Hall thruster contact and heating constant current power supply control method and device

Abstract

The application discloses a Hall thruster touch and heating constant-current power supply control method and device, relates to the technical field of power supply control, and comprises the following steps: detecting the heating current change rate of a heating power supply, identifying the impedance of a touch power supply based on the equivalent impedance value of a cathode, and jointly determining cathode state data, wherein the cathode state data contains a launch preparation state and an arc occurrence state; the cathode working state is divided into preheating preparation, arc waiting, arc transition and self-sustaining discharge, a cathode state machine is arranged, according to the cathode state data, state switching is performed in the cathode state machine, feedforward and feedback collaborative control decisions are made in a state machine event triggering mode, the touch power supply is subjected to constant-current regulation and management, and the technical problem that the refinement and stability of power supply regulation are limited in the prior art can be solved, and the refinement and stability of power supply regulation can be effectively improved.

Description

Technical Field

[0001] This invention relates to the field of power control technology, specifically to a method and apparatus for controlling a Hall effect actuator holding and heating constant current power supply. Background Technology

[0002] During the ground testing and in-orbit application of Hall thrusters, the cathode heating power supply and the contact power supply are key power conversion devices to ensure the normal start-up and stable operation of the thruster. Before ignition, the cathode needs to be heated to the thermionic emission temperature by the heating power supply, and then the contact power supply establishes an electric field to ignite the discharge between the cathode and the anode, ultimately achieving self-sustaining discharge.

[0003] In existing technologies, heating power supplies and contact power supplies typically employ independent constant current or constant voltage control strategies, lacking an effective information exchange and coordination mechanism between them. Heating power supplies often rely on open-loop timed heating or a single temperature threshold judgment, making it difficult to accurately sense whether the cathode thermal state has reached the emission conditions. Contact power supplies generally use conventional closed-loop current feedback regulation. When the equivalent impedance of the cathode undergoes a drastic change at the moment of arc ignition, traditional feedback control is prone to current overshoot or drop due to inherent delay, leading to arc ignition failure or contact power supply overload protection.

[0004] In summary, existing control schemes suffer from control lag when the arc-starting impedance drops sharply, resulting in large arc-starting current spikes. They also fail to effectively predict the cathode emission state, leading to easy cathode ablation and difficulty in adapting to full-condition performance requirements. This results in technical problems that limit the precision and stability of power supply regulation. Summary of the Invention

[0005] This application provides a method and apparatus for controlling the constant current power supply for Hall thruster holding and heating, which solves the technical problems of limited precision and stability of power supply regulation in the prior art.

[0006] In view of the above problems, this application provides a method and apparatus for controlling the Hall thruster holding and heating constant current power supply.

[0007] This application provides a method for controlling the constant current power supply for a Hall thruster's holding and heating system. The method includes: detecting the rate of change of heating current in the heating power supply, performing impedance identification on the holding power supply based on the equivalent cathode impedance value, and jointly determining cathode state data, wherein the cathode state data includes a launch preparation state and an arc initiation state; deploying a cathode state machine by dividing the cathode working state into preheating preparation, arc initiation, arc transition, and self-sustaining discharge; and, based on the cathode state data, using a state machine event triggering method in the cathode state machine to perform feedforward and feedback coordinated control decisions under state switching, and performing constant current regulation management on the holding power supply, wherein each working state stage defines entry and exit conditions; wherein the feedforward and feedback coordinated control decisions include: using the rate of change of impedance value based on impedance identification as input, calculating the feedforward PWM duty cycle based on a negative over-threshold using a feedforward compensator; and using the deviation between the actual current and the target current as input, determining the feedback PWM duty cycle based on PID analysis under the feedback control loop.

[0008] This application provides a Hall thruster holding and heating constant current power supply control device, the device comprising: a state detection module: which detects the heating current change rate of the heating power supply, performs impedance identification of the holding power supply based on the cathode equivalent impedance value, and jointly determines the cathode state data, wherein the cathode state data includes the launch preparation state and the arc initiation state; a constant current control module: which divides the cathode working state into preheating preparation, waiting for arc initiation, arc initiation transition, and self-sustaining discharge, deploys a cathode state machine, and, based on the cathode state data, uses a state machine event triggering method to perform feedforward and feedback coordinated control decisions under state switching, and performs constant current regulation management of the holding power supply, wherein each working state stage defines entry and exit conditions; wherein the feedforward and feedback coordinated control decisions include: a feedforward decision unit: which takes the impedance value change rate based on impedance identification as input, calculates the feedforward PWM duty cycle based on the negative over-threshold according to the feedforward compensator; and a feedback decision unit: which takes the deviation between the actual current and the target current as input, and determines the feedback PWM duty cycle according to PID analysis under the feedback control loop.

[0009] One or more technical solutions provided in this application have at least the following technical effects or advantages:

[0010] This application provides a Hall thruster holding and heating constant current power supply control method. By detecting the heating current change rate of the heating power supply and performing impedance identification of the holding power supply based on the cathode equivalent impedance value, cathode state data is jointly determined. The cathode state data includes a launch preparation state and an arc initiation state. By dividing the cathode operating state into preheating preparation, arc initiation, arc transition, and self-sustaining discharge, a cathode state machine is deployed. Based on the cathode state data, a state machine event triggering method is used in the cathode state machine to perform feedforward and feedback coordinated control decisions under state switching, thereby managing the constant current of the holding power supply. This method addresses the technical problem of limited precision and stability in power supply control in existing technologies, effectively improving the precision and stability of power supply control. Attached Figure Description

[0011] Figure 1 This application provides a schematic flowchart of a Hall thruster holding and heating constant current power supply control method.

[0012] Figure 2 This application provides a schematic diagram of a Hall thruster holding and heating constant current power supply control device.

[0013] Figure labeling: State detection module 1, constant current control module 2, feedforward decision unit 21, feedback decision unit 22. Detailed Implementation

[0014] This application provides a method for controlling the constant current power supply for Hall thruster holding and heating, which solves the technical problems of limited precision and stability of power supply regulation in the prior art.

[0015] Example 1: As Figure 1 As shown, this application provides a method for controlling a Hall effect actuator's holding and heating constant current power supply, the method comprising:

[0016] S1: By detecting the rate of change of heating current of the heating power supply, impedance identification based on the cathode equivalent impedance value is performed on the holding power supply, and cathode state data is jointly determined. The cathode state data includes the launch preparation state and the arc initiation state.

[0017] In this embodiment, to accurately sense the working state of the Hall thruster cathode, it is first necessary to perform coordinated detection of the heating power supply and the contact power supply. Specifically, the output current of the heating power supply is continuously sampled, and the time-based current change rate is calculated in real time according to a preset sampling rate. By comparing the absolute value of this current change rate with a threshold, it is determined whether the heating current has entered the steady-state region.

[0018] When the absolute value is lower than the preset threshold, it indicates that the cathode heating power and heat dissipation power have reached a dynamic balance, the cathode temperature tends to stabilize and reach the temperature threshold required for thermionic emission, which means that the cathode has entered the thermal ready state.

[0019] As an example, the preset sampling rate can be set from 1kHz to 10kHz, and the current change rate threshold can be set to 0.5% / ms of the rated current. The specific values ​​are determined based on the thermal time constant and power level of the cathode heating wire.

[0020] Meanwhile, a high-frequency small signal excitation is superimposed on the output of the power supply, and the equivalent impedance value of the cathode is calculated in real time by detecting the amplitude attenuation and phase shift of the response signal, which is used as the impedance identification result.

[0021] Among them, the frequency selection of high-frequency small signals should avoid the switching frequency of the contact power supply and its harmonics. Typically, it can be set to 1 / 4 or 1 / 3 of the switching frequency, and the amplitude should be controlled within 1% of the contact output voltage to avoid interference to the main power circuit.

[0022] For example, impedance identification can be performed by using synchronous demodulation or Fourier analysis to extract the fundamental component of the response signal to obtain the impedance value.

[0023] After obtaining the heating current change rate determination result and the contact end impedance identification result, the two are combined and logically determined to determine the cathode state data.

[0024] Specifically, when the absolute value of the rate of change of the heating current is lower than a preset threshold and remains so for a predetermined time, and the impedance identification result shows that the cathode equivalent impedance is decreasing from the first high-resistance state, the cathode is determined to have entered the emission preparation state. This state indicates that the cathode temperature has met the emission conditions and the holding electric field can be safely applied.

[0025] When the absolute value of the rate of change of heating current remains below a preset threshold, and the impedance identification results show that the equivalent impedance of the cathode drops sharply below the second low-resistance state threshold, the cathode is determined to have entered the arc initiation state. This sudden drop in impedance is caused by the breakdown of the air gap between the cathode and the anode to form a plasma channel, resulting in a sharp decrease in the equivalent resistance, which is a typical electrical sign of the moment of arc initiation.

[0026] Optionally, the first high-resistivity state corresponds to the high-resistivity range of the cold or hot state when the cathode is not emitting, and its resistance value is usually in the range of several ohms to tens of ohms; the second low-resistivity state threshold corresponds to the low-resistivity conduction state after the plasma is established, and its resistance value is usually in the range of 0.1 ohms to several ohms. The specific threshold is calibrated according to the propulsion structure and the type of working fluid.

[0027] By combining the above-mentioned mechanism of detecting the rate of change of heating current with the identification of contact impedance, the thermal preparation stage and the arc initiation transient stage of the cathode can be accurately distinguished, providing a reliable triggering basis for subsequent state machine state switching and feedforward control. The joint sensing method overcomes the risk of misjudgment associated with single electrical parameter discrimination, and in particular avoids false triggering caused by electromagnetic noise interference at the moment of arc initiation when relying solely on voltage or current thresholds.

[0028] Furthermore, to determine the cathode state data, step S1 of this application includes:

[0029] According to a preset sampling rate, the output current value of the heating power supply is collected in real time and the current change rate is continuously calculated. The cathode state sensing result is determined by judging the absolute value of the current change rate against a preset threshold. When the absolute value is less than the preset threshold, the cathode state sensing result indicates that the heating current has entered the steady-state region, the cathode thermal state tends to be in equilibrium, and the temperature is determined to have reached the emission threshold. A high-frequency small signal is superimposed at the output end of the contact power supply. By detecting the amplitude attenuation and phase shift of the response signal, the cathode equivalent impedance value is calculated in real time as the impedance identification result of the contact end. The cathode state data is obtained by comprehensively judging the cathode state sensing result and the impedance identification result.

[0030] In this embodiment, to accurately perceive the cathode thermal state, the output current of the heating power supply is first monitored in real time. Specifically, the output current value of the heating power supply is continuously collected according to a preset sampling rate, and the current change relative to the previous moment is calculated and divided by the sampling interval in each sampling period to obtain the real-time current change rate.

[0031] The sampling rate setting needs to balance detection accuracy and computational cost. As an example rather than a limitation, it can be set to 1kHz~10kHz to adapt to the thermal time constant of the cathode heating wire. Subsequently, the absolute value of the calculated current change rate is taken and compared with a preset threshold to determine whether the heating current has entered the steady-state region.

[0032] When the absolute value is less than the preset threshold, it indicates that the heating current change is becoming gradual, the cathode absorption power and dissipation power reach a dynamic balance, and the thermal state is becoming stable. Based on this, it is determined that the cathode temperature has reached the emission threshold required for thermionic emission, and this determination result is the cathode state sensing result.

[0033] At the same time, in order to sense the changes in the electrical characteristics of the contact end, a high-frequency small signal excitation is superimposed on the output end of the contact power supply.

[0034] Preferably, the frequency of the high-frequency small signal should avoid the main power switching frequency and its harmonic components of the contact power supply to prevent power interference. Typically, it can be selected as 1 / 4 to 1 / 3 of the switching frequency, and the amplitude should be controlled within 1% of the rated value of the contact output voltage to ensure that it does not interfere with the main power output. Based on this, by detecting the amplitude attenuation and phase shift of the response signal, combined with the known amplitude and phase of the excitation signal, the equivalent impedance value of the cathode terminal is calculated in real time using the AC form of Ohm's law. This includes the equivalent resistance of the real part and the equivalent reactance of the imaginary part, which serves as the impedance identification result of the contact terminal.

[0035] Furthermore, after obtaining the cathode state sensing results at the heating end and the impedance identification results at the contact end, a comprehensive logical judgment is made on the two to finally determine the cathode state data.

[0036] Specifically, the thermal readiness state, characterized by the absolute value of the heating current change rate being less than a preset threshold, is combined with the trend and amplitude range of the impedance identification results: if the impedance value shows a trend of gradually decreasing from the high resistance state, it indicates that the cathode surface barrier is reduced and the emission capability is enhanced, and it is determined to be in the emission preparation state; if the impedance value drops sharply to below the low resistance state threshold, it indicates that a plasma conduction channel has been formed between the cathode and the anode, and it is determined to be in the arc initiation state.

[0037] In summary, through the cross-verification of the steady-state determination of the heating end and the impedance change trend of the holding end, the thermal preparation stage and the arc-starting transient stage can be accurately distinguished, providing reliable state data input for the event triggering of the state machine, while avoiding misjudgment caused by electromagnetic noise or load fluctuations of a single electrical parameter.

[0038] Furthermore, step S1 of this application includes:

[0039] If the cathode state sensing result is that the heating current is stable and the impedance identification result is that the impedance starts to decrease from the first high resistance state, it is determined to be in the launch preparation state, wherein the launch preparation state triggers the cathode state machine to proceed to the next stage; if the cathode state sensing result is that the heating current is stable and the impedance identification result is that the impedance drops sharply to the second low resistance state threshold, it is determined to be in the arc initiation state, wherein the arc initiation state triggers constant current loop feedforward compensation.

[0040] In this embodiment, when the cathode state sensing result shows that the absolute value of the heating current change rate is continuously less than a preset threshold, indicating that the heating current has entered the steady-state region and the cathode thermal state is approaching equilibrium, and the impedance identification result shows that the cathode equivalent impedance value shows a monotonically decreasing trend starting from a preset first high-resistivity state, then the cathode is determined to be in a launch preparation state. The first high-resistivity state corresponds to the intrinsic impedance range of the cathode when no thermionic emission has occurred or the emission is not yet sufficient. Its specific numerical range is related to the cathode material, temperature, and propellant type, and can be predetermined through ground calibration tests.

[0041] Among them, the launch preparation state is a state machine event that triggers the cathode state machine to enter the next working stage from the current stage, that is, triggers the arc ignition program to start the contact power supply output in order to establish the arc ignition electric field.

[0042] Meanwhile, when the cathode state sensing result also indicates that the heating current is stable and the cathode thermal state meets the emission conditions, and the impedance identification result shows that the cathode equivalent impedance value drops sharply from the first high-resistivity state to below the preset second low-resistivity state threshold, then it is determined that the cathode is currently in an arc-initiating state. The second low-resistivity state threshold corresponds to the low-resistivity conduction range after the air gap between the cathode and anode is broken down and the plasma conductive channel is established. Its impedance value is much lower than that of the first high-resistivity state, typically ranging from 0.1 ohms to several ohms.

[0043] Among them, the arc initiation state is another state machine event, which triggers the constant current loop feedforward compensation to intervene. That is, the feedforward compensator calculates the compensation amount based on the impedance change rate amplitude and adds it to the PWM duty cycle to suppress the current disturbance caused by the sudden change in load impedance at the moment of arc initiation and ensure the smooth transition of the holding current.

[0044] Through the dual-condition determination mechanism based on heating steady-state determination and impedance change trend and amplitude threshold cross-verification, the two key state events of launch preparation and arc initiation can be accurately distinguished, providing a clear and reliable trigger signal for the state machine.

[0045] S2: By dividing the cathode working state into preheating preparation, waiting for arc ignition, arc ignition transition, and self-sustaining discharge, a cathode state machine is deployed. Based on the cathode state data, the cathode state machine adopts a state machine event triggering method to make feedforward and feedback coordinated control decisions under state switching, and performs constant current regulation management of the contact power supply. Among them, entry conditions and exit conditions are defined for each working state stage.

[0046] The feedforward and feedback coordinated control decision includes: taking the impedance value change rate based on impedance identification as input, calculating the feedforward PWM duty cycle based on the negative over-threshold according to the feedforward compensator; taking the deviation between the actual current and the target current as input, determining the feedback PWM duty cycle according to the PID analysis under the feedback control loop.

[0047] In this embodiment, in order to achieve constant current regulation and management of the contact power supply under all operating conditions, the cathode is first divided into several quantifiable state stages according to the physical process of cathode operation, and a cathode state machine is deployed accordingly.

[0048] Specifically, the cathode operating state is divided into four stages: preheating preparation, arc initiation, arc transition, and self-sustaining discharge. Each stage has clearly defined entry and exit conditions. The preheating preparation stage corresponds to the process of starting the heating power supply and raising the cathode temperature from room temperature to the emission threshold. Its entry condition is that the heating command is valid, and its exit condition is that the absolute value of the heating current change rate is lower than the preset threshold and the impedance identification result begins to decrease. The arc initiation stage corresponds to the process of the cathode reaching the thermal emission condition and waiting for the application of the contact electric field. Its entry condition is that the emission preparation state is triggered, and its exit condition is that the arc initiation state is triggered. The arc transition stage corresponds to the process of gas gap breakdown between the cathode and anode and the establishment of the plasma channel. Its entry condition is that the arc initiation state is triggered, and its exit condition is that the contact current enters a steady state and the impedance value stabilizes in a low-resistance state. The self-sustaining discharge stage corresponds to the process of the discharge being fully established and independently maintained. Its entry condition is that the arc initiation is completed and the current remains in a steady state for a predetermined time, and its exit condition is an external shutdown command or a fault protection signal.

[0049] Based on the cathode state data obtained from the aforementioned joint identification, a state machine event triggering method is adopted in the cathode state machine, that is, the corresponding control action is triggered only when a specific state event occurs, rather than being executed continuously in a loop, thereby reducing computational overhead and improving response determinism.

[0050] When the state machine switches states, it synchronously executes feedforward and feedback coordinated control decisions to perform constant current regulation and management of the contact power supply.

[0051] Specifically, the feedforward and feedback coordinated control decision includes the following control paths executed in parallel.

[0052] In the feedforward control path, the rate of change of the cathode equivalent impedance value obtained based on impedance identification is used as the input and is fed into a pre-configured feedforward compensator. This feedforward compensator internally stores a mapping relationship between the impedance change rate threshold and the compensation magnitude. When the feedforward compensator detects that the impedance change rate is negative and its absolute value exceeds the preset change rate threshold, it is determined to be a sudden load drop event at the moment of arc initiation. Then, based on the magnitude of the impedance change rate, the corresponding feedforward compensation amount is calculated according to the mapping relationship, and the feedforward PWM duty cycle is determined based on this feedforward compensation amount.

[0053] The negative over-threshold refers to the rapid decrease in impedance value beyond the normal fluctuation range, which is a typical electrical sign of arc initiation. Based on this, the feedforward compensator acts in advance before the feedback loop responds, so as to achieve advance correction.

[0054] In the feedback control path, the deviation between the actual collected holding current value and the preset target current value is used as the input quantity and is introduced into the pre-deployed feedback control loop. The feedback control loop uses PID control to perform proportional-integral calculation on the deviation, determines the feedback correction quantity based on the calculation result, and determines the feedback PWM duty cycle accordingly.

[0055] Through the parallel calculation and output coordination of the above-mentioned feedforward and feedback, the feedforward path is responsible for suppressing the sudden current disturbance at the moment of arc initiation, and the feedback path is responsible for eliminating steady-state deviation and ensuring long-term accuracy. The two work together to achieve constant current regulation of the contact power supply during the entire state switching process.

[0056] Furthermore, in the cathode state machine, a state machine event triggering method is adopted. Step S2 of this application includes:

[0057] A cathode state machine is established by dividing the cathode working state. If the cathode state data is in the launch preparation state, it is treated as the first state machine event. According to the cathode state machine, the arc initiation program is triggered to start the holding power supply. If the cathode state data is in the arc initiation state, it is treated as the second state machine event. According to the cathode state machine, the constant current loop feedforward compensation is triggered, and the ignition power supply is started synchronously.

[0058] In this embodiment, the working state of the cathode is first divided into stages based on the complete physical process of the Hall thruster cathode from cold start to fully self-sustaining discharge, and a cathode state machine is established based on the division results.

[0059] Specifically, the cathode working state includes at least a preheating preparation stage, an arc ignition stage, an arc ignition transition stage, and a self-sustaining discharge stage. The entry and exit conditions for each stage are preset and fixed in the state machine based on the joint judgment results of the aforementioned heating current change rate detection and contact end impedance identification.

[0060] The preheating preparation stage is a separate operating zone for the heating power supply, during which both the contact power supply and the ignition power supply are turned off. The arc ignition stage is a waiting zone where heating is complete and the contact power supply is ready to be activated. The arc ignition transition stage is the transient zone from the establishment of the contact electric field to the complete formation of the discharge. The self-sustaining discharge stage is the operating zone where the discharge is stably maintained. Through the above stage division and state machine deployment, a structured decision framework is provided for subsequent event-triggered control.

[0061] Based on this, when the cathode state data is confirmed as a launch preparation state through joint determination, the state data serves as a first state machine event to trigger the cathode state machine to execute the corresponding state switching action.

[0062] Specifically, the emission preparation state corresponds to the operating condition where the absolute value of the heating current change rate is lower than a preset threshold and the cathode equivalent impedance begins to decrease from the first high-resistance state, indicating that the cathode temperature has met the requirements for thermionic emission and the holding electric field can be safely applied. Accordingly, the cathode state machine, based on the current arc-initiating stage, responds to the first state machine event, triggers the arc-initiating program to start the holding power supply, enables the power switch drive signal of the holding power supply, and causes the holding power supply to start building up the output voltage, forming an arc-initiating electric field between the cathode and anode in preparation for arc initiation.

[0063] Preferably, the starting process of this application adopts a soft start method, in which the output voltage rises from zero to the set value of the arc-starting voltage according to a preset slope, so as to avoid the voltage step causing electrical shock to the cathode.

[0064] Meanwhile, when the cathode state data is confirmed as an arc initiation state through joint determination, the state data serves as a second state machine event to trigger the cathode state machine to execute another set of state switching and cooperative control actions.

[0065] Specifically, the arc initiation state corresponds to the working condition where the heating current is stable and the cathode equivalent impedance drops sharply to below the second low resistance threshold, indicating that the air gap between the cathode and anode has been broken down, the plasma conductive channel has been initially established, and the holding current will show a rapid upward trend due to the sharp drop in load impedance.

[0066] Accordingly, in response to the second state machine event, the cathode state machine triggers the constant current loop feedforward compensation, that is, it starts the aforementioned feedforward compensator to calculate the feedforward PWM duty cycle based on the impedance change rate amplitude and superimposes it onto the control loop to suppress current overshoot before the feedback loop responds; on the other hand, it synchronously triggers the ignition power supply to start, enables the ignition power supply output, and provides ignition energy to the anode to maintain and expand the plasma discharge channel, ensuring that the arc ignition process is reliably completed.

[0067] The ignition power source is a high-voltage pulse source, used to break down the gas gap between the cathode and anode to ignite the main discharge; the holding power source is a constant current source, used to maintain the stable self-sustaining of the cathode discharge after successful ignition. The two form a sequential relationship of breakdown followed by maintenance in the ignition process, that is, the ignition power source is responsible for ignition, and the holding power source is responsible for arc stabilization.

[0068] In summary, by triggering and coordinating the timing of the first and second state machine events, fully automatic sequential control of the cathode from thermal preparation to discharge establishment is achieved.

[0069] Furthermore, before making feedforward and feedback coordinated control decisions under state switching, the configuration of the feedforward compensator and feedback control loop, step S2 of this application includes:

[0070] For the contact power supply, feedforward control parameters are configured and a feedforward compensator is deployed. The feedforward control parameters include an impedance change rate threshold, a compensation amplitude mapping coefficient, and a compensation attenuation time constant. For the contact power supply, feedback PID parameters based on the power supply operating conditions are configured. The operating conditions of the contact power supply include no-load condition, arc-starting transition condition, and steady-state discharge condition. The no-load condition uses a first proportional gain and a first integral gain, the arc-starting transition condition uses a second proportional gain and a second integral gain, and the steady-state discharge condition uses a third proportional gain and a third integral gain. A feedback control loop is deployed according to the feedback PID parameters.

[0071] In this embodiment, in order to implement the aforementioned feedforward and feedback coordinated control strategy, it is first necessary to configure feedforward control parameters and deploy feedforward compensators for the contact power supply, and configure feedback PID parameters based on power supply conditions and deploy feedback control loops.

[0072] Specifically, regarding the feedforward configuration, feedforward control parameters are configured for the contact power supply, and a feedforward compensator is deployed. The feedforward control parameters include at least an impedance change rate threshold, a compensation magnitude mapping coefficient, and a compensation attenuation time constant.

[0073] The impedance change rate threshold is used to determine whether to trigger the feedforward compensation action. Its specific value is set based on the statistical calibration results of the impedance change characteristics of the cathode at the moment of arc initiation. As an example rather than a limitation, it can be set to an impedance change rate exceeding 5% to 10% of the rated impedance per millisecond as the trigger threshold. The compensation amount amplitude mapping coefficient is used to map the amplitude of the impedance change rate to the corresponding feedforward PWM duty cycle compensation amount. This mapping relationship can be implemented by linear relationship or lookup table method. For example, the specific coefficient value is obtained by linear fitting of measured or simulated data. The compensation decay time constant is used to control the rate at which the feedforward compensation amount gradually decays to zero after the arc initiation is completed. Its value is matched with the response speed of the feedback loop. Typically, it can be set to 1.5 to 2 times the response time of the feedback loop to ensure that the feedforward exit process is smooth and does not cause secondary disturbances.

[0074] After the above parameters are configured, the feedforward compensator is deployed in the control link of the power supply, so that it can receive the impedance identification result in real time and output the feedforward PWM duty cycle.

[0075] Regarding the feedback channel configuration, feedback PID parameters based on the power supply operating conditions are configured for the contact power supply. The operating conditions of the contact power supply include at least no-load operating conditions, arcing transition operating conditions, and steady-state discharge operating conditions. The load characteristics differ significantly under different operating conditions, requiring differentiated PID parameters to achieve optimal control across all operating conditions.

[0076] Specifically, the no-load condition corresponds to the state where the power supply has been started to establish the output voltage, but the cathode has not yet started to arc. At this time, the load impedance is in a high-resistance state, the current loop is open, and the first proportional gain and the first integral gain are used. In the no-load condition, the load is in a high-resistance state and the current feedback is weak. The high proportional gain is used to ensure that the voltage is established quickly, and the low integral gain is used to prevent the output voltage from overshooting due to integral saturation.

[0077] The arc-starting transition condition corresponds to the transient process where arcing occurs and the load impedance changes drastically from a high resistance state to a low resistance state. At this time, the current loop switches from an open loop to a closed loop, and the load changes drastically. A second proportional gain and a second integral gain are used. The second proportional gain is greater than the first proportional gain to improve the fast tracking capability of the current loop, and the second integral gain is greater than the first integral gain to avoid integral lag affecting the dynamic response speed.

[0078] The steady-state discharge condition corresponds to the state where arc initiation is completed and the plasma channel is stably maintained. At this time, the load impedance is stable and low-resistance. Current ripple and steady-state accuracy are the focus. A third proportional gain and a third integral gain are adopted. The value of the third proportional gain is less than that of the second proportional gain to ensure system stability and reduce noise sensitivity. The value of the third integral gain is greater than that of the second integral gain to improve steady-state accuracy and eliminate static error.

[0079] As an example rather than a limitation, each gain value can be determined by tuning using the critical ratio and the measured step response curve, and set as a known value on the user side.

[0080] Based on the configured feedback PID parameters, a feedback control loop is deployed, enabling the loop to select and load the corresponding PID parameter group in real time according to the current operating conditions. The PID calculation is performed with the deviation between the actual current and the target current as input, and the feedback correction amount is output to determine the feedback PWM duty cycle.

[0081] In summary, the independent configuration and coordinated deployment of the feedforward compensator and feedback control loop provide a complete execution basis for coordinated control decisions under subsequent state switching.

[0082] Furthermore, in making coordinated control decisions between feedforward and feedback during state transitions, step S2 of this application includes:

[0083] If constant current loop feedforward compensation is triggered, the impedance value change rate is used as input to the feedforward compensator based on the impedance identification result. When the impedance value change rate negatively exceeds the preset change rate threshold, the feedforward compensation amount is calculated based on the amplitude of the impedance change rate. The feedforward compensation amount gradually decays to zero as the amplitude of the impedance change rate decreases. The feedforward PWM duty cycle is determined based on the feedforward compensation amount.

[0084] Further includes:

[0085] Based on the feedback control loop, the deviation between the actual current and the target current is used as input to determine the feedback correction amount; based on the feedback correction amount, the feedback PWM duty cycle is determined; and the timing coordination between the feedforward PWM duty cycle and the feedback PWM duty cycle is used to perform constant current regulation on the contact power supply.

[0086] In this embodiment, during the specific execution of the feedforward control path, when the cathode state machine triggers constant current loop feedforward compensation in response to the arc initiation state, it first imports the pre-configured and deployed feedforward compensator with the rate of change of the cathode equivalent impedance value as the input, based on the aforementioned impedance identification results. The feedforward compensator continuously receives the real-time updated impedance change rate data and determines whether the impedance change rate meets the feedforward triggering condition.

[0087] Specifically, when the rate of change of impedance is negative and its absolute value exceeds the preset rate of change threshold, it indicates that the equivalent impedance of the cathode is decreasing rapidly and the degree of decrease exceeds the normal fluctuation range, which is determined to be a sudden load drop event at the moment of arc ignition. At this time, the feedforward compensator is activated, and the corresponding feedforward compensation amount is calculated according to the amplitude of the impedance change rate and the pre-stored compensation amount amplitude mapping relationship.

[0088] As an example and not a limitation, the magnitude mapping relationship of the compensation can be a linear mapping: ΔD_ff = K_ff × |d Z / d t |, where ΔD_ff is the feedforward compensation amount, K_ff is the compensation amount amplitude mapping coefficient, |d Z / d t | represents the absolute value of the impedance change rate; piecewise nonlinear mapping can also be used to adapt to compensation requirements under different impedance change rates.

[0089] It is worth noting that the feedforward compensation amount does not immediately return to zero after a step transition, but gradually decays to zero as the amplitude of the impedance change rate decreases. This decay process is controlled by the aforementioned compensation decay time constant, and can typically adopt a first-order exponential decay form: ΔD_ff(t) = ΔD_ff(0) × exp (-t / τ) Where τ is the compensation decay time constant, t is the decay time, and ΔD_ff(0) is the initial feedforward compensation amount. Through the above decay mechanism, the feedforward compensation amount provides sufficient and rapid compensation in the early stage of arc initiation, and then smoothly exits, avoiding new current disturbances caused by a sudden drop in compensation amount. Based on the finally determined feedforward compensation amount and combined with the current base PWM duty cycle, the feedforward PWM duty cycle is calculated.

[0090] During the specific execution of the feedback control path, the deviation between the actual output current value of the contact power supply and the preset target current value is used as the input quantity, based on the deployed feedback control loop, and is imported into the feedback control loop for PID calculation.

[0091] Specifically, the feedback control loop automatically selects the corresponding PID parameter set based on the current operating condition of the cathode state machine. For no-load operation, it uses the first proportional gain and the first integral gain; for arc-starting transition operation, it uses the second proportional gain and the second integral gain; and for steady-state discharge operation, it uses the third proportional gain and the third integral gain. The deviation is calculated using proportional-integral operations to obtain the feedback correction amount. This feedback correction amount is then algebraically superimposed or incrementally accumulated with the current base PWM duty cycle to determine the feedback PWM duty cycle. The feedback control loop continuously executes the above process with a fixed control cycle to achieve continuous correction of the current deviation.

[0092] Finally, the feedforward PWM duty cycle output by the above feedforward control path and the feedback PWM duty cycle output by the feedback control path are coordinated in timing to jointly regulate the constant current of the holding power supply.

[0093] Specifically, the feedforward PWM duty cycle and the feedback PWM duty cycle are superimposed to determine the first superimposed PWM duty cycle. The meaning of the timing coordination is that at the instant of arc initiation, the feedforward compensation amount rapidly rises to its peak value and begins to decay exponentially, while the feedback correction amount gradually increases due to the establishment process of the PID integral. The two form a mutually exclusive relationship in the time dimension, with the feedforward responsible for the rapid disturbance suppression in the early stage of arc initiation, and the feedback responsible for the subsequent fine steady-state adjustment.

[0094] Subsequently, the first superimposed PWM duty cycle is converted into a pulse width modulation (PWM) signal via a modulator to generate a corresponding drive signal, which is a high-low level sequence with a specific duty cycle. This drive signal is transmitted to the power switch driver of the contact power supply. After receiving the drive signal, the power switch performs high-frequency switching operations according to the level sequence, thereby regulating the output current and voltage of the contact power supply in real time.

[0095] Once the arc is initiated, the feedforward compensation gradually decreases to zero as the impedance change rate decreases. At this point, the superimposed PWM duty cycle equals the feedback PWM duty cycle, and the holding power supply is independently adjusted by the feedback control loop to maintain steady-state constant current until an external command shuts it off or a fault protection is triggered.

[0096] Furthermore, step S2 of this application includes:

[0097] The first superimposed PWM duty cycle is determined by the timing coordination of the feedforward PWM duty cycle and the feedback PWM duty cycle; the first superimposed PWM duty cycle is converted into a drive signal by modulation, wherein the drive signal is a level sequence; the power switch receives the drive signal and performs on / off operation adjustment to regulate the output current and voltage of the contact power supply, wherein after the arc is started, the feedforward compensation amount is smoothly decayed to zero, and the feedback control loop performs subsequent control adjustment.

[0098] Specifically, the timing coordination refers to combining the feedforward PWM duty cycle and the feedback PWM duty cycle according to a preset superposition rule. This superposition rule can be a direct addition or a weighted superposition, where the weighting coefficient is dynamically adjusted based on the current operating conditions and the rate of change of impedance. As an example, and not a limitation, at the instant of arc initiation, the feedforward PWM duty cycle has a dominant weight, while the feedback PWM duty cycle contributes less due to integral lag; as the feedforward compensation gradually decreases, the weight of the feedback PWM duty cycle relatively increases. Through the above timing coordination, it is ensured that the PWM control quantity can quickly respond to load changes during the arc initiation transient process, while also maintaining steady-state accuracy.

[0099] Subsequently, the first superimposed PWM duty cycle is converted into a pulse width modulation (PWM) signal via a modulator to generate a corresponding drive signal. Specifically, the modulator is a digital pulse width modulation (PWM) module, which converts the numerical value of the first superimposed PWM duty cycle into a time ratio signal with a corresponding duty cycle. This drive signal is a sequence of alternating high and low levels, wherein the ratio of the high level duration to the switching period is equal to the first superimposed PWM duty cycle.

[0100] As an example, when the switching frequency is set to 50kHz, the switching period is 20μs. If the first superimposed PWM duty cycle is 0.35, the drive signal will be high for 7μs and low for 13μs in each switching cycle. The amplitude of the level sequence is adapted to the drive voltage requirements of the power switch, typically 12V or 15V logic levels.

[0101] Subsequently, the aforementioned drive signal is transmitted to the power switch driver terminal of the contact power supply. After receiving the drive signal, the power switch performs a high-frequency on / off operation according to the level sequence, that is, the switch is turned on during the high level and turned off during the low level, thereby adjusting the charging and discharging time ratio of the energy storage element of the contact power supply and realizing real-time control of the output current and output voltage.

[0102] Specifically, in the initial stage after arc initiation, the first superimposed PWM duty cycle increases due to the feedforward compensation being superimposed on the feedback PWM duty cycle. This leads to a corresponding increase in the power switch's on-duty cycle, rapidly enhancing the power supply's output capability to compensate for the current drop caused by the sudden decrease in cathode impedance. As the arc initiation process completes, the cathode impedance stabilizes at a low resistance state, and the impedance change rate gradually decreases to zero. The feedforward compensation then smoothly decays to zero according to an exponential decay law. The first superimposed PWM duty cycle gradually returns to equal the feedback PWM duty cycle. Subsequently, the feedback control loop independently executes subsequent steady-state constant current regulation, continuously maintaining the actual current following the target current until an external shutdown command or fault protection signal triggers the state machine to exit the current operating stage.

[0103] The automatic smooth exit mechanism of the feedforward compensation amount avoids the secondary current disturbance caused by the sudden drop in compensation amount, and achieves a seamless transition from the arc initiation transient to the steady state.

[0104] Furthermore, the steps in this application also include:

[0105] If the instruction type of the heating power supply is to turn on, increase / decrease, or turn off, a transition curve from the real-time current value to the target current value is generated according to the built-in trajectory planning terminal. By decomposing the transition curve into multiple micro-step adjustment cycles, soft switching control without current step is performed, and a heating transition indicator is simultaneously fed back to the cathode state machine.

[0106] In this embodiment, in order to reduce the thermal shock to the cathode heating wire during the current switching process of the heating power supply, soft switching management is performed on the current command of the heating power supply.

[0107] Specifically, when the heating power supply receives an instruction of the type of turn-on, shift, or turn-off, it does not directly jump to the target current value. Instead, it calls upon a pre-stored trajectory planning module and, based on the difference between the current real-time current value and the target current value, combines preset transition time parameters and curve shape parameters to generate a smooth transition curve from the real-time current value to the target current value. This transition curve can be an S-curve, an exponential curve, or a polynomial curve, characterized by slopes of zero or approaching zero at the beginning and end, and a smooth slope change in the middle section, thereby eliminating the current step impact caused by sudden acceleration changes.

[0108] As an example rather than a limitation, when the heating power supply is increased from 5A to 10A, the trajectory planning end generates an S-shaped transition curve starting from 5A and ending at 10A. The transition time is set according to the thermal time constant of the cathode heating wire, typically from 100ms to 500ms.

[0109] Furthermore, the transition curve is decomposed into multiple consecutive micro-step adjustment cycles on the time axis. Each micro-step adjustment cycle corresponds to a small current increment or decrement, thereby performing soft switching control without current step.

[0110] Specifically, within each micro-step adjustment cycle, the heating power supply adjusts the current actual current value to the target intermediate value corresponding to that cycle, and continues to approach the next intermediate value until the commanded target current value is finally reached. The step size and cycle time of the micro-step adjustment cycle can be dynamically configured according to the accuracy requirements. The smaller the step size, the smoother the switching process, but the adjustment time will be correspondingly longer. Typically, the step size can be set to 1% to 5% of the rated current, and the cycle time can be set to 1ms to 10ms.

[0111] By using the aforementioned micro-step successive approximation method, the current trajectory is ensured to perfectly match the transition curve, without any current jumps throughout the process, thereby avoiding the adverse effects of thermal shock on the lifespan of the cathode heating wire.

[0112] During the aforementioned soft switching of heating current, the control unit of the heating power supply synchronously feeds back a heating transition flag to the cathode state machine. This flag is a status signal, which is set to an active state when the heating power supply is in the soft switching execution period, and set to an inactive state after the switching is completed and stabilized at the target current value.

[0113] When the cathode state machine receives the flag, it suspends the steady-state determination of the rate of change of heating current during the switching process to prevent the state machine from misjudging the thermal state of the cathode due to the continuous change of heating current during the transition.

[0114] Through the feedback mechanism of the above-mentioned heating transition marker, the coordinated avoidance between the soft switching process of the heating power supply and the logic judgment of the cathode state machine is realized, ensuring that the state machine only performs state judgment when the heating current is stable, thereby improving the system's ability to resist misjudgment during the dynamic adjustment of current.

[0115] The Hall effect actuator holding and heating constant current power supply control method provided in this application has the following technical effects:

[0116] 1. By combining the rate of change of heating current to determine the cathode thermal state and high-frequency small-signal identification of the cathode equivalent impedance, a dual-dimensional judgment can accurately distinguish between two key operating conditions: emission preparation and arc initiation. This avoids misjudgment based on a single parameter and allows for early prediction of the cathode's electron emission capability and arc initiation timing. The cathode operation is divided into four stages: preheating preparation, waiting for arc initiation, arc transition, and self-sustaining discharge. Each stage has independent entry and exit judgment conditions, and the automatic switching control logic relies on state events to adapt to the different electrical characteristics of the cathode throughout its entire life cycle from preheating to steady-state discharge.

[0117] 2. To address the strong disturbance caused by the sudden drop in cathode impedance at the moment of arc ignition, a feedforward compensation branch is constructed using the impedance change rate to output the compensation duty cycle in advance to offset the current surge. Combined with multi-group PID feedback closed-loop steady-state regulation for different operating conditions, this significantly reduces current overshoot and spikes during the arc ignition phase, minimizing cathode erosion and power device losses. Independent proportional and integral gain parameters are configured for no-load, arc transition, and steady-state discharge, overcoming the limitation of a single set of PID parameters in achieving both fast response and zero steady-state error. This results in stronger stability of the constant current control under all operating conditions. After arc ignition, the feedforward compensation value decays to zero with the impedance change rate, smoothly transitioning to pure PID closed-loop regulation. This avoids current fluctuations during the switching between feedforward and feedback control, maintaining current stability during the self-sustaining discharge phase.

[0118] 3. By planning the current trajectory and adjusting the micro-step cycle, the heating current is gradually increased and decreased, eliminating the current step impact during start-up, shutdown and gear switching, and reducing thermal fatigue damage to the heating wire; at the same time, the heating transition flag is pushed to the state machine to assist in joint judgment of the working condition.

[0119] Example 2, based on the same inventive concept as the Hall thruster holding and heating constant current power supply control method in the foregoing examples, such as... Figure 2 As shown, this application provides a Hall effect actuator holding and heating constant current power supply control device, wherein the device includes:

[0120] Status detection module 1: By detecting the heating current change rate of the heating power supply, the contact power supply is impedance identified based on the cathode equivalent impedance value, and the cathode status data is jointly determined. The cathode status data includes the launch preparation state and the arc initiation state.

[0121] Constant current control module 2: By dividing the cathode working state into preheating preparation, waiting for arc ignition, arc ignition transition, and self-sustaining discharge, a cathode state machine is deployed. Based on the cathode state data, the cathode state machine adopts a state machine event triggering method to make feedforward and feedback coordinated control decisions under state switching, and performs constant current regulation management of the contact power supply. Among them, entry conditions and exit conditions are defined for each working state stage.

[0122] Among them, the feedforward and feedback coordinated control decision-making includes:

[0123] Feedforward decision unit 21: Taking the impedance value change rate based on impedance identification as input, it calculates the feedforward PWM duty cycle based on the negative over-threshold according to the feedforward compensator;

[0124] Feedback Decision Unit 22: Taking the deviation between the actual current and the target current as input, it determines the feedback PWM duty cycle based on PID analysis under the feedback control loop.

[0125] Furthermore, the state detection module 1 is used to perform the following steps: According to a preset sampling rate, it collects the output current value of the heating power supply in real time and continuously calculates the current change rate. By judging the absolute value of the current change rate against a preset threshold, it determines the cathode state sensing result. Wherein, when the absolute value is less than the preset threshold, the cathode state sensing result indicates that the heating current has entered the steady-state region, the cathode thermal state tends to be balanced, and the temperature is determined to have reached the emission threshold. A high-frequency small signal is superimposed at the output end of the contact power supply. By detecting the amplitude attenuation and phase shift of the response signal, the equivalent impedance value of the cathode is calculated in real time as the impedance identification result of the contact end. A comprehensive judgment is made based on the cathode state sensing result and the impedance identification result to obtain the cathode state data.

[0126] Furthermore, the state detection module 1 is used to perform the following steps: if the cathode state sensing result is that the heating current is stable and the impedance identification result is that the impedance drops from the first high resistance state, it is determined to be in the launch preparation state, wherein the launch preparation state triggers the cathode state machine to proceed to the next stage; if the cathode state sensing result is that the heating current is stable and the impedance identification result is that the impedance drops sharply to the second low resistance state threshold, it is determined to be in the arc initiation state, wherein the arc initiation state triggers the constant current loop feedforward compensation.

[0127] Furthermore, the constant current control module 2 is used to perform the following steps: by dividing the cathode working state, a cathode state machine is established; if the cathode state data is in the launch preparation state, it is used as the first state machine event, and the arc ignition program is triggered to start the holding power supply according to the cathode state machine; if the cathode state data is in the arc ignition state, it is used as the second state machine event, and the constant current loop feedforward compensation is triggered according to the cathode state machine, and the ignition power supply is triggered to start synchronously.

[0128] Furthermore, the constant current control module 2 is used to perform the following steps: for the contact power supply, configure feedforward control parameters and deploy a feedforward compensator, wherein the feedforward control parameters include an impedance change rate threshold, a compensation amplitude mapping coefficient, and a compensation attenuation time constant; for the contact power supply, configure feedback PID parameters based on the power supply operating conditions, wherein the contact power supply operating conditions include no-load operating conditions, arc-starting transition operating conditions, and steady-state discharge operating conditions, wherein the no-load operating conditions adopt a first proportional gain and a first integral gain, the arc-starting transition operating conditions adopt a second proportional gain and a second integral gain, and the steady-state discharge operating conditions adopt a third proportional gain and a third integral gain; and deploy a feedback control loop according to the feedback PID parameters.

[0129] Furthermore, the constant current control module 2 is used to perform the following steps: if constant current loop feedforward compensation is triggered, the impedance value change rate is used as input to the feedforward compensator based on the impedance identification result; when the impedance value change rate negatively exceeds the preset change rate threshold, the feedforward compensation amount is calculated based on the amplitude of the impedance change rate, wherein the feedforward compensation amount gradually decays to zero as the amplitude of the impedance change rate decreases; the feedforward PWM duty cycle is determined based on the feedforward compensation amount.

[0130] Furthermore, the constant current control module 2 is used to perform the following steps: determining the feedback correction amount based on the deviation between the actual current and the target current according to the feedback control loop; determining the feedback PWM duty cycle based on the feedback correction amount; and adjusting the contact power supply with the timing coordination of the feedforward PWM duty cycle and the feedback PWM duty cycle.

[0131] Furthermore, the constant current control module 2 is used to perform the following steps: determining a first superimposed PWM duty cycle by coordinating the timing of the feedforward PWM duty cycle and the feedback PWM duty cycle; converting the first superimposed PWM duty cycle into a drive signal via modulation, wherein the drive signal is a level sequence; the power switch receives the drive signal and performs on / off operation adjustment to regulate the output current and voltage of the contact power supply, wherein after the arc is started, the feedforward compensation amount smoothly decays to zero, and the feedback control loop performs subsequent control adjustment.

[0132] Furthermore, the system is also used to perform the following steps: if the instruction type of the heating power supply is to turn on, increase / decrease or turn off, a transition curve from the real-time current value to the target current value is generated according to the built-in trajectory planning terminal; by decomposing the transition curve into multiple micro-step adjustment cycles, soft switching control without current step is performed, and a heating transition indicator is simultaneously fed back to the cathode state machine.

[0133] Through the foregoing detailed description of a Hall thruster holding and heating constant current power supply control method, those skilled in the art can clearly understand the Hall thruster holding and heating constant current power supply control method in this embodiment. As for the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and relevant parts can be referred to the method section description.

[0134] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for controlling a Hall effect actuator's contact and heating constant current power supply, characterized in that, The method includes: By detecting the rate of change of heating current of the heating power supply, impedance identification based on the cathode equivalent impedance value is performed on the holding power supply, and cathode state data is jointly determined. The cathode state data includes the launch preparation state and the arc initiation state. By dividing the cathode working state into preheating preparation, waiting for arc ignition, arc ignition transition, and self-sustaining discharge, a cathode state machine is deployed. Based on the cathode state data, the cathode state machine adopts a state machine event triggering method to make feedforward and feedback coordinated control decisions under state switching, and performs constant current regulation management of the contact power supply. The entry and exit conditions are defined for each working state stage. Among them, the feedforward and feedback coordinated control decision-making includes: Using the impedance value change rate based on impedance identification as input, the feedforward PWM duty cycle based on the negative over-threshold is calculated according to the feedforward compensator. Using the deviation between the actual current and the target current as input, the duty cycle of the feedback PWM is determined based on PID analysis under the feedback control loop.

2. The Hall thruster holding and heating constant current power supply control method as described in claim 1, characterized in that, Determine the cathode condition data, including: According to the preset sampling rate, the output current value of the heating power supply is collected in real time and the current change rate is continuously calculated. The cathode state sensing result is determined by judging the absolute value of the current change rate by a preset threshold. When the absolute value is less than the preset threshold, the cathode state sensing result indicates that the heating current has entered the steady state region, the cathode thermal state tends to be in equilibrium, and the temperature is determined to have reached the emission threshold. A high-frequency small signal is superimposed at the output of the contact power supply. By detecting the amplitude attenuation and phase shift of the response signal, the equivalent impedance value of the cathode is calculated in real time and used as the impedance identification result of the contact end. The cathode state data is obtained by comprehensively judging the cathode state sensing results and impedance identification results.

3. The Hall thruster holding and heating constant current power supply control method as described in claim 2, characterized in that, If the cathode state sensing result is that the heating current is stable and the impedance identification result is that it decreases from the first high resistance state, it is determined to be in the launch preparation state, wherein the launch preparation state triggers the cathode state machine to proceed to the next stage; If the cathode state sensing result is that the heating current is stable and the impedance identification result is that the impedance drops sharply to the second low resistance threshold, it is determined to be an arc initiation state, wherein the arc initiation state triggers constant current loop feedforward compensation.

4. The Hall thruster holding and heating constant current power supply control method as described in claim 1, characterized in that, The cathode state machine employs a state machine event triggering method, including: A cathode state machine is established by dividing the cathode operating states; If the cathode state data is in the launch preparation state, it is treated as a first state machine event. According to the cathode state machine, the arc initiation program is triggered to start the contact power supply. If the cathode state data indicates an arc initiation state, it is treated as a second state machine event. Based on the cathode state machine, the constant current loop feedforward compensation is triggered, and the ignition power supply is started simultaneously.

5. The Hall thruster holding and heating constant current power supply control method as described in claim 2, characterized in that, Before making feedforward and feedback coordinated control decisions under state switching, the configuration of the feedforward compensator and feedback control loop includes: For the power supply, feedforward control parameters are configured and a feedforward compensator is deployed. The feedforward control parameters include an impedance change rate threshold, a compensation magnitude mapping coefficient, and a compensation attenuation time constant. For the power supply, feedback PID parameters based on the power supply operating conditions are configured. The operating conditions of the power supply include no-load condition, arcing transition condition and steady-state discharge condition. The no-load condition adopts a first proportional gain and a first integral gain, the arcing transition condition adopts a second proportional gain and a second integral gain, and the steady-state discharge condition adopts a third proportional gain and a third integral gain. Based on the feedback PID parameters, deploy a feedback control loop.

6. The Hall thruster holding and heating constant current power supply control method as described in claim 5, characterized in that, Making coordinated control decisions between feedforward and feedback during state transitions includes: If the constant current loop feedforward compensation is triggered, the impedance value change rate is used as input to the feedforward compensator based on the impedance identification result. When the rate of change of impedance exceeds the preset rate of change threshold in the negative direction, the feedforward compensation amount is calculated based on the magnitude of the rate of change of impedance. The feedforward compensation amount gradually decays to zero as the magnitude of the rate of change of impedance decreases. The feedforward PWM duty cycle is determined based on the feedforward compensation amount.

7. The Hall thruster holding and heating constant current power supply control method as described in claim 6, characterized in that, Making coordinated control decisions between feedforward and feedback during state transitions includes: Based on the feedback control loop, the feedback correction amount is determined using the deviation between the actual current and the target current as input. The feedback PWM duty cycle is determined based on the feedback correction amount. The constant current regulation of the contact power supply is achieved by coordinating the timing of the feedforward PWM duty cycle and the feedback PWM duty cycle.

8. The Hall thruster holding and heating constant current power supply control method as described in claim 7, characterized in that, The first superimposed PWM duty cycle is determined by coordinating the timing of the feedforward PWM duty cycle and the feedback PWM duty cycle. The first superimposed PWM duty cycle is modulated and converted into a drive signal, wherein the drive signal is a level sequence; The power switch receives the drive signal and performs on / off operation adjustment to regulate the output current and voltage of the contact power supply. After the arc is started, the feedforward compensation amount is smoothly decayed to zero, and the feedback control loop performs subsequent control adjustment.

9. The Hall thruster holding and heating constant current power supply control method as described in claim 1, characterized in that, The method further includes: If the instruction type of the heating power supply is to turn on, increase / decrease or turn off, a transition curve from the real-time current value to the target current value is generated according to the built-in trajectory planning terminal. By decomposing the transition curve into multiple micro-step adjustment cycles, soft switching control is performed under current-free step conditions, and a heating transition indicator is simultaneously fed back to the cathode state machine.

10. A Hall effect actuator holding and heating constant current power supply control device, characterized in that, The apparatus for performing a Hall effect actuator holding and heating constant current power supply control method as described in any one of claims 1-9 includes: Status detection module: By detecting the heating current change rate of the heating power supply and performing impedance identification of the holding power supply based on the cathode equivalent impedance value, the cathode status data is jointly determined. The cathode status data includes the launch preparation state and the arc initiation state. Constant current control module: By dividing the cathode working state into preheating preparation, waiting for arc ignition, arc ignition transition, and self-sustaining discharge, a cathode state machine is deployed. Based on the cathode state data, the cathode state machine adopts a state machine event triggering method to make feedforward and feedback coordinated control decisions under state switching, and performs constant current regulation management of the contact power supply. Among them, entry conditions and exit conditions are defined for each working state stage. Among them, the feedforward and feedback coordinated control decision-making includes: Feedforward decision unit: Taking the impedance value change rate based on impedance identification as input, it calculates the feedforward PWM duty cycle based on the negative over-threshold according to the feedforward compensator; Feedback decision unit: Taking the deviation between the actual current and the target current as input, it determines the feedback PWM duty cycle based on PID analysis under the feedback control loop.

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