CN106081167A - The magnetic control of a kind of province working medium and gas puff Z-pinch united high-precision attitude control method - Google Patents

Abstract

The present invention relates to the magnetic control of a kind of province working medium and gas puff Z-pinch united high-precision attitude control method, step be (1) according to three-axis attitude error and angular velocity error, utilize PID control law to calculate and expect control moment；(2) in the real-time distribution of satellite body coordinate system triaxial coordinate component, base area magnetic flux density vector determines which axle attitude implements magnetic control, which axle attitude implements gas puff Z-pinch；(3) utilize microvariations magnetic moment allocation algorithm to calculate three axle magnetic moments, fully to meet magnetic control axle desired control moment, reduce disturbance torque produced by magnetic control simultaneously；(4) jet phase plane algorithm is utilized to calculate the jet pulsewidth of gas puff Z-pinch axle.The attitude control accuracy of the present invention is high, and working medium consumes low, calculates simple, and Project Realization is easy.

Description

The magnetic control of a kind of province working medium and gas puff Z-pinch united high-precision attitude control method

Technical field

The present invention relates to magnetic control and the gas puff Z-pinch united high-precision attitude control method of a kind of province working medium, it is adaptable to institute Have and use magnetic control to combine the spacecraft realizing high accuracy three-axis attitude stabilization, such as gravity field measurement satellites and height with gas puff Z-pinch The scientific exploration satellite etc. of quiet degree.The method apply also for other all have that momenttum wheel or CMG coordinate need magnetic control Spacecraft or spacecraft specific operation mode.

Background technology

For Gravisat, the task of accelerometer is to measure the nonconservative force impact on celestial body center of mass motion. Being characterized in, sensitivity is the highest, and high and low frequency vibration suffered in task, the amplitude of disturbance, frequency etc. are had strict wanting Ask.Based on this requirement, satellite controls subsystem to be needed to reduce the disturbance to celestial body barycenter acceleration as far as possible, it is to be ensured that by appearance State measures the celestial body barycenter acceleration caused with control does not affect the work of accelerometer or gravity gradiometer.Therefore, control to divide System needs from reducing vibration and the angle of disturbance is designed: i.e., do not use such as band rotating mechanism sensor and Actuator etc. can have a strong impact on platform payload work parts, as common momenttum wheel, solar array drive mechanism and Scan-type earth sensors etc., only use magnetic torquer and jet actuator to realize the highest attitude control accuracy index and want Asking, propulsive working medium can not be liquid, and the time that jet actuator participates in controlling is the fewest.

In order to meet the normal requirements of one's work of payload high-precision accelerometer, gravity field measurement satellites can not be joined Being equipped with sensor and the actuator of movable member, therefore the commonly used magnetic control of its attitude control system is united with gas puff Z-pinch Scheme, ensures attitude control accuracy by gas puff Z-pinch, saves propulsive working medium by magnetic control.In the world CHAMP, GRACE and Three generations's gravity field measurement satellites such as GOCE all use this control program, but concrete control algolithm has no the open report of document. To this end, carrying out China's gravity field measurement satellites tackling problems in key technologies and ground demonstration Qualify Phase, seminar holds magnetic control This key link, successively attempted PID magnetic control method based on tradition magnetic moment distribution, based on magnetic control method theoretical for H ∞ and Based on various control algorithms such as the magnetic control method that convex polyhedron is theoretical, but result is the most not ideal enough, and propulsive working medium consumption is long-range Level in direct read out GRACE.Later, this patent declarer found document " the skin attitude of satellite based on pure magnetic control Recover, journal of Zhejiang university (engineering version), 2013,47 (5): 843-852 ", use for reference its satellite yaw-position and do not control, control based on PD System rule realizes rolling the thought controlled with pitch attitude degree of precision by magnetic moment distribution, according to ground magnetic strength in the orbital period Answer intensity situation of change in satellite orbit coordinate system, propose to distribute dynamically, dexterously gas puff Z-pinch and magnetic between three axles The thought of control fully excavation magnetic moment distribution potentiality, forms magnetic control and the gas puff Z-pinch united high accuracy appearance of a kind of province working medium State control method, on the premise of three-axis attitude control accuracy fully meets index request, makes propulsive working medium consumption be better than GRACE The level of satellite.

Summary of the invention

The technology of the present invention solves problem: in place of overcoming the deficiencies in the prior art, it is provided that the magnetic control of a kind of province working medium with Gas puff Z-pinch united high-precision attitude control method, the method is obtained in that high attitude control accuracy, simultaneously working medium consumption Low, calculate simple, Project Realization is easy.

The technical solution of the present invention is: the magnetic control of a kind of province working medium controls with the united high-precision attitude of gas puff Z-pinch Method, its feature is that step is as follows:

(1) according to three-axis attitude error and angular velocity error, PID control law is utilized to be calculated three axle desired control power Square, the foundation calculated as magnetic control below；

(2) magnetic control axle/gas puff Z-pinch axle distribution logic: base area magnetic flux density vector is at satellite body coordinate system three axle The real-time distribution of coordinate components determines which axle attitude implements magnetic control calculating, which axle attitude is implemented gas puff Z-pinch and calculated, respectively Referred to as magnetic control axle, gas puff Z-pinch axle；

(3) for the magnetic control axle determined in step (2), according to the corresponding direction of principal axis desired control power be given in step (1) Square, and earth induction strength vector information, utilize microvariations magnetic moment allocation algorithm to be calculated three axle magnetic moment results, with the fullest Foot magnetic control axle desired control moment, reduces disturbance torque produced by magnetic control simultaneously, and this three axles magnetic moment result of calculation is as output；

(4) for the gas puff Z-pinch axle determined in step (2), jet phase plane algorithm is utilized to be calculated gas puff Z-pinch axle Jet pulsewidth result, this jet pulsewidth result of calculation is as output.

Described step (1) utilizes PID control law calculate three axle desired control moments as follows:

If along body coordinate system three axle, it is followed successively by rolling, pitching, the attitude error of yaw axis are [φ_c θ_c ψ_c], angle speed Degree error isThe PID coefficient of three axles is respectively Proportional coefficient K_px,K_py,K_pz, differential coefficient K_dx,K_dy,K_dz, Integral coefficient K_ix,K_iy,K_iz, then the desired control moment of three axles is calculated as below:

$T_{cx}=K_{px}{\mathrm{\φ}}_c+K_{dx}{\stackrel{\·}{\mathrm{\φ}}}_c+K_{ix}{\∫}_0^t{\mathrm{\φ}}_{c}dt$

$T_{cy}=K_{py}{\mathrm{\θ}}_c+K_{dy}{\stackrel{\·}{\mathrm{\θ}}}_c+K_{iy}{\∫}_0^t{\mathrm{\θ}}_{c}dt.$

$T_{cz}=K_{pz}{\mathrm{\ψ}}_c+K_{dz}{\stackrel{\·}{\mathrm{\ψ}}}_c+K_{iz}{\∫}_0^t{\mathrm{\ψ}}_{c}dt$

The magnetic control axle of described step (2)/gas puff Z-pinch axle distribution logic, is according to the track Distribution of Magnetic Field feelings residing for satellite Condition, determines which axle is magnetic control axle when track diverse location, and which axle is gas puff Z-pinch axle.Concrete distribution logic is as follows:

If along body coordinate system three axle, it is followed successively by rolling, pitching, the earth induction intensity of yaw axis are [B_x B_y B_z], when Before if | B_x|>|B_z|, then Y-axis i.e. pitch axis is set, Z axis i.e. yaw axis is magnetic control axle, and the X-axis i.e. axis of rolling is gas puff Z-pinch axle；No Then arranging X-axis and Y-axis is magnetic control axle, Z axis is gas puff Z-pinch axle.

Microvariations magnetic moment allocation algorithm in described step (3), is to utilize three axle magnetic moments, to reduce the disturbance that magnetic moment brings Moment is top-priority allocation algorithm, and concrete allocation algorithm is as follows:

(31) if being magnetic control axle according to current Y-axis i.e. pitch axis and Z axis i.e. yaw axis, then:

First two alternative magnetic moment values M are calculated_x1=-T_cy/B_z, M_x2=T_cz/B_y, wherein T_cy、T_czIt is respectively pitch axis, partially Boat axle desired control moment values, B_y、B_zBe respectively earth induction intensity at body coordinate system pitch axis, the component value of yaw axis, if M_x1With M_x2Jack per line, then axis of rolling magnetic moment M_xComputing formula is: M_x=sgn (M_x1)min(M_x1,M_x2)；Otherwise make M_x=0；

Then yaw axis magnetic moment M is calculated_z=(T_cy+M_xB_z)/B_x, pitch axis magnetic moment M_y=(M_xB_y-T_cz)/B_x, wherein B_xFor Earth induction intensity is at the component value of the body coordinate system axis of rolling.

(32) if being magnetic control axle according to current X-axis, the i.e. axis of rolling and Y-axis, i.e. pitch axis, then:

First two alternative magnetic moment values M are calculated_z1=-T_cx/B_y, M_z2=T_cy/B_x, wherein T_cx、T_cyIt is respectively the axis of rolling, bows Face upward axle desired control moment values, B_x、B_yBe respectively earth induction intensity at the body coordinate system axis of rolling, the component value of pitch axis, if M_z1With M_z2Jack per line, then yaw axis magnetic moment M_zComputing formula is M_z=sgn (M_z1)min(M_z1,M_z2)；Otherwise make M_z=0；

Then pitch axis magnetic moment M is calculated_y=(T_cx+M_zB_y)/B_z, axis of rolling magnetic moment M_x=(M_zB_x-T_cy)/B_z, wherein B_zFor Earth induction intensity is at the component value of body coordinate system yaw axis；

(33) magnetic moment amplitude limit

If the maximum magnetic moment M of magnetic torquer_max, to above result of calculation M_x,M_y,M_zCarry out amplitude limiting processing M_x=mlf (M_x, M_max), M_y=mlf (M_y,M_max), M_z=mlf (M_z,M_max)。

Present invention advantage compared with prior art is:

(1) magnetic control jointly controls with jet, has both made full use of magnetic control ability and has saved jet working medium, turn avoid magnetic control attitude The shortcoming that control accuracy is the highest.

(2) base area magnetic flux density vector determines magnetic control axle/gas puff Z-pinch in the component feature of satellite body coordinate system Axle distributes, and makes magnetic control moment loading in the highest direction of efficiency, it is possible to give full play to magnetic control ability, avoid magnetic control moment pair simultaneously Other axles produce larger interference.

(3) microvariations magnetic moment allocation algorithm considers expectation moment and the distribution of earth induction strength vector, fully excavates Three axle magnetic moment potentiality, on the premise of fully meeting magnetic control axle expectation torque requirement, reduce the magnetic control interference to other axles as far as possible Moment.

In a word, the present invention has passed through verification experimental verification in certain Gravisat demonstration and verification project, and method is feasible, engineering Technology easily realizes, and therefore has practicality.

Accompanying drawing explanation

Fig. 1 is that magnetic control of the present invention combines high-precision attitude control flow chart with gas puff Z-pinch.

Detailed description of the invention

Embodiment 1:

As a example by a kind of orbit inclination angle low orbit satellite near 90 degree, as it is shown in figure 1, the concrete steps of the present invention are such as Under:

(1) according to three-axis attitude error and angular velocity error, PID control law is utilized to calculate expectation control moment；If along this The attitude error of body coordinate system three axle (being followed successively by rolling, pitching, yaw axis, the most same) is [φ_c θ _cψ_c], angular velocity is by mistake Difference isThe PID coefficient of three axles is respectively Proportional coefficient K_px,K_py,K_pz, differential coefficient K_dx,K_dy,K_dz, integration COEFFICIENT K_ix,K_iy,K_iz, then the desired control moment of three axles is calculated as below:

$T_{cx}=K_{px}{\mathrm{\φ}}_c+K_{dx}{\stackrel{\·}{\mathrm{\φ}}}_c+K_{ix}{\∫}_0^t{\mathrm{\φ}}_{c}dt$

$T_{cy}=K_{py}{\mathrm{\θ}}_c+K_{dy}{\stackrel{\·}{\mathrm{\θ}}}_c+K_{iy}{\∫}_0^t{\mathrm{\θ}}_{c}dt.$

$T_{cz}=K_{pz}{\mathrm{\ψ}}_c+K_{dz}{\stackrel{\·}{\mathrm{\ψ}}}_c+K_{iz}{\∫}_0^t{\mathrm{\ψ}}_{c}dt$

(2) which axle appearance base area magnetic flux density vector determines in the size of satellite body coordinate system triaxial coordinate component State implements magnetic control, which axle attitude implements gas puff Z-pinch；Magnetic control axle/gas puff Z-pinch axle distribution logic is as follows:

If the earth induction intensity along body coordinate system three axle (being followed successively by rolling, pitching, yaw axis) is [B_x B_y B_z], If current | B_x|>|B_z|, then Y-axis (i.e. pitch axis) being set and Z axis (i.e. yaw axis) is magnetic control axle, X-axis (i.e. the axis of rolling) is jet Control axle；Otherwise arranging X-axis and Y-axis is magnetic control axle, Z axis is gas puff Z-pinch axle.

(3) microvariations magnetic moment allocation algorithm is utilized to calculate three axle magnetic moments, fully to meet magnetic control axle desired control moment, with Time reduce disturbance torque produced by magnetic control；Microvariations magnetic moment allocation algorithm is as follows:

If a. Y-axis and Z axis are magnetic control axle, then:

First two alternative magnetic moment values M are calculated_x1=-T_cy/B_z, M_x2=T_cz/B_y, wherein T_cy、T_czIt is respectively in step (1) The pitch axis of calculating, yaw axis desired control moment values, B_y、B_zIt is respectively earth induction intensity at body coordinate system pitch axis, partially The component value of boat axle, if M_x1With M_x2Jack per line, then axis of rolling magnetic moment M_xComputing formula is: M_x=sgn (M_x1)min(M_x1,M_x2)；No Then make M_x=0；

Then yaw axis magnetic moment M is calculated_z=(T_cy+M_xB_z)/B_x, pitch axis magnetic moment M_y=(M_xB_y-T_cz)/B_x, wherein B_xFor Earth induction intensity is at the component value of the body coordinate system axis of rolling.

If b. X-axis and Y-axis are magnetic control axle, then:

First two alternative magnetic moment values M are calculated_z1=-T_cx/B_y, M_z2=T_cy/B_x, wherein T_cx、T_cyIt is respectively in step (1) The axis of rolling of calculating, pitch axis desired control moment values, B_x、B_yBe respectively earth induction intensity at the body coordinate system axis of rolling, bow Face upward the component value of axle, if M_z1With M_z2Jack per line, then yaw axis magnetic moment M_zComputing formula is M_z=sgn (M_z1)min(M_z1,M_z2)；Otherwise Make M_z=0；

Then pitch axis magnetic moment M is calculated_y=(T_cx+M_zB_y)/B_z, axis of rolling magnetic moment M_x=(M_zB_x-T_cy)/B_z, wherein B_zFor Earth induction intensity is at the component value of body coordinate system yaw axis.

C. magnetic moment amplitude limit:

If the maximum magnetic moment M of magnetic torquer_max, to above result of calculation M_x,M_y,M_zCarry out amplitude limiting processing M_x=mlf (M_x, M_max), M_y=mlf (M_y,M_max), M_z=mlf (M_z,M_max)。

(4) utilizing jet phase plane algorithm to calculate the jet pulsewidth of gas puff Z-pinch axle, algorithm design reference slaughters kind clear academician " Satellite Attitude Dynamics and control " (Yuhang Publishing House, 2001) of chief editor page 442；

(5) in the whole work process of satellite, repeat the magnetic control shown in Fig. 1 and combine gesture stability stream with gas puff Z-pinch Journey, thus realize province's working medium and high-precision gesture stability, it is ensured that safety satellite effectively completes scientific exploration task.

Claims (4)

1. the magnetic control saving working medium and gas puff Z-pinch united high-precision attitude control method, it is characterised in that include following step Rapid:

(1) according to three-axis attitude error and angular velocity error, utilize PID control law to be calculated three axle desired control moments, make The foundation calculated for magnetic control below；

(2) magnetic control axle/gas puff Z-pinch axle distribution logic: base area magnetic flux density vector is at satellite body coordinate system triaxial coordinate The real-time distribution of component determines which axle attitude implements magnetic control calculating, which axle attitude is implemented gas puff Z-pinch and calculated, and is referred to as respectively For magnetic control axle, gas puff Z-pinch axle；

(3) for the magnetic control axle determined in step (2), according to the corresponding direction of principal axis desired control moment be given in step (1), and Earth induction strength vector information, utilizes microvariations magnetic moment allocation algorithm to be calculated three axle magnetic moment results, fully to meet magnetic Control axle desired control moment, reduces disturbance torque produced by magnetic control simultaneously, and this three axles magnetic moment result of calculation is as output；

(4) for the gas puff Z-pinch axle determined in step (2), jet phase plane algorithm is utilized to be calculated the spray of gas puff Z-pinch axle Gaseous pulse width result, this jet pulsewidth result of calculation is as output.

The magnetic control of province the most according to claim 1 working medium and gas puff Z-pinch united high-precision attitude control method, it is special Levy and be: described step (1) utilizes PID control law calculate three axle desired control moments as follows:

If along body coordinate system three axle, it is followed successively by rolling, pitching, the attitude error of yaw axis are [φ_c θ_c ψ_c], angular velocity is by mistake Difference isThe PID coefficient of three axles is respectively Proportional coefficient K_px,K_py,K_pz, differential coefficient K_dx,K_dy,K_dz, integration COEFFICIENT K_ix,K_iy,K_iz, then the desired control moment of three axles is calculated as below:

$T_{cx}=K_{px}{\mathrm{\φ}}_c+K_{dx}{\stackrel{\·}{\mathrm{\φ}}}_c+K_{ix}{\∫}_0^t{\mathrm{\φ}}_{c}dt$

$T_{cy}=K_{py}{\mathrm{\θ}}_c+K_{dy}{\stackrel{\·}{\mathrm{\θ}}}_c+K_{iy}{\∫}_0^t{\mathrm{\θ}}_{c}dt.$

$T_{cz}=K_{pz}{\mathrm{\ψ}}_c+K_{dz}{\stackrel{\·}{\mathrm{\ψ}}}_c+K_{iz}{\∫}_0^t{\mathrm{\ψ}}_{c}dt$

The magnetic control of province the most according to claim 1 working medium and gas puff Z-pinch united high-precision attitude control method, it is special Levy and be: the magnetic control axle of described step (2)/gas puff Z-pinch axle distribution logic, is according to the track Distribution of Magnetic Field feelings residing for satellite Condition, determines which axle is magnetic control axle when track diverse location, and which axle is gas puff Z-pinch axle, and concrete distribution logic is as follows:

If along body coordinate system three axle, it is followed successively by rolling, pitching, the earth induction intensity of yaw axis are [B_x B_y B_z], if current |B_x|>|B_z|, then Y-axis i.e. pitch axis is set, Z axis i.e. yaw axis is magnetic control axle, and the X-axis i.e. axis of rolling is gas puff Z-pinch axle；Otherwise set Putting X-axis and Y-axis is magnetic control axle, Z axis is gas puff Z-pinch axle.

The magnetic control of province the most according to claim 1 working medium and gas puff Z-pinch united high-precision attitude control method, it is special Levy and be: the microvariations magnetic moment allocation algorithm in described step (3), be to utilize three axle magnetic moments, to reduce the disturbance that magnetic moment brings Moment is top-priority allocation algorithm, and concrete allocation algorithm is as follows:

(31) if being magnetic control axle according to current Y-axis i.e. pitch axis and Z axis i.e. yaw axis, then:

First two alternative magnetic moment values M are calculated_x1=-T_cy/B_z, M_x2=T_cz/B_y, wherein T_cy、T_czIt is respectively pitch axis, yaw axis Desired control moment values, B_y、B_zRespectively earth induction intensity is at body coordinate system pitch axis, the component value of yaw axis, if M_x1 With M_x2Jack per line, then axis of rolling magnetic moment M_xComputing formula is: M_x=sgn (M_x1)min(M_x1,M_x2)；Otherwise make M_x=0；

Then yaw axis magnetic moment M is calculated_z=(T_cy+M_xB_z)/B_x, pitch axis magnetic moment M_y=(M_xB_y-T_cz)/B_x, wherein B_xFor ground magnetic strength Answer intensity at the component value of the body coordinate system axis of rolling；

(32) if being magnetic control axle according to current X-axis, the i.e. axis of rolling and Y-axis, i.e. pitch axis, then:

First two alternative magnetic moment values M are calculated_z1=-T_cx/B_y, M_z2=T_cy/B_x, wherein T_cx、T_cyIt is respectively the axis of rolling, pitch axis Desired control moment values, B_x、B_yRespectively earth induction intensity is at the body coordinate system axis of rolling, the component value of pitch axis, if M_z1 With M_z2Jack per line, then yaw axis magnetic moment M_zComputing formula is M_z=sgn (M_z1)min(M_z1,M_z2)；Otherwise make M_z=0；

Then pitch axis magnetic moment M is calculated_y=(T_cx+M_zB_y)/B_z, axis of rolling magnetic moment M_x=(M_zB_x-T_cy)/B_z, wherein B_zFor ground magnetic strength Answer intensity at the component value of body coordinate system yaw axis；

(33) magnetic moment amplitude limit

If the maximum magnetic moment M of magnetic torquer_max, to above result of calculation M_x,M_y,M_zCarry out amplitude limiting processing M_x=mlf (M_x,M_max), M_y=mlf (M_y,M_max), M_z=mlf (M_z,M_max)。