CN103241390B - Micro-nano satellite flight attitude control setup and method - Google Patents

Abstract

The present invention proposes a kind of micro-nano satellite flight attitude control setup and method, comprise: fuzzy adapted PI control device, actuator, high power density motor and flywheel body, wherein: fuzzy adapted PI control device is for sending adjustable duty cycle impulse singla to actuator; Actuator is connected with fuzzy adapted PI control device, for adjustable duty cycle impulse singla is converted to moment of momentum control signal, and is sent to high power density motor; High power density motor is connected with actuator, for controlling flywheel body according to moment of momentum control signal; Flywheel body is connected with high power density motor, controls micro-nano satellite flight attitude for exporting variable angular momentum under the driving of high power density motor.Micro-nano satellite flight attitude control setup of the present invention has possessed that self adaptation absorbs the various distrubing moments of period in-orbit, hyper-speed response, pinpoint accuracy, zero tracking error and self adaptation resist the advantages such as external disturbance.

Description

Micro-nano satellite flight attitude control device and method

Technical Field

The invention belongs to the technical field of satellite attitude control, and particularly relates to a micro-nano satellite flight attitude control device and method.

Background

With the development of high and new technologies such as micron/nanometer and the like, the technical research of nano satellites below 10 kg becomes one of the hotspots of the international satellite technical research, and the technical research of micro nano satellites is vigorously developed by various countries, so that the micro nano satellites can be more specifically applied to the aspects of military affairs, communication, geological exploration, environment and disaster monitoring, meteorological services, scientific experiments, deep space exploration and the like. The reaction wheel/momentum wheel of the nano satellite attitude control actuator is arranged in the directions of three main inertia axes of a satellite body coordinate system, the interference of environmental torque on the satellite body is absorbed by adjusting the rotating speed of a flywheel and adopting a momentum exchange mode, the three axes of the satellite are kept stable, and the satellite can do attitude maneuver around three axes of pitching, rolling and yawing to meet the requirements of satellite payload work and flight tests. The nano satellite has small volume, small inertia and light weight, and is influenced by a plurality of unknown disturbance moments during flying, so that the attitude of the satellite deviates from a preset ideal state due to long-time accumulation, and the normal operation is influenced. The micro momentum wheel theoretical model is required to approach an actual system model, the friction torque is subjected to nonlinear change along with the change of the temperature and the rotating speed of the flywheel, and the factors with large inertia ratio are designed to provide requirements for the dynamic performance and the accurate control of the attitude adjustment of the nano satellite.

Disclosure of Invention

The present invention aims to solve at least one of the above technical problems to at least some extent or to at least provide a useful commercial choice. Therefore, the first purpose of the invention is to provide a device for controlling the flight attitude of the micro-nano satellite, and the second purpose of the invention is to provide a method for controlling the flight attitude of the micro-nano satellite.

The micro/nano satellite flight attitude control device comprises: fuzzy self-adaptation PI controller, driver, high power density motor and flywheel body, wherein: the fuzzy self-adaptive PI controller is used for sending an adjustable duty ratio pulse signal to the driver; the driver is connected with the fuzzy self-adaptive PI controller and used for converting the adjustable duty ratio pulse signal into an angular momentum control signal and sending the angular momentum control signal to the high-power-density motor; the high-power density motor is connected with the driver and used for controlling the flywheel body according to the angular momentum control signal; the flywheel body is connected with the high-power-density motor and used for outputting variable angular momentum under the driving of the high-power-density motor to control the flight attitude of the micro-nano satellite.

Preferably, the driver is further configured to collect a torque voltage signal and a protection voltage signal of the high power density motor, and send the signals to the fuzzy adaptive PI controller.

Preferably, the fuzzy adaptive PI controller includes: speed measuring module, comparator, self-adaptation rotational speed controller, treater, self-adaptation motor controller, comparison filter and current controller, wherein: the speed measuring module is connected with the high-power-density motor and used for acquiring a rotating speed signal of the high-power-density motor and sending the rotating speed signal to the comparator; the comparator is connected with the speed measuring module and used for comparing the rotating speed signal with a given control quantity to obtain a rotating speed error and sending the rotating speed error to the self-adaptive rotating speed controller; the self-adaptive rotating speed controller is connected with the comparator and used for converting the rotating speed error into a rotating speed control quantity and sending the rotating speed control quantity to the processor; the self-adaptive motor controller is respectively connected with the high-power-density motor and the driver and is used for collecting motor torque characteristic current of the high-power-density motor, converting the motor torque characteristic current into torque current control quantity and sending the torque current control quantity to the processor; the processor is connected with the self-adaptive rotating speed controller and the self-adaptive motor controller and is used for converting the rotating speed control quantity and the torque current control quantity into voltage signal control quantity and sending the voltage signal control quantity to the comparison filter; the comparison filter is connected with the driver and the processor and used for comparing the torque voltage signal, the protection voltage signal and the voltage signal control quantity to obtain a comparison voltage signal and sending the comparison voltage signal to the current controller; the current controller is connected with the self-adaptive motor controller and the comparison filter, and is used for converting the comparison voltage signal into a comparison current signal and sending the comparison current signal to the self-adaptive motor controller; and the self-adaptive motor controller converts the comparison current signal into the pulse signal with the adjustable duty ratio and sends the pulse signal to the driver.

The micro-nano satellite flight attitude control device has the advantages of self-adaptive absorption of various disturbance torques in an in-orbit period, ultrahigh-speed response, high accuracy, zero tracking error, self-adaptive resistance to external disturbance and the like.

The method for controlling the flight attitude of the micro/nano satellite comprises the following steps: a: establishing a mathematical model of the micro-nano satellite flight attitude control device; b: and designing the control quantity of a fuzzy self-adaptive PI controller of the micro-nano satellite flight attitude control device.

Preferably, step a further comprises: the micro-nano satellite flight attitude control device consists of a fuzzy self-adaptive PI controller, a driver, a high-power density motor and a flywheel body,

a1: the voltage of each phase of the high-power-density motor is equal to the sum of the resistance voltage drop of the winding and the induced potential of the winding, and after reasonable assumption is made, the three-phase voltage of the winding A, B, C can be expressed as:

<math> <mrow> <msub> <mi>U</mi> <mi>A</mi> </msub> <mo>=</mo> <msub> <mi>Ri</mi> <mi>A</mi> </msub> <mo>+</mo> <mfrac> <mi>d</mi> <mi>dt</mi> </mfrac> <mrow> <mo>(</mo> <msub> <mi>L</mi> <mi>A</mi> </msub> <msub> <mi>i</mi> <mi>A</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>AB</mi> </msub> <msub> <mi>i</mi> <mi>B</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>AC</mi> </msub> <msub> <mi>i</mi> <mi>C</mi> </msub> <mo>+</mo> <msub> <mi>&Psi;</mi> <mi>pm</mi> </msub> <mo>)</mo> </mrow> </mrow> </math>

<math> <mrow> <msub> <mi>U</mi> <mi>B</mi> </msub> <mo>=</mo> <msub> <mi>Ri</mi> <mi>B</mi> </msub> <mo>+</mo> <mfrac> <mi>d</mi> <mi>dt</mi> </mfrac> <mrow> <mo>(</mo> <msub> <mi>L</mi> <mi>B</mi> </msub> <msub> <mi>i</mi> <mi>B</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>BA</mi> </msub> <msub> <mi>i</mi> <mi>A</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>BC</mi> </msub> <msub> <mi>i</mi> <mi>C</mi> </msub> <mo>+</mo> <msub> <mi>&Psi;</mi> <mi>pm</mi> </msub> <mo>)</mo> </mrow> </mrow> </math>

<math> <mrow> <msub> <mi>U</mi> <mi>C</mi> </msub> <mo>=</mo> <msub> <mi>Ri</mi> <mi>C</mi> </msub> <mo>+</mo> <mfrac> <mi>d</mi> <mi>dt</mi> </mfrac> <mrow> <mo>(</mo> <msub> <mi>L</mi> <mi>C</mi> </msub> <msub> <mi>i</mi> <mi>C</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>CA</mi> </msub> <msub> <mi>i</mi> <mi>A</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>CB</mi> </msub> <msub> <mi>i</mi> <mi>B</mi> </msub> <mo>+</mo> <msub> <mi>&Psi;</mi> <mi>pm</mi> </msub> <mo>)</mo> </mrow> </mrow> </math>

wherein: u shape_A、U_BAnd U_CIs a phase voltage i_A、i_BAnd i_CIs a phase current, L_A、L_BAnd L_CFor self-induction, M_AB、M_BA、M_AC、M_CA、M_BCAnd M_CBFor mutual inductance, Ψ_pmThe rotor is a winding permanent magnet flux linkage, when the rotor rotates, the flux of the winding permanent magnet flux linkage changes along with the angle, R is the phase resistance value of the motor, t is time, and theta is an electrical angle;

a2: when the rotor position angle is a, the winding permanent magnet flux linkage is as follows:

<math> <mrow> <msub> <mi>&Psi;</mi> <mi>pm</mi> </msub> <mo>=</mo> <mi>N</mi> <msubsup> <mo>&Integral;</mo> <mrow> <mo>-</mo> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>a</mi> </mrow> <mrow> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>a</mi> </mrow> </msubsup> <mi>B</mi> <mrow> <mo>(</mo> <mi>&theta;</mi> <mo>)</mo> </mrow> <mi>Sd&theta;</mi> </mrow> </math>

n is the number of turns of the winding, B (theta) is the radial air gap flux density distribution of the rotor permanent magnet, S is the area enclosed by the winding on the surface of the inner diameter of the stator,

a3: the back electromotive force of the high-power-density motor is as follows:

<math> <mrow> <msub> <mi>e</mi> <mi>A</mi> </msub> <mo>=</mo> <mfrac> <mi>d</mi> <mi>dt</mi> </mfrac> <mi>NS</mi> <msubsup> <mo>&Integral;</mo> <mrow> <mo>-</mo> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>&theta;</mi> </mrow> <mrow> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>&theta;</mi> </mrow> </msubsup> <mi>B</mi> <mrow> <mo>(</mo> <mi>x</mi> <mo>)</mo> </mrow> <mi>Sdx</mi> <mo>=</mo> <mi>NSw</mi> <mo>[</mo> <mi>B</mi> <mrow> <mo>(</mo> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>&theta;</mi> <mo>)</mo> </mrow> <mo>-</mo> <mi>B</mi> <mrow> <mo>(</mo> <mo>-</mo> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>&theta;</mi> <mo>)</mo> </mrow> <mo>]</mo> </mrow> </math>

wherein x is the rotor position;

a4: the high power density motor adopts Y type connection, and the winding current is as follows: i.e. i_A+i_B+i_C＝0，

A5: the line voltage equation of the high power density motor is as follows:

$\left[\begin{array}{c}{U}_{\mathrm{AB}}\\ U_{\mathrm{BC}}\\ U_{\mathrm{CA}}\end{array}\right]=\left[\begin{array}{ccc}R& -R& 0\\ 0& R& -R\\ -R& 0& R\end{array}\right]\left[\begin{array}{c}{i}_A\\ i_B\\ i_C\end{array}\right]+\left[\begin{array}{ccc}L-M& M-L& 0\\ 0& L-M& M-L\\ M-L& 0& L-M\end{array}\right]\frac{d}{\mathrm{dt}}\left[\begin{array}{c}{i}_A\\ i_B\\ i_C\end{array}\right]+\left[\begin{array}{c}{e}_A-e_B\\ e_B-e_C\\ e_C-e_A\end{array}\right]$

wherein e is_A、e_BAnd e_CTo counter-potential, U_AB、U_BCAnd U_CAIs winding voltage, L is winding self inductance, and M is winding mutual inductance;

a6: the high power density motor works in a 120-degree conduction working mode, and the obtained voltage equation is as follows:

$U_{\mathrm{AB}}=2\mathrm{Ri}+2(L-M)\frac{\mathrm{di}}{\mathrm{dt}}+{2e}_A$

the torque equation is: t is_e＝K_Ti

Wherein K_TI is a steady-state phase current,

a7: the motion equation of the high power density motor is as follows:

in the formula T_LIs the load torque, J is the moment of inertia of the rotor, B_vIs viscous friction coefficient, omega is mechanical angular velocity, T_eIs the electromagnetic torque of the motor.

Preferably, step B further comprises:

b1: the micro-nano satellite flight attitude control device adopts current loop and rotating speed loop double closed loop control, the difference between a rotating speed signal and a given control quantity is selected by a control system as a rotating speed error E, the rotating speed error change rate is EC,

the fuzzy set corresponding to the rotating speed error E is as follows:

A＝[NB NM NS ZO PS PM PB]

the fuzzy set corresponding to the rotating speed error change rate EC is as follows:

B＝[NB NM NS ZO PS PM PB]

the fuzzy variables NB, NM, NS, ZO, PS, PM, and PB represent negative big, negative middle, negative small, zero, positive small, middle, and positive big, respectively,

fuzzy subsets

C＝{NB NM NS ZO PS PM PB}

B2: the fuzzy self-adaptive PI controller is a controller formed by combining a PI controller and a fuzzy self-adaptive controller, and equivalently and real-timely corrects the intermediate frequency bandwidth h and the minimum resonance peak value M of the control system by adjusting PI parameters_minThe relationship between the fuzzy adaptive PI controller output and the input fuzzy set is:

when the blur is inputAfter a variable, ternary fuzzy relation between output and inputComprises the following steps:

<math> <mrow> <mover> <mi>R</mi> <mo>~</mo> </mover> <mo>=</mo> <mrow> <munder> <mrow> <mo>&cup;</mo> <mi></mi> </mrow> <mi>k</mi> </munder> <mo>[</mo> <msup> <mrow> <mo>(</mo> <mover> <mi>A</mi> <mo>~</mo> </mover> <mo>&times;</mo> <mover> <mi>B</mi> <mo>~</mo> </mover> <mo>)</mo> </mrow> <mi>T</mi> </msup> </mrow> <mo>&times;</mo> <msub> <mover> <mi>C</mi> <mo>~</mo> </mover> <mi>k</mi> </msub> <mo>]</mo> </mrow> </math>

wherein,is a fuzzy subset of the domain of the rotational speed error EFuzzy subset on discourse of rotation speed error change rate ECIs the fuzzy adaptive PI controller output, whereinBy fuzzy relation matrixForming n multiplied by m vectors, wherein n and m are respectively the number of elements of a discourse domain, and T is the transposition of a matrix formed by fuzzy outputs corresponding to the input fuzzy sets A and B;

b3: giving a rotation speed instruction of the micro-nano satellite flight attitude control device, and obtaining the rotation speed error and the change rate of the rotation speed error through a feedback link to obtain the delta K of the fuzzy self-adaptive PI controller_pAnd Δ K_iThe corresponding output fuzzy set is then used to output the fuzzy set,

wherein, "omicron" is a cartesian product operation;

b4: defuzzifying the result obtained by fuzzy inference to obtain accurate control quantity, obtaining the accurate control quantity by a gravity center method,

<math> <mrow> <mi>y</mi> <mo>=</mo> <mfrac> <mrow> <munderover> <mi>&Sigma;</mi> <mrow> <mi>L</mi> <mo>=</mo> <mn>1</mn> </mrow> <mi>M</mi> </munderover> <mover> <mi>y</mi> <mo>&OverBar;</mo> </mover> <mo>[</mo> <msubsup> <mi>&mu;</mi> <mi>B</mi> <mi>L</mi> </msubsup> <mrow> <mo>(</mo> <msup> <mover> <mi>y</mi> <mo>&OverBar;</mo> </mover> <mi>L</mi> </msup> <mo>)</mo> </mrow> <mo>]</mo> </mrow> <mrow> <munderover> <mi>&Sigma;</mi> <mrow> <mi>L</mi> <mo>=</mo> <mn>1</mn> </mrow> <mi>M</mi> </munderover> <mo>[</mo> <msubsup> <mi>&mu;</mi> <mi>B</mi> <mi>L</mi> </msubsup> <mrow> <mo>(</mo> <msup> <mover> <mi>y</mi> <mo>&OverBar;</mo> </mover> <mi>L</mi> </msup> <mo>)</mo> </mrow> <mo>]</mo> </mrow> </mfrac> </mrow> </math>

wherein, B is the fuzzy set corresponding to the variation of the rotating speed error, y is the solution fuzzy value, L is the fuzzy subset number, M is the total number of the fuzzy subset indexes, mu is the membership function,the average value is output for the maximum degree of membership,is a membership function on a fuzzy subset L in a fuzzy set B;

b5: the control quantity finally applied to the micro-nano satellite flight attitude control device is as follows:

K_p1＝K_p2+ΔK_p3，K_i1＝K_i2+ΔK_i3

wherein, K_p1、K_p2、K_i1、K_i2Proportional and integral factors, respectively, Δ K_p3、ΔK_i3Respectively, a scale factor variation and an integral factor variation.

The method for controlling the flight attitude of the micro-nano satellite has the advantages of self-adaptive absorption of various disturbance torques in an in-orbit period, ultrahigh-speed response, high accuracy, zero tracking error, self-adaptive resistance to external disturbance and the like.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a structural diagram of a micro/nano satellite flight attitude control device according to an embodiment of the invention;

FIG. 2 is a structural diagram of an optimal flywheel body of the micro/nano satellite flight attitude control device according to the embodiment of the invention;

FIG. 3 is a structural diagram of a fuzzy adaptive PI controller of a micro/nano satellite flight attitude control device according to an embodiment of the present invention;

FIG. 4 is a flow chart of a method for controlling a flight attitude of a micro/nano satellite according to an embodiment of the invention;

FIG. 5 is a schematic diagram of a method for controlling a flight attitude of a micro/nano satellite according to an embodiment of the invention;

FIG. 6 is a fuzzy self-adaptive PI controller diagram of a micro/nano satellite flight attitude control method according to an embodiment of the invention;

FIG. 7 is a response curve diagram of a fuzzy adaptive PI controller of a micro/nano satellite flight attitude control method according to an embodiment of the invention;

FIG. 8 is a control surface diagram of a fuzzy adaptive PI controller of a micro/nano satellite flight attitude control method according to an embodiment of the invention;

FIG. 9 is a simulation diagram of a method for controlling a flight attitude of a micro/nano satellite according to an embodiment of the invention;

FIG. 10 is a response curve diagram of a flywheel body of the method for controlling the flight attitude of the micro/nano satellite according to the embodiment of the invention;

FIG. 11 is a steady-state error diagram of a flywheel body of the method for controlling the flight attitude of the micro/nano satellite according to the embodiment of the invention;

fig. 12 is a diagram of a disturbance suppression effect of a flywheel body of the micro/nano satellite flight attitude control method according to the embodiment of the invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

As shown in fig. 1, a structure diagram of a micro/nano satellite flight attitude control apparatus according to an embodiment of the present invention includes a fuzzy adaptive PI controller 100, a driver 200, a high power density motor 300, and a flywheel body 400, where:

the fuzzy self-adaptive PI controller 100 is used for sending an adjustable duty ratio pulse signal to the driver 200, the driver 200 is connected with the fuzzy self-adaptive PI controller 100 and used for converting the adjustable duty ratio pulse signal into an angular momentum control signal and sending the angular momentum control signal to the high-power density motor 300, and the driver 200 is also used for collecting a torque voltage signal and a protection voltage signal of the high-power density motor 300 and sending the torque voltage signal and the protection voltage signal to the fuzzy self-adaptive PI controller 100.

According to the change of various disturbance factors such as gravity gradient moment, solar wind radiation moment, thermal radiation moment caused by asymmetric temperature of each part of a star and the like when the micro-nano satellite flies around the orbit, and unpredictable unexpected disturbance moment, operation temperature and nonlinear change of friction moment, the fuzzy self-adaptive PI controller 100 and the driver 200 absorb the disturbance moment, angular momentum control signals are controlled to be output in a fuzzy self-adaptive mode, and the star attitude is stabilized in real time.

The high power density motor 300 is connected with the driver 200 and used for controlling the flywheel body 400 according to the angular momentum control signal, so that the volume and the mass are reduced, and meanwhile, enough power is kept, and the flywheel body 400 is connected with the high power density motor 300 and used for outputting variable angular momentum to control the flight attitude of the micro-nano satellite under the driving of the high power density motor 300. The flywheel body 400 is driven by the high power density motor 300 to adaptively absorb various disturbance torques during the in-orbit period.

As shown in fig. 2, a structural diagram of an optimal flywheel body 400 of a micro/nano satellite flight attitude control device according to an embodiment of the present invention is shown.

In order to meet the requirements of the micro-nano satellite on the configuration, size, mass and power consumption of the flywheel body 400, the size of the flywheel body 400 is reduced as much as possible, the inertia/mass ratio of the flywheel body 400 is improved, and the configuration, size, mass and other parameters of the flywheel body 400 are optimally designed. Under the above constraint conditions, the flywheel body 400 adopts a disc structure as shown in fig. 2, which ensures the strength of the flywheel body 400 to make the mass of the flywheel body 400 far from the rotating shaft, thereby improving the inertia/mass ratio and realizing the maximum rotational inertia with small volume and small mass. Where h denotes the height of the flywheel body 400, t denotes the thickness of the chassis of the flywheel body 400, and R denote the outer diameter and inner diameter of the flywheel body 400, respectively.

As shown in fig. 3, a structural diagram of a fuzzy adaptive PI controller 100 of a micro/nano satellite flight attitude control device according to an embodiment of the present invention includes: a tachometer module 110, a comparator 120, an adaptive tachometer controller 130, a processor 140, an adaptive motor controller 150, a comparison filter 160, and a current controller 170.

The speed measuring module 110 is connected to the high power density motor 300, and is configured to collect a rotation speed signal of the high power density motor 300 and send the rotation speed signal to the comparator 120.

The comparator 120 is connected to the speed measurement module 110, and configured to compare the rotation speed signal with a given control amount to obtain a rotation speed error, and send the rotation speed error to the adaptive rotation speed controller 130.

The adaptive rpm controller 130 is connected to the comparator 120, and is configured to convert the rpm error into an rpm control amount, and send the rpm control amount to the processor 140.

The adaptive motor controller 150 is connected to the high power density motor 300 and the driver 200, respectively, and is configured to collect a motor torque characteristic current of the high power density motor 300, convert the motor torque characteristic current into a torque current control quantity, and send the torque current control quantity to the processor 140.

The processor 140 is connected to the adaptive rpm controller 130 and the adaptive motor controller 150, and converts the rpm control amount and the torque current control amount into voltage signal control amounts and sends them to the comparison filter 160.

The comparison filter 160 is connected to the driver 200 and the processor 140, and is configured to compare the torque voltage signal, the protection voltage signal, and the voltage signal control amount to obtain a comparison voltage signal, and send the comparison voltage signal to the current controller 170.

The current controller 170 is connected to the adaptive motor controller 150 and the comparison filter 160, and converts the comparison voltage signal into a comparison current signal, and transmits the comparison current signal to the adaptive motor controller 150.

Adaptive motor controller 150 converts the comparison current signal to an adjustable duty cycle pulse signal and sends it to driver 200.

According to the micro-nano satellite flight attitude control device disclosed by the embodiment of the invention, the attitude of the micro-nano satellite can be quickly stabilized after the micro-nano satellite is separated from a rocket and enters the orbit, so that the micro-nano satellite can keep stable attitude and make necessary attitude maneuver under the environment of various external disturbance moments during subsequent flight.

As shown in fig. 4, a flowchart of a method for controlling a flight attitude of a micro/nano satellite according to an embodiment of the present invention is shown, and a schematic diagram of the method for controlling a flight attitude of a micro/nano satellite according to an embodiment of the present invention shown in fig. 5 is combined, and the method includes the following steps:

a: and establishing a mathematical model of the micro-nano satellite flight attitude control device.

Step a further comprises:

the micro-nano satellite flight attitude control device is composed of a fuzzy self-adaptive PI controller, a driver, a high power density motor and a flywheel body, wherein when the high power density motor is preferably a Faul Harber-2036B permanent magnet brushless direct current motor:

a1: the voltage of each phase of the high-power-density motor is equal to the sum of the resistance voltage drop of the winding and the induced potential of the winding, and after reasonable assumption is made, the three-phase voltage of the winding A, B, C can be expressed as:

<math> <mrow> <msub> <mi>U</mi> <mi>A</mi> </msub> <mo>=</mo> <msub> <mi>Ri</mi> <mi>A</mi> </msub> <mo>+</mo> <mfrac> <mi>d</mi> <mi>dt</mi> </mfrac> <mrow> <mo>(</mo> <msub> <mi>L</mi> <mi>A</mi> </msub> <msub> <mi>i</mi> <mi>A</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>AB</mi> </msub> <msub> <mi>i</mi> <mi>B</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>AC</mi> </msub> <msub> <mi>i</mi> <mi>C</mi> </msub> <mo>+</mo> <msub> <mi>&Psi;</mi> <mi>pm</mi> </msub> <mo>)</mo> </mrow> </mrow> </math>

<math> <mrow> <msub> <mi>U</mi> <mi>B</mi> </msub> <mo>=</mo> <msub> <mi>Ri</mi> <mi>B</mi> </msub> <mo>+</mo> <mfrac> <mi>d</mi> <mi>dt</mi> </mfrac> <mrow> <mo>(</mo> <msub> <mi>L</mi> <mi>B</mi> </msub> <msub> <mi>i</mi> <mi>B</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>BA</mi> </msub> <msub> <mi>i</mi> <mi>A</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>BC</mi> </msub> <msub> <mi>i</mi> <mi>C</mi> </msub> <mo>+</mo> <msub> <mi>&Psi;</mi> <mi>pm</mi> </msub> <mo>)</mo> </mrow> </mrow> </math>

<math> <mrow> <msub> <mi>U</mi> <mi>C</mi> </msub> <mo>=</mo> <msub> <mi>Ri</mi> <mi>C</mi> </msub> <mo>+</mo> <mfrac> <mi>d</mi> <mi>dt</mi> </mfrac> <mrow> <mo>(</mo> <msub> <mi>L</mi> <mi>C</mi> </msub> <msub> <mi>i</mi> <mi>C</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>CA</mi> </msub> <msub> <mi>i</mi> <mi>A</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>CB</mi> </msub> <msub> <mi>i</mi> <mi>B</mi> </msub> <mo>+</mo> <msub> <mi>&Psi;</mi> <mi>pm</mi> </msub> <mo>)</mo> </mrow> </mrow> </math>

wherein: u shape_A、U_BAnd U_CIs a phase voltage i_A、i_BAnd i_CIs a phase current, L_A、L_BAnd L_CFor self-induction, M_AB、M_BA、M_AC、M_CA、M_BCAnd M_CBFor mutual inductance, Ψ_pmThe rotor is a winding permanent magnet flux linkage, when the rotor rotates, the flux of the winding permanent magnet flux linkage changes along with the angle, R is the phase resistance value of the motor, t is time, and theta is an electrical angle.

A2: when the rotor position angle is a, the winding permanent magnet flux linkage is as follows:

<math> <mrow> <msub> <mi>&Psi;</mi> <mi>pm</mi> </msub> <mo>=</mo> <mi>N</mi> <msubsup> <mo>&Integral;</mo> <mrow> <mo>-</mo> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>a</mi> </mrow> <mrow> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>a</mi> </mrow> </msubsup> <mi>B</mi> <mrow> <mo>(</mo> <mi>&theta;</mi> <mo>)</mo> </mrow> <mi>Sd&theta;</mi> </mrow> </math>

n is the winding turn number, B (theta) is the radial air gap flux density distribution of the rotor permanent magnet, and S is the area enclosed by the winding on the surface of the inner diameter of the stator.

A3: the back electromotive force of the high-power density motor is as follows:

<math> <mrow> <mrow> <msub> <mi>e</mi> <mi>A</mi> </msub> <mo>=</mo> <mfrac> <mi>d</mi> <mi>dt</mi> </mfrac> <mi>NS</mi> <msubsup> <mo>&Integral;</mo> <mrow> <mo>-</mo> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>&theta;</mi> </mrow> <mrow> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>&theta;</mi> </mrow> </msubsup> <mi>B</mi> <mrow> <mo>(</mo> <mi>x</mi> <mo>)</mo> </mrow> <mi>Sdx</mi> <mo>=</mo> <mi>NSw</mi> <mo>[</mo> <mi>B</mi> <mrow> <mo>(</mo> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>&theta;</mi> <mo>)</mo> </mrow> <mo>-</mo> <mi>B</mi> <mrow> <mo>(</mo> <mo>-</mo> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>&theta;</mi> <mo>)</mo> </mrow> <mo>]</mo> </mrow> <mo>.</mo> </mrow> </math>

where x is the rotor position.

A4: the high power density motor Faul Harber-2036B adopts Y-shaped connection, and the winding current is as follows: i.e. i_A+i_B+i_C＝0。

A5: the line voltage equation of the high power density motor is as follows:

$\left[\begin{array}{c}{U}_{\mathrm{AB}}\\ U_{\mathrm{BC}}\\ U_{\mathrm{CA}}\end{array}\right]=\left[\begin{array}{ccc}R& -R& 0\\ 0& R& -R\\ -R& 0& R\end{array}\right]\left[\begin{array}{c}{i}_A\\ i_B\\ i_C\end{array}\right]+\left[\begin{array}{ccc}L-M& M-L& 0\\ 0& L-M& M-L\\ M-L& 0& L-M\end{array}\right]\frac{d}{\mathrm{dt}}\left[\begin{array}{c}{i}_A\\ i_B\\ i_C\end{array}\right]+\left[\begin{array}{c}{e}_A-e_B\\ e_B-e_C\\ e_C-e_A\end{array}\right].$

wherein e is_A、e_BAnd e_CTo counter-potential, U_AB、U_BCAnd U_CAIs the winding voltage, L is the winding self inductance, and M is the winding mutual inductance.

A6: the high power density motor works in a 120-degree conduction working mode, and the obtained voltage equation is as follows:

$U_{\mathrm{AB}}=2\mathrm{Ri}+2(L-M)\frac{\mathrm{di}}{\mathrm{dt}}+{2e}_A$

the torque equation is: t is_e＝K_Ti

Wherein K_TFor the high power density motor torque coefficient, i is the steady state phase current.

A7: the motion equation of the high-power-density motor is as follows:

in the formula T_LIs the load torque, J is the rotor moment of inertia, B_vIs viscous friction coefficient, omega is mechanical angular velocity, T_eIs the electromagnetic torque of the motor.

From the above analysis, when the load torque T is obtained_LThe viscous friction coefficient B is changed or changed along with the change of the rotating speed and the change of the temperature_vAlso exhibit non-linear variations.

Further, the UC1625 motor fuzzy adaptive PI controller and driver model, analyzed, may be equivalent to a first-order inertial link:

$G\left(s\right)=\frac{K}{\mathrm{Ts}+1}$

b: and designing the control quantity of a fuzzy self-adaptive PI controller of the micro-nano satellite flight attitude control device.

The micro-nano satellite flight attitude control device adopts current loop and rotating speed loop double closed loop control. For the permanent magnet brushless dc motor used in the high power density motor of the embodiment of the present invention, the controlled object is a nonlinear, multivariable, strongly coupled model. The device works under the action of disturbance, the traditional PI controller is difficult to achieve an ideal effect, and the self characteristics and the working environment of the micro-nano satellite flight attitude control device determine that a self-adaptive controller for dynamically adjusting parameters according to the change of the working environment is needed.

The fuzzy self-adaptive PI controller is a controller formed by combining the fuzzy self-adaptive PI controller based on the PI controller. Correcting the medium frequency bandwidth h and the minimum resonance peak value M of the momentum wheel system in real time through adjusting PI parameter equivalence_minAnd the dynamic characteristic of a large inertia ratio system is improved. The method is suitable for the control environment with high nonlinearity, large parameter variation along with the working point, serious cross coupling, strong interference of environmental factors and changeable or uncertain mathematical model. The fuzzy adaptive PI controller is shown in fig. 6.

B1: the micro-nano satellite flight attitude control device adopts current loop and rotating speed loop double closed loop control, the difference between a rotating speed signal and a given control quantity selected by a control system is a rotating speed error E, the rotating speed error change rate is EC, and the discourse domain of the rotating speed error E is [ -6000,6000 [ -]Quantization factor K of the rotational speed error E_E0.001083, the discourse domain of the error change rate EC of the rotating speed is [ -40000,40000 ]]Quantification factor K of the rate of change of rotation speed error EC_EC＝0.0001625，

The fuzzy set corresponding to the rotating speed error E is as follows:

A＝[NB NM NS ZO PS PM PB]

the fuzzy set corresponding to the rotating speed error change rate EC is as follows:

B＝[NB NM NS ZO PS PM PB]

the fuzzy variables NB, NM, NS, ZO, PS, PM, and PB represent negative big, negative middle, negative small, zero, positive small, middle, and positive big, respectively,

output delta K of fuzzy adaptive PI controller_pAnd Δ K_iAll domains on the fuzzy set are

{-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6}

Fuzzy subsets

C＝{NB NM NS ZO PS PM PB}

As shown in fig. 7, which is a response curve diagram of a fuzzy adaptive PI controller of the method for controlling the flight attitude of the micro/nano satellite according to the embodiment of the present invention, in order to improve the dynamic performance and the steady-state performance of the system, the proportional coefficient K of the response curve in the OA section is shown_pShould be large first and small second, integral coefficient K_iIt should be small first and then large in order for the output to approach steady state faster. AB section proportionality coefficient K_pShould be gradually increased to eliminate the error as soon as possible, the integral coefficient K_iThe slow decrease should prevent the integration saturation. Proportional coefficient K of BC section_pShould be gradually reduced as the error is smaller, the integral coefficient should be increased. CD section proportionality coefficient K_pGradually increasing, integral coefficient K_iGradually decreases. Proportional coefficient K of DE section_pShould be gradually decreased and the integration coefficient should be gradually increased. Finally K_pAnd K_iAnd tends to be stable.

B2: the fuzzy self-adaptive PI controller is a controller formed by combining a PI controller and a fuzzy self-adaptive controller, and the medium frequency bandwidth h and the minimum resonance peak value M of a control system are equivalently corrected in real time by adjusting PI parameters_minThe relationship between the output of the fuzzy adaptive PI controller and the input fuzzy set is:

after fuzzy variables are input, the ternary fuzzy relation between output and inputComprises the following steps:

<math> <mrow> <mover> <mi>R</mi> <mo>~</mo> </mover> <mo>=</mo> <mrow> <munder> <mrow> <mo>&cup;</mo> <mi></mi> </mrow> <mi>k</mi> </munder> <mo>[</mo> <msup> <mrow> <mo>(</mo> <mover> <mi>A</mi> <mo>~</mo> </mover> <mo>&times;</mo> <mover> <mi>B</mi> <mo>~</mo> </mover> <mo>)</mo> </mrow> <mi>T</mi> </msup> </mrow> <mo>&times;</mo> <msub> <mover> <mi>C</mi> <mo>~</mo> </mover> <mi>k</mi> </msub> <mo>]</mo> </mrow> </math>

wherein,is a fuzzy subset of the domain of the rotational speed error EFuzzy subset on discourse of rotation speed error change rate ECIs a fuzzy adaptive PI controller output, whereinBy fuzzy relation matrixAnd (3) forming n multiplied by m vectors, wherein n and m are respectively the number of elements of the domain, and T is the transposition of the input fuzzy sets A and B corresponding to the fuzzy output forming matrix.

B3: given a rotation speed instruction of a micro-nano satellite flight attitude control device, after a feedback link obtains a rotation speed error and a rotation speed error change rate, a fuzzy self-adaptive PI controller delta K can be obtained_pAnd Δ K_iThe corresponding output fuzzy set is then used to output the fuzzy set,

wherein, "omicron" is cartesian product operation, as shown in fig. 8, is a control surface diagram of the fuzzy adaptive PI controller of the method for controlling the flight attitude of the micro/nano satellite according to the embodiment of the present invention.

B4: defuzzifying the result obtained by fuzzy inference to obtain accurate control quantity, obtaining the accurate control quantity by gravity center method,

<math> <mrow> <mi>y</mi> <mo>=</mo> <mfrac> <mrow> <munderover> <mi>&Sigma;</mi> <mrow> <mi>L</mi> <mo>=</mo> <mn>1</mn> </mrow> <mi>M</mi> </munderover> <mover> <mi>y</mi> <mo>&OverBar;</mo> </mover> <mo>[</mo> <msubsup> <mi>&mu;</mi> <mi>B</mi> <mi>L</mi> </msubsup> <mrow> <mo>(</mo> <msup> <mover> <mi>y</mi> <mo>&OverBar;</mo> </mover> <mi>L</mi> </msup> <mo>)</mo> </mrow> <mo>]</mo> </mrow> <mrow> <munderover> <mi>&Sigma;</mi> <mrow> <mi>L</mi> <mo>=</mo> <mn>1</mn> </mrow> <mi>M</mi> </munderover> <mo>[</mo> <msubsup> <mi>&mu;</mi> <mi>B</mi> <mi>L</mi> </msubsup> <mrow> <mo>(</mo> <msup> <mover> <mi>y</mi> <mo>&OverBar;</mo> </mover> <mi>L</mi> </msup> <mo>)</mo> </mrow> <mo>]</mo> </mrow> </mfrac> </mrow> </math>

wherein, B is the fuzzy set corresponding to the variation of the rotating speed error, y is the solution fuzzy value, L is the fuzzy subset number, M is the total number of the fuzzy subset indexes, mu is the membership function,the maximum degree of membership outputs an average value,is a membership function on the fuzzy subset L in the fuzzy set B.

B5: the control quantity finally applied to the micro-nano satellite flight attitude control device is as follows:

K_p＝K_p+ΔK_p，K_i＝K_i+ΔK_i，

wherein, K_p、K_iProportional and integral factors, respectively, Δ K_P、ΔK_iRespectively, a scale factor variation and an integral factor variation.

As shown in fig. 9, which is a simulation diagram of a method for controlling a flight attitude of a micro/nano satellite according to an embodiment of the present invention, for a micro momentum wheel system of a nano satellite, parameters are as follows: high power density motor rotor moment of inertia J1.95 g cm²Flywheel moment of inertia J ═ 1.34 × 10^-4kg·m²The phase resistance R of the high power density motor is 3.4 omega, and the self-inductance L of the high power density motor_A＝L_B＝L_C148uH, Faul Harber-2036B speed constant k_n1506rpm/V, EMF (electromotive force) constant k_E0.664mV/rpm, high power density motor torque coefficient k_T6.34mNm/A, mechanical time constant τ_m16ms, which is the time required for the high power density motor to rotate 63% of the rated speed at rated voltage and no load, the driver equivalent time constant τ is 0.0148 ms.

As shown in fig. 9, the NS-2 flywheel body has a working range of 0 to 6000rpm, and when the given rotation speed control amount is 6024rpm from the time point of t being 5s, the flywheel body response curve is as shown in fig. 10, the curve (i) is a flywheel body step response curve under no feedback control, the curve (ii) is a flywheel body step response curve using a conventional PI controller, the curve (iii) is a flywheel body step response curve using a fuzzy adaptive PI controller, and the flywheel body response time using the fuzzy adaptive PI controller is shorter and smaller than that of the conventional PI controller. As shown in fig. 11, the rotation speed at 7 seconds is 6024.1rpm, the steady state error at this time is 0.00166%, the design requirement of the steady state error 1/6000rpm is reached, and the response time is about 0.2 s. Applying a disturbance signal at the moment of 7.1s, the rotating speed of the flywheel body fluctuates due to disturbance, and the fuzzy self-adaptive PI controller rapidly adjusts the system when the disturbance occurs, so that the disturbed output amplitude tends to be stable at a higher speed compared with the traditional PI controller, the simulation effect is shown in figure 12, wherein a curve (i) is a flywheel body response curve when the traditional PI controller is adopted for disturbance, and a curve (ii) is a flywheel body response curve when the fuzzy self-adaptive PI controller is adopted for disturbance.

According to the method for controlling the flight attitude of the micro/nano satellite, the fuzzy self-adaptive PI controller can enable the flywheel body to respond ultrafast, the response time is less than or equal to 0.2s, meanwhile, an ultra-small steady-state error is obtained, the steady-state error is 0.00166%, and the design requirements of high interference resistance, high precision and the like are met.

According to the method for controlling the flight attitude of the micro-nano satellite, the micro-nano satellite can be separated from a rocket and enters the orbit to quickly stabilize the attitude, so that the micro-nano satellite can keep the attitude stable and perform necessary attitude maneuver under the environment of various external disturbance moments during subsequent flight.

Any process or method descriptions in flow charts or otherwise described herein may be understood as representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or steps of the process, and alternate implementations are included within the scope of the preferred embodiment of the present invention in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the present invention.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made in the above embodiments by those of ordinary skill in the art without departing from the principle and spirit of the present invention.

Claims (4)

1. A micro-nano satellite flight attitude control device is characterized by comprising: fuzzy self-adaptation PI controller, driver, high power density motor and flywheel body, wherein:

the fuzzy self-adaptive PI controller is used for sending an adjustable duty ratio pulse signal to the driver;

the driver is connected with the fuzzy self-adaptive PI controller and used for converting the adjustable duty ratio pulse signal into an angular momentum control signal, sending the angular momentum control signal to the high-power-density motor, collecting a torque voltage signal and a protection voltage signal of the high-power-density motor and sending the torque voltage signal and the protection voltage signal to the fuzzy self-adaptive PI controller;

the high-power density motor is connected with the driver and used for controlling the flywheel body according to the angular momentum control signal;

the flywheel body is connected with the high-power-density motor and used for outputting variable angular momentum under the driving of the high-power-density motor to control the flight attitude of the micro-nano satellite.

2. A micro-nano satellite flight attitude control device according to claim 1, wherein the fuzzy adaptive PI controller comprises: speed measuring module, comparator, self-adaptation rotational speed controller, treater, self-adaptation motor controller, comparison filter and current controller, wherein:

the speed measuring module is connected with the high-power-density motor and used for acquiring a rotating speed signal of the high-power-density motor and sending the rotating speed signal to the comparator;

the comparator is connected with the speed measuring module and used for comparing the rotating speed signal with a given control quantity to obtain a rotating speed error and sending the rotating speed error to the self-adaptive rotating speed controller;

the self-adaptive rotating speed controller is connected with the comparator and used for converting the rotating speed error into a rotating speed control quantity and sending the rotating speed control quantity to the processor;

the self-adaptive motor controller is respectively connected with the high-power-density motor and the driver and is used for collecting motor torque characteristic current of the high-power-density motor, converting the motor torque characteristic current into torque current control quantity and sending the torque current control quantity to the processor;

the processor is connected with the self-adaptive rotating speed controller and the self-adaptive motor controller and is used for converting the rotating speed control quantity and the torque current control quantity into voltage signal control quantity and sending the voltage signal control quantity to the comparison filter;

the comparison filter is connected with the driver and the processor and used for comparing the torque voltage signal, the protection voltage signal and the voltage signal control quantity to obtain a comparison voltage signal and sending the comparison voltage signal to the current controller;

the current controller is connected with the self-adaptive motor controller and the comparison filter, and is used for converting the comparison voltage signal into a comparison current signal and sending the comparison current signal to the self-adaptive motor controller;

and the self-adaptive motor controller converts the comparison current signal into the pulse signal with the adjustable duty ratio and sends the pulse signal to the driver.

3. A micro-nano satellite flight attitude control method is characterized by being applied to the micro-nano satellite flight attitude control device of any one of claims 1-2, and comprising the following steps of:

a: establishing a mathematical model of the micro-nano satellite flight attitude control device, wherein the step A further comprises the following steps: the micro/nano satellite flight attitude control device consists of a fuzzy self-adaptive PI controller, a driver, a high-power density motor and a flywheel body;

a1: the voltage of each phase of the high-power-density motor is equal to the sum of the resistance voltage drop of the winding and the induced potential of the winding, and after reasonable assumption is made, the three-phase voltage of the winding A, B, C can be expressed as:

<math> <mrow> <msub> <mi>U</mi> <mi>A</mi> </msub> <mo>=</mo> <msub> <mi>Ri</mi> <mi>A</mi> </msub> <mo>+</mo> <mfrac> <mi>d</mi> <mi>dt</mi> </mfrac> <mrow> <mo>(</mo> <msub> <mi>L</mi> <mi>A</mi> </msub> <msub> <mi>i</mi> <mi>A</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>AB</mi> </msub> <msub> <mi>i</mi> <mi>B</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>AC</mi> </msub> <msub> <mi>i</mi> <mi>C</mi> </msub> <mo>+</mo> <msub> <mi>&Psi;</mi> <mi>pm</mi> </msub> <mo>)</mo> </mrow> </mrow> </math>

<math> <mrow> <msub> <mi>U</mi> <mi>B</mi> </msub> <mo>=</mo> <msub> <mi>Ri</mi> <mi>B</mi> </msub> <mo>+</mo> <mfrac> <mi>d</mi> <mi>dt</mi> </mfrac> <mrow> <mo>(</mo> <msub> <mi>L</mi> <mi>B</mi> </msub> <msub> <mi>i</mi> <mi>B</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>BA</mi> </msub> <msub> <mi>i</mi> <mi>A</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>BC</mi> </msub> <msub> <mi>i</mi> <mi>C</mi> </msub> <mo>+</mo> <msub> <mi>&Psi;</mi> <mi>pm</mi> </msub> <mo>)</mo> </mrow> </mrow> </math>

<math> <mrow> <msub> <mi>U</mi> <mi>C</mi> </msub> <mo>=</mo> <msub> <mi>Ri</mi> <mi>C</mi> </msub> <mo>+</mo> <mfrac> <mi>d</mi> <mi>dt</mi> </mfrac> <mrow> <mo>(</mo> <msub> <mi>L</mi> <mi>C</mi> </msub> <msub> <mi>i</mi> <mi>C</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>CA</mi> </msub> <msub> <mi>i</mi> <mi>A</mi> </msub> <mo>+</mo> <msub> <mi>M</mi> <mi>CB</mi> </msub> <msub> <mi>i</mi> <mi>B</mi> </msub> <mo>+</mo> <msub> <mi>&Psi;</mi> <mi>pm</mi> </msub> <mo>)</mo> </mrow> </mrow> </math>

wherein: u shape_A、U_BAnd U_CIs a phase voltage i_A、i_BAnd i_CIs a phase current, L_A、L_BAnd L_CFor self-induction, M_AB、M_BA、M_AC、M_CA、M_BCAnd M_CBFor mutual inductance, Ψ_pmThe rotor is a winding permanent magnet flux linkage, when the rotor rotates, the flux of the winding permanent magnet flux linkage changes along with the angle, R is the phase resistance value of the motor, and t is time;

a2: when the rotor position angle is a, the winding permanent magnet flux linkage is as follows:

<math> <mrow> <msub> <mi>&Psi;</mi> <mi>pm</mi> </msub> <mo>=</mo> <mi>N</mi> <msubsup> <mo>&Integral;</mo> <mrow> <mo>-</mo> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>a</mi> </mrow> <mrow> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>a</mi> </mrow> </msubsup> <mi>B</mi> <mrow> <mo>(</mo> <mi>&theta;</mi> <mo>)</mo> </mrow> <mi>Sd&theta;</mi> </mrow> </math>

n is the number of turns of the winding, B (theta) is the radial air gap flux density distribution of the rotor permanent magnet, S is the area enclosed by the winding on the surface of the inner diameter of the stator, and theta is the electrical angle;

a3: the back electromotive force of the high-power-density motor is as follows:

<math> <mrow> <msub> <mi>e</mi> <mi>A</mi> </msub> <mo>=</mo> <mfrac> <mi>d</mi> <mi>dt</mi> </mfrac> <mi>NS</mi> <msubsup> <mo>&Integral;</mo> <mrow> <mo>-</mo> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>&theta;</mi> </mrow> <mrow> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>&theta;</mi> </mrow> </msubsup> <mi>B</mi> <mrow> <mo>(</mo> <mi>x</mi> <mo>)</mo> </mrow> <mi>Sdx</mi> <mo>=</mo> <mi>NSw</mi> <mo>[</mo> <mi>B</mi> <mrow> <mo>(</mo> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>&theta;</mi> <mo>)</mo> </mrow> <mo>-</mo> <mi>B</mi> <mrow> <mo>(</mo> <mo>-</mo> <mfrac> <mi>&pi;</mi> <mn>2</mn> </mfrac> <mo>+</mo> <mi>&theta;</mi> <mo>)</mo> </mrow> </mrow> </math>

wherein x is the rotor position;

a4: the high power density motor adopts Y type connection, and the winding current is as follows: i.e. i_A+i_B+i_C＝0，

A5: the line voltage equation of the high power density motor is as follows:

$\left[\begin{array}{c}{U}_{\mathrm{AB}}\\ U_{\mathrm{BC}}\\ U_{\mathrm{CA}}\end{array}\right]=\left[\begin{array}{ccc}R& -R& 0\\ 0& R& -R\\ -R& 0& R\end{array}\right]\left[\begin{array}{c}{i}_A\\ i_B\\ i_C\end{array}\right]+\left[\begin{array}{ccc}L-M& M-L& 0\\ 0& L-M& M-L\\ M-L& 0& L-M\end{array}\right]\frac{d}{\mathrm{dt}}\left[\begin{array}{c}{i}_A\\ i_B\\ i_C\end{array}\right]+\left[\begin{array}{c}{e}_A-e_B\\ e_B-e_C\\ e_C-e_A\end{array}\right]$

wherein e is_A、e_BAnd e_CTo counter-potential, U_AB、U_BCAnd U_CAIs winding voltage, L is winding self inductance, and M is winding mutual inductance;

a6: the high power density motor works in a 120-degree conduction working mode, and the obtained voltage equation is as follows:

$U_{\mathrm{AB}}=2\mathrm{Ri}+2(L-M)\frac{\mathrm{di}}{\mathrm{dt}}+{2e}_A$

the torque equation is: t is_e＝K_Ti

Wherein K_TIs that it isThe torque coefficient of the high power density motor, i is the steady-state time phase current,

a7: the motion equation of the high power density motor is as follows:

in the formula T_LIs the load torque, J is the moment of inertia of the rotor, B_vIs viscous friction coefficient, omega is mechanical angular velocity, T_eIs the motor electromagnetic torque;

b: and designing the control quantity of a fuzzy self-adaptive PI controller of the micro-nano satellite flight attitude control device.

4. The method for controlling the flight attitude of the micro-nano satellite according to claim 3, wherein the step B further comprises the following steps:

b1: the micro-nano satellite flight attitude control device adopts current loop and rotating speed loop double closed loop control, the difference between a rotating speed signal and a given control quantity is selected by a control system as a rotating speed error E, the rotating speed error change rate is EC,

the fuzzy set corresponding to the rotating speed error E is as follows:

A＝[NB NM NS ZO PS PM PB]

the fuzzy set corresponding to the rotating speed error change rate EC is as follows:

B＝[NB NM NS ZO PS PM PB]

the fuzzy variables NB, NM, NS, ZO, PS, PM, and PB represent negative big, negative middle, negative small, zero, positive small, middle, and positive big, respectively,

fuzzy subsets

C＝{NB NM NS ZO PS PM PB}

B2: the fuzzy self-adaptive PI controller is a controller formed by combining a PI controller and a fuzzy self-adaptive controller, and equivalently and real-timely corrects the intermediate frequency bandwidth h and the minimum resonance peak value M of the control system by adjusting PI parameters_minThe relationship between the fuzzy adaptive PI controller output and the input fuzzy set is:

after the fuzzy variable is input, the ternary fuzzy relation R & lt- & gt between the output and the input is as follows:

<math> <mrow> <mover> <mi>R</mi> <mo>~</mo> </mover> <mo>=</mo> <munder> <mi>U</mi> <mi>k</mi> </munder> <mo>[</mo> <msup> <mrow> <mo>(</mo> <mover> <mi>A</mi> <mo>~</mo> </mover> <mo>&times;</mo> <mover> <mi>B</mi> <mo>~</mo> </mover> <mo>)</mo> </mrow> <mi>T</mi> </msup> <mo>&times;</mo> <msub> <mover> <mi>C</mi> <mo>~</mo> </mover> <mi>K</mi> </msub> <mo>]</mo> </mrow> </math>

wherein,is a fuzzy subset of the domain of the rotational speed error EFuzzy subset on discourse of rotation speed error change rate ECIs the fuzzy adaptive PI controller output, whereinBy fuzzy relation matrixForming n multiplied by m vectors, wherein n and m are respectively the number of elements of a discourse domain, and T is the transposition of a matrix formed by fuzzy outputs corresponding to the input fuzzy sets A and B;

b3: giving a rotation speed instruction of the micro-nano satellite flight attitude control device, and obtaining the rotation speed error and the change rate of the rotation speed error through a feedback link to obtain the delta K of the fuzzy self-adaptive PI controller_pAnd Δ K_iThe corresponding output fuzzy set is then used to output the fuzzy set,

wherein, "omicron" is a cartesian product operation;

b4: defuzzifying the result obtained by fuzzy inference to obtain accurate control quantity, obtaining the accurate control quantity by a gravity center method,

<math> <mrow> <mi>y</mi> <mo>=</mo> <mfrac> <mrow> <munderover> <mi>&Sigma;</mi> <mrow> <mi>L</mi> <mo>=</mo> <mn>1</mn> </mrow> <mi>M</mi> </munderover> <mover> <mi>y</mi> <mo>&OverBar;</mo> </mover> <mo>[</mo> <msubsup> <mi>&mu;</mi> <mi>B</mi> <mi>L</mi> </msubsup> <mrow> <mo>(</mo> <msup> <mover> <mi>y</mi> <mo>&OverBar;</mo> </mover> <mi>L</mi> </msup> <mo>)</mo> </mrow> <mo>]</mo> </mrow> <mrow> <munderover> <mi>&Sigma;</mi> <mrow> <mi>L</mi> <mo>=</mo> <mn>1</mn> </mrow> <mi>M</mi> </munderover> <mo>[</mo> <msubsup> <mi>&mu;</mi> <mi>B</mi> <mi>L</mi> </msubsup> <mrow> <mo>(</mo> <msup> <mover> <mi>y</mi> <mo>&OverBar;</mo> </mover> <mi>L</mi> </msup> <mo>)</mo> </mrow> <mo>]</mo> </mrow> </mfrac> </mrow> </math>

wherein, B is the fuzzy set corresponding to the variation of the rotating speed error, y is the solution fuzzy value, L is the fuzzy subset number, M is the total number of the fuzzy subset indexes, mu is the membership function,the average value is output for the maximum degree of membership,is a membership function on a fuzzy subset L in a fuzzy set B;

b5: the control quantity finally applied to the micro-nano satellite flight attitude control device is as follows:

K_p1＝K_p2+ΔK_p3，K_i1＝K_i2+ΔK_i3，

wherein, K_p1、K_p2、K_i1、K_i2Proportional and integral factors, respectively, Δ K_p3、ΔK_i3Respectively, a scale factor variation and an integral factor variation.