CN112278330B - Electric propulsion position keeping method based on satellite-hour driving - Google Patents
Electric propulsion position keeping method based on satellite-hour driving Download PDFInfo
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- 238000000034 method Methods 0.000 title claims abstract description 28
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- 230000009191 jumping Effects 0.000 claims description 9
- 238000009434 installation Methods 0.000 claims description 3
- 238000007781 pre-processing Methods 0.000 claims description 3
- 238000005259 measurement Methods 0.000 description 4
- 238000010304 firing Methods 0.000 description 3
- 238000012423 maintenance Methods 0.000 description 2
- 239000003380 propellant Substances 0.000 description 2
- 238000011217 control strategy Methods 0.000 description 1
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Abstract
The invention relates to an electric propulsion position keeping method based on satellite-hour driving, which is characterized in that electric propulsion ignition task parameters are preprocessed and divided into strategy parameters and attribute parameters according to the fact whether the parameters change according to the task; through the star-hour driving, the initialization work, the steering adjustment of a vector adjusting mechanism, the parameter configuration of the electric thruster and the starting arc section processing before the ignition of each rail of the electric thruster are sequentially carried out according to the time sequence. The invention realizes the automatic ignition task of multi-orbit and multi-arc sections of electric propulsion, improves the autonomous operation capability of the satellite, and has better flexibility and expandability, and the ignition orbit number and the arc section number can be flexibly configured on the ground.
Description
Technical Field
The invention relates to an electric propulsion position keeping method based on satellite time drive, which is mainly used for software design and realization of satellite electric propulsion device position keeping and belongs to the field of spacecraft embedded software design.
Background
Electric propulsion is a spacecraft propulsion technology which utilizes electric energy to accelerate propulsion working media so as to realize high specific impulse. The low propellant consumption associated with high specific impulse can greatly reduce propellant carry over. The use of electric propulsion systems can extend satellite life, improve on-orbit performance, and increase load ratios compared to chemical propulsion. The electric propulsion is applied to the orbit lifting and the position keeping of the satellite and becomes a development trend. However, the thrust of electric propulsion is small, the position of an electric propulsion satellite is kept in a unit guarantee period of several weeks, the first days of each unit guarantee period are ensured by a ground orbit determination positioning guarantee strategy, and the rest time of the satellite is subjected to the unit guarantee ignition control for several times in each orbit and angular momentum unloading is carried out on the basis. The electric thruster is considered to be an arc segment of the satellite's orbit in each ignition period, and the electric propulsion position is maintained to be composed of a plurality of orbits and a plurality of arc segments.
Aiming at the characteristics of multiple tracks and multiple arc sections of an electric propulsion ignition task, the conventional thruster is completely started and shut down by depending on a ground measurement and control network, so that the workload is greatly increased. The invention provides an electric propulsion position keeping method based on satellite time drive, which uploads ignition parameters kept at all positions in a position keeping period once on the ground and automatically performs ignition by a satellite.
Disclosure of Invention
The technical problem solved by the invention is as follows: the method overcomes the defects of the prior art, provides an electric propulsion position maintaining method based on the satellite-hour driving, and solves the problem that the conventional thruster is completely dependent on a ground measurement and control network to start and stop.
The technical scheme of the invention is as follows: an electric propulsion position maintaining method based on a time-of-day drive comprises the following steps:
(1) preprocessing the parameters of the electric propulsion ignition task, and dividing the parameters into strategy parameters and attribute parameters according to whether the parameters change according to the characteristics of the task;
(2) and according to the strategy parameters and the attribute parameters, by means of star-hour driving, the initialization work, the steering adjustment of a vector adjusting mechanism, the parameter configuration of the electric thruster and the starting arc section processing before each rail of the electric thruster is ignited are sequentially carried out according to the time sequence.
The specific method of the step (1) comprises the following steps:
(11) each electrical thruster is indexed by a number 1,2 …, NUM, where NUM is the number of electrical thruster installations.
(12) Before each ignition task, the ignition task parameters are divided into strategy parameters and attribute parameters according to whether the ignition task parameters need to be updated on the ground.
The specific method of the step (12) is as follows:
(121) the policy parameters are characterized as a set of variables V: the number of ignition track cycles nrob, the number of starting arc segments nrc, the ignition length and position are indicated by the ignition start time TS and the ignition end time TE, and the thrust used for the starting arc segments is indicated by the number E. The strategy parameters for each firing contained (nOrb × nArc) TS, TE and E. The set of variable values is injected from the surface prior to each bit-preserving firing task.
(122) Attribute parameters are characterized as a set of variables R: the thrust time delay TD of each thruster, the time TP required by the angle of a preset vector adjusting mechanism and the configuration parameter time TC of each thruster. The attribute parameters all include NUM TDs. The set of parameters generally does not vary as the bit-keeping strategy varies.
The specific method of the step (2) is as follows:
(21) and taking out the time delay TD of the thruster corresponding to the arc section according to the thruster number E of the first starting arc section of each rail. And calculating the time Ti corresponding to the initialization before each rail is ignited according to the ignition starting time TS of the first arc section, the time delay TD of the thruster and the time TP required by the angle of the preset vector adjusting mechanism, namely Ti is TS-TD-TP. Judging the sizes of the satellite time Ta and Ti, if Ta is equal to Ti, then turning to the step (22) to carry out initialization work before each orbit ignition task, otherwise, turning to the step (31);
(22) setting the starting arc segment counter A to be 1, calculating the direction offset of thrusters used by all arc segments of the rail corresponding to the angular momentum unloading amount, and then turning to the step (23);
(23) carrying out steering adjustment processing on the vector adjusting mechanism of the first starting arc segment of each rail, and entering the step (24) when the vector adjusting mechanism is adjusted in place, or entering the step (31);
(24) adjusting the vector adjusting mechanism of the next starting arc section in advance, so that when the next starting arc section arrives, the used thruster points to the adjusted position, and then turning to the step (25); wherein the number of the next starting arc segment is A + 1;
(25) and calculating the parameter configuration time Tc which is TS-TD-TC. Judging the size of the satellite time Ta and the current startup arc section parameter configuration time Tc of the satellite, when Ta is equal to Tc, performing electric thruster parameter configuration by satellite software, and executing the step (26), otherwise, entering the step (31);
(26) judging the satellite time Ta of the satellite, if the satellite time Ta is equal to the starting time TS of the current starting arc section, turning to the step (27), otherwise, turning to the step (31);
(27) the on-board software sends an ignition instruction to the electric thruster of the current arc section; judging the satellite time Ta of the satellite, if the satellite time Ta is equal to the shutdown time TE of the current startup arc section, switching to (28), otherwise, switching to (31);
(28) the on-board software sends an ignition stopping instruction to the electric thruster of the current arc section, and then the step (29) is carried out;
(29) and judging the size of the current starting arc segment counter A and the starting arc segment number numSeq. If A is smaller than numSeq, setting the starting arc segment counter A to be A +1, and turning to the step (31) to execute the next starting arc segment ignition process; otherwise, entering the step (30);
(30) judging the sizes of the ignition orbit period counter O and the ignition orbit period number numOrb, if O is smaller than numOrb, setting the ignition orbit period counter O as O +1, then jumping to the step (31), and continuing the initialization work and the arc section processing of the next orbit; otherwise, jumping to step (32);
(31) repeating the steps (21) to (30) to carry out the ignition process of the next software control period;
(32) the ignition strategy parameter is set to 0. And ending the ignition task.
Compared with the prior art, the invention has the advantages that:
(1) aiming at the characteristic of electric propulsion position maintenance, the invention realizes the multi-track and multi-arc ignition task by preprocessing the ignition task parameters, the number of ignition tracks and the number of arc segments can be flexibly configured on the ground, the invention is suitable for the electric propulsion control strategies of different satellites, and has better flexibility and expandability.
(2) The invention can automatically execute the ignition process on the satellite by judging the satellite time through a satellite time driving mode until the whole ignition task is finished. The ground does not need to send the starting and shutdown instructions to the electric thrusters one by one, and the autonomous operation capability of the satellite is improved.
(3) The method is already applied to the electric propulsion position maintenance of a certain in-orbit satellite, and the feasibility and the effectiveness of the method are verified through engineering implementation.
Drawings
FIG. 1 is a table of ignition mission parameter composition structures;
FIG. 2 is a flow chart of an ignition arc segment process;
FIG. 3 is a flow chart of an electric propulsion position maintaining method based on a star hour drive according to the present invention;
Detailed Description
The invention relates to an electric propulsion position keeping method based on satellite-hour driving, aiming at the characteristics that the electric propulsion position keeps a plurality of tracks and a plurality of arc sections, the traditional electric propulsion position keeps completely relying on a ground measurement and control network to start and shut down a thruster. The invention realizes the automatic ignition task of multi-orbit and multi-arc sections of electric propulsion, improves the autonomous operation capability of the satellite, and has better flexibility and expandability, and the ignition orbit number and the arc section number can be flexibly configured on the ground. The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.
The invention relates to an electric propulsion position keeping method based on satellite-hour driving, which comprises the following specific steps as shown in figure 3:
firstly, identifying parameters of an electric spark ignition task:
each electrical thruster is numbered with a numerical index number 1,2 …, NUM, where NUM is the number of electrical thruster installations. According to the characteristics of ignition task parameter change, the parameters can be divided into strategy parameters and attribute parameters according to whether the parameters are changed according to the task. The composition of the policy parameters and the attribute parameters is shown in fig. 1.
The policy parameters are characterized as a set of variables V: number of ignition orbital periods numOrb, number of starting arc periods numArc, ignition duration and ignition start time TS for locationO,AAnd an ignition end time TEO,ATo show that the thrust used in the starting arc section is numbered ElecO,ATo indicate. The strategic parameters of each ignition include (numOrb × numarcc) elecsO,A、TSO,AAnd TEO,AThe subscript O indicates the ignition track cycle number and a indicates the starting arc segment number. The set of variable values is injected from the surface prior to each firing task.
Attribute parameters are characterized as a set of variables R: thrust time delay TD of each thrusterNPresetting time TP required by the angle of the vector adjusting mechanism and configuration parameter time TC of the thruster. Where the subscript N denotes the thruster number. The set of parameters generally does not vary as the bit-keeping strategy varies.
And secondly, initializing operation before ignition of each rail:
according to the number Elec of the thruster of the first starting arc section of each railO,1And taking out the time delay TDElec of the thruster corresponding to the arc sectionO,1。
Starting time of ignition TS according to first arc sectionO,1And thruster time delay TDElecO,1Presetting the time TP required by the angle of the vector adjusting mechanism, and calculating the time Ti corresponding to the initialization before each rail is ignited, wherein the time Ti is TSO,1-TDElecO,1-TP. Judging the satellite time Ta and Ti, when Ta is equal to Ti, setting the current starting arc segment number A to 1, and calculating the direction offset (dx) of the thruster for the rail corresponding to the angular momentum unloading amountN,dyN)。
Thirdly, steering adjustment processing of the vector adjusting mechanism:
according to the number Elec of the thruster of the first starting arc section of each railO,1Take out the arcThrust offset (dx) corresponding to segmentElecO,1,dyElecO,1) And converting the target rotation angle into a target rotation angle of the vector adjusting mechanism corresponding to the arc section, and sending the rotation angle to the vector adjusting mechanism. And in each software control period, judging whether the vector adjusting mechanism is adjusted in place or not according to the angle measurement value returned by the vector adjusting mechanism, if so, turning to the fourth step to execute starting arc section operation, otherwise, not starting ignition.
Fourthly, starting up arc section processing:
(1) thrust direction of thruster used for adjusting next starting arc section in advance
In the current starting arc section processing, the thrust direction of the next starting arc section is adjusted in advance, so that when the next starting arc section arrives, the used thruster points to the adjusted position. The thruster number of the next starting arc section is ElecO,A+1And the adjusting method is as the third step.
(2) Time-of-day drive thruster parameter configuration
Due to the power characteristic of the electric thruster, thrusts with different magnitudes can be generated, and the required electric thruster ignition configuration parameters are also different. Before the electric thruster is started, corresponding configuration parameters are selected in advance according to the thruster number used by the current arc section.
Calculating parameter configuration time Tc equal to TSO,A-TDElecO,A-TC. And (4) judging the size of the parameter configuration time Tc of the satellite time Ta and the current starting arc section, when Ta is equal to Tc, selecting corresponding working conditions by satellite software to carry out parameter binding, and then jumping to the step (3) to drive a starting instruction when executing the satellite.
(3) Star-time driving starting instruction
Judging the satellite time Ta and the ignition starting time TS of the current starting arc sectionO,AWhen Ta equals TSO,AIn time, the satellite software is given the number ElecO,AThe electric thruster gives an ignition command and drives a shutdown command when jumping to the step (4) to execute the planet.
(4) Time-of-day drive shutdown instruction
Judging the satellite time Ta and the ignition and shutdown time TE of the current startup arc sectionO,AWhen Ta equals TEO,AIn time, the satellite software is given the number ElecO,AThe electric thruster sends a command of stopping ignition and jumps to the fifth step. FIG. 2 is a flow chart of the boot arc segment process.
Fifthly, judging strategy for ending ignition task
(1) Starting arc segment ending judgment strategy
And judging the size of the current starting arc segment A number and the starting arc segment number numSeq. And if A is less than numSeq, setting the current starting arc segment number A to be A +1, and jumping to the fourth step to execute the next starting arc segment processing. And (3) if A is equal to numSeq, indicating that all the startup arcs of the track cycle O are executed, and jumping to the track cycle ending judgment strategy in the step (2).
(2) Track cycle end judgment strategy
Judging the sizes of the current ignition orbit period number O and the ignition orbit period number numOrb, if O is smaller than numOrb, setting the ignition orbit period number O to be O +1, and jumping to the second step to continue the initialization work and the arc segment processing of the next orbit. And if O is equal to numOrb, resetting the ignition strategy parameter V, and ending the ignition task.
Claims (2)
1. An electric propulsion position maintaining method based on time-of-day driving is characterized by comprising the following steps:
(1) preprocessing the parameters of the electric propulsion ignition task, and dividing the parameters into strategy parameters and attribute parameters according to whether the parameters change according to the characteristics of the task;
(2) according to the strategy parameters and the attribute parameters, initialization work, vector adjusting mechanism steering adjustment, electric thruster parameter configuration and starting arc section processing before ignition of each rail of the electric thruster are sequentially carried out according to the time sequence through star-hour driving;
the specific process of the step (1) is as follows:
(11) performing numerical number indexing 1,2 …, NUM on each electric thruster, wherein NUM is the number of electric thruster installations;
(12) before each ignition task, dividing the ignition task parameters into strategy parameters and attribute parameters according to whether the ignition task parameters need to be updated on the ground or not;
the specific method of the step (12) is as follows:
(121) the policy parameters are characterized as a set of variables V: the number of ignition track cycles numOrb, the number of startup arc segments numArc, the ignition duration and the position are represented by an ignition starting time TS and an ignition ending time TE, and the thrust used by the startup arc segments is represented by a number E; the strategy parameters of each ignition comprise (numOrb × numarcc) TS, TE and E; before each ignition task, the variable values are injected from the ground;
(122) attribute parameters are characterized as a set of variables R: thrust time delay TD of each thruster, time TP required by the angle of a preset vector adjusting mechanism, and configuration parameter time TC of each thruster; the attribute parameters comprise NUM TDs; the set of parameters does not change as the bit-keeping policy changes;
the specific method of the step (2) is as follows:
(21) taking out the thruster time delay TD corresponding to the arc section according to the serial number E of the thruster used by the starting arc section; calculating the initial corresponding time Ti before each rail is ignited according to the ignition starting time TS of the first starting arc section, the time delay TD of the thruster and the time TP required by the angle of the preset vector adjusting mechanism; judging the sizes of the satellite time Ta and Ti, if Ta is equal to Ti, then turning to the step (22) to carry out initialization work before each orbit ignition task, otherwise, turning to the step (31);
(22) setting the starting arc segment counter A to be 1, calculating the direction offset of thrusters used by all arc segments of the rail corresponding to the angular momentum unloading amount, and then turning to the step (23);
(23) carrying out steering adjustment processing on the vector adjusting mechanism of the first starting arc segment of each rail, and entering the step (24) when the vector adjusting mechanism is adjusted in place, or entering the step (31);
(24) adjusting the vector adjusting mechanism of the next starting arc section in advance, so that when the next starting arc section arrives, the used thruster points to the adjusted position, and then turning to the step (25); wherein the number of the next starting arc segment is A + 1;
(25) calculating the parameter configuration time Tc which is TS-TD-TC; judging the size of the satellite time Ta and the current startup arc section parameter configuration time Tc of the satellite, when Ta is equal to Tc, performing electric thruster parameter configuration by satellite software, and executing the step (26), otherwise, entering the step (31);
(26) judging the satellite time Ta of the satellite, if the satellite time Ta is equal to the starting time TS of the current starting arc section, turning to the step (27), otherwise, turning to the step (31);
(27) the on-board software sends an ignition instruction to the electric thruster of the current arc section; judging the satellite time Ta of the satellite, if the satellite time Ta is equal to the shutdown time TE of the current startup arc section, switching to (28), otherwise, switching to (31);
(28) the on-board software sends an ignition stopping instruction to the electric thruster of the current arc section, and then the step (29) is carried out;
(29) judging the sizes of a current starting arc segment counter A and a starting arc segment number numarcc; if A is smaller than numarcc, setting the starting arc segment counter A as A +1, and then turning to the step (31) to execute the next starting arc segment ignition process; otherwise, entering the step (30);
(30) judging the sizes of the ignition orbit period counter O and the ignition orbit period numOrb, if O is smaller than numOrb, setting the ignition orbit period counter O to be O +1, and then jumping to the step (31); otherwise, jumping to step (32);
(31) repeating steps (21) - (30);
(32) setting ignition strategy parameters to be 0; and ending the ignition task.
2. An electric propulsion position maintaining method based on a star time drive as claimed in claim 1, characterized in that: in step (21), the corresponding time Ti before ignition per rail is initialized to TS-TD-TP.
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| US6135394A (en) * | 1998-12-08 | 2000-10-24 | Space Systems/Loral, Inc. | Practical method and apparatus for satellite stationkeeping |
| FR3022530B1 (en) * | 2014-06-19 | 2018-03-02 | Airbus Defence And Space Sas | METHOD FOR CONTROLLING THE ORBIT OF A SATELLITE IN TERRESTRIAL ORBIT, SATELLITE AND SYSTEM FOR CONTROLLING THE ORBIT OF SUCH A SATELLITE |
| CN105373133B (en) * | 2015-11-26 | 2018-05-01 | 中国空间技术研究院 | A kind of geo-stationary orbit electric propulsion position is kept and angular momentum dumping combination control method |
| CN105353621B (en) * | 2015-11-30 | 2018-05-22 | 北京控制工程研究所 | A kind of geostationary orbit satellite electric thruster fault mode thrust distribution method |
| CN106697332B (en) * | 2016-11-23 | 2018-10-19 | 中国空间技术研究院 | A kind of full electric propulsion satellite platform position holding electric thruster redundancy configuration method |
| CN108490963B (en) * | 2018-02-08 | 2021-03-26 | 中国空间技术研究院 | Position keeping method and system under fault mode of full-electric propulsion satellite electric thruster |
| CN109063380B (en) * | 2018-09-12 | 2023-02-17 | 北京理工大学 | Fault detection method and position maintenance method for stationary orbit electric propulsion satellite |
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