Method of control over spacecraft solar battery with protection against short-term faults of data on solar battery angular battery

FIELD: transport.

SUBSTANCE: invention relates to spacecraft electric power supply with the help of solar batteries. Proposed method consists in definition of preset angle of solar battery, measurement of its current angle and computation of design angle by angular velocity and spinning time. Solar battery acceleration angle (α_AC) and deceleration angle (α_DEC) are defined. Solar battery is spinned to threshold of drop-away (α_DROP ≈ (α_DEC) when mismatch between said preset and design angles is terminated. Before start of the control, preset angle is memorised to take initial preset angle as valid actual current angle. Mismatch threshold (α_THR) of said angles proceeding from angles α_AC and α_DEC, as well as minimum tolerable currents of solar battery. Angle transducer circle is divided into equal discrete sectors by magnitude a given the condition α_AC + α_DEC < σ < α_THR. Discrete sector bisectors are taken to be measured magnitudes. Period of valid current angle definition is set to the order and exceeding maximum duration of transducer data fault and smaller than minimum interval of faults train. Said interval is divided to four equal interval while analysis of measured and memorised magnitudes in said intervals are reset to generate validity signal. In the latter case, solar battery is spinned to mismatch between design and preset angles α_DROP to set new preset angle magnitude.

EFFECT: higher survivability and efficiency.

4 dwg

Proposed method of control the orientation of the solar batteries (SB) of the SPACECRAFT (SC) protected against short-term failures of information about the angular position of the solar battery relates to power supply systems AC and can be applied when managing the orientation of the solar panels of satellites, space stations and other types of SPACECRAFT.

Most modern SPACECRAFT can operate in Earth orbit for several years. For the operation of airborne equipment SPACECRAFT during all periods of operation are required to provide electricity, which typically is produced by using solar panels, installed elements that convert radiation from the Sun into electrical current. The magnitude of the current generated SAT, depends on the orientation of the plane of the working surface SB relative to the Sun. For automatic orientation SB use SPACECRAFT control systems, which include on-Board computers, which, in turn, implements the control algorithms on-Board equipment of the SPACECRAFT, including the management orientation SAT. The SPACECRAFT control system manages the device turn SAT, composed of electronic components and Electromechanical actuator is rigidly mounted on its output shaft panel SAT and angle sensor. elektronnye blocks device turn SAT admit, conversion commands generated from SPACECRAFT control systems, required to control Electromechanical actuator SA form, and the conversion information from the angle sensor in the form required for transmission to the control system of the SPACECRAFT.

Using algorithms, the movement management system implemented in the control system of the SPACECRAFT, based on the information received from the respective sensors (for example, astrogation or solar sensors), determine the direction to the Sun and form a specified angle SAT.

The control algorithms orientation Coll accept information about a given angular position of the SB, as well as information about the current angular position SAT with a fixed panel SAT.

Typically, the panel SB is mounted on the output shaft of the Electromechanical drive SB so that the angle sensor formed a zero value at the position normal to the working surface SB coincides with one of associated with the SPACECRAFT coordinate axes, for example with the yaw axis, and the axis of rotation of the SB - parallel to another, for example the axis of pitch.

Upon reaching the angle of misalignment between the given angle and angular position SB is equal to the threshold control algorithms SB initiate issuing commands to the rotation of the SB to reduce the angle error, which is transmitted from the on-Board automatic systemibuprofen in the device turn Coll. Upon reaching the angle between the equal to the angle you release the control algorithms SB initiate a command for stopping the rotation of the SAT. The measurement of the angular position of the SAT, as a rule, is accurate to a discrete sector of the angle sensor. The response time of the control algorithms orientation SAT, usually a multiple of the machine cycle on-Board computer control systems of SPACECRAFT and is several tens of milliseconds, for example 100 MS [1].

It is known that the accumulation of electrostatic charges on the outer surface of onboard equipment SPACECRAFT, including cable network, during its functioning periodically can cause short electrostatic discharges with a duration of tens of nanoseconds to several microseconds. Electrostatic discharges lead to the emission of electromagnetic energy and, thus, is accompanied by the generation of electromagnetic interference affecting the operation of on-Board equipment of the SPACECRAFT. In particular, this can lead to intermittent failures of information from the angle sensor device of turn SB.

The maximum frequency of the electrostatic discharge does not exceed 2 Hz [2] and corresponds to a period of more than 500 MS, which, in turn, exceeds the relevant period of 100 MS functioning SPACECRAFT control systems.

The most effective is m technical solution adopted for the prototype, is the method of controlling the orientation of the security Council, namely, that define the angle specified security Council as the position of the projection unit direction vector to the Sun in the plane of rotation normal to its working surface relative to the associated SPACECRAFT coordinate axes, measure the current angle of the SAT as the angular position of the normal to the working surface SAT in the plane of its rotation with accuracy up to a discrete sector angle sensor, calculates the estimated angle as the product of the angular velocity SS during its rotation, define the corners of his run-up and braking, set the threshold release below which stops the error between the desired and calculated angles SAT, as:

α_OTP≈α_TORM,

where α_OTP- threshold release,

rotate the solar panel in the direction of reducing the mismatch between the calculated and specified angles and stop its rotation when the threshold is reached release [3].

The disadvantage of this method is that in case of failure information from the angle sensor SA, can be calculated correction angle according to the received erroneous value and, accordingly, the incorrect orientation SAT on the direction of the Sun. The result is a reduction current produced by the SAT, which ultimately reduces the survivability of KA and n is the execution of assigned tasks.

The technical objective of the proposed method is an extension of functional capabilities, improving the survivability and effectiveness of the management system orientation SAT at short-term failures of information about the angular position SB coming from the angle sensor.

This technical result is achieved by the fact that in the known method of controlling the orientation of the solar panels of the spacecraft, namely, that define a given angle of the solar battery as the position of the projection unit direction vector to the Sun in the plane of rotation normal to its working surface is relatively related to the spacecraft coordinate axes, measure the current angle of the solar battery as the angular position of the normal to the working surface of the solar battery in the plane of its rotation with accuracy up to a discrete sector angle sensor, calculates the estimated angle as the product of the angular velocity of the solar battery during its rotation, define the corners of his run-up and braking, set the threshold release less that stopped the error between the desired and calculated angles of the solar battery as:

α_OTP≈α_TORM,

where α_OTP- threshold release,

rotate the solar panel in the direction of reducing the mismatch between the calculated and specified angles and stop the enemy who begins when the threshold is reached, release, optionally set the angular velocity of the rotation of the solar panels in excess of and more than the angular velocity of the rotation of the spacecraft around the Earth, before management memorize a given angle and take the initial value of the estimated angle for reliable value of the current angle, set the threshold of the error specified and stored angles, such as:

$$\left({\alpha }_{P\mathrm{And}CG}+{\alpha }_{T\mathrm{About}PM}\right)<{\alpha }_{PP}<\arccos \frac{I_{MIN}}{I_{MAX}}$$,

where α_ACCEL- the angle of the acceleration of the solar battery;

α_TORM- corner braking solar panels;

α_CRthe threshold of the error specified and stored angles;

I_MIN- the minimum current produced by the solar

battery;

I_MAX- maximum current produced by the solar battery,

break the circle angle sensor on an equal discrete sector value:

(α_ACCEL+α_TORM)<σ<α_CR,

where σ is the angular value of one discrete sector angle sensor, accept the provisions of the bis is actris these discrete sectors corresponding measured by the angle sensor values, specify the period for determining a reliable value of the current angle and maximum duration of the failure information from the angle sensor, and less than the minimum interval following failure of specified information, determine a reliable value of the current angle, the break each of these periods into four equal intervals of time, at the end of the first, second and third intervals memorize, respectively, first, second and third measured value of the current angle, and at the end of the fourth interval is considered reliable value of the current angle of the first stored value when matching it with the second or third memorized values or the second stored value equal with the third, and form the signal reliability, dropping a signal of trustworthiness, if the above matches none or two of the three stored values do not correspond to angular positions of the bisectors of discrete sectors of the angle sensor, if the specified angle is different from the memorized preset angle on the end of the previous rotation of the value more than the threshold mismatch between these angles, then assign the calculated angle is reliable current angle if the difference between the calculated current and accurate angles greater than the magnitude of the discrete sector angle sensor and strmilov the n signal reliability, this rotates the solar panel, if the mismatch between the calculated and specified angles greater than the threshold, release, and at the moment the threshold is reached, release memorize the new value of the specified angle.

Figure 1 shows the flight of the SPACECRAFT with SAT along the orbit, figure 2 presents the provisions of the projection direction of the Sun on the plane formed by the circle of rotation normal to the working surface of the SAT, as well as provisions specified normals measured by the angle sensor accurate to a discrete sector, figure 3 presents the sequence diagram for the formation of reliable values of the angle sensor, figure 4 - sequence diagram of the change of the set α_ASSreliable α_SHORTCUTSand the estimated α_CALCvalues of the angles SAT.

The proposed method of controlling the orientation of the solar panels of satellites with protection against short-term disruptions of information about the angular position SB is implemented as follows.

In the system design process management orientation Coll choose the device turn SAT with an Electromechanical drive with the angular velocity of rotation of the output shaft with a fixed SAT on order and more angular speed of rotation of the SPACECRAFT around the Earth, that is:

where ω_SAT- constant angular velocity of rotation of the SAT;

ω_CA- angular velocity of rotation of the SPACECRAFT around the Earth.

On your passport, as well as the results of experiments on the ground stands detect the angle of acceleration SA as the angular deviation of the normal to the working surface SB relatively associated with the SPACECRAFT coordinate axes since the beginning of the rotation SAT until it reaches a constant angular velocity, angle and braking SAT as the magnitude of the angular deviation of the specified normal upon cessation of the error specified and estimated angles until the end of the rotation. In addition, determine the minimum current necessary to ensure the health of the onboard equipment of the SPACECRAFT, which must form the SAT, as well as the maximum current that can generate SAT.

As is known, the current generated SAT, depends on the magnitude of the deflection angle of the normal to the working surface SS from the direction to the Sun and can be defined as:

$$I=I_{MAX}\cdot \cos {\alpha }_P\left(2\right)$$

g is e α _P- the angle of misalignment between the direction of the Sun and the normal to the working surface SB;

I is the current produced by the SAT;

I_MAX- the maximum possible current that can generate SAT.

In the design process define the maximum allowed deviation of the normal to the working surface SS from the direction to the Sun during the flight SPACECRAFT on a given orbit, at which SAT produces above the minimum allowable current at this set the threshold of the error specified and stored angles in the range:

$$\left({\alpha }_{P\mathrm{And}CG}+{\alpha }_{T\mathrm{About}PM}\right)<{\alpha }_{PP}<\arccos \frac{I_{MIN}}{I_{MAX}},\left(3\right)$$

where α_ACCEL- corner acceleration SA;

α_TORM- corner braking SAT;

α_CRthe threshold of the error specified and stored angles;

I_MIN- the minimum current, which produces the SAT to ensure the functioning of onboard equipment KA;

I_MAX- the maximum possible current that can the t to develop a SAT when flying SPACECRAFT in a given orbit.

The angle sensor located on the output shaft of the Electromechanical drive device to rotate the SAT, is a circle of 360°, divided into equal discrete sector, that is:

$$\sigma =\frac{{360}^o}{n},\left(4\right)$$

where σ is the angular size of the discrete sector angle sensor;

n is the number of discrete angular sectors.

The magnitude of the discrete sector angle sensor is set in the range:

$$\left({\alpha }_{P\mathrm{And}CG}+{\alpha }_{T\mathrm{About}PM}\right)<\sigma <{\alpha }_{PP}.\left(5\right)$$

Typically, the threshold of the error specified and stored angles chosen in the range of 5°-15°, and the angles of the acceleration and deceleration does not exceed the value of 1°.

The angle sensor SA is fixed to the output shaft of the Electromechanical drive device of turn SB in such a way that a corner is formed them corresponds to a position normal to the working surface SB relatively associated with the SPACECRAFT coordinate axes. At the time of turn SB angle sensor forms an angle value, corresponding to the position of the bisector is a discrete sector, within which is this normal.

During the flight the SPACECRAFT define the angle specified as the position of the projection unit direction vector to the Sun in the plane of rotation normal to its working surface relative to the associated SPACECRAFT coordinate axes.

Calculate the estimated angle as the product of the angular velocity SS during its rotation.

During the development phase, set the threshold release below which stops the error between the desired and the estimated angular position normal to the working surface SB, as:

α_OTP≈α_TORM.

Take the initial value of the estimated angle for reliable value of the current angle. The determination of reliable values of the angle sensor during operation of the control system orientation SB carried out within four equal time intervals, which split the period for determining a reliable value of the current angle, that is:

$$T_D=4\cdot T_{\mathrm{And}},\left(6\right)$$

where T_D- period for determining a reliable value of the current angle;

T_And- the time interval equal to a quarter of the period the determination is of significant value of the current angle.

As a rule, the period determining the accurate value of the current angle select multiple machine cycle on-Board computer control system of the SPACECRAFT. Reliable value of angle is formed when two of the three measured values of the angle sensor in the same period coincide, the period of determination of reliable values of the current angle is in the range:

$$10\cdot t_{MAX}<T_D<T_{MIN},\left(7\right)$$

where τ_MAX- the maximum duration of bad information coming from the angle sensor;

T_MIN- minimum interval following failure information from the angle sensor.

To determine a reliable value of the current angle at the end of the first, second and third time intervals memorize respectively first, second and third measured value of the current angle, and at the end of the fourth interval assign a reliable value of the current angle of the first stored value, if it coincides with the second or third, or second, if it coincides with the third stored value, in this form the signal reliability. In the event that these coincidences or no measured value does not correspond to the angular position of the bisector of one of the discrete sectors of the angle sensor, reset signal reliability, that is, at each period:

$$\begin{array}{l}e\mathrm{with\; a}l\mathrm{and}{\alpha }_{\mathrm{And}Ci\left(1\right)}={\alpha }_{\mathrm{And}Ci\left(2\right)},t\mathrm{about}{\alpha }_{D\mathrm{About}\mathrm{With\; a}Ti}={\alpha }_{\mathrm{And}Ci\left(1\right)},U_{Di}=\mathrm{1,}\\ e\mathrm{with\; a}l\mathrm{and}{\alpha }_{\mathrm{And}Ci\left(2\right)}={\alpha }_{\mathrm{And}Ci\left(3\right)},t\mathrm{about}{\alpha }_{D\mathrm{About}\mathrm{With\; a}T}={\alpha }_{\mathrm{And}C\left(2\right)},U_{Di}=\mathrm{1,}\\ e\mathrm{with\; a}l\mathrm{and}{\alpha }_{\mathrm{And}Ci\left(1\right)}\ne {\alpha }_{\mathrm{And}Ci\left(2\right)},\mathrm{and}{\alpha }_{\mathrm{And}Ci\left(2\right)}\ne {\alpha }_{\mathrm{And}Ci\left(3\right)},\mathrm{and}{\alpha }_{\mathrm{And}Ci\left(1\right)}\ne {\alpha }_{\mathrm{And}Ci\left(3\right)}\mathrm{,,}{U}_{Di}=\mathrm{0,}\left(8\right)\end{array}$$

where α_Is(1)α_Is(2)α_Is(3)the current measured and stored values of the angle sensor at the end of the first, second and third intervals determine the validity of the i-th cycle of rotation;

α_Cost- reliable value of the angle sensor at the i-th cycle of rotation;

U_Subjectsignal reliability on the i-th cycle of rotation;

i - the number of the cycle of rotation, i≥0.

In the presence of intermittent interference caused by, for example, electrostatic discharge, is formed bad information from the angle sensor via e-blocks SAT in the control system of the SPACECRAFT. DL is the duration of the failure angle sensor corresponds to the duration of the interference.

For example, the system has an angular speed of rotation of SB ω_SAT=0.6 degrees/s, the magnitude of the discrete sector angle sensor SA is σ=6°, the maximum duration of the failure information of the angle sensor SA, caused by electrostatic discharge, is τ_MAXor =1.5 μs, the minimum distance between failures T_MIN=1, which corresponds to a frequency of 1 Hz.

For this option, if the cycle calculations SPACECRAFT control systems is a multiple of the machine cycle control system AC 100 MS and corresponds to the measurement interval T_And=200 MS [1], condition (6), (7) run as:

10·τ_MAX=10·1,5 µs=0,000015;

T_D=4·T_And=4-200 MS=0.8 s;

T_MIN=1 c.

Before management memorize a given angle and set the calculated corner of the initial value, that is:

$${\alpha }_{C\mathrm{And}D\left(i-1\right)}={\alpha }_{C\mathrm{And}Di},{\alpha }_{P\mathrm{And}\mathrm{With\; a}Hi}={\alpha }_0,\left(9\right)$$

where α_Sad- the current value of the specified angle at the beginning of the 1st day of rotation;

α_ASS(i-1)- memorized value is set to the second corner at the end of the (i-1)-th rotation;

α₀- the initial value of the estimated angle;

α_CALC(i)- the calculated angle at the i-th cycle of rotation.

Permit rotation of the SAT, if the current angle is different from the memorized at the end of the previous rotation of a given angle by the amount over the threshold of the error specified and stored angles, i.e. when:

$$\left|{\alpha }_{C\mathrm{And}Di}-{\alpha }_{C\mathrm{And}D\left(i-1\right)}\right|>{\alpha }_{PP},\left(10\right)$$

thus, before beginning the rotation assign the calculated angle value current reliable angle if the difference between them exceeds a discrete sector of the angle sensor at the time of permit rotation of the generated signal reliability, that is:

$$\begin{array}{c}{\alpha }_{P\mathrm{And}\mathrm{With\; a}Hi}={\alpha }_{D\mathrm{About}\mathrm{With\; a}Ti}\\ e\mathrm{with\; a}l\mathrm{and}\left|{\alpha }_{C\mathrm{And}Di}-{\mathrm{the}}_{C\mathrm{And}D\left(i-1\right)}\right|>{\alpha }_{PP}\mathrm{and}\left|{\alpha }_{P\mathrm{And}\mathrm{With\; a}Hi}-{\alpha }_{D\mathrm{About}\mathrm{With\; a}Ti}\right|>\sigma \mathrm{and}{U}_{Di}=1.\left(11\right)\end{array}$$

It should be noted that in the process of managing the mismatch between the calculated and the actual angular position, SAT gradually increases as the real angular velocity SS is influenced by various factors: the backlash in the mechanism of the Electromechanical drive, change the friction of the moving parts in zero gravity, vacuum, and under the influence of cosmic and solar radiation, temperature effects, fluctuations in the panel SAT in the moments of the beginning and end of the rotation, change of inertial forces on the turns KA and others. Because of these factors there has been a gradual divergence between the actual angular position of the SB from the settlement.

Begin rotation of the SAT, if the current angle and memorized a given the second angle is different on the amount over the threshold mismatch between the said angles, and if the mismatch between the calculated and specified angles greater than the threshold of release, i.e. when:

$$\left|{\alpha }_{P\mathrm{And}\mathrm{With\; a}Hi}-{\alpha }_{D\mathrm{About}\mathrm{With\; a}Ti}\right|>{\alpha }_{\mathrm{About}TP}.\left(12\right)$$

During rotation SAT calculate the estimated angle as:

$${\alpha }_{P\mathrm{And}\mathrm{With\; a}H}={\alpha }_{P\mathrm{And}\mathrm{With\; a}Hi}+{\omega }_{\mathrm{With\; a}B}\cdot t_{\mathrm{With\; a}Bi},\left(13\right)$$

where α_Rasch- the estimated value of the angular position of the SB at the beginning of the rotation;

t_SBthe time of rotation of the SAT. Stop the rotation of the SAT when the threshold is reached release:

$$\left|{\alpha }_{P\mathrm{And}\mathrm{With\; a}Hi}-{\alpha }_{C\mathrm{And}Di}\right|\le {\alpha }_{\mathrm{About}TP}(14)$$

however remember the current value of the specified angle:

$${\alpha }_{C\mathrm{And}DCi}={\alpha }_{C\mathrm{And}Di}.\left(15\right)$$

Figure 1 shows the flight of the SPACECRAFT with SAT along the orbit, where:

1 - Ground;

2 - orbit SATELLITES;

3 - the direction of radiation from the Sun;

4 - case KA;

5 - panel SAT;

6 - angle sensor SA;

N - set the direction of orientation of the SAT as a projection of the unit direction vector to the Sun in the plane of rotation normal to the working surface SB;

N_SATis normal to the working surface SB;

X, Y, Z - axis associated with the SPACECRAFT coordinate system, with the Z axis perpendicular to the plane of drawing up;

X_SAT, Y_SAT, Z_SAT- axis associated with SB coordinate system, Z_SATcoincides with the Z-axis and also directed perpendicular to the plane of drawing up;

Δα is the angular misalignment between the direction of the Sun and the normal to the working surface SB;

ω_O- angular velocity of rotation of the SPACECRAFT around the Earth;

ω_SAT- angular velocity of rotation SAT around the axis Z_SAT.

In figure 1 around the Earth 1 to orbit 2 with angular velocity ω Ospinning SPACECRAFT. In the direction of radiation of the Sun relative to the housing 3 KA 4 is the orientation of the panel SB 5. The angular position of the projection normal to the working surface SB N_SATregarding the unit direction vector to the Sun N is measured by the angle sensor 6. With the housing 4 KA rigidly connected to the axis X, Y, Z coordinate system. In turn, X_SAT, Y_SAT, Z_SATform associated with SB coordinate system. SAT rotates around the axis of Z_SATdirected perpendicularly upward to the plane of the drawing, and the direction of the axes Z_SATand Z are the same, and the plane formed by axes X_SATand Y_SAT,parallel to the plane formed by the axes X and Y. the Direction normal to the working surface SB N_SATcoincides with the direction of the axis X_SAT.

The angle sensor SA 6 generates a zero value when the coincidence of the directions of the axes X_SATand X. In accordance with the direction of radiation from the Sun 3 determine the projection direction of the unit direction vector to the Sun N on the plane formed by the axes X_SATand Y_SAT.

During the flight SPACECRAFT in orbit 2 with angular velocity ω_Othe panel SAT 5 deploying thus, to ensure the minimum angle between Δα between the projection direction of the unit direction vector to the Sun N the plane of rotation of the regulations is whether the working surface SB, formed by the axes X_SATand Y_SATand the specified normal N_SAT, resulting in the formation of the maximum possible current.

When managing a considered way, if the angle mismatch between the current selected angle, i.e. the position of the projection of N, and memorized the given angle at the end of the previous rotation of the SAT more than the threshold of the error specified and stored corners, as well as the mismatch between the calculated angle, i.e. the position of the normals N_SATand given angle, i.e. the projection of N, over the threshold of release, the panel SAT 5 deploy with angular velocity ω_SATto align the provisions of the normals N_SATthe position of the projection n

Figure 2 presents the circle of rotation normal to the working surface SB, the position of which is measured by the angle sensor, where:

7 - circle of rotation normal to the working surface SB;

8 - the center of the circle of rotation normal to the working surface SB;

N - set the direction of orientation of the SAT as a projection of the unit direction vector to the Sun in the plane of rotation normal to the working surface SB;

N_SATis normal to the working surface SB;

α_σ0α_σ1α_σ2,...,α_σjα_(j+1)... α_σ(n-2)α_σ(n-1)discrete sector angle sensor;

N_j- discrete bisector of the sector α_σj

α_{P is} the threshold of the error specified and stored angles;

σ - angular value of a discrete sector of the angle sensor.

α_RACESthe angle mismatch between the current predetermined direction and a position normal to the working surface SB;

α_OTP- the threshold of release.

In figure 2 the angle sensor SS is made in the form of a circle of rotation normal to the working surface SAT 7 centre 8. The circle of 360° is divided into n equal discrete sectors α_σ0α_σ1α_σ2,...,α_σjα_(j+1)... α_σ(n-2)α_σ(n-1). The specified sensor is mounted on the body of the SPACECRAFT so that the zero position coincided with the X-axis associated with the SPACECRAFT coordinate system. Thus, the measurement of the angular position normal to the working surface SB N_SATis accurate to a discrete sector size σ and the angle sensor generates values corresponding to the provisions of the bisectors of each of the sectors α_σ0,...α_σ(n-1).

When management consider the way the panel SAT starts rotation when the misalignment angles between the current N and stored at the end of the previous rotation given direction to the Sun N_ZAPover the threshold of the error specified and stored angles α_CRand if the position of the normal to the working surface SB N_SATdifferent from the currently set direction the value of N at an angle α _Pmore threshold release α_OTP.

Figure 3 presents the sequence diagram for the formation of reliable values of the angle sensor, where:

U_Psignals interference;

τ_P1τ_P2that is, τ_P3τ_A4- duration interference that cause undesired angle sensor;

τ₁τ₂τ₃τ₄- duration failures angle sensor;

T₁T₂T₃- intervals of repetition failures angle sensor;

α_ISM- the measured angle SAT;

U_T- beats memorizing the measured values of the angles by the angle sensor SA;

T_D- period for determining accurate values of the measured angle;

α_SAP- measured and stored values of the angle sensor at the end of the first interval of definition of reliability;

α_SAP- measured and stored values of the angle sensor at the end of the second interval of definition of reliability;

α_SAP- measured and stored values of the angle sensor at the end of the third interval of definition of reliability;

U_Dsignal reliability of the measured values of the angle sensor;

α_SHORTCUTSvalues reliable corner SAT;

α₁α_S2is measured by the angle sensor of angular values corresponding to the actual angular positions of the SB;

α_C1α_C2α_C3α_C4is measured by the angle sensor of upowaznienie, the corresponding distorted angular provisions of SB;

9, 13, 17, 21, 25 - moments to remember the values of the angle sensor at the end of the first interval of definition of reliability;

α₉α₁₃α₁₇α₂₁α₂₅- stored values of the angle sensor at the end of the first interval of definition of reliability;

10, 14, 18, 22, 26 - moments to remember the values of the angle sensor at the end of the second interval of definition of reliability;

α₁₀α₁₄α₁₈α₂₂α₂₆- stored values of the angle sensor at the end of the second interval of definition of reliability;

11. 15, 19, 23, 27 - moments to remember the values of the angle sensor at the end of the third interval of definition of reliability;

α₁₁α₁₅α₁₉α₂₃α₂₇- stored values of the angle sensor at the end of the third interval of definition of reliability;

12. 16, 20, 24, 28 - moments determine the reliability at the end of the fourth interval of definition of reliability;

α_Dα_16Dα_Dα_24Dα_D- memorized reliable values of the angle sensor at the end of the fourth interval of definition of reliability.

Figure 3. providing accurate sensor values of the angle α_SHORTCUTSis quanta U_Twith a period equal to T_Dwhile each period sub> Ddivided into 4 equal parts.

In moments 9, 13, 17, 21, 25 is remembering the first α_SAPin moments 10, 14, 18, 22, 26 second α_SAPand in moments 11, 15, 19, 23, 27 third α_SAPangular positions SB measured by the angle sensor.

In moments 12, 16, 20, 24, 28 compares the first, second and third measured values of the angle sensor and generate an accurate angle α_SHORTCUTS.

Angular values α₁α_S2correspond to the actual angular positions of the Council.

At intervals of T₁, T₂T₃there are some faults angle sensor duration τ₁τ₂τ₃τ₄caused by interference, respectively, of duration τ_P1τ_P2τ_P3τ_A4different amplitude U_Pand:

-τ_P1<<τ₁<T_Dτ_P2<<τ₂<T_Dτ_P3<<τ₃<T_Dτ_A4<<τ₄<T_D;

in moments 9, 13, 18 and 23, respectively remembered the failed values α_C1α_C2α_C3α_C4generated by the angle sensor;

At the moment 12 is formed of reliable sensor value of the angle α_D=α₁since α₁₀=α₁₁=α₁U_D=1, when this failed, the value of α₉=α_C1ignored.

At the moment 16 is formed of reliable sensor value of the angle α_16D=α_{È1, since α10=α11=α1UD=1, when this failed, the value of α13=αC2ignored.}

At the moment 20 is formed of reliable sensor value of the angle α₀=α_È1,since α₁₇=α₁₉=α₁U_D=1, when this failed, the value of α₁₈=α_C3ignored.

At the moment 24 a reliable value of the angle sensor is retained from the previous cycle α_24D=α₁since α₂₁=α₁α₂₂=α_S2α₂₃=α_C4then there is α₂₁≠022, α₂₁≠α₂₃α₂₂≠α₂₃while U_D=0.

At the moment 28 is formed reliable sensor value of the angle α_D=α_S2since α₂₆=α₂₅=α_S2U_D=1.

Figure 4 presents a graph of position control of the SA of the proposed method with correction of the calculated angle and the corresponding graph of the signal reliability of the measured values of the angle sensor, where:

U_Dsignal reliability of the measured values of the angle sensor;

α_ASS- set angle SAT;

α_SHORTCUTS- valid measured angle SAT;

α_CALC- the calculated angle SAT;

α_SADα_SAD- set angles at the time of completion of rotation of the SAT;

α_SADα_SAD- set angles at the start of rotation of the SAT;

α_COSTα_COST- accurate measurement is by the angles at the time of completion of rotation of the SAT;

α_RASCHα_RASCH- the calculated angles at the time of completion of rotation of the SAT;

σ - angular value of one discrete sector angle sensor;

29, 33 moments of the termination of the rotation SB;

30, 34 - moments start the rotation of the SAT;

31 - moments termination signal reliability;

32 - point resume signal reliability;

α_CRthe threshold of the error specified and stored angles;

α_OTP- the angle of release;

Δ₁, Δ₂- angles to the mismatch between the estimated and true values of the angles.

In the figure 4 the sequence diagram shows the change of the set α_ASSreliable measured α_SHORTCUTSand the estimated α_CALCvalues of the angles SAT.

At the moment 29 achievements of the error between the calculated α_CALC=α_RASCHand given α_ASS=α_SADangles less than the threshold release α_OTP, that is, conditions (14), the rotation of the SAT is terminated.

At the moment 30 a mismatch between the specified angle α_ASS=α_SADand remembered the given angle α_SAD=α_SADexceeds the threshold error set and memorized angles α_CR, that is, the condition (10), and the mismatch between the calculated α_CALC=α_RASCHand given α_ASS=α_SADangles boleadora release α _OTP, that is, the condition (12). In addition, at the moment 30 a generated signal reliability U_D=1 and the error term Δ₁between the calculated α_CALC=α_RASCHreliable and α_SHORTCUTS=α_COSTangles more discrete sector angle sensor σ, that is, the condition (11). Given the generated conditions at time 30, corrects the estimated angle, the corrected estimated angle formed significant value, i.e. α_CALC=α_COST. Further rotating security Council, during which the computation of the estimated angle by the equation (13).

At the moment 33 achievements of the error between the calculated α_CALC=α_RASCHand given α_SAD=α_SADangles less than the threshold release α_OTP, that is, conditions (14), the calculation of the angle and rotation of the SS stops. The lack of reliable values of the measured angle from point 31 to point 32 will not affect the value of the calculated angle.

At the moment 34 the mismatch between the current selected angle α_ASS=α_SADand remembered the given angle α_SEDS=α_SADexceeds the threshold error set and memorized angles α_OTP, that is, the condition (10), and the mismatch between the calculated α_CALC=α RASCHand given α_ASS=α_SADangles significantly more threshold release α_OTP, that is, the condition (12). In addition, at the time 33 formed signal reliability U_D=1 and the error term Δ₁between the calculated α_CALC=α_RASCHreliable and α_SHORTCUTS=α_COSTangles less discrete sector angle sensor σ, that is, condition (11) is not executed. Given the generated conditions at the time 33, the correction of the calculated angle is not possible. Further rotating security Council, during which the computation of the estimated angle by the equation (13).

The proposed method allows proper orientation SAT at short-term failure information from the angle sensor, caused by, for example, static discharges, due to the comparative analysis of information about the angular position SB, obtained at different points in time, and by reducing the influence of faulting values generated by the angle sensor SAT on the Bank angle due to the increase in the interval of the calculated correction angle SAT at actual value, and, thus, to provide the amount of current sufficient for the operation of airborne equipment that increases the survivability of the SPACECRAFT as a whole.

Sources of information

1. The onboard systems of the spacecraft control. the od editor doctor of technical Sciences, Professor Assyria. M., Izd-vo MAI-PRINT, 2010, s.219, 243.

2. Electrostatic discharges on the surface of the spacecraft and their impact on the onboard cable network. Anthropoi. The dissertation on competition of a scientific degree of candidate of technical Sciences. M., 2007, s. www.dslib.net/kondensat/jelektrostaticheskie-razrjady-na-poverhnosti-kosmicheskih-apparatov-i-ih-vozdejstvie.html.

3. RF patent 2356788, VS 1/00, 28.12.2007,

The method of controlling the orientation of the solar panels of the spacecraft with protection from short-term failures of information about the angular position of the solar battery, which determine the angle of the solar battery as the position of the projection unit direction vector to the Sun in the plane of rotation normal to its working surface is relatively related to the spacecraft coordinate axes, measure the current angle of the solar battery as the angular position of the normal to the working surface of the solar battery in the plane of its rotation with accuracy up to a discrete sector angle sensor, calculates the estimated angle as the product of the angular velocity of the solar battery during its rotation, define the corners of his run-up and braking, ask threshold release below which stops the error between the desired and calculated angles of the solar battery:
α_OTP≈ α_TORM,
where α_OTP- threshold release,
frawaydanny the battery in the direction of reducing the mismatch between the calculated and specified angles and stop its rotation when the threshold is reached, release, wherein the set angular speed of rotation of the solar panels in excess of and more than the angular velocity of the rotation of the spacecraft around the Earth, before management memorize a given angle and take the initial value of the estimated angle for reliable value of the current angle, set the threshold of the error specified and stored angles as:
$$\left({\alpha }_{P\mathrm{And}CG}+{\alpha }_{T\mathrm{About}PM}\right)<{\alpha }_{PP}<\arccos \frac{I_{MIN}}{I_{MAX}}$$,
where α_ACCEL- the angle of the acceleration of the solar battery;
α_TORM- corner braking solar panels;
α_CRthe threshold of the error specified and stored angles;
I_MIN- the minimum current produced by the solar battery;
I_MAX- maximum current produced by the solar battery,
break the circle angle sensor on an equal discrete sector value:
(α_ACCEL+ α_TORM)< σ < α_CR,
where σ is the angular value of one discrete sector angle sensor, accept the terms of the bisectors of the criminal code of the related discrete sectors corresponding measured by the angle sensor values, specify the period for determining a reliable value of the current angle and maximum duration of the failure information from the angle sensor, and less than the minimum interval following failure of specified information, determine a reliable value of the current angle, the break each of these periods into four equal intervals of time, at the end of the first, second and third intervals memorize, respectively, first, second and third measured value of the current angle, and at the end of the fourth interval is considered reliable value of the current angle of the first stored value when matching it with the second or third memorized values or the second stored value when a match is his third, and form the signal reliability, dropping a signal of trustworthiness, if the above matches none or two of the three stored values do not correspond to angular positions of the bisectors of discrete sectors of the angle sensor, if the specified angle is different from the memorized preset angle on the end of the previous rotation of the value more than the threshold mismatch between these angles, then assign the calculated angle is reliable current angle if the difference between the calculated current and accurate angles greater than the magnitude of the discrete sector angle sensor and form the Rowan signal reliability, this rotates the solar panel, if the mismatch between the calculated and specified angles greater than the threshold, release, and at the moment the threshold is reached, release memorize the new value of the specified angle.