Anti-interference control method and system for control moment gyro frame servo system

Abstract

The present invention provides an anti-interference control method and system for a control moment gyroscope frame servo system, belonging to the technical field of mechatronic system control. According to the working principle analysis of the control moment gyroscope, considering the multi-source interference suffered by the frame servo system during operation, a mathematical model of the frame servo system in the presence of multi-source interference is established; the multi-source interference suffered by the frame servo system under actual working conditions is classified, analyzed and modeled; a corresponding disturbance observer framework is designed for the disturbance classification result of the frame servo system to estimate the disturbance; according to the constructed non-cascaded control framework of the system, a finite-time current constraint controller is designed in combination with the disturbance estimation to simultaneously achieve current protection and suppression of mismatched interference; a composite anti-interference controller is constructed, and a suitable Lyapunov function is selected to prove the stability of the system, solving the influence of multi-source disturbances such as modelable interference and unmodelable interference on the servo accuracy of the control moment gyroscope frame servo system.

Description

Technical Field

[0001] The present invention relates to the technical field of electromechanical system control, and in particular to an anti-interference control method and system for a control moment gyro frame servo system. Background Art

[0002] As an inertial actuator, the control moment gyro (CMG) is widely used in the spacecraft attitude control system due to its large output torque, rapid response, high stability and low power consumption. CMG usually consists of two parts: a high-speed rotor system and a frame servo system. In actual engineering practice, in order to achieve high-precision output torque of CMG, it is necessary to ensure that the frame servo system has good servo performance. But in fact, due to the particularity of the system structure and the complexity of the working environment, the CMG frame servo system will inevitably be affected by multi-source interference. The existence of external interference and unmodeled dynamics seriously reduces the dynamic performance of the frame servo system, and the resulting state fluctuations are transmitted to the spacecraft, ultimately affecting the attitude control performance of the spacecraft. Therefore, for the CMG frame servo system, it is particularly important to accurately classify and analyze and accurately suppress the multi-source interference of the system to ensure its speed tracking performance and improve its anti-interference ability.

[0003] At present, the anti-interference research on CMG frame servo system focuses on only considering a single disturbance, and various anti-interference control theories and methods have their own characteristics and limitations. The anti-interference problem of CMG frame servo system under multi-source interference needs to be solved urgently. Summary of the invention

[0004] The object of the present invention is to provide a composite layered anti-interference control method and system based on multi-source disturbance of a control moment gyro frame servo system, so as to solve at least one technical problem existing in the above-mentioned background technology.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] In one aspect, the present invention provides an anti-interference control method for a control moment gyro frame servo system, comprising:

[0007] According to the working principle of the control moment gyro, considering the multi-source interference of the frame servo system during operation, the mathematical model of the frame servo system under the existence of multi-source interference is established.

[0008] Based on the mathematical model of the frame servo system, the multi-source disturbances to which the frame servo system is subjected in actual working conditions are classified, including rotor unbalance disturbances that can be modeled and lumped disturbances that cannot be modeled.

[0009] According to the classification results of multi-source interference, an adaptive fine interference observer is constructed to estimate the multi-source interference;

[0010] Combining the multi-source interference estimation results, a finite-time current constraint controller is constructed to achieve current protection and suppression of mismatched interference.

[0011] Based on the feedforward compensation of adaptive fine disturbance observer and the feedback control of finite time current constraint controller, a composite anti-disturbance controller is constructed to realize the anti-disturbance control of control moment gyro frame servo system.

[0012] Preferably, a mathematical model of a frame servo system under the presence of multi-source interference is established, including:

[0013]

[0014] Among them, i d and i q are the stator currents of the d-axis and q-axis respectively, u d and u q are the stator voltages of the d-axis and q-axis respectively, L d and L q are the stator inductances of the d-axis and q-axis, R s is the stator resistance, ω is the rotor angular velocity, n p is the pole pair number, ψ f is the magnetic flux, J is the moment of inertia, d represents the multi-source interference to the system, T d is the rotor unbalance disturbance, T f is the nonlinear friction torque, T g is the gyro torque and T c is the cogging torque, torque coefficient k t satisfy

[0015] Preferably, based on the mathematical model of the frame servo system, the multi-source disturbances to which the frame servo system is subjected in actual working conditions are classified, including rotor unbalance disturbances that can be modeled and lumped disturbances that cannot be modeled, including: according to whether the disturbance model information is known, the multi-source disturbances are divided into the following two categories:

[0016] d=d 1 +d 2 ;

[0017] Among them, d 1 is the rotor unbalance disturbance, which is a high-frequency harmonic disturbance that can be modeled; d 2 Lumped disturbances that are considered unmodelable include: nonlinear friction torque, gyroscopic torque, and cogging torque;

[0018] Analyze and model rotor unbalance disturbances:

[0019] When the rotor rotates, the static unbalanced mass generated by the deviation of its geometric center from the inertia center will generate a radial periodic centrifugal inertia force F on the shaft. s :

[0020]

[0021] Among them, U s =m s rm s , m s is the lumped static unbalanced mass, Ω is the speed of the high-speed rotor flywheel, is m s The initial phase angle of

[0022] When the rotor rotates, the dynamic unbalanced mass generated by the staggered main inertia axis and the rotation axis will produce an axial periodic inertia moment T on the frame axis. d :

[0023]

[0024] Among them, U d =m d r md h f , m d is the lumped dynamic unbalance mass, is m d The initial phase angle of

[0025] Unbalanced disturbance torque T d is a harmonic disturbance with known frequency but unknown amplitude and phase, which can be modeled as an exogenous system:

[0026]

[0027] Here, the state ξ is defined as

[0028] The speed equation of the system is combined with the disturbance model to obtain the following equation:

[0029]

[0030]

[0031] The observable matrix is Due to its full rank, T d Can be observed.

[0032] Preferably, according to the classification result of the multi-source interference, an adaptive fine interference observer is constructed to estimate the multi-source interference, including:

[0033] For the case where the frame servo system has only a single harmonic disturbance d, a disturbance observer is designed to estimate the disturbance. The design is as follows:

[0034]

[0035] in, are the estimates of d and ξ respectively, z is an auxiliary variable, and the vector is the disturbance observer gain to be designed;

[0036] For the frame servo system with modelable disturbance d 1 and unmodelable disturbance d 2 Design an adaptive fine disturbance observer to estimate the disturbance:

[0037] Define the sliding mode variable: s = ω-ζ, where ζ satisfies the following dynamics:

[0038]

[0039] in, They are d 1 , d 2 Estimator of , v = λ 1 sign(s) is the sliding mode term, scalar λ 0 and λ 1 is the dynamic gain to be designed;

[0040] Subtracting the system speed equation from the ζ dynamic equation, we can get the following equation:

[0041]

[0042] in, is the interference estimation error;

[0043] Then, the design of the adaptive fine disturbance observer is as follows:

[0044]

[0045] in, are the estimates of ξ and β respectively, η is an auxiliary variable, and the vector Scalar K 2 and K 3 is the gain of the adaptive fine disturbance observer to be designed;

[0046] Select the Lyapunov function: V 1 =s T s, when the gain λ 0 and λ 1 They are selected as: 0 ≥0, , it can be proved that: That is, the sliding mode variable s can converge to 0; due to Can be equivalent to λ 1 sign(s), that is:

[0047] On the basis that it has been proved that the sliding mode variable s can converge to 0, the Lyapunov function is selected: in:

[0048] When the gain K 2 and K 3 They are selected as: K 2 >0,K 3 >0, the adaptive law is:

[0049]

[0050] Among them, γ 0 is a normal number, It can converge to a bounded set in finite time.

[0051] Preferably, a finite time current constraint controller is constructed in combination with the multi-source interference estimation results, including:

[0052] Considering the ideal frame servo system model without multi-source interference, the speed tracking error e is defined as: 1 =ω r -ω, The error system model is established as follows:

[0053]

[0054] Among them, i q Satisfy the constraint condition |i q |<c;

[0055] Based on the error system model, a finite-time current constraint controller is designed as shown below:

[0056]

[0057] Among them, k 1 , k 2 and the penalty term l are adjustable positive parameters; 0<α 1 <1, β>α 2 .

[0058] Preferably, based on the feedforward compensation of the adaptive fine disturbance observer and the feedback control of the finite time current constraint controller, a composite anti-interference controller is constructed to realize the anti-interference control of the control moment gyro frame servo system, including:

[0059] For the non-cascade control framework of the frame servo system, a composite control law is designed based on feedback control based on finite-time current constraints and feedforward compensation based on adaptive fine disturbance observer:

[0060]

[0061] Where L is the inductance of the frame servo system.

[0062] In a second aspect, the present invention provides an anti-interference control system for a control moment gyro frame servo system, comprising:

[0063] The first building module is used to analyze the working principle of the control moment gyro, consider the multi-source interference suffered by the frame servo system during operation, and establish a mathematical model of the frame servo system under the existence of multi-source interference;

[0064] A classification module is used to classify the multi-source disturbances suffered by the frame servo system in actual working conditions based on the mathematical model of the frame servo system, including rotor unbalance disturbances that can be modeled and lumped disturbances that cannot be modeled;

[0065] An estimation module, used for constructing an adaptive fine interference observer to estimate the multi-source interference according to the classification result of the multi-source interference;

[0066] The second building module is used to combine the multi-source interference estimation results to build a finite time current constraint controller to achieve current protection and suppression of mismatch interference;

[0067] The control module is used to construct a composite anti-interference controller based on feedforward compensation of an adaptive fine disturbance observer and feedback control of a finite-time current constraint controller to achieve anti-interference control of a control moment gyro frame servo system.

[0068] In a third aspect, the present invention provides a non-transitory computer-readable storage medium, which is used to store computer instructions. When the computer instructions are executed by a processor, the anti-interference control method of the control torque gyro frame servo system as described above is implemented.

[0069] In a fourth aspect, the present invention provides a computer program product, comprising a computer program, wherein the computer program, when executed on one or more processors, is used to implement the anti-interference control method for the control moment gyro frame servo system as described above.

[0070] In a fifth aspect, the present invention provides an electronic device, comprising: a processor, a memory and a computer program; wherein the processor is connected to the memory, the computer program is stored in the memory, and when the electronic device is running, the processor executes the computer program stored in the memory so that the electronic device executes instructions for implementing the anti-interference control method of the control torque gyro frame servo system as described above.

[0071] The beneficial effects of the present invention are as follows: the influence of mismatched multi-source interference on the servo accuracy of the control moment gyro frame servo system is effectively attenuated and suppressed; the q-axis current effectively satisfies the given current constraint and realizes overcurrent protection; the control moment gyro frame servo system can have good servo performance, and the actual angular velocity can track the reference value with high precision.

[0072] Additional advantages of the present invention will be more clearly given in the following description or learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0074] Figure 1 The present invention is a flowchart of a composite layered anti-interference control method for multi-source disturbances of a control moment gyro frame servo system according to an embodiment of the present invention.

[0075] Figure 2 It is a schematic diagram of the generation of static unbalance interference of a high-speed rotor of a control torque gyroscope according to an embodiment of the present invention.

[0076] Figure 3 It is a schematic diagram of the generation of dynamic unbalance interference of a high-speed rotor of a control torque gyroscope according to an embodiment of the present invention.

[0077] Figure 4 It is a schematic diagram of a rotation speed tracking error curve in a composite layered anti-interference control method based on multi-source disturbance of a control moment gyro frame servo system according to an embodiment of the present invention.

[0078] Figure 5 It is a schematic diagram of a q-axis current curve in a composite layered anti-interference control method based on multi-source disturbance of a control moment gyro frame servo system according to an embodiment of the present invention.

[0079] Figure 6 It is a schematic diagram of an estimated error curve of multi-source disturbances suffered by the control moment gyro frame servo system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0080] To facilitate understanding of the present invention, the present invention is further explained below with reference to specific embodiments in conjunction with the accompanying drawings, and the specific embodiments do not constitute a limitation on the embodiments of the present invention.

[0081] Those skilled in the art should understand that the drawings are merely schematic diagrams of embodiments, and the components in the drawings are not necessarily necessary for implementing the present invention.

[0082] Example 1

[0083] In this embodiment 1, firstly, an anti-interference control system for a control moment gyro frame servo system is provided, comprising: a first construction module, for establishing a mathematical model of the frame servo system under the presence of multi-source interference based on the working principle of the control moment gyro, taking into account the multi-source interference suffered by the frame servo system during operation; a classification module, for classifying the multi-source interference suffered by the frame servo system in actual working conditions based on the mathematical model of the frame servo system, including modelable rotor unbalance disturbances and non-modelable lumped disturbances; an estimation module, for constructing an adaptive fine interference observer to estimate the multi-source interference based on the classification results of the multi-source interference; a second construction module, for constructing a finite-time current constraint controller in combination with the multi-source interference estimation results to achieve current protection and suppression of mismatched interference; a control module, for constructing a composite anti-interference controller based on the feedforward compensation of the adaptive fine interference observer and the feedback control of the finite-time current constraint controller to achieve anti-interference control of the control moment gyro frame servo system.

[0084] In this embodiment 1, the above-mentioned system is used to implement an anti-interference control method for a control moment gyro frame servo system, including: using a first building module, according to the working principle of the control moment gyro, considering the multi-source interference suffered by the frame servo system during operation, and establishing a mathematical model of the frame servo system under the existence of multi-source interference; using a classification module, based on the mathematical model of the frame servo system, classifying the multi-source interference suffered by the frame servo system in actual working conditions, including modelable rotor unbalance disturbances and unmodelable lumped disturbances; using an estimation module, based on the classification results of the multi-source interference, constructing an adaptive fine interference observer to estimate the multi-source interference; using a second building module, combining the multi-source interference estimation results, constructing a finite-time current constraint controller to achieve current protection and suppression of mismatch interference; finally, using a control module, based on the feedforward compensation of the adaptive fine interference observer and the feedback control of the finite-time current constraint controller, constructing a composite anti-interference controller to achieve anti-interference control of the control moment gyro frame servo system.

[0085] The frame servo system with multiple interference sources is modeled as follows:

[0086]

[0087] It has been assumed that: the saturation of the motor core is ignored, the eddy current and hysteresis loss in the motor are not considered, and the current in the motor is a symmetrical three-phase sine wave. d and i q are the stator currents of the d-axis and q-axis respectively, u d and u q are the stator voltages of the d-axis and q-axis respectively, L d and L q are the stator inductances of the d-axis and q-axis respectively. The stator inductance of the surface-mounted permanent magnet synchronous motor satisfies L d =L q =L, R s is the stator resistance, ω is the rotor angular velocity, n p is the pole pair number, ψ f is the magnetic flux, J is the moment of inertia, and d represents the multi-source interference to the system. Here we consider: T d is the rotor unbalance disturbance, T f is the nonlinear friction torque, T g is the gyro torque and T c is the cogging torque. In addition, the torque coefficient k t satisfy

[0088] Typically, vector control methods are applied to frame servo systems. Specifically, the stator current is decoupled into the excitation component i by spatial coordinate transformation. d and torque component i q , thus achieving independent flux and torque control. In order to eliminate the coupling effect between ω and dq axis current, the d axis reference current i d * Set to i d * = 0. If the controller of the d-axis current loop works in an ideal state, we can obtain i d =i d * = 0. Therefore, the mathematical model of the system can be approximately simplified to the following form:

[0089]

[0090] Where L is the inductance of the frame servo system.

[0091] Based on the mathematical model of the frame servo system, the multi-source disturbances suffered by the frame servo system in actual working conditions are classified, including modelable rotor unbalance disturbances and unmodelable lumped disturbances, including: According to whether the disturbance model information is known, the multi-source disturbances are divided into the following two categories:

[0092] d=d 1 +d 2 ;

[0093] Among them, d 1 is the rotor unbalance disturbance, which is a high-frequency harmonic disturbance that can be modeled; d 2 Lumped disturbances that are considered unmodelable include: nonlinear friction torque, gyroscopic torque, and cogging torque;

[0094] Analyze and model the rotor imbalance disturbance on the frame servo system:

[0095] During the processing, manufacturing and assembly process, the high-speed rotor of the control torque gyro inevitably has errors and uneven mass distribution, which leads to static and dynamic imbalance of the rotor. The resulting unbalanced disturbance is considered to be the main source of interference in the frame servo system. When the rotor rotates at high speed, the static unbalanced mass generated by its geometric center deviating from the inertia center will generate radial periodic centrifugal inertia force F on the high-speed shaft. s , its expression in space is as follows:

[0096]

[0097] Among them, U s =m s r ms , m s is the lumped static unbalanced mass, Ω is the speed of the high-speed rotor flywheel, is m s The initial phase angle.

[0098] When the rotor rotates at high speed, the dynamic unbalanced mass generated by the staggered main inertia axis and the rotation axis will generate an axial periodic inertia moment T on the frame axis. d , its expression in space is as follows:

[0099]

[0100] Among them, U d =m d r md h f , m d is the lumped dynamic unbalance mass, is m d The initial phase angle.

[0101] The centrifugal force generated by static imbalance will cause the radial friction torque fluctuation of the frame servo system, and the centrifugal torque generated by dynamic imbalance will cause the axial vibration of the system, thereby affecting the servo accuracy of the frame servo system. The speed fluctuation will be further transmitted to the spacecraft, and finally affect the attitude control performance of the spacecraft. d It can be seen from the expression that the unbalanced disturbance torque T dis a harmonic disturbance with known frequency but unknown amplitude and phase, which can be modeled as an exogenous system:

[0102]

[0103] Here, the state ξ is defined as

[0104] In addition, in order to smoothly estimate the unbalanced disturbance, it is necessary to ensure that the disturbance is observable. The speed equation of the system is combined with the disturbance model to obtain the following equation:

[0105]

[0106]

[0107] The observable matrix is Due to its full rank, T d Can be observed.

[0108] Analysis of nonlinear friction torque on the frame servo system: Friction torque is mainly caused by the relative motion of rotating and transmission parts such as bearings and conductive slip rings in the control torque gyro frame servo system, which can easily lead to steady-state errors, tracking lags and limit cycles in the system during speed regulation. Therefore, friction torque is one of the main factors affecting the servo accuracy of the system. In addition, gyro torque and cogging torque will also affect the servo accuracy of the frame servo system. However, the factors that produce them are complex, and it is difficult to obtain accurate model information for these disturbances.

[0109] For the case where the frame servo system has only a single harmonic disturbance d, a disturbance observer is designed to estimate the disturbance. The design is as follows:

[0110]

[0111] in, are the estimates of d and ξ respectively, z is an auxiliary variable, and the vector is the disturbance observer gain to be designed.

[0112] For the frame servo system with modelable disturbance d 1 and unmodelable disturbance d 2 Design an adaptive fine disturbance observer to estimate the disturbance:

[0113] Define the sliding mode variable: s = ω-ζ, where ζ satisfies the following dynamics:

[0114]

[0115] in, They are d 1, d 2 Estimator of , v = λ 1 sign(s) is the sliding mode term, scalar λ 0 and λ 1 is the dynamic gain to be designed.

[0116] Subtracting the system speed equation from the ζ dynamic equation, we can get the following equation:

[0117]

[0118] in, is the interference estimation error.

[0119] Based on the above derivation, the adaptive fine disturbance observer is designed as follows:

[0120]

[0121] in, are the estimates of ξ and β respectively, η is an auxiliary variable, and the vector Scalar K 2 and K 3 is the gain of the adaptive fine disturbance observer to be designed.

[0122] First, select the Lyapunov function: V 1 =s T s, when the gain λ 0 and λ 1 They are selected as: 0 ≥0, , it can be proved that: That is, the sliding mode variable s can converge to 0. Can be equivalent to λ 1 sign(s), that is:

[0123] Secondly, based on the fact that the sliding mode variable s can converge to 0, the Lyapunov function is selected: in: When the gain K 2 and K 3 They are selected as: K 2 >0,K 3 > 0, and the adaptive law is designed as follows:

[0124]

[0125] Among them, γ 0 is a positive constant, it can be proved that: It can converge to a bounded set in finite time.

[0126] According to the pole configuration principle, while ensuring that the poles of the adaptive fine disturbance observer are all located in the left half plane of the S domain, the observer gain K is further selected and determined. 1 , K 2 and K 3 , thus ensuring the estimation error and Consistently eventually bounded.

[0127] Combined with the multi-source disturbance estimation results, a finite-time current constraint controller is constructed, including:

[0128] Considering the ideal frame servo system model without multi-source interference, the speed tracking error e is defined as: 1 =ω r -ω, The error system model is established as follows:

[0129]

[0130] Among them, i q Satisfy the constraint condition |i q |<c.

[0131] Based on the error system model, a finite-time current constraint controller is designed as shown below:

[0132]

[0133] Among them, k 1 , k 2 and the penalty term l are adjustable positive parameters; 0<α 1 <1,

[0134] Based on the feedforward compensation of the adaptive fine disturbance observer and the feedback control of the finite time current constraint controller, a composite anti-disturbance controller is constructed to realize the anti-disturbance control of the control moment gyro frame servo system, including:

[0135] For the non-cascade control framework of the frame servo system, the composite control law designed based on the feedback control of the finite time current constraint and the feedforward compensation based on the adaptive fine disturbance observer is shown in the following formula:

[0136]

[0137] Based on the error system model, a suitable Lyapunov function is selected to prove the stability of the system and to prove that the q-axis current of the system satisfies the given current constraint.

[0138] Select the following Lyapunov candidate function:

[0139]

[0140] After taking the derivative of V, we find that when i q Satisfy the constraint |i q |<c, This indicates that the velocity tracking error e 1 is bounded. According to Russell's invariance theorem, when The error system is asymptotically stable under finite-time current constraint control, that is, the actual speed ω of the frame servo system can asymptotically stably track the given reference signal.

[0141] Consider a continuous homogeneous vector Its about expansion Homogeneity Prove that the following sufficient condition r 2 β>k+r 2 Satisfied by:

[0142] Then, the error system model is obtained:

[0143]

[0144] Among them, f 1 =e 2 , Its finite time current constraint controller u q The control is locally finite-time stable.

[0145] Example 2

[0146] This embodiment 2 provides a composite hierarchical anti-interference control method based on multi-source disturbance of the control moment gyro frame servo system, which is used for high-precision servo control of the control moment gyro frame servo system under multi-source disturbance, such as Figure 1 As shown, the method comprises the following steps:

[0147] S1. According to the working principle of the control torque gyro, considering the multi-source interference of the frame servo system during operation, a mathematical model of the frame servo system under the existence of multi-source interference is established;

[0148] S2. Classify, analyze and model the multi-source interferences suffered by the frame servo system in actual working conditions;

[0149] S3, designing a corresponding disturbance observer framework to estimate the disturbance for the case where the frame servo system has only a single modelable disturbance and has multiple sources of disturbance such as modelable and unmodelable disturbances;

[0150] S4. Based on the constructed system non-cascade control framework, a finite-time current constraint controller is designed in combination with disturbance estimation to simultaneously realize current protection and suppression of mismatched disturbances;

[0151] S5. Construct a composite anti-interference controller and select a suitable Lyapunov function to prove the stability of the system and prove that the q-axis current of the system satisfies the given current constraint.

[0152] in,

[0153] In step S1, the frame servo system with multiple interference sources is modeled as follows:

[0154]

[0155] It has been assumed that: the saturation of the motor core is ignored, the eddy current and hysteresis loss in the motor are not considered, and the current in the motor is a symmetrical three-phase sine wave. d and i q are the stator currents of the d-axis and q-axis respectively, u d and u q are the stator voltages of the d-axis and q-axis respectively, L d and L q are the stator inductances of the d-axis and q-axis respectively. The stator inductance of the surface-mounted permanent magnet synchronous motor satisfies L d =L q =L, R s is the stator resistance, ω is the rotor angular velocity, n p is the pole pair number, ψ f is the magnetic flux, J is the moment of inertia, and d represents the multi-source interference to the system. Here we consider: T d is the rotor unbalance disturbance, T f is the nonlinear friction torque, T g is the gyro torque and T c is the cogging torque. In addition, the torque coefficient k t satisfy

[0156] Typically, vector control methods are applied to frame servo systems. Specifically, the stator current is decoupled into the excitation component i by spatial coordinate transformation. d and torque component i q , thus achieving independent flux and torque control. In order to eliminate the coupling effect between the w and dq axis currents, the d axis reference current i d * Set to i d * = 0. If the controller of the d-axis current loop works in an ideal state, we can obtain i d =i d *= 0. Therefore, the system model (1) can be approximately simplified to the following form:

[0157]

[0158] Where L is the inductance of the frame servo system.

[0159] Step S2 further includes the following sub-steps:

[0160] S2.1. Analyze and model the rotor imbalance disturbance on the frame servo system.

[0161] During the processing, manufacturing and assembly, the high-speed rotor of the control torque gyro inevitably has errors and uneven mass distribution, which leads to static and dynamic imbalance of the rotor. The resulting unbalance disturbance is regarded as the main source of interference in the frame servo system. Figure 2 The schematic diagram of the static unbalance interference of the high-speed rotor of the control torque gyro is shown in the figure. When the rotor rotates at high speed, its geometric center deviates from the inertia center, and the static unbalanced mass generated will generate a radial periodic centrifugal inertia force F on the high-speed rotating shaft. s , its expression in space is as follows:

[0162]

[0163] Among them, U s =m s r ms , m s is the lumped static unbalanced mass, Ω is the speed of the high-speed rotor flywheel, is m s The initial phase angle.

[0164] Combination Figure 3 The schematic diagram of the dynamic unbalance interference of the high-speed rotor of the control torque gyro shown in the figure. When the rotor rotates at high speed, the dynamic unbalance mass generated by the staggered main inertia axis and the rotation axis will generate an axial periodic inertia moment T on the frame axis. d , its expression in space is as follows:

[0165]

[0166] Among them, U d =m d r md h f , m d is the lumped dynamic unbalance mass, is m d The initial phase angle.

[0167] The centrifugal force generated by static imbalance will cause the radial friction torque fluctuation of the frame servo system, and the centrifugal torque generated by dynamic imbalance will cause the axial vibration of the system, thereby affecting the servo accuracy of the frame servo system. The speed fluctuation generated will be further transmitted to the spacecraft, and finally affect the attitude control performance of the spacecraft. It can be seen from formula (4) that the unbalanced disturbance torque T d is a harmonic disturbance with known frequency but unknown amplitude and phase, which can be modeled as an exogenous system:

[0168]

[0169] Here, the state ξ is defined as

[0170] In addition, in order to smoothly estimate the unbalanced disturbance, it is necessary to ensure that the disturbance is observable. Combining the system speed equation (2) with the disturbance model (5), the following equation is obtained:

[0171]

[0172] Among them, the observable matrix is Due to its full rank, T d Can be observed.

[0173] S2.2. Analysis of nonlinear friction torque acting on the frame servo system.

[0174] Friction torque is mainly caused by the relative motion of rotating and transmission parts such as bearings and conductive slip rings in the control torque gyro frame servo system, which can easily lead to steady-state errors, tracking lags and limit cycles in the system during speed regulation. Therefore, friction torque is one of the main factors affecting the servo accuracy of the system.

[0175] In addition, gyroscopic torque and cogging torque will also affect the servo accuracy of the frame servo system. However, the factors that produce them are complex, and it is difficult to obtain accurate model information of these disturbances. This scheme divides multi-source disturbances into the following two categories based on whether the disturbance model information is known:

[0176] d=d 1 +d 2 (7)

[0177] Among them, d 1 is the rotor unbalance disturbance, which is a high-frequency harmonic disturbance that can be modeled; d 2 The lumped disturbances that cannot be modeled include: nonlinear friction torque, gyroscopic torque, and cogging torque. Assumption: The unmodeled disturbance d 2 Differentiable, There is an upper bound but the limit is unknown.

[0178] Step S3 further includes the following sub-steps:

[0179] S3.1. Design a disturbance observer to estimate the disturbance when the frame servo system has only a single harmonic disturbance d. The design is as follows:

[0180]

[0181] in, are the estimates of d and ξ respectively, z is an auxiliary variable, and the vector is the disturbance observer gain to be designed.

[0182] S3.2, for the frame servo system with modelable disturbance d 1 and unmodelable disturbance d 2 In this case, an adaptive fine disturbance observer is designed to estimate the disturbance.

[0183] Define the sliding mode variable: s = ω-ζ, where ζ satisfies the following dynamics:

[0184]

[0185] in, They are d 1 , d 2 Estimator of ν = λ 1 sign(s) is the sliding mode term, scalar λ 0 and λ 1 is the dynamic gain to be designed.

[0186] Subtracting the system speed equation (2) from the ζ dynamic equation (9), we can get the following equation:

[0187]

[0188] in, is the interference estimation error.

[0189] Based on the above derivation, the adaptive fine disturbance observer is designed as follows:

[0190]

[0191] in, are the estimates of ξ and β respectively, η is an auxiliary variable, and the vector Scalar K 2 and K 3 is the gain of the adaptive fine disturbance observer to be designed.

[0192] First, select the Lyapunov function: V 1 =s T s, when the gain λ 0and λ 1 They are selected as: 0 ≥0, , it can be proved that: That is, the sliding mode variable s can converge to 0. Can be equivalent to λ 1 sign(s), that is:

[0193] Secondly, based on the fact that the sliding mode variable s can converge to 0, the Lyapunov function is selected: in: When the gain K 2 and K 3 They are selected as: K 2 >0,K 3 > 0, and the adaptive law is designed as follows:

[0194]

[0195] Among them, γ 0 is a positive constant, it can be proved that: It can converge to a bounded set in finite time.

[0196] According to the pole configuration principle, while ensuring that the poles of the adaptive fine disturbance observer are all located in the left half plane of the S domain, the observer gain K is further selected and determined. 1 , K 2 and K 3 , thus ensuring the estimation error and Consistently eventually bounded.

[0197] In summary, based on the comprehensive classification and analysis of the multi-source disturbances suffered by the frame servo system, the unbalanced disturbance d 1 The interference observer (8) is designed to estimate the unmodeled aggregate interference d 2 , since it is difficult to obtain the perturbation d 2 The prior information of its derivative is used to estimate it by designing an adaptive sliding mode disturbance observer, in which the adaptive law (12) is designed to estimate Finally, combining the advantages of the disturbance observer and the adaptive sliding mode disturbance observer, an adaptive fine disturbance observer (11) is proposed to improve the accuracy of multi-source disturbance estimation for the frame servo system.

[0198] Step S4 further includes the following sub-steps:

[0199] S4.1. Considering the ideal frame servo system model without multi-source interference, define: speed tracking error e 1 =ωr -ω, The error system model is established as follows:

[0200]

[0201] Among them, i q Satisfy the constraint condition |i q |<c.

[0202] S4.2. Based on the error system model (13), a finite-time current constraint controller is designed as shown below:

[0203]

[0204] Among them, k 1 , k 2 and the penalty term l are adjustable positive parameters; 0≤α 1 <1, β>α 2 .

[0205] Step S5 further includes the following sub-steps:

[0206] S5.1. For the non-cascade control framework of the frame servo system, the composite control law designed based on the feedback control of the finite time current constraint and the feedforward compensation based on the adaptive fine disturbance observer is as shown in the following formula:

[0207]

[0208] S5.2. Based on the error system model (13), select a suitable Lyapunov function to prove the stability of the system and prove that the q-axis current of the system satisfies the given current constraint.

[0209] Select the following Lyapunov candidate function:

[0210]

[0211] After taking the derivative of (16), we find that when i q Satisfy the constraint |i q |<c, This indicates that the velocity tracking error e 1 is bounded. According to Russell's invariance theorem, when The error system (13) is asymptotically stable under the control of the finite time current constraint controller (14), that is, the actual rotation speed of the frame servo system can asymptotically stably track the given reference signal.

[0212] Furthermore, consider a continuous homogeneous vector Its about expansion Homogeneity Prove that the following sufficient condition r 2 β>k+r 2 Satisfied by:

[0213]

[0214] Then, the error system model is obtained:

[0215]

[0216] Among them, f 1 =e 2 , It is locally finite-time stable under the control of a finite-time current constraint controller (14).

[0217] Next, in order to verify the effectiveness of the composite layered anti-interference control method based on the multi-source disturbance of the control moment gyro frame servo system provided in this embodiment, a simulation experiment is carried out using MATLAB and a detailed description is given.

[0218] The control torque gyro frame servo system model provided in this embodiment comprehensively considers the influence of single modelable interference and multi-source interference such as modelable and non-modelable interference on the servo accuracy of the frame servo system, and adopts a finite-time current constraint composite anti-interference control strategy to achieve attenuation and suppression of multi-source mismatched disturbances, so that the following two-stage frame servo system has good servo performance, namely: the actual angular velocity tracks the reference value with high precision, and the q-axis current can meet the given current constraint to achieve overcurrent protection.

[0219] Phase 1: Startup

[0220] In the simulation experiment, we use the control torque gyro frame servo system model to verify the effectiveness of the proposed finite time current constraint composite anti-interference controller. The parameters used in the frame servo system model are: J = 0.001 kg·m 2 , L=0.0085H, R s =2.785Ω,ψ f =0.175Wb and n p =4. In addition, we set the reference speed ω r =2° / s, given a current constraint of 0.01A and a voltage saturation limit of 220V.

[0221] The design of the composite hierarchical anti-interference controller adopts the method proposed in this invention, in which the controller parameters should be adjusted by comprehensively considering the system stability, dynamic performance, current constraint satisfaction and robustness against multi-source disturbances. The control performance of the algorithm proposed in this invention is highly dependent on the selection of controller gain, in which the parameter K 1 , K 2 and K 3 The selection of needs to satisfy the pole placement principle to ensure the boundedness of the estimation error of the adaptive fine disturbance observer, and the adjustment parameter l will affect the strength of the constraint current. The controller parameters are set as: K 1 =[6.5145 0.0008] T , K 2 =15000,K 3 =1500,λ 0 =10,λ 1 =1,γ 0 =0.1, k 1 =10 9 , α 1 =3, k 2 =80,α 2 =1.3, l=1, c=0.01 and β=3.5.

[0222] Stage 2: Stage affected by multiple sources of disturbance

[0223] In the following simulation experiments, we will focus on the anti-interference ability and current constraint satisfaction of the proposed finite-time current-constrained composite anti-interference controller under multi-source disturbances to ensure the high-precision servo performance of the frame servo system. Using the system model parameters in stage 1, the reference speed, the given current constraints and controller parameters, and setting the rotor unbalance disturbance d 1 (Nm) = 5sin(200πt), that is, the matrices W and V are as follows:

[0224]

[0225] Setting 2 It is a slow-changing interference.

[0226] The following two types of interference will be taken into account in the simulation experiments at this stage:

[0227] Sinusoidal disturbance: When 0≤t<1s, d=5sin(200πt)Nm acts on the system;

[0228] Multi-source disturbance: When 1≤t≤2s, d=5sin(200πt)+5+0.008ω Nm acts on the system.

[0229] Based on the above parameters, the composite control strategy proposed by the present invention is simulated and verified through stages 1 and 2 respectively. Figure 4 , Figure 5 and Figure 6 .in, Figure 4 The schematic diagram shows the speed tracking error curve in the composite layered anti-interference control method based on multi-source disturbances of this system. Figure 5 The schematic diagram of the q-axis current curve in the composite layered anti-interference control method based on multi-source disturbances of this system is shown. Figure 6 The schematic diagram of the multi-source disturbance estimation and its error curve of the system is shown. It can be seen from the simulation schematic diagram that the proposed composite hierarchical anti-interference controller has good transient and steady-state performance, the proposed adaptive fine disturbance observer can realize the accurate estimation of unknown slow-varying disturbances in the presence of multi-source interference, and the interference estimation results can be introduced into the design process of the composite control law proposed by the present invention, so as to realize the attenuation and suppression of multi-source mismatched interference by using the proposed finite time current constraint composite anti-interference control strategy, ensure the high-precision servo performance of the frame servo system, and at the same time, the q-axis current can meet the given current constraint to achieve overcurrent protection.

[0230] The above analysis proves the effectiveness of the composite hierarchical anti-interference control strategy based on multi-source disturbance of the control moment gyro frame servo system provided in this embodiment.

[0231] Example 3

[0232] This embodiment 3 provides a non-transitory computer-readable storage medium, wherein the non-transitory computer-readable storage medium is used to store computer instructions. When the computer instructions are executed by a processor, the anti-interference control method for the control moment gyro frame servo system as described above is implemented. The method includes:

[0233] According to the working principle of the control moment gyro, considering the multi-source interference of the frame servo system during operation, the mathematical model of the frame servo system under the existence of multi-source interference is established.

[0234] Based on the mathematical model of the frame servo system, the multi-source disturbances to which the frame servo system is subjected in actual working conditions are classified, including rotor unbalance disturbances that can be modeled and lumped disturbances that cannot be modeled.

[0235] According to the classification results of multi-source interference, an adaptive fine interference observer is constructed to estimate the multi-source interference;

[0236] Combining the multi-source interference estimation results, a finite-time current constraint controller is constructed to achieve current protection and suppression of mismatched interference.

[0237] Based on the feedforward compensation of adaptive fine disturbance observer and the feedback control of finite time current constraint controller, a composite anti-disturbance controller is constructed to realize the anti-disturbance control of control moment gyro frame servo system.

[0238] Example 4

[0239] This embodiment 4 provides a computer program product, including a computer program. When the computer program is run on one or more processors, it is used to implement the anti-interference control method of the control moment gyro frame servo system as described above. The method includes:

[0240] According to the working principle of the control moment gyro, considering the multi-source interference of the frame servo system during operation, the mathematical model of the frame servo system under the existence of multi-source interference is established.

[0241] Based on the mathematical model of the frame servo system, the multi-source disturbances to which the frame servo system is subjected in actual working conditions are classified, including rotor unbalance disturbances that can be modeled and lumped disturbances that cannot be modeled.

[0242] According to the classification results of multi-source interference, an adaptive fine interference observer is constructed to estimate the multi-source interference;

[0243] Combining the multi-source interference estimation results, a finite-time current constraint controller is constructed to achieve current protection and suppression of mismatched interference.

[0244] Based on the feedforward compensation of adaptive fine disturbance observer and the feedback control of finite time current constraint controller, a composite anti-disturbance controller is constructed to realize the anti-disturbance control of control moment gyro frame servo system.

[0245] Example 5

[0246] This embodiment 5 provides an electronic device, including: a processor, a memory, and a computer program; wherein the processor is connected to the memory, the computer program is stored in the memory, and when the electronic device is running, the processor executes the computer program stored in the memory, so that the electronic device executes instructions for implementing the anti-interference control method for the control moment gyro frame servo system as described above, the method comprising:

[0247] According to the working principle of the control moment gyro, considering the multi-source interference of the frame servo system during operation, the mathematical model of the frame servo system under the existence of multi-source interference is established.

[0248] Based on the mathematical model of the frame servo system, the multi-source disturbances to which the frame servo system is subjected in actual working conditions are classified, including rotor unbalance disturbances that can be modeled and lumped disturbances that cannot be modeled.

[0249] According to the classification results of multi-source interference, an adaptive fine interference observer is constructed to estimate the multi-source interference;

[0250] Combining the multi-source interference estimation results, a finite-time current constraint controller is constructed to achieve current protection and suppression of mismatched interference.

[0251] Based on the feedforward compensation of adaptive fine disturbance observer and the feedback control of finite time current constraint controller, a composite anti-disturbance controller is constructed to realize the anti-disturbance control of control moment gyro frame servo system.

[0252] Although the above describes the specific implementation mode of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative work on the basis of the technical solution disclosed in the present invention should be included in the scope of protection of the present invention.

Claims

1. An anti-interference control method for a control moment gyro frame servo system, Features: According to the working principle of the control moment gyro, considering the multi-source interference of the frame servo system during operation, the mathematical model of the frame servo system under the existence of multi-source interference is established. Based on the mathematical model of the frame servo system, the multi-source disturbances to which the frame servo system is subjected in actual working conditions are classified, including rotor unbalance disturbances that can be modeled and lumped disturbances that cannot be modeled. According to the classification results of multi-source interference, an adaptive fine interference observer is constructed to estimate the multi-source interference; Combining the multi-source interference estimation results, a finite-time current constraint controller is constructed to achieve current protection and suppression of mismatched interference. Based on the feedforward compensation of adaptive fine disturbance observer and the feedback control of finite time current constraint controller, a composite anti-disturbance controller is constructed to realize the anti-disturbance control of the control moment gyro frame servo system. According to the classification results of multi-source interference, an adaptive fine interference observer is constructed to estimate the multi-source interference, including: For the case where the frame servo system has only a single harmonic disturbance d, a disturbance observer is designed to estimate the disturbance. The design is as follows: in, are the estimates of d and state ξ respectively, z is an auxiliary variable, and the vector is the disturbance observer gain to be designed; ω is the rotor angular velocity; where the state ξ is defined as V = [1 0]; Ω is the speed of the high-speed rotor flywheel; J is the moment of inertia; torque coefficient k t satisfy i q is the stator current of the q axis; T d is the rotor unbalance disturbance torque; n p is the pole pair number, ψ f is the magnetic link; For the frame servo system with modelable disturbance d 1 and unmodelable disturbance d 2 Design an adaptive fine disturbance observer to estimate the disturbance: Define the sliding mode variable: s = ω-ζ, where ζ satisfies the following dynamics: in, They are d 1 ,d 2 Estimator of , v = λ 1 sign(s) is the sliding mode term, scalar λ 0 and λ 1 is the dynamic gain to be designed; Subtracting the system speed equation from the ζ dynamic equation, we can get the following equation: in, is the interference estimation error; Then, the design of the adaptive fine disturbance observer is as follows: Among them, are the estimators of ξ and β respectively, η is the auxiliary variable, and the vector scalar K 2 and K 3 are the gains of the adaptive fine disturbance observer to be designed; Select the Lyapunov function: V 1 =s T s, when the gain λ 0 and λ 1 They are selected as: 0 ≥0, , it can be proved that: That is, the sliding mode variable s can converge to 0; due to Can be equivalent to λ 1 sign(s), that is: On the basis that it has been proved that the sliding mode variable s can converge to 0, the Lyapunov function is selected: in: When the gain K 2 and K 3 They are selected as: K 2 >0,K 3 >0, the adaptive law is: Among them, γ 0 is a normal number, It can converge to a bounded set in a finite time; Combined with the multi-source disturbance estimation results, a finite-time current constraint controller is constructed, including: Considering the ideal frame servo system model without multi-source interference, the speed tracking error e is defined as: 1 =ω r -ω, The error system model is established as follows: Among them, i q Satisfy the constraint condition |i q |<c; L is the inductance of the frame servo system. Based on the error system model, a finite-time current constraint controller is designed as shown below: Among them, k 1 , k 2 and the penalty term l are adjustable positive parameters; 0<α 1 <1, β≥α 2 ;u q is the stator voltage of the q axis, R s is the stator resistance.

2. The anti-interference control method for the control moment gyro frame servo system according to claim 1, It is characterized in that The mathematical model of the frame servo system under the existence of multi-source interference is established, including: Among them, i d is the stator current of the d-axis; T f is the nonlinear friction torque, T g is the gyro torque and T c is the cogging torque; u d is the stator voltage of the d-axis; L d and L q are the stator inductances of the d-axis and q-axis respectively.

3. The anti-interference control method for the control moment gyro frame servo system according to claim 2, It is characterized in that Based on the mathematical model of the frame servo system, the multi-source disturbances suffered by the frame servo system in actual working conditions are classified, including modelable rotor unbalance disturbances and unmodelable lumped disturbances, including: According to whether the disturbance model information is known, the multi-source disturbances are divided into the following two categories: d=d 1 +d 2 ; Among them, d 1 is the rotor unbalance disturbance, which is a high-frequency harmonic disturbance that can be modeled; d 2 Lumped disturbances that are considered unmodelable include: nonlinear friction torque, gyroscopic torque, and cogging torque; Analyze and model rotor unbalance disturbances: When the rotor rotates, the static unbalanced mass generated by the deviation of its geometric center from the inertia center will generate a radial periodic centrifugal inertia force F on the shaft. s : Among them, U s =m s r ms , m s is the lumped static unbalanced mass, is m s The initial phase angle of When the rotor rotates, the dynamic unbalanced mass generated by the staggered main inertia axis and the rotation axis will generate an axial periodic rotor unbalance disturbance torque T on the frame axis. d : Among them, U d =m d r md h f , m d is the lumped dynamic unbalance mass, is m d The initial phase angle of Rotor unbalance disturbance torque T d is a harmonic disturbance with known frequency but unknown amplitude and phase, which can be modeled as an exogenous system: The speed equation of the system is combined with the disturbance model to obtain the following equation: Among them, the observable matrix is Due to its full rank, T d Can be observed.

4. The anti-interference control method for the control moment gyro frame servo system according to claim 3, It is characterized in that Based on the feedforward compensation of the adaptive fine disturbance observer and the feedback control of the finite time current constraint controller, a composite anti-disturbance controller is constructed to realize the anti-disturbance control of the control moment gyro frame servo system, including: For the non-cascade control framework of the frame servo system, a composite control law is designed based on feedback control based on finite-time current constraints and feedforward compensation based on adaptive fine disturbance observer:

5. A control system for an anti-interference control of a control moment gyro frame servo system based on the anti-interference control method for the control moment gyro frame servo system as claimed in claim 1, It is characterized in that include: The first building module is used to analyze the working principle of the control moment gyro, consider the multi-source interference suffered by the frame servo system during operation, and establish a mathematical model of the frame servo system under the existence of multi-source interference; A classification module is used to classify the multi-source disturbances suffered by the frame servo system in actual working conditions based on the mathematical model of the frame servo system, including rotor unbalance disturbances that can be modeled and lumped disturbances that cannot be modeled; An estimation module, used for constructing an adaptive fine interference observer to estimate the multi-source interference according to the classification result of the multi-source interference; The second building module is used to combine the multi-source interference estimation results to build a finite time current constraint controller to achieve current protection and suppression of mismatch interference; The control module is used to construct a composite anti-interference controller based on feedforward compensation of an adaptive fine disturbance observer and feedback control of a finite-time current constraint controller to achieve anti-interference control of a control moment gyro frame servo system.

6. A non-transitory computer-readable storage medium, It is characterized in that The non-transitory computer-readable storage medium is used to store computer instructions. When the computer instructions are executed by the processor, the anti-interference control method of the control moment gyro frame servo system as described in any one of claims 1-4 is implemented.

7. A computer program product, It is characterized in that It comprises a computer program, which, when running on one or more processors, is used to implement the anti-interference control method of the control moment gyro frame servo system as described in any one of claims 1-4.

8. An electronic device, It is characterized in that include: A processor, a memory and a computer program; wherein the processor is connected to the memory, the computer program is stored in the memory, and when the electronic device is running, the processor executes the computer program stored in the memory so that the electronic device executes instructions for implementing the anti-interference control method of the control torque gyro frame servo system as described in any one of claims 1-4.

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