144 results about "Terminal sliding mode" patented technology

The invention provides an unmanned surface vessel recursive terminal sliding mode control method based on a novel disturbance observer, and relates to the technical field of unmanned surface vessels. The method comprises the following steps: firstly, designing a fixed time disturbance observer (FTDO) to suppress model uncertainty and adverse effects of external disturbance; and then an adaptive fixed time disturbance observer (AFTDO) is developed, and the adaptive law does not need lumped disturbance priori knowledge. Different from an existing fast non-singular terminal sliding mode surface (FNTSMs) which adopts a linear sliding mode (LSM) to avoid singularity, the method innovatively constructs a recursive terminal sliding mode surface (RTSM), thoroughly avoids singularity through a recursive structure, and remarkably improves convergence precision and speed near a balance point at the same time. A fixed-time recursive terminal sliding mode controller (FTRTSMC) is designed based on a lumped disturbance estimated value of the AFTDO, and it is strictly ensured that a trajectory tracking error converges to zero within fixed time (convergence time is irrelevant to an initial state).

The invention discloses a quadrotor unmanned aerial vehicle finite time sliding mode attitude control method based on reinforcement learning, and the method comprises the steps: building a quadrotor unmanned aerial vehicle attitude dynamic model considering external disturbance and model uncertainty, and rewriting the quadrotor unmanned aerial vehicle attitude dynamic model into a standard state equation form; a controller nominal item based on a nonsingular integral terminal sliding mode method is designed, an arrival control law item containing a time-varying matrix is designed, and the sum of the arrival control law item and the nominal item is an attitude controller; based on the reinforcement learning principle, an extended Markov decision process is constructed, a corresponding state set, an action set, action implementation mapping, a reward function and the like are designed, and a time-varying matrix is obtained through reinforcement learning training and is set online. According to the method, the dynamic performance and the steady-state performance of the system are effectively improved, and meanwhile high robustness is achieved under turbulence disturbance.

The invention discloses a quadrotor unmanned aerial vehicle trajectory tracking control method, a quadrotor unmanned aerial vehicle and a storage medium, and relates to the technical field of unmanned aerial vehicle control. The method is technically characterized by comprising the following steps: firstly, providing a fast terminal sliding mode disturbance observer for unknown disturbance of a system so as to realize accurate estimation of the disturbance within preset time; then designing a preset time fast terminal sliding mode controller based on disturbance estimation information, and further weakening a buffeting phenomenon of the system by using a saturation function; finally, based on a Lyapunov function method, it is proved that the system can achieve global predetermined time stability; according to the method, predefined time convergence of the trajectory tracking error of the quad-rotor unmanned aerial vehicle under unknown disturbance can be realized, the upper bound of the stabilization time can be randomly preset in a physical limitation range, the rapidity of the system is ensured, buffeting is eliminated, and the stability of the system is improved.

The invention provides a permanent magnet synchronous motor sliding mode control method and system based on disturbance compensation, and the method comprises the steps: constructing a first motor state equation based on a permanent magnet synchronous motor mathematical model containing disturbance; secondly, on the basis of a sliding mode control theory, a novel adaptive reaching law and a non-singular fast terminal sliding mode surface are constructed, stability proving is completed, and the fast convergence capability is analyzed; designing a novel speed ring controller through the state equation, the reaching law and the sliding mode surface; designing a sliding mode disturbance observer for a disturbance part in the speed loop controller; and finally, carrying out FOC speed regulation control on the permanent magnet synchronous motor by using the designed speed ring controller and the disturbance observer. Compared with an existing well-known sliding mode control scheme, the hybrid control method of the speed loop controller and the sliding mode disturbance observer is adopted, system buffeting is effectively weakened, meanwhile, the dynamic response speed is considered, and the system robustness is improved.

The invention provides an anti-disturbance unmanned aerial vehicle trajectory tracking control method, system and device and a medium. The method comprises the following steps: establishing a six-degree-of-freedom rigid body dynamic model of a four-rotor unmanned aerial vehicle; selecting an unmanned aerial vehicle feasible trajectory of the kinetic model as an expected trajectory, and introducing a coupling attitude; designing a position loop control law, generating a virtual control force based on a smooth terminal sliding mode control surface, and calculating an actual thrust; designing an attitude loop control law, representing an attitude error based on Lie group SO (3), constructing an attitude tracking controller with a stable global index, and outputting a control torque; constructing a four-order state observer to estimate the angular velocity and the angular acceleration of the coupling attitude, and replacing a true value with an estimated value to participate in control law calculation; thrust and control torque are converted into thrust input of the unmanned aerial vehicle, the unmanned aerial vehicle is driven to track an expected trajectory, and the problems that in trajectory tracking control of the four-rotor unmanned aerial vehicle, dependence on position acceleration measurement is high, noise is amplified through differential derivation, disturbance rejection is weak, and real-time calculation burden is large are solved.

The invention discloses a quadrotor unmanned aerial vehicle attitude fault-tolerant control method. The method comprises the following steps: S1, establishing a tracking error dynamic model of a quadrotor unmanned aerial vehicle attitude system; s2, designing a reduced-order fixed-time expansion state observer; s3, constructing an adaptive preset performance function; s4, designing a fast nonsingular terminal sliding mode surface and a fixed time reaching law based on an adaptive preset performance function and the lumped disturbance estimated value, and generating a posture virtual control quantity; and S5, according to the mapping relation between the attitude virtual control quantity and the attitude loop control moment, performing inverse solution to obtain the attitude loop control moment, and inputting the control moment into an attitude actuator to enable the attitude angle tracking error to converge to be near a balance point within a fixed time. Compared with the prior art, the four-rotor unmanned aerial vehicle attitude fault-tolerant control method has the advantages that strict constraint on attitude system response under the actuator fault condition is provided, it is ensured that unmanned aerial vehicle tracking errors meet preset transient state and steady state performance constraints, and meanwhile the vulnerability problem of preset performance is effectively avoided.

The application discloses a quad-rotor unmanned aerial vehicle attitude fault-tolerant control method considering unknown wind disturbance, and relates to the field of unmanned aerial vehicle attitude control design; the method can effectively cope with unknown wind disturbance, actuator partial failure and deviation faults. In the application, unknown wind disturbance and deviation faults are regarded as total disturbance, an improved disturbance compensator is designed by using an adaptive mechanism for the total disturbance, and the size of switching gain is adjusted online according to the control accuracy requirement, so that the waste of controller output energy caused by excessively large switching gain is avoided. For actuator partial failure, a failure factor compensator designed based on an adaptive method enables the unmanned aerial vehicle to timely process faults and recover normal trajectory. An attitude controller is designed by using a non-singular fast terminal sliding mode control technology, so that the robustness and fast response characteristics are ensured, the unmanned aerial vehicle can timely process faults, the fault tolerance of the unmanned aerial vehicle is enhanced, and the flight safety of the unmanned aerial vehicle is improved.

The invention provides a Markov jump-based mechanical arm preset time trajectory tracking control method, which comprises the following steps of: calculating a trajectory tracking error by establishing a two-degree-of-freedom mechanical arm dynamic model with a Markov jump characteristic; a trajectory tracking error is subjected to nonlinear transformation, a nonsingular terminal sliding mode surface is constructed in combination with a preset convergence time upper limit function, and then a control torque is synthesized through an equivalent control item and a robust switching item containing a sliding mode surface sign function and a switching gain to drive a mechanical arm. And the trajectory tracking error is difficult to converge in the preset time.

The invention particularly relates to a four-rotor unmanned aerial vehicle trajectory tracking anti-interference control method and system. The four-rotor unmanned aerial vehicle trajectory tracking anti-interference control method comprises the following steps: establishing a four-rotor unmanned aerial vehicle double-loop control framework and a kinetic model, solving an error amount of a preset performance characteristic, constructing an extended state observer, regarding disturbance as a system state, estimating system uncertainty and external disturbance on line, and generating a compensation amount; a sliding mode controller is designed by taking sliding mode control as a core and combining an extended state observer, a preset performance error amount, a non-singular fast terminal sliding mode surface and an approaching rate, and high-precision trajectory tracking and anti-interference control are realized. According to the four-rotor unmanned aerial vehicle trajectory tracking anti-interference control method and system, high-precision trajectory tracking is achieved, the problem of collision or out-of-control caused by too large position errors can be remarkably reduced, the robustness to complex interference such as sudden change wind speed is remarkably improved, and the dynamic response time is shortened; and the method has low requirements on boundary conditions and is suitable for various small four-rotor unmanned aerial vehicles.

The invention discloses an underwater manipulator trajectory tracking finite time sliding mode controller design method, a sliding mode controller and a control system, and belongs to the technical field of underwater robot control. Comprising the steps that a nonsingular terminal sliding mode surface control framework is constructed, the framework fuses factors such as system model uncertainty, external disturbance, output constraint and input saturation, and a foundation is laid for accurate control; in order to ensure that a system state is always in a time-varying constraint boundary in a complex marine environment, a time-varying barrier Lyapunov function is combined with sliding mode control, tracking error constraint is converted into sliding mode surface constraint through mathematical conversion, and effective constraint on the system state is realized through strict derivation and analysis; besides, a finite time auxiliary control system with a dynamic compensation strategy is designed for the problem of input saturation caused by physical limitation of the actuator, trajectory errors can be rapidly restrained, and the accuracy and stability of trajectory tracking of the underwater manipulator are remarkably improved.

The invention relates to a trajectory tracking control method and system based on a predefined time observer and a neural network. The method comprises the following steps: defining a trajectory tracking error and deriving to obtain an error derivative; constructing a predefined time observer, estimating a state and composite disturbance which cannot be directly measured by the controlled system, and converging an observation error within a preset time to obtain a state estimation result; constructing a non-singular fast terminal sliding mode variable; carrying out online approximation by adopting a neural network, updating the weight of the neural network in real time based on the sliding mode variable, and outputting a compensation item through the neural network; and combining the state estimation result, the sliding mode variable and the compensation item to construct a trajectory tracking control law, and applying the trajectory tracking control law to a controlled system, so that a trajectory tracking error is converged to zero or a preset neighborhood within a preset time. The stable convergence of the trajectory tracking error within the predefined time can be realized, and the dynamic response performance and the tracking precision of the system are improved.

The invention discloses a linear drive continuous mechanical arm fixed time impedance control method based on a non-singular fast terminal sliding mode, and the method comprises the steps: firstly, building a dynamic model of a linear drive continuous mechanical arm; secondly, designing an impedance model based on expected inertia, damping and rigidity, and representing an impedance error; and finally, a linear drive continuous type mechanical arm fixed time impedance control system is designed, the control system comprises a fixed time disturbance observer for estimating external unknown disturbance and unmodeled dynamics and a singular avoiding piecewise function for eliminating control law singularity, and an impedance control law is designed through a non-singular fast terminal sliding mode method. The linear drive continuous mechanical arm can achieve stable transition between free motion and a contact environment, and has high-precision and high-robustness compliant control capacity.

The application discloses a multi-power unit high-speed train control method, and relates to the technical field of train control.The method comprises the following steps: performing stress analysis on a multi-power unit high-speed train to determine a high-speed train dynamics model; determining a discrete-time nonlinear model based on the high-speed train dynamics model; constructing control force and control force change rate constraints; converting the discrete-time nonlinear model to obtain a dynamic linearization data model; designing a parameter estimation algorithm and an adaptive extended state observer; designing a discrete-time terminal sliding mode function and a hyperbolic curve type reaching law; determining a data-driven terminal sliding mode control scheme based on the dynamic linearization data model, the parameter estimation algorithm, the adaptive extended state observer, the discrete-time terminal sliding mode function and the hyperbolic curve type reaching law; and performing tracking control operation on the multi-power unit high-speed train by using the data-driven terminal sliding mode control scheme.The application improves the control precision of high-speed train operation while reducing the sliding mode chattering.

The application discloses an anti-unwinding flexible spacecraft attitude tracking composite control method, first, based on the quaternion method, a flexible spacecraft attitude tracking error kinematics and dynamics model is established; then, the flexible accessory vibration mode, external environmental disturbance and model uncertainty are regarded as a lumped disturbance, a generalized proportional integral observer is designed, and the lumped disturbance is observed and estimated; finally, a non-singular terminal sliding mode surface is constructed, the lumped disturbance observation and estimation compensation of the generalized proportional integral observer is taken as a feedforward signal, and a feedforward-feedback anti-unwinding attitude tracking composite controller is designed. Through determining appropriate control gain, the closed-loop attitude tracking error system is globally finite time stable, and the anti-unwinding effect can be realized. The application can realize finite time attitude tracking of the flexible spacecraft, has high attitude tracking precision and strong robustness.

The application provides a water surface and underwater heterogeneous collaborative control method and device based on a preset time disturbance observer, and the control method mainly comprises the following steps: a water surface unmanned ship controller calculates an expected control torque according to a specified expected trajectory, actual state information of the unmanned ship body and a compensation value obtained by an observer; a underwater unmanned vehicle controller calculates an expected control torque according to an expected trajectory obtained by a guidance method, actual state information of the water surface unmanned ship, actual state information of the underwater unmanned vehicle body and the compensation value obtained by the observer; and the water surface unmanned ship and the underwater unmanned vehicle are collaboratively controlled in a heterogeneous mode. The application combines vertical projection and line-of-sight method to complete the guidance of the water surface and underwater heterogeneous collaborative control; the preset time disturbance observer is used to estimate external disturbance, and the disturbance is compensated in the controller to improve the anti-interference ability of the system; and the improved adaptive integral terminal sliding mode control method improves the robustness and rapidity of the system while increasing the tracking accuracy of the system.

The invention belongs to the technical field of four-rotor unmanned aerial vehicle control systems, and particularly relates to a nonsingular terminal sliding mode and second-order linear active disturbance rejection attitude control method, which comprises the following steps of S1, integrating flight attitude data of a four-rotor unmanned aerial vehicle; s2, establishing a kinetic model for describing the four-rotor unmanned aerial vehicle; s3, designing a nonsingular fast terminal sliding mode controller; s4, adding a second-order linear active disturbance rejection controller; and S5, proving the stability of the Lyapunov. The non-singular terminal sliding mode is combined with the improved second-order linear active-disturbance-rejection controller, it can be guaranteed that a quad-rotor unmanned aerial vehicle control system has the excellent performance such as quick response, robustness and higher tracking precision, and it is convenient for the quad-rotor unmanned aerial vehicle to keep the attitude stable in real time.

The invention relates to a hierarchical terminal sliding-mode control method of a quadrotor unmanned aerial vehicle suspension system based on preset performance, which can eliminate load swing while lifting an unmanned aerial vehicle to a target position, and is based on a kinetic model of the quadrotor unmanned aerial vehicle suspension system added with external interference. Firstly, a preset performance function is utilized to convert system errors into a non-limited system, then the system is divided into a height subsystem and a displacement and swing angle coupling subsystem, a terminal sliding mode controller is designed for the height subsystem, a layered terminal sliding mode controller is designed for the displacement and swing angle coupling subsystem, and an adaptive law is designed on the basis of the terminal sliding mode controller and the layered terminal sliding mode controller. Finally, the controller enables the unmanned aerial vehicle hanging system to arrive at a target point in an expected track, rapid swing elimination is achieved, under the condition that pulse interference is added, it is verified that the robustness of the controller is high, and the actual hoisting requirement for positioning and swing elimination can be met.

The application discloses a path tracking control method for a man-machine co-driving type intelligent vehicle, and steps are as follows: a vehicle path tracking error model is established, and a hierarchical control architecture is constructed, the hierarchical control architecture comprising an upper controller and a lower controller; the upper controller is configured to: in a human driving mode, generating a first front wheel steering angle through a two-point preview driver model, and in an automatic driving mode, generating a second front wheel steering angle through an automatic driving controller fusing a radial basis function neural network, a heuristic reinforcement adjustment mechanism and a non-singular fast terminal sliding mode control; the lower controller is configured to: driving a finite state machine to switch the driving mode based on a driving risk assessment index, and performing weighted fusion on the first front wheel steering angle and the second front wheel steering angle in a driving authority transition stage to output a final front wheel steering angle control instruction; the application solves the contradiction between path tracking precision and chattering, switching safety and comfort, and is suitable for man-machine collaborative control of an intelligent vehicle under multiple working conditions.

The invention discloses an automobile torque and rotating speed cooperative control method and system for an intelligent chassis framework, and the method employs a hierarchical control strategy, and specifically comprises the following steps: firstly, building a vehicle dynamics model and a PMSM mathematical model; the upper layer constructs an MPC trajectory tracking model based on a vehicle dynamics model, predicts the time domain to be adjusted along with the vehicle speed and the road curvature, calculates the additional yawing moment, and completes torque distribution in combination with a minimum tire load rate target; the lower layer is based on a PMSM mathematical model, a rotating speed controller is designed through non-singular fast terminal sliding mode control to track the reference rotating speed, a load observer is designed through high-order fast terminal sliding mode control to estimate and feed back external load torque, rotating speed deviation is synthesized through a rotating speed proportional synchronous controller and compensated, and rotating speed proportional synchronization of all wheels is achieved. Through cooperative control of the torque and the rotating speed, the trajectory tracking precision and the driving stability of the intelligent chassis architecture automobile are effectively improved, the control robustness is high, and the method is suitable for various working conditions.

The invention provides a control system and an anti-disturbance method of an electromagnetic bearing, a rotor position outer ring is controlled by a non-singular fast terminal sliding mode controller, external disturbance borne by the system is estimated in real time by introducing a non-linear disturbance observer, and an estimation result is fed back to a position controller for compensation; the input of the position controller is the difference value between the given position and the feedback position of the magnetic bearing rotor, and the output value is the reference value of the current loop control current; a stator coil inner ring is controlled by a nonsingular fast terminal sliding mode controller, input values of the controller comprise a current bias value + a current reference value output by a position ring and a current bias value-a current reference value output by the position ring, and an output quantity is a driving PWM signal duty ratio of a magnetic bearing stator coil; driving the PWM signal to be output to the power amplifier; the power amplifier supplies power to the stator coil; the axial thrust load sudden change anti-disturbance capability can be enhanced, it is ensured that when the thrust load suddenly changes, the magnetic bearing maintains stable suspension of the rotor, and anti-disturbance control is achieved.

The invention discloses a Mecanum wheel mobile robot trajectory tracking control method and device based on an adaptive power reaching law terminal sliding mode, and the method comprises the steps: 1), building a kinematics and dynamics model for a Mecanum wheel mobile robot; (2) designing a nonsingular terminal sliding mode surface and an adaptive power reaching law according to the mobile robot model established in the step (1) so as to realize dynamic adjustment of switching gain; 3) according to the sliding mode surface and the reaching law designed in the step 2, designing an adaptive power reaching law terminal sliding mode control algorithm suitable for the Mecanum wheel mobile robot; and 4) based on the Lyapunov stability theory, proving that the control algorithm designed in the step 3 can enable the system state to converge to a balance point within finite time, and performing simulation on an MATLAB / Simulink platform to verify the effectiveness of the control algorithm in trajectory tracking control of the Mecanum wheel mobile robot. According to the method, the trajectory tracking control precision of the Mecanum wheel mobile robot and the adaptability of the Mecanum wheel mobile robot under complex working conditions can be remarkably improved.

The invention relates to the technical field of particle swarm optimization, in particular to a terminal sliding mode phase synchronization control method and system based on improved particle swarm optimization. The method comprises the steps of performing phase synchronization on a fundamental wave voltage component of a three-phase voltage based on a terminal sliding mode; performing stability analysis on the terminal sliding mode based on phase synchronization; optimizing a parameter vector of the terminal sliding mode by adopting a particle swarm optimization algorithm, wherein the parameter vector comprises construction of a phase synchronization performance fitness function and parameter setting of the terminal sliding mode; and outputting a global optimal parameter. According to the scheme, the terminal sliding mode controller is innovatively adopted to achieve precise synchronization of harmonic distortion voltage phases, a stable synchronization state is achieved within a fixed time, strong interference resistance is achieved after the terminal sliding mode controller enters a sliding mode surface, and the external disturbance resistance is greatly improved.

The invention discloses a novel adaptive terminal sliding mode reaching law-based sliding mode control method for a grid-forming inverter, and the method comprises the steps: 1, collecting inverter side current and voltage and grid side current, and calculating the dq-axis components of the inverter side current and voltage and the grid side current through coordinate transformation; 2, calculating active power P and reactive power Q output by the inverter and active power Pf and reactive power Qf after filtering by using the dq-axis components uod and uoq of the inverter-side voltage and the dq-axis components iod and ioq of the grid-side current; 3, calculating a coordinate transformation angle theta and voltage command values uodref and uoqref of the dq axis of the voltage loop; 4, calculating dq-axis current instruction values idref and iqref of a current loop according to the uodref, the uoqref and a voltage loop sliding mode controller; and 5, according to the idref, the iqref and the current loop sliding mode controller, calculating d-axis and q-axis voltage wave sending instructions udref and uqref, and generating an inverter driving signal through modulation. According to the invention, the harmonic distortion rate of the grid-connected current of the inverter can be reduced, and the dynamic response speed and the anti-interference performance of the grid-forming inverter can be improved.

The application discloses a communication-restricted multi-agent tracking control method for trains, which comprises the following steps: S1, for a high-speed train dynamics model, a train formation dynamics model is designed; S2, a non-singular sliding mode surface is designed, which is brought into a dynamics equation, an equivalent control law and a total control law are designed; S3, a fixed threshold strategy is designed based on a control input signal error, and an event trigger condition is constructed; S4, through information interaction of adjacent vehicles, unmeasured states are estimated by using local measurable states, full-state feedback is provided for a controller, and a distributed observer is designed; the application has the beneficial effects that an improved terminal sliding mode surface is designed by using a non-singular terminal sliding mode surface, wherein the non-singular terminal sliding mode surface is a coprime odd number, fraction exponent irreducibility is ensured, periodic oscillation is avoided, and the singularity problem of traditional sliding mode control in time is eliminated by the fraction exponent term.

The invention belongs to the technical field of power equipment control, and discloses a control method of a grid-forming type photovoltaic power generation system, which comprises the following steps: acquiring system state variables capable of representing front-stage and rear-stage operation states; a variable power point tracking algorithm is adopted to determine a control reference of the direct current chopper, and a non-singular fast integral terminal sliding mode function is set; a virtual synchronous generator algorithm is adopted to determine a control reference of an inverter, a non-singular fast terminal sliding mode function used for voltage outer loop control and a non-singular integral terminal sliding mode function used for current inner loop control are set, and a driving signal is generated through each sliding mode function-sliding mode reaching law-sliding mode control law. And completing the control of each stage of converter. The control method effectively solves the problem of oscillation caused by sudden load change, has good robustness and rapid response, and is suitable for a port photovoltaic power generation system, the invention further provides a non-transient readable recording medium storing a program of the method and a system comprising the medium, and the program can be called and the method can be executed through a processing circuit.

The invention discloses an accurate and rapid fuzzy control method for a maritime lightering device, and the method comprises the following steps: S1, building a maritime lightering device kinematics equation based on kinematics analysis; s2, obtaining a basic driving signal of each execution mechanism by solving an inverse solution equation; s3, constructing a self-adaptive terminal sliding mode surface of the maritime lightering device; s4, combining the fuzzy controller with PID control to form a fuzzy adaptive PID control structure; and S5, forming a mixed architecture of an inverse solution feedforward channel and a layered terminal sliding mode feedback channel. According to the control method, the adaptive capacity is excellent, the fuzzy controller has the online self-adjusting capacity, the control strategy can be automatically adjusted according to different sea conditions, load changes and ship characteristics, the fuzzy controller and PID control are combined, a fuzzy adaptive PID control structure is formed, and intelligent control according to ship conditions and intelligent control according to sea conditions are achieved.

The invention discloses a superhelix global fast terminal sliding mode coordination ESP control method for improving red mouth blue magpie, and the method comprises the steps: building a vehicle dynamics model, employing a superhelix algorithm to suppress a chattering phenomenon, introducing a global fast terminal item to improve the convergence speed, and optimizing a sliding mode controller, according to the phase plane stability criterion, the control weights of the yaw velocity and the side slip angle are dynamically coordinated; optimizing the sliding mode controller by using a Red-beak-Blue-Tapie optimization algorithm according to a factor that the sliding mode controller is greatly influenced by inherent parameters of the sliding mode controller; improving a red-beak blue-magpie optimization algorithm to obtain an improved red-beak blue-magpie optimization algorithm, and calculating the fitness of the red-beak blue-magpie; according to an improved Red-beak-Blue-Tapie optimization algorithm, the optimal fitness is selected after iterative processing, all inherent parameters in a sliding mode controller are given to corresponding coordinate values, and the inherent parameters are applied to a constructed vehicle dynamics model, so that the dynamic stability and the anti-jamming capability of an automobile under the complex working condition are improved.

The application belongs to the technical field of laser radar scanning control, and discloses a MEMS galvanometer scanning method and system based on integral terminal sliding mode control. The method constructs an integral terminal sliding surface and introduces a minimum operator reaching law, so that the system state can converge to the sliding surface within a limited step, and the tracking error reaches a preset bandwidth within a limited step. Even under large-angle and high-speed scanning conditions, high-precision trajectory tracking can still be achieved, and there is no obvious distortion on the edge. In addition, the method estimates and compensates external disturbances in real time through an interference observer to reduce the gain required by the switching term in the sliding mode control. The interference observer estimates and dynamically compensates the sudden disturbance and the periodic disturbance online, thereby maintaining small steady-state error and phase stability. Under complex scenes such as compound disturbance, the control method can significantly improve the scanning accuracy and stability of the MEMS galvanometer.

The application discloses a method and system for suppressing subsynchronous resonance of a doubly-fed fan system based on thermal mass energy storage, establishes a nonlinear disturbance observer and a non-singular fast terminal sliding manifold observer based on a state space model of a thermal mass energy storage converter; when it is determined that the subsynchronous oscillation of the doubly-fed fan system occurs, the input voltage and the output current of the thermal mass energy storage converter are collected in real time, the estimated mismatch disturbance vector output by the nonlinear disturbance observer and the sliding manifold output by the non-singular fast terminal sliding manifold observer are used as the input quantities of a fast terminal sliding mode controller, the fast terminal sliding mode controller adopts a two-stage voltage approach law to output the regulating quantity of the input voltage of the thermal mass energy storage converter, and the thermal mass energy storage converter regulates the input voltage according to the regulating quantity to suppress the subsynchronous oscillation of the system. The application utilizes the current support capability of the thermal mass energy storage to provide necessary current support when the system fails, thereby effectively suppressing the subsynchronous oscillation of the doubly-fed induction generator system and improving the strength of the power grid.

The invention discloses a recursive nonsingular fast terminal sliding-mode active-disturbance-rejection control method for a permanent magnet synchronous motor based on a superspiral sliding-mode observer, and the method specifically comprises the following steps: 1, building a voltage equation of a surface-mounted PMSM in an alpha-beta static coordinate system, and building a mathematical model of the surface-mounted PMSM in a d-q rotating coordinate system through coordinate transformation; 2, designing a fractional order linear super-spiral sliding mode observer to obtain an observation value of the electrical angular velocity of the PMSM; 3, designing a recursive nonsingular fast terminal sliding mode controller; and step 4, making a difference between the mechanical angular velocity given value omega ref and the mechanical angular velocity observed value, and obtaining a control signal of a PMSM current loop through a recursive nonsingular fast terminal sliding mode controller according to the obtained error. By adopting the recursive nonsingular fast terminal sliding mode, global fast convergence of the speed tracking error can be ensured, the anti-interference capability of the system is improved, and buffeting is reduced.