting the target feature quantities corresponding to the emission current sequence includes: Determine the judgment threshold corresponding to the emission current sequence; Based on the judgment threshold, the first subsequence of the emission current that meets the preset condition is identified in the emission current sequence, and the time corresponding to the first emission current in the emission current subsequence is taken as the stable time of the emission current. The preset condition is that the absolute value of the first difference of multiple consecutive emission currents is less than or equal to the judgment threshold. Based on the stable emission current moment, the occurrence moment of the voltage polarity reversal event, and the predefined half-cycle duration of the voltage waveform, a disturbance time window and a steady-state time window are constructed, including: A disturbance time window is constructed with the occurrence time of the voltage polarity reversal event as the starting point and the stabilization time of the emission current as the ending point; a steady-state time window is constructed with the stabilization time of the emission current as the starting point and the ending point determined according to the occurrence time of the voltage polarity reversal event and the predefined half-cycle duration of the voltage waveform. Feature extraction is performed on the emission current within the disturbance time window and the emission current within the steady-state time window to obtain the target feature quantity.

2. The method for identifying the operating state of an alternating voltage electronic fuel injection thruster according to claim 1, characterized in that, Feature extraction is performed on the emission current within the disturbance time window and the emission current within the steady-state time window to obtain target feature quantities, including: The average value of the emission current within the steady-state time window is taken as the steady-state current characteristic; and the maximum emission current within the disturbance time window is taken as the peak current characteristic; and the minimum emission current within the disturbance time window is taken as the valley current characteristic; and the average value of multiple steady-state current characteristics is taken as the average steady-state current characteristic. The steady-state current characteristic, the peak current characteristic, the valley current characteristic, the average steady-state current characteristic, and the time required for the emitted current to recover from the disturbance state to the steady state are processed in a dimensionless manner to obtain the target characteristic quantity.

3. The method for identifying the operating state of an alternating voltage electronic fuel injection thruster according to claim 2, characterized in that, The steady-state current characteristic, the peak current characteristic, the valley current characteristic, the average steady-state current characteristic, and the time required for the emitted current to recover from the disturbance state to the steady state are subjected to dimensionless processing to obtain the target characteristic quantity, including: The ratio between the peak current characteristic and the steady-state current characteristic is used as the peak current ratio characteristic. Furthermore, the ratio between the valley current characteristic and the steady-state current characteristic is used as the current valley ratio characteristic; Furthermore, the ratio between the average steady-state current characteristic and the preset transmission reference current is used as the current attenuation coefficient characteristic; Furthermore, the ratio of the time required for the transmitted current to recover from the disturbed state to the steady state to the predefined half-cycle duration of the voltage waveform is used as a normalized recovery time feature; The peak current ratio, valley current ratio, current attenuation coefficient, and normalized recovery time are used as target feature quantities.

4. The method for identifying the operating state of an alternating voltage electronic fuel injection thruster according to claim 3, characterized in that, Identifying the operating state of the alternating voltage electronic fuel injection thruster based on the target feature quantity includes: Based on the current peak ratio characteristic, the current valley ratio characteristic, and the normalized recovery time characteristic, it is determined whether the alternating voltage electronic injection thruster is in the normal stable launch state; Based on the current peak ratio characteristic and the current valley ratio characteristic, it is determined whether the alternating voltage electronic injection thruster is in the over-injection state; Based on the normalized recovery time characteristics, it is determined whether the alternating voltage electronic injection thruster is in the high / low flow state; Based on the current attenuation coefficient characteristics, it is determined whether the alternating voltage electronic injection thruster is in the launch attenuation state.

5. A device for identifying the operating status of an alternating voltage electronic fuel injection thruster, characterized in that, include: The current acquisition module is used to acquire the emission current sequence corresponding to the alternating voltage electronic fuel injection thruster in the event of a voltage polarity reversal event. The feature extraction module is used to extract the target feature quantity corresponding to the emission current sequence. The target feature quantity is used to describe the characteristics of the emission current sequence during the process of recovering from the disturbed state to the steady state after the voltage polarity reversal event occurs. The status recognition module is used to identify the operating status of the alternating voltage electronic injection thruster according to the target feature quantity. The operating status includes normal stable launch status, over-injection status, high / low flow status and launch attenuation status. The feature extraction module is specifically used for: Determine the judgment threshold corresponding to the emission current sequence; Based on the judgment threshold, the first subsequence of the emission current that meets the preset condition is identified in the emission current sequence, and the time corresponding to the first emission current in the emission current subsequence is taken as the stable time of the emission current. The preset condition is that the absolute value of the first difference of multiple consecutive emission currents is less than or equal to the judgment threshold. Based on the stable emission current moment, the occurrence moment of the voltage polarity reversal event, and the predefined half-cycle duration of the voltage waveform, a disturbance time window and a steady-state time window are constructed, including: A disturbance time window is constructed with the occurrence time of the voltage polarity reversal event as the starting point and the stabilization time of the emission current as the ending point; a steady-state time window is constructed with the stabilization time of the emission current as the starting point and the ending point determined according to the occurrence time of the voltage polarity reversal event and the predefined half-cycle duration of the voltage waveform. Feature extraction is performed on the emission current within the disturbance time window and the emission current within the steady-state time window to obtain the target feature quantity.

6. An electronic device, characterized in that, The method includes a processor and a memory, the memory storing computer-executable instructions executable by the processor, the processor executing the computer-executable instructions to implement the method of any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions that, when invoked and executed by a processor, cause the processor to perform the method described in any one of claims 1 to 4.

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