Fixed-point propellant residual quantity initial value determination method for high-orbit satellite plate type storage tank

Abstract

The application relates to a fixed-point propellant residual quantity initial value determination method for a high-orbit satellite plate type storage tank and belongs to the technical field of spacecraft propulsion systems. The liquid level height range [S2, S1] of propellant with a residual quantity in the range of [M1, M2] in a plate type storage tank is calculated under a satellite orbit control bottoming state; a measuring unit is pasted on the outer surface of the plate type storage tank; the propellant mass corresponding to the bottoming state of the propellant in the storage tank at the position of each temperature measuring point is determined; a heating belt is turned on, and the temperature data of each temperature measuring point is collected; the heating belt is turned off; the temperature change rate of each temperature measuring point is calculated; the residual quantity initial values M a0 and M b0 of the propellant in the plate type storage tank are respectively calculated; M a0 and M b0 are compared, and the final evaluation of the satellite fixed-point propellant residual quantity initial value in the storage tank is obtained; the application can be mutually verified with a traditional method on one hand, and the evaluation error can be reduced to within 15 kg compared with the traditional BK method, so that the evaluation precision of the satellite fixed-point propellant residual quantity initial value can be obviously improved.

Description

Technical Field

[0001] This invention belongs to the field of spacecraft propulsion system technology, and relates to a method for determining the initial value of the remaining propellant in a plate-type propellant tank for high-orbit satellites. Background Technology

[0002] In spacecraft propulsion systems, plate-type propellant tanks are a replacement for traditional mesh-type tanks. Compared to traditional mesh-type tanks, plate-type tanks have advantages such as simple structure, light weight, and good manufacturability. Therefore, in recent years, spacecraft, especially high-orbit communication satellites, have widely adopted plate-type tanks to replace traditional mesh-type tanks both domestically and internationally. However, while using plate-type tanks saves weight, it also sacrifices the ability to assess the propellant state inside the tank using the bubble bursting phenomenon of mesh-type tank screens.

[0003] Currently, high-orbit satellites generally use the traditional Black-Kruger method to calculate propellant consumption during orbit change. After the satellite reaches its target orbit and is positioned at its designated point, the remaining propellant is obtained by subtracting the propellant consumed during the orbit change from the initial propellant load. This remaining propellant is then used as the initial value for the satellite's remaining propellant for subsequent on-orbit operations, i.e., the initial value for the remaining propellant at the designated point. This method is affected by many factors, and the calculation error exceeds 1% of the propellant consumed during the orbit change (approximately 30 kg). Summary of the Invention

[0004] The technical problem solved by this invention is to overcome the shortcomings of the prior art and propose a method for determining the initial value of the remaining propellant in the plate-type tank of high-orbit satellites. On the one hand, it can be mutually verified with the traditional method. On the other hand, its evaluation error can be reduced to less than 15 kg compared with the traditional BK method, which can significantly improve the evaluation accuracy of the initial value of the remaining propellant in satellites.

[0005] The solution of the present invention is: Methods for determining the initial value of remaining propellant in plate-type propellant tanks of high-orbit satellites include: Based on the propellant budget of the satellite design, the range of remaining propellant in the tank at the end of the satellite orbit change is [M2, M1]; using the liquid volume calculation formula, the range of liquid level in the plate tank [S2, S1] of the remaining propellant in the range of [M1, M2] under the satellite orbit control bottoming state is calculated. A measuring unit is attached to the outer surface of the plate-type storage tank; the measuring unit includes a set of temperature measuring points and a heating strip. Based on the geometric dimensions of the plate tank under working pressure and the density of the propellant at room temperature, determine the propellant mass M in the tank at each temperature measurement point location under the condition of propellant settling to the bottom. C+N M C+N …M C+1 M C M C-1 …MC-N+1 M C-N ; Turn on the heating belt and collect temperature data at each measuring point simultaneously; Turn off the heating element and stop collecting temperature data; Based on the temperature data from each temperature measurement point, calculate the temperature change rate ΔT at each temperature measurement point. C+N ..., ΔT C+1 ΔT C ΔT C-1 ..., ΔT C-N ; Two calculation methods were used to calculate the initial value M of the remaining propellant in the plate-type tank, based on the temperature change rate at each temperature measurement point. a0 and M b0 ; Compare M a0 and M b0 The final estimated initial value of the remaining propellant in the propellant tank at the time of satellite positioning.

[0006] In the above-described method for determining the initial value of remaining propellant in a plate-type propellant tank for high-orbit satellites, the liquid level height is the distance between the propellant liquid level and the center spherical surface at the bottom of the tank.

[0007] In the above-mentioned method for determining the initial value of the remaining propellant in a plate-type tank for high-orbit satellites, the outer surface of the plate-type tank is uniformly distributed with guide strips along the circumference; the measuring unit is attached between any two adjacent guide strips; the central temperature measuring point of the measuring unit is located at (S1+S2) / 2.

[0008] In the above-mentioned method for determining the initial value of the remaining propellant in the plate-type tank of a high-orbit satellite, the number of temperature measuring points is set to 2N+1; the 2N+1 temperature measuring points are evenly spaced along the vertical direction, and their serial numbers from top to bottom are C+N, C+N+1, ..., C+1, C, C-1, ..., C-N+1, CN; the distance L1 between two adjacent temperature measuring points is 3-5mm; the coverage area L2 of the 2N+1 temperature measuring points is not less than S1-S2; and the distance L3 between the heating belt and each temperature measuring point is 10-20mm.

[0009] In the above-mentioned method for determining the initial value of the remaining propellant in the plate-type propellant tank of a high-orbit satellite, the heating belt is activated 3 minutes before the satellite's last orbit change ignition ends.

[0010] In the above-mentioned method for determining the initial value of the remaining propellant in the plate-type propellant tank of a high-orbit satellite, the heating belt is turned off 2 minutes after the satellite's last orbital maneuver ignition.

[0011] Based on the aforementioned method for determining the initial value of remaining propellant in plate-type tanks for high-orbit satellites, the initial value M of the remaining propellant in the plate-type tank is calculated. a0 The method is as follows: Compare the temperature change rate of adjacent temperature measurement points from 0 to 3 minutes. When three consecutive temperature change rates at a certain adjacent temperature measurement point satisfy ΔT C+N >1.5×ΔT C+N-1 At this time, it is assumed that the propellant level in the tank is between temperature measuring points C+a and C+a-1 when the heating belt is activated 3 minutes before the end of the orbital change ignition; at this time, the remaining propellant in the tank is (M C+a +M C+a-1 ) / 2; then the initial value of the remaining propellant in the tank is M. a0 for: M a0 =(M C+a +M C+a-1 ) / 2-M 3min -M 捕获 In the formula, M 3min The BK method was used to calculate the propellant charge consumed by the propellant tank during the last 3 minutes of satellite orbit control. M 捕获 The BK method was used to calculate the propellant charge consumed by the satellite during its acquisition and positioning after the orbit change was completed. When there are no adjacent temperature measurement points, there are three consecutive temperature change rates that satisfy ΔT C+N >1.5×ΔT C+N-1 At that time, the coefficient was reduced from 1.5 to 1.4, and the initial value M of the remaining propellant in the plate tank was calculated. a0 This continues until the initial value M of the remaining propellant in the plate tank is calculated. a0 .

[0012] Based on the aforementioned method for determining the initial value of remaining propellant in plate-type tanks for high-orbit satellites, the initial value M of the remaining propellant in the plate-type tank is calculated. b0 The method is as follows: Compare the rate of temperature change at each temperature measurement point over 3-5 minutes; When there are temperature measurement points that all satisfy ΔT within 3-5 minutes C+b >0, and the rate of temperature change ΔT at temperature measurement points above this point. C+b-1 …ΔT C+N If three or more consecutive data acquisition points satisfy <0, then it is considered that at the end of the satellite's orbit change ignition, the propellant level in the tank is between measurement points C+b and C+b-1, and the remaining propellant in the tank at this time is (M C+b +M C+b-1 ) / 2; then the initial value of the remaining propellant in the tank is M. b0 for: M b0 =(M C+b +M C+b-1 ) / 2-M 捕获 In the formula, M 捕获 The BK method was used to calculate the propellant charge consumed by the satellite during its acquisition and positioning after the orbit change was completed. When there is no temperature measurement point, ΔT is satisfied for 3-5 minutes. C+b >0, and the rate of temperature change ΔT at temperature measurement points above this point. C+b-1 …ΔT C+N If three or more consecutive data collection points satisfy the condition < 0, then the test condition is not met, and M does not exist. b0 .

[0013] In the above-mentioned method for determining the initial value of remaining propellant in plate-type tanks for high-orbit satellites, when M is not present... b0 At that time, the initial value of the remaining propellant in the propellant tank at the final estimated satellite positioning time was M. a0 .

[0014] In the above-mentioned method for determining the initial value of remaining propellant in plate-type tanks for high-orbit satellites, when M exists... b0 The method for determining the initial value of the remaining propellant in the propellant tank at the final satellite positioning time is as follows: Compare M a0 and M b0 When |M a0 - M b0 │≤M C+b -M C+b-1 In this case, M is used directly. b0 This serves as the initial value for the remaining propellant in the propellant tank during the final assessment of the satellite's positioning. When |M a0 - M b0 │>M C+b -M C+b-1 When M is used, a0 This serves as the initial value for the remaining propellant in the propellant tank during the final assessment of the satellite's positioning.

[0015] The advantages of this invention compared to the prior art are: (1) The present invention provides another relatively independent method for determining the initial value of the remaining propellant in the tank when the satellite is stationary, in addition to the BK method, for high-orbit satellites with plate-type tanks. The error can be reduced to within 15 kg, which can significantly improve the evaluation accuracy of the initial value of the remaining propellant in the satellite at stationary position. (2) Compared with other methods such as the BK method of indirect calculation, the measurement of the present invention is more direct, has independent reliability, and can also be used to verify the results obtained by other methods; (3) This invention proposes a method for determining the initial value of the remaining propellant in a plate-type tank for high-orbit satellites. It is applicable to high-orbit satellite propulsion systems that use plate-type tanks. This method not only saves weight by using plate-type tanks, but also solves the problem of poor propellant condition assessment in the tank. Attached Figure Description

[0016] Figure 1 This is a schematic diagram showing the bonding position of the temperature measuring unit of the present invention; Figure 2 This is a schematic diagram showing the distribution of temperature measuring points in this invention; Figure 3 This is a schematic diagram of the temperature data curve of the present invention. Detailed Implementation

[0017] The present invention will be further described below with reference to the embodiments.

[0018] To address the issues of insufficient accuracy and limited methods in assessing the initial value of remaining propellant for high-orbit satellites using plate-type propellant tanks, this invention proposes a method for determining the initial value of remaining propellant in high-orbit satellites with plate-type propellant tanks. This method is independent of the traditional BK method and PVT method. On the one hand, it can be cross-validated with traditional methods; on the other hand, its assessment error can be reduced to within 15 kg compared to the traditional BK method, significantly improving the accuracy of assessing the initial value of remaining propellant for satellites at fixed points.

[0019] The method for determining the initial value of the remaining propellant in the plate-type propellant tank of a high-orbit satellite specifically includes the following steps: Based on the propellant budget of the satellite design, the remaining propellant in the tank at the end of the satellite's orbital maneuver is determined to be within the range [M2, M1]. Using the liquid volume calculation formula, the liquid level height [S2, S1] of the remaining propellant within the plate-type tank during the satellite's orbital control and bottoming-out state is calculated. The liquid level height is the distance from the propellant surface to the center spherical surface at the bottom of the tank.

[0020] Measuring units are attached to the outer surface of the plate-type storage tank, such as... Figure 1 As shown. The measuring unit includes a set of temperature measuring points and a heating belt.

[0021] The outer surface of the plate-type storage tank is uniformly distributed with guide strips along the circumference; the measuring unit is pasted between any two adjacent guide strips; the central temperature measuring point of the measuring unit is located at (S1+S2) / 2.

[0022] like Figure 2As shown, the number of temperature measuring points is set to 2N+1; the 2N+1 temperature measuring points are evenly spaced along the vertical direction, and their numbers from top to bottom are C+N, C+N+1, ..., C+1, C, C-1, ..., C-N+1, CN; the distance L1 between two adjacent temperature measuring points is 3-5mm; the coverage area L2 of the 2N+1 temperature measuring points is not less than S1-S2; the distance L3 between the heating belt and each temperature measuring point is 10-20mm.

[0023] Based on the geometric dimensions of the plate tank under working pressure and the density of the propellant at room temperature, determine the propellant mass M in the tank at each temperature measurement point location under the condition of propellant settling to the bottom. C+N M C+N …M C+1 M C M C-1 …M C-N+1 M C-N .

[0024] Three minutes before the satellite's final orbit change ignition, the heating belt was activated, and temperature data from each temperature measurement point was collected simultaneously.

[0025] Two minutes after the satellite's final orbital maneuver ignition, the heating element was shut off, and temperature data acquisition ceased. The temperature data curve is shown below. Figure 3 As shown.

[0026] Based on the temperature data from each temperature measurement point, calculate the temperature change rate ΔT at each temperature measurement point. C+N ..., ΔT C+1 ΔT C ΔT C-1 ..., ΔT C-N .

[0027] Two calculation methods were used to calculate the initial value M of the remaining propellant in the plate-type tank, based on the temperature change rate at each temperature measurement point. a0 and M b0 .

[0028] Calculate the initial value M of the remaining propellant in the plate tank. a0 The method is as follows: Compare the temperature change rate of adjacent temperature measurement points from 0 to 3 minutes.

[0029] When three consecutive temperature change rates at a certain adjacent temperature measurement point satisfy ΔT C+N >1.5×ΔT C+N-1 At this time, it is assumed that the propellant level in the tank is between temperature measuring points C+a and C+a-1 when the heating belt is activated 3 minutes before the end of the orbital change ignition; at this time, the remaining propellant in the tank is (M C+a +M C+a-1 ) / 2; then the initial value of the remaining propellant in the tank is M.a0 for: M a0 =(M C+a +M C+a-1 ) / 2-M 3min -M 捕获 In the formula, M 3min The BK method was used to calculate the propulsion dose consumed by the propellant tank during the last 3 minutes of satellite orbit control.

[0030] M 捕获 The BK method was used to calculate the propulsion dose consumed by the satellite for acquisition and positioning after the orbit change was completed.

[0031] When there are no adjacent temperature measurement points, there are three consecutive temperature change rates that satisfy ΔT C+N >1.5×ΔT C+N-1 At that time, the coefficient was reduced from 1.5 to 1.4, and the initial value M of the remaining propellant in the plate tank was calculated. a0 This continues until the initial value M of the remaining propellant in the plate tank is calculated. a0 .

[0032] Calculate the initial value M of the remaining propellant in the plate tank. b0 The method is as follows: Compare the temperature change rate at each temperature measurement point over 3-5 minutes.

[0033] When there are temperature measurement points that all satisfy ΔT within 3-5 minutes C+b >0, and the rate of temperature change ΔT at temperature measurement points above this point. C+b-1 …ΔT C+N If three or more consecutive data acquisition points satisfy <0, then it is considered that at the end of the satellite's orbit change ignition, the propellant level in the tank is between measurement points C+b and C+b-1, and the remaining propellant in the tank at this time is (M C+b +M C+b-1 ) / 2; then the initial value of the remaining propellant in the tank is M. b0 for: M b0 =(M C+b +M C+b-1 ) / 2-M 捕获 In the formula, M 捕获 The BK method was used to calculate the propulsion dose consumed by the satellite for acquisition and positioning after the orbit change was completed.

[0034] When there is no temperature measurement point, ΔT is satisfied for 3-5 minutes. C+b >0, and the rate of temperature change ΔT at temperature measurement points above this point. C+b-1 …ΔT C+NIf three or more consecutive data collection points satisfy the condition < 0, then the test condition is not met, and M does not exist. b0 .

[0035] Compare M a0 and M b0 The final estimated initial value of the remaining propellant in the propellant tank at the time of satellite positioning.

[0036] When M does not exist b0 At that time, the initial value of the remaining propellant in the propellant tank at the final estimated satellite positioning time was M. a0 .

[0037] When M exists b0 The method for determining the initial value of the remaining propellant in the propellant tank at the final satellite positioning time is as follows: Compare M a0 and M b0 When |M a0 - M b0 │≤M C+b -M C+b-1 In this case, M is used directly. b0 This serves as the initial value for the remaining propellant in the propellant tank during the final assessment of the satellite's positioning. When |M a0 - M b0 │>M C+b -M C+b-1 When M is used, a0 This serves as the initial value for the remaining propellant in the propellant tank during the final assessment of the satellite's positioning.

[0038] by Figure 3 Taking the example of the embodiment, 3 minutes before the ignition ends, temperature measurement points 1, 2, and 3 have a temperature rise rate that is 1.5 times greater than the temperature rise curves of other temperature measurement points. Therefore, at time t1, the liquid level in the tank is between temperature measurement points 3 and 4.

[0039] Two minutes after ignition, the temperature rise rate at temperature measurement point 5 is >0, while the temperature rise rates at temperature measurement points 1, 2, 3, and 4 all have periods of <0. Therefore, at time t2 after ignition, the liquid level in the tank is between temperature measurement points 4 and 5.

[0040] This invention provides a relatively independent method, besides the BK method, for determining the initial value of the remaining propellant in the tank during satellite positioning for high-orbit satellites with plate-type propellant tanks. The error can be reduced to within 15 kg, significantly improving the accuracy of the initial propellant remaining value assessment during satellite positioning. Compared to other methods such as the indirect calculation BK method, the measurement is more direct, has independent reliability, and can also be used to verify results obtained by other methods.

[0041] This invention proposes a method for determining the initial value of remaining propellant at a fixed point in plate-type tanks for high-orbit satellites. It is applicable to high-orbit satellite propulsion systems that use plate-type tanks, which not only saves weight by using plate-type tanks, but also solves the problem of poor propellant condition assessment in the tank.

[0042] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. A method for determining the initial value of remaining propellant in a plate-type propellant tank of a high-orbit satellite, characterized in that: include: Based on the propellant budget of the satellite design, the range of the remaining propellant in the tank at the end of the satellite's orbit change is [M2, M1]; Using the liquid volume calculation formula, the liquid level range [S2, S1] of the remaining propellant in the plate tank under the satellite orbit control bottoming state, with a remaining amount in the range of [M1, M2], is calculated. A measuring unit is attached to the outer surface of the plate-type storage tank; the measuring unit includes a set of temperature measuring points and a heating strip. Based on the geometric dimensions of the plate tank under working pressure and the density of the propellant at room temperature, determine the propellant mass M in the tank at each temperature measurement point location under the condition of propellant settling to the bottom. C+N M C+N …M C+1 M C M C-1 …M C-N+1 M C-N ; Turn on the heating belt and collect temperature data at each measuring point simultaneously; Turn off the heating element and stop collecting temperature data; Based on the temperature data from each temperature measurement point, calculate the temperature change rate ΔT at each temperature measurement point. C+N ..., ΔT C+1 ΔT C ΔT C-1 ..., ΔT C-N ; Two calculation methods were used to calculate the initial value M of the remaining propellant in the plate-type tank, based on the temperature change rate at each temperature measurement point. a0 and M b0 ; Compare M a0 and M b0 The final estimated initial value of the remaining propellant in the propellant tank at the time of satellite positioning.

2. The method for determining the initial value of remaining propellant in a plate-type propellant tank for high-orbit satellites according to claim 1, characterized in that: The liquid level height is the distance from the propellant liquid level to the center spherical surface at the bottom of the tank.

3. The method for determining the initial value of remaining propellant in a plate-type propellant tank for high-orbit satellites according to claim 1, characterized in that: The outer surface of the plate-type storage tank is uniformly distributed with guide strips along the circumference; the measuring unit is pasted between any two adjacent guide strips; the central temperature measuring point of the measuring unit is located at (S1+S2) / 2.

4. The method for determining the initial value of remaining propellant in a plate-type propellant tank for high-orbit satellites according to claim 3, characterized in that: The number of temperature measuring points is set to 2N+1; the 2N+1 temperature measuring points are evenly spaced vertically, and their numbers from top to bottom are C+N, C+N+1, ..., C+1, C, C-1, ..., C-N+1, CN; the distance L1 between two adjacent temperature measuring points is 3-5mm; the coverage area L2 of the 2N+1 temperature measuring points is not less than S1-S2; the distance L3 between the heating belt and each temperature measuring point is 10-20mm.

5. The method for determining the initial value of remaining propellant in a plate-type propellant tank for high-orbit satellites according to claim 1, characterized in that: The heating belt was activated 3 minutes before the satellite's final orbit change ignition ended.

6. The method for determining the initial value of remaining propellant in a plate-type propellant tank for high-orbit satellites according to claim 5, characterized in that: Two minutes after the satellite's final orbital maneuver ignition, the heating element was shut off.

7. The method for determining the initial value of remaining propellant in a plate-type propellant tank for high-orbit satellites according to claim 6, characterized in that: Calculate the initial value M of the remaining propellant in the plate tank. a0 The method is as follows: Compare the temperature change rate of adjacent temperature measurement points from 0 to 3 minutes. When three consecutive temperature change rates at a certain adjacent temperature measurement point satisfy ΔT C+N >1.5×ΔT C+N-1 At this time, it is assumed that the propellant level in the tank is between temperature measuring points C+a and C+a-1 when the heating belt is activated 3 minutes before the end of the orbital change ignition; at this time, the remaining propellant in the tank is (M C+a +M C+a-1 ) / 2; then the initial value of the remaining propellant in the tank is M. a0 for: M a0 =(M C+a +M C+a-1 ) / 2-M 3min -M 捕获 In the formula, M 3min The BK method was used to calculate the propellant charge consumed by the propellant tank during the last 3 minutes of satellite orbit control. M 捕获 The BK method was used to calculate the propellant charge consumed by the satellite during its acquisition and positioning after the orbit change was completed. When there are no adjacent temperature measurement points, there are three consecutive temperature change rates that satisfy ΔT C+N >1.5×ΔT C+N-1 At that time, the coefficient was reduced from 1.5 to 1.4, and the initial value M of the remaining propellant in the plate tank was calculated. a0 This continues until the initial value M of the remaining propellant in the plate tank is calculated. a0 .

8. The method for determining the initial value of remaining propellant in a plate-type propellant tank for high-orbit satellites according to claim 7, characterized in that: Calculate the initial value M of the remaining propellant in the plate tank. b0 The method is as follows: Compare the rate of temperature change at each temperature measurement point over 3-5 minutes; When there are temperature measurement points that all satisfy ΔT within 3-5 minutes C+b >0, and the rate of temperature change ΔT at temperature measurement points above this point. C+b-1 …ΔT C+N If three or more consecutive data acquisition points satisfy <0, then it is considered that at the end of the satellite's orbit change ignition, the propellant level in the tank is between measurement points C+b and C+b-1, and the remaining propellant in the tank at this time is (M C+b +M C+b-1 ) / 2; then the initial value of the remaining propellant in the tank is M. b0 for: M b0 =(M C+b +M C+b-1 ) / 2-M 捕获 In the formula, M 捕获 The BK method was used to calculate the propellant charge consumed by the satellite during its acquisition and positioning after the orbit change was completed. When there is no temperature measurement point, ΔT is satisfied for 3-5 minutes. C+b >0, and the rate of temperature change ΔT at temperature measurement points above this point. C+b-1 …ΔT C+N If three or more consecutive data collection points satisfy the condition < 0, then the test condition is not met, and M does not exist. b0 .

9. The method for determining the initial value of remaining propellant in a plate-type propellant tank for high-orbit satellites according to claim 8, characterized in that: When M does not exist b0 At that time, the initial value of the remaining propellant in the propellant tank at the final estimated satellite positioning time was M. a0 .

10. The method for determining the initial value of remaining propellant in a plate-type propellant tank for high-orbit satellites according to claim 8, characterized in that: When M exists b0 The method for determining the initial value of the remaining propellant in the propellant tank at the final satellite positioning time is as follows: Compare M a0 and M b0 When |M a0 - M b0 │≤M C+b -M C+b-1 In this case, M is used directly. b0 This serves as the initial value for the remaining propellant in the propellant tank during the final assessment of the satellite's positioning. When |M a0 - M b0 │>M C+b -M C+b-1 When M is used, a0 This serves as the initial value for the remaining propellant in the propellant tank during the final assessment of the satellite's positioning.

Images