Electric propulsion xenon consumption evaluation method based on pressure and current fusion integral

Abstract

An electric propulsion xenon consumption evaluation method based on pressure and current fusion integration comprises the steps that the output pressure of a bang-bang valve electronic pressure reduction system and the heating current of a thermal throttler serve as input parameters, the xenon flow is calculated, real-time integration is carried out, the xenon consumption of electric propulsion ignition is obtained, use is convenient, the cost is low, and the electric propulsion xenon consumption evaluation method is suitable for popularization and application. The method can be used on a spacecraft provided with a bang-bang valve and a thermal throttler electric propulsion system, and ground calculation can be achieved under the condition that the calculation burden on the spacecraft is not increased.

Description

Technical Field

[0001] The invention relates to an electric propulsion xenon consumption evaluation method based on pressure and current fusion integration, and belongs to the field of aerospace propulsion technology design. Background Art

[0002] The Hall electric propulsion system consists of a pressure regulating module, a flow control module, a Hall thruster, and a power processing unit. The pressure regulating module is an electronic decompression system that provides inlet pressure for the flow control module; the flow control module is a flow control system that performs closed-loop control with the anode current of the Hall thruster as the target value. There is no flow sensor in the Hall electric propulsion system, so the xenon flow cannot be directly measured, and the electric propulsion consumption cannot be directly evaluated. During the ignition of the electric propulsion system, the electric propulsion thrust can be calculated from the anode current and anode voltage. If the xenon flow cannot be evaluated, the specific impulse of the electric propulsion cannot be calculated, which directly affects the evaluation of the life of the entire satellite. Summary of the invention

[0003] The technical problem solved by the present invention is: in view of the problem that the traditional Hall electric propulsion system in the current prior art cannot directly monitor the input xenon gas flow, a method for evaluating the electric propulsion xenon gas consumption based on pressure and current fusion integration is proposed.

[0004] The present invention solves the above technical problems by the following technical solutions:

[0005] A method for evaluating xenon consumption in electric propulsion based on pressure and current fusion integration includes:

[0006] Adjust the composition of the electric propulsion system, and preset a pressure regulating module and a flow control module in the electric propulsion system;

[0007] Carry out flow calibration on the flow control module;

[0008] Fitting is performed based on the flow calibration results to determine the xenon gas flow calculation method;

[0009] When the electric propulsion system is ignited, the upstream input gas is decompressed by the pressure regulating module to the target pressure value required by the downstream input flow control module for decompression fluctuation processing;

[0010] The xenon consumption of the electric propulsion system is calculated in real time based on the parameters collected by the pressure regulation module and the flow control module.

[0011] The electric propulsion system is a Hall electric propulsion system, including a pressure regulating module, a flow control module, a Hall thruster, and a power processing unit. The pressure regulating module adopts a bang-bang valve after adjustment to provide input pressure for the flow control module; the flow control module adopts a thermal throttle to perform closed-loop control with the anode current of the Hall thruster as the target value, and the thermal throttle is used to change the flow resistance of the input xenon gas; the power processing unit supplies power to the Hall thruster, and the Hall thruster generates thrust according to the xenon gas flow and input pressure.

[0012] There is high-pressure xenon gas upstream of the bang-bang valve. The bang-bang valve and the pressure sensor form an electronic decompression system. After the xenon gas input to the bang-bang valve is decompressed, the output pressure of the xenon gas is controlled to be within the fluctuation range of the target pressure value at the inlet of the thermal throttle. The fluctuation range is determined according to the selected type and parameters of the thermal throttle.

[0013] The thermal throttle adopts heating valve body temperature to change the xenon gas flow resistance in the valve body and change the xenon gas flow rate;

[0014] Under the same heating current, the xenon input pressure of the thermal throttle valve is positively correlated with the xenon flow rate. The electric propulsion system achieves closed-loop control of the input xenon flow rate through the thermal throttle and bang-bang valve.

[0015] The method for calibrating the flow rate of the flow control module is:

[0016] Taking the xenon gas pressure at the inlet of the thermal throttle and the heating current of the thermal throttle as variables, the output pressure range and heating current working conditions of the pressure regulating module are designed;

[0017] Determine the working condition calibration matrix according to the output pressure range of the pressure regulating module and the heating current working condition;

[0018] According to the working condition calibration matrix, the flow calibration is performed on the selected different thermal throttles to obtain the flow calibration results including the xenon input pressure, heating current and xenon flow data of the thermal throttle.

[0019] The pressure conditions include a target pressure value and a pressure condition where the target pressure value fluctuates within a preset pressure range;

[0020] The specific working condition of the heating current is designed according to the valve body selection of the flow control module, and the current working condition fluctuates within the preset range of the basic current working condition;

[0021] The calibration matrix is ​​a kxn calibration matrix consisting of n pressure conditions and k current conditions. The xenon gas flow calculation method is determined by polynomial smooth surface fitting based on the flow calibration result:

[0022] q=f(P,I)

[0023] f(P,I)=k 00 +k 10 *P+k 01 *I+k 20 *P 2 +k 11 *P*I+k 02 *I 2 +k 30 *P 3 +k 21 *P 2 *I+

[0024] k 12 *P*I 2 +k 03 *I 3 +k 40 *P 4 +k 31 *P 3 *I+k 22 *P 2 *I 2 +k 13 *P*I 3 +k 04 *I 4

[0025] Where P is the xenon gas input pressure of the thermal throttle, I is the heating current of the thermal throttle, q is the xenon gas flow rate, k 00 , k 10 , k 01 , k 20 , k 11 , k 02 , k 30 , k 21 , k 12 , k 03 , k 40 , k 31 , k 22 , k 13 , k 04 are the polynomial fitting coefficients.

[0026] After the electric propulsion system is ignited, the bang-bang valve electronic pressure reduction system controls the xenon pressure input to the hot throttle according to the preset target pressure fluctuation range, and collects the real-time telemetry pressure value P i ; Collect the heating current I of the thermal throttle i , calculate the xenon consumption of the electric propulsion system at the current moment according to the xenon consumption calculation formula of the electric propulsion system.

[0027] The xenon consumption calculation formula of the electric propulsion system is:

[0028] m=∑f(P i,I i )Δt i

[0029] Where Δt is the telemetry time difference of each frame, and m is the xenon consumption.

[0030] The electric propulsion system implements flow control of input xenon gas according to the pressure regulation module and the flow control module, and obtains the xenon gas consumption by integrating the real-time telemetry pressure value and the heating current value. The input xenon gas passes through a preset xenon gas flow model to collect the required pressure regulation parameters and flow control parameters, and the collected parameters are used to cover all on-orbit operating conditions.

[0031] The advantages of the present invention compared with the prior art are:

[0032] (1) The present invention provides an electric propulsion xenon consumption evaluation method based on pressure and current fusion integration. Based on actual needs, without adding a flow sensor to the Hall electric propulsion system, an electric propulsion xenon consumption evaluation method based on pressure and current fusion integration is proposed. The output pressure of the bang-bang valve electronic decompression system and the heating current of the thermal throttle are used as input parameters to calculate the xenon flow rate, and the xenon consumption of the electric propulsion ignition is obtained by real-time integration.

[0033] (2) The present invention does not need to increase the configuration of flow sensors. It only needs to integrate the telemetry pressure value and the heating current to obtain the xenon consumption. It adopts an accurate xenon flow model and obtains it through matrix parameter calibration of pressure and heating current, covering the on-orbit working conditions. It is more convenient to use and can be used on spacecraft equipped with bang-bang valves and thermal throttle electric propulsion systems. There is no need to increase the computational burden on the spacecraft, and ground calculations can be performed directly. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A flow control block diagram of the Hall electric propulsion system provided for the invention; DETAILED DESCRIPTION

[0035] A method for evaluating xenon consumption in electric propulsion based on pressure and current fusion integration is proposed. The output pressure of the bang-bang valve electronic decompression system and the heating current of the thermal throttle are used as input parameters to calculate the xenon flow rate, and the real-time integration is performed to obtain the xenon consumption of electric propulsion ignition. The method is easy to use and can be used on spacecraft equipped with bang-bang valve and thermal throttle electric propulsion systems, and can realize ground calculation without increasing the calculation burden on the spacecraft.

[0036] The xenon consumption evaluation method for electric propulsion based on pressure and current fusion integration includes the following steps:

[0037] Adjust the composition of the electric propulsion system, and preset a pressure regulating module and a flow control module in the electric propulsion system;

[0038] Carry out flow calibration on the flow control module;

[0039] Fitting is performed based on the flow calibration results to determine the xenon gas flow calculation method;

[0040] When the electric propulsion system is ignited, the upstream input gas is decompressed by the pressure regulating module to the target pressure value required by the downstream input for decompression fluctuation processing;

[0041] The xenon consumption of the electric propulsion system is calculated in real time based on the parameters collected by the pressure regulation module and the flow control module.

[0042] The electric propulsion system is a Hall electric propulsion system, including a pressure regulation module, a flow control module, a Hall thruster, and a power processing unit. The pressure regulation module adopts a bang-bang valve after adjustment to provide input pressure for the flow control module; the flow control module adopts a thermal throttle and performs closed-loop control with the anode current of the Hall thruster as the target value. The thermal throttle is used to change the flow resistance of the input xenon gas; the power processing unit supplies power to the Hall thruster, and the Hall thruster generates thrust according to the xenon gas flow and input pressure.

[0043] After the bang-bang valve decompresses the input xenon gas, the xenon gas input pressure is controlled to be within a fluctuation range of the target pressure value at the inlet of the thermal throttle, and the fluctuation range is determined according to the selected type and parameters of the thermal throttle.

[0044] The thermal throttle uses the temperature of the heated valve body to change the xenon gas flow resistance and thus change the xenon gas flow rate;

[0045] Under the same heating current, the xenon input pressure is positively correlated with the xenon flow rate. The electric propulsion system achieves closed-loop control of the input xenon flow rate through a thermal throttle and a bang-bang valve.

[0046] The method for calibrating the flow rate of the flow control module is:

[0047] Taking the xenon gas pressure at the inlet of the thermal throttle and the heating current of the thermal throttle as variables, the output pressure range and heating current working conditions of the pressure regulating module are designed;

[0048] Determine the working condition calibration matrix according to the output pressure range of the pressure regulating module and the heating current working condition;

[0049] According to the working condition calibration matrix, the flow calibration is performed on the selected different thermal throttles to obtain the flow calibration results including xenon gas input pressure, heating current and xenon gas flow data.

[0050] The pressure conditions include a target pressure value and a pressure condition where the target pressure value fluctuates within a preset pressure range;

[0051] The specific working condition of the heating current is designed according to the valve body selection of the flow control module, and the current working condition fluctuates within the preset range of the basic current working condition;

[0052] The calibration matrix is ​​a kxn calibration matrix consisting of n pressure operating conditions and k current operating conditions.

[0053] The xenon gas flow calculation method is determined by polynomial smooth surface fitting based on the flow calibration results:

[0054] q=f(P,I)

[0055] f(P,I)=k 00 +k 10 *P+k 01 *I+k 20 *P 2 +k 11 *P*I+k 02 *I 2 +k 30 *P 3 +k 21 *P 2 *I+

[0056] k 12 *P*I 2 +k 03 *I 3 +k 40 *P 4 +k 31 *P 3 *I+k 22 *P 2 *I 2 +k 13 *P*I 3 +k 04 *I 4

[0057] Where P is the xenon gas input pressure of the thermal throttle, I is the heating current of the thermal throttle, q is the xenon gas flow rate, k 00 , k 10 , k 01 , k 20 , k 11 , k 02 , k 30 , k 21 , k 12 , k 03 , k 40 , k 31 , k 22 , k 13, k 04 are the polynomial fitting coefficients.

[0058] After the electric propulsion system is ignited, the bang-bang valve controls the input xenon pressure according to the preset target pressure fluctuation range and collects the real-time telemetry pressure value P i ; Collect the heating current I of the thermal throttle i , calculate the xenon consumption of the electric propulsion system at the current moment according to the xenon consumption calculation formula of the electric propulsion system.

[0059] The xenon consumption calculation formula of the electric propulsion system is:

[0060] m=∑f(P i ,I i )Δt i

[0061] Where Δt is the telemetry time difference of each frame, and m is the xenon consumption.

[0062] The electric propulsion system implements flow control of input xenon gas based on the pressure regulation module and the flow control module, and obtains the xenon consumption by integrating the real-time telemetry pressure value and the heating current value. The input xenon gas passes through a preset xenon flow model to collect the required pressure regulation parameters and flow control parameters. The collected parameters are used to cover all on-orbit operating conditions.

[0063] Specifically, Figure 1 As shown, the electric propulsion system uses a bang-bang valve electronic decompression system and a thermal throttle combination to achieve fine control of the flow rate. Among them, the bang-bang valve electronic decompression system reduces the upstream high pressure to the target pressure value at the downstream thermal throttle inlet. Due to the switch control characteristics of the bang-bang, the pressure output presents a sawtooth bang-bang shape, fluctuating within a certain range of positive and negative target pressure values; the thermal throttle uses a heated valve body temperature to change the xenon gas flow resistance, thereby changing the xenon flow rate. Under the same heating current of the throttle, the xenon flow rate is different when the inlet pressure is different. Therefore, the xenon flow rate of the electric propulsion system based on the bang-bang valve and the thermal throttle is correlated with the bang-bang valve output pressure and the thermal throttle heating current, and the flow control of the electric propulsion system is achieved based on the bang-bang valve and the thermal throttle.

[0064] When calibrating the flow rate of the thermal throttle, the xenon pressure at the inlet of the thermal throttle and the heating current of the thermal throttle are used as variables, and the working conditions covering the output pressure range and heating current of the bang-bang electronic decompression system are designed to form a working condition calibration matrix. For example, the pressure is divided into 7 pressure conditions, including target pressure value, target pressure value*(1±2%), target pressure value*(1±5%), and target pressure value*(1±7%), and the heating current is divided into 5 working conditions, forming a 7x5 calibration matrix. The flow rate of the thermal throttle is calibrated for each combination of pressure and heating current.

[0065] The electric propulsion system does not need to add flow sensor configuration. It only needs to integrate the telemetry pressure value and heating current to obtain the xenon consumption. The xenon flow model is accurate and is obtained through matrix parameter calibration of pressure and heating current, covering on-orbit conditions.

[0066] The following is further described in conjunction with the accompanying drawings and preferred embodiments of the specification:

[0067] In the current embodiment, an example of an electric propulsion xenon consumption estimation method based on pressure and current fusion integration is as follows:

[0068] Taking the xenon pressure P at the inlet of the thermal throttle and the heating current I of the thermal throttle as variables, the working conditions covering the output pressure range and heating current of the bang-bang electronic decompression system are designed to form a working condition calibration matrix. For example, the pressure is divided into 7 pressure conditions, including the target pressure value, target pressure value*(1±2%), target pressure value*(1±5%), and target pressure value*(1±7%), and the heating current is divided into 5 conditions, forming a 7x5 calibration matrix M;

[0069] For each pressure and thermal throttle heating current combination M in the calibration matrix M ij (i is 1 to 7, j is 1 to 5) to calibrate the xenon gas flow rate;

[0070] The polynomial smooth surface fitting is used to obtain the xenon flow calculation formula. When the electric propulsion is ignited, the telemetry pressure value P is i Pressure measurement, thermal throttle heating current I i Perform an integral calculation to obtain the xenon consumption of the electric propulsion system.

[0071] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

[0072] The contents not described in detail in the specification of the present invention belong to the common knowledge of those skilled in the art.

Claims

1. A method for evaluating xenon consumption in electric propulsion based on pressure and current fusion integration, characterized in that include: Preset a pressure regulating module and a flow control module in the electric propulsion system; Perform flow calibration on the flow control module and obtain the flow calibration result; Fitting is performed based on the flow calibration results to determine the xenon gas flow calculation method; When the electric propulsion system is ignited, the upstream input gas is decompressed by the pressure regulating module to the target pressure value required by the downstream input flow control module for decompression fluctuation processing; According to the parameters collected by the pressure regulation module and the flow control module, the xenon consumption of the electric propulsion system is calculated in real time through the xenon flow calculation method.

2. The electric propulsion xenon consumption evaluation method based on pressure and current fusion integration according to claim 1 is characterized by: The electric propulsion system is a Hall electric propulsion system, including a pressure regulating module, a flow control module, a Hall thruster, a power processing unit, and a thermal throttle. The pressure regulating module adopts a bang-bang valve after adjustment to provide input pressure for the flow control module; the flow control module adopts a thermal throttle to perform closed-loop control with the anode current of the Hall thruster as the target value, and the thermal throttle is used to change the input xenon gas flow resistance; The power processing unit supplies power to the Hall thrusters, which generate thrust based on the xenon gas flow and input pressure.

3. The electric propulsion xenon consumption evaluation method based on pressure and current fusion integration according to claim 2 is characterized by: There is high-pressure xenon gas upstream of the bang-bang valve. The bang-bang valve and the pressure sensor form an electronic decompression system. After the xenon gas input to the bang-bang valve is decompressed, the output pressure of the xenon gas is controlled to be within the fluctuation range of the target pressure value at the inlet of the thermal throttle. The fluctuation range is determined according to the selected type and parameters of the thermal throttle.

4. The electric propulsion xenon consumption evaluation method based on pressure and current fusion integration according to claim 2 is characterized by: The thermal throttle adopts heating valve body temperature to change the xenon gas flow resistance in the valve body and change the xenon gas flow rate; Under the same heating current, the xenon input pressure in the thermal throttle is positively correlated with the xenon flow rate. The electric propulsion system achieves closed-loop control of the input xenon flow rate through the thermal throttle and bang-bang valve.

5. The electric propulsion xenon consumption evaluation method based on pressure and current fusion integration according to claim 2 is characterized by: The method for calibrating the flow rate of the flow control module is: Taking the xenon gas pressure at the inlet of the thermal throttle and the heating current of the thermal throttle as variables, the output pressure range and heating current working conditions of the pressure regulating module are designed; Determine the working condition calibration matrix according to the output pressure range of the pressure regulating module and the heating current working condition; According to the working condition calibration matrix, the flow calibration is performed on the selected different thermal throttles to obtain the flow calibration results including the xenon input pressure, heating current and xenon flow data of the thermal throttle.

6. The electric propulsion xenon consumption assessment method based on pressure and current fusion integration according to claim 1 is characterized by: The pressure conditions include a target pressure value and a pressure condition where the target pressure value fluctuates within a preset pressure range; The specific working condition of the heating current is designed according to the valve body selection of the flow control module, and the current working condition fluctuates within the preset range of the basic current working condition; The calibration matrix is ​​a kxn calibration matrix consisting of n pressure operating conditions and k current operating conditions.

7. The electric propulsion xenon consumption assessment method based on pressure and current fusion integration according to claim 6 is characterized by: The xenon gas flow calculation method is determined by polynomial smooth surface fitting based on the flow calibration result: q=f(P,I) f(P,I)=k 00 +k 10 *P+k 01 *I+k 20 *P 2 +k 11 *P*I+k 02 *I 2 +k 30 *P 3 +k 21 *P 2 *I+ k 12 *P*I 2 +k 03 *I 3 +k 40 *P 4 +k 31 *P 3 *I+k 22 *P 2 *I 2 +k 13 *P*I 3 +k 04 *I 4 Where P is the xenon gas input pressure of the thermal throttle, I is the heating current of the thermal throttle, q is the xenon gas flow rate, k 00 , k 10 , k 01 , k 20 , k 11 , k 02 , k 30 , k 21 , k 12 , k 03 , k 40 , k 31 , k 22 , k 13 , k 04 are the polynomial fitting coefficients.

8. The electric propulsion xenon consumption evaluation method based on pressure and current fusion integration according to claim 2 is characterized by: After the electric propulsion system is ignited, the bang-bang valve electronic pressure reduction system controls the xenon pressure input to the hot throttle according to the preset target pressure fluctuation range, and collects the real-time telemetry pressure value P i ; Collect the heating current I of the thermal throttle i , calculate the xenon consumption of the electric propulsion system at the current moment according to the xenon consumption calculation formula of the electric propulsion system.

9. The electric propulsion xenon consumption assessment method based on pressure and current fusion integration according to claim 8, characterized in that: The xenon consumption calculation formula of the electric propulsion system is: m=∑f(P i ,I i )Δt i Where Δt is the telemetry time difference of each frame, and m is the xenon consumption.

10. The electric propulsion xenon consumption assessment method based on pressure and current fusion integration according to claim 8, characterized in that: The electric propulsion system implements flow control of input xenon gas according to the pressure regulating module and the flow control module, and obtains xenon gas consumption by integrating and calculating the real-time telemetry pressure value and the heating current value; Input xenon gas passes through the preset xenon gas flow model to collect the required pressure regulation parameters and flow control parameters. The collected parameters are used to cover all on-orbit operating conditions.

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