60results about How to "Solve chattering problems" patented technology

The invention pertains to the technical field permanent magnet motors, and relates to a permanent magnet motor sliding mode control strategy. The permanent magnet motor is controlled by adopting double-closed speed current. The permanent magnet motor sliding mode control strategy is characterized in that a sliding mode speed controller and an extended sliding mode observer are adopted in the control strategy, the sliding mode speed controller adopts an exponential approach law containing the speed error and the sliding mode surface information, the deviation between a given rotating speed and a feedback rotating speed is taken as the input quantity, and a q-axis current given value is outputted through the sliding mode control quantity; the extended sliding mode observer is used to estimate the rotor position, the rotating speed and the load torque on a real-time basis, the rotating speed and the rotor position are used to provide the information of speed closed-loop control and coordinate transformation, and the load torque is compensated to the sliding mode speed controller, so that the high-accuracy vector control of the permanent magnet motor can be realized. The control strategy of the invention can be used to make the system fast track a given speed in the dynamic state, reduce the speed overshoot and the current fluctuation, and improve the disturbance resistance performance of the system.

The invention relates to a model reference self-adaptive sliding mode control method for a vertical takeoff and landing reusable launch vehicle, and belongs to the technical field of aircraft control.A self-adaptive sliding mode reaching law with fixed convergence characteristics and a second-order fixed-time convergence extension state observer are introduced into the design of a model referenceself-adaptive sliding mode controller, the capability of a system for suppressing complex external interference is improved accordingly, and meanwhile the precision and tracking speed of model tracking are increased.

A reconfigurable mechanical arm decentralized control system and control method adopting position measuring belong to the field of robot control systems and control algorithms, and aim to solve the problems existing traditional reconfigurable mechanical arm control systems and methods thereof. The control method comprises the steps of initializing a system, detecting a reading of an incremental encoder to obtain position measuring information, and establishing a non-linear speed observer based on the information; according to the established non-linear speed observer, establishing a disturbance observation model; adopting an observation value obtaining a joint speed and a joint torque to establish a reconfigurable mechanical arm system dynamics model; by a given joint speed observer, a torque observer, expected dynamics information and the system dynamics model, adopting dynamics information of local joints to design a decentralized controller, compensating the modeling errors containing model determining items and friction and coupling items among joints, and inhibiting buffeting of the controller and enabling a mechanical arm joint to precisely trace an expected track.

The invention discloses a self-adaption sliding mode control method for speed regulation of a variable-load permanent magnet synchronous motor. According to the method, on the conditions that a speed reference value of the permanent magnet synchronous motor is given and a load changes, second-order finite time disturbance observers are designed respectively for step interference and successive interference, load changes are estimated and compensated for, an absolute value fractional order sliding mode surface is designed, an improved power reaching law method is provided, and a continuous sliding mode controller is designed. A self-adaption sliding mode controller composed of the second-order finite time disturbance observers and the continuous sliding mode controller is used for conducting speed regulation on the permanent magnet synchronous motor to enable the motor to be still capable of running at reference speed after the load changes, and the influences brought by load changes to the rotation speed of the motor are greatly reduced. The self-adaption sliding mode control method inherits good robustness of sliding mode control; meanwhile, the expanded second-order finite time disturbance observers are used for observing step signals, rotation speed fluctuation on the condition that the load changes is reduced, and the driving capacity of the permanent magnet synchronous motor is effectively improved.

The invention relates to a maglev train system control method based on integral sliding mode control of a double power reaching law (DPRL-I-SMC), and especially relates to a maglev train system control method based on integral sliding mode control of an improved double power reaching law. A sliding mode controller is designed by combining the double power reaching law and the exponential reachinglaw and using a saturation function and an integral function. The improved DPRL-I-SMC method is superior to the traditional sliding mode control (SMC) and power reaching law-integral sliding mode control (PRL-I-SMC) methods in all aspects, can effectively eliminate the chattering of the system, reduce overshoot, accelerate convergence and overcome nonlinear factors to make a nonlinear system stably suspended, and shows excellent dynamic performance and anti-jamming performance.

The invention discloses a one-way sliding-mode control method of a single rotor wing unmanned aerial vehicle. A one-way sliding-mode controller of each loop is designed by utilizing of affine nonlinear equations of four control loops including an angular rate loop, an eulerian angle loop, a speed loop and a position loop in a control system of the aerial vehicle. The control on the single rotor wing unmanned aerial vehicle is achieved by utilizing of the four one-way sliding-mode controllers. According to the one-way sliding-mode control method, the problem of buffeting in the sliding-mode control method is solved on the basis that the reaching law of the sliding-mode in the controllers is zero if and only if the system state is in an original point, and the controllers are good in robustness and controlling performance.

The invention discloses a chattering-free sliding mode control method for a buck converter, and belongs to the field of power electronic converters. The invention designs the chattering-free sliding mode control method for the buck converter by a second-order sliding mode control theory on the basis of an average state model of the buck converter. By a constant-frequency PWM mode, on or off is controlled by changing the duty ratio of a switching device, so that target voltage output of the buck converter is achieved. Meanwhile, the whole scheme of a buck converter system under the action of the control method is achieved on the basis of a LabVIEW platform. The widely existed chattering problem in traditional sliding mode control and the problems that a buck converter controlled by a linear PID method is low in response speed, low in voltage output quality, poor in anti-disturbance capability and the like are solved; and the control method overcomes disturbance influences of a load resistance, a DC input voltage and the like and improves the performance of an output voltage by the advantages of strong robustness, high steady accuracy and the like.

The invention discloses a discrete two-cycle repeating control method based on a hyperbolic secant attraction law. A reference signal formed via superposition of two different cyclic symmetries is given; according to cyclic symmetry characteristics of interference signals of different cycles in a time domain, ideal error dynamics are respectively produced based on the hyperbolic secant attractionlaw; according to the ideal error dynamics, an e/v signal conversion module is established, output signals are used for correction of sub-repetitive controllers, and a discrete double cycle repetitivecontroller is formed after the sub-repetitive controllers are connected in parallel; output signals of the discrete double cycle repetitive controller are calculated as input to a servo object, and aservo system is enabled to change along with reference signals. Specific controller parameter setting work can be performed according to amplitudes of different periodic interference and indexes indicating system tracking error convergence performance and steady state performance; a method for calculating a monotonous decreasing region indicating the tracking error convergence performance and thesteady state performance, an absolute attraction layer and a steady state error band boundary is provided. The invention provides a discrete double cycle repetitive controller based on the hyperbolicsecant attraction law; the controller is advantaged by time domain design, fast suppression of multi-cycle interference, good dynamic quality, reduced memory occupancy and high control precision.

The invention discloses an integrated underwater thruster driving system and a control method, which realizes the integrated underwater thruster sensorless control. A linear back EMF sliding mode observer based on fuzzy switching gain adjustment is provided, The observer adopts a smooth hyperbolic tangent function and fuzzy rules to realize change of a gain value and reduce the chattering of the system, so that the control system can obtain smooth back EMF estimates without adding a low pass filter and a phase compensation module, thus avoiding the phase lag of the back EMF estimates. The lineback EMF estimates are corresponded to three virtual Hall signals and six discrete commutation signals are obtained directly without the need of fixed phase shift circuit and calculation of phase shift angle. the invention realizes the integrated underwater thruster sensorless control by estimating the line back EMF of the brushless DC motor loaded in the underwater thruster,.

The invention relates to a speed sensorless control method for a permanent magnet synchronous motor (PMSM) based on an MRAC observer. The method is characterized by connecting an improved model reference adaptive observer module based on a super-helical sliding mode to a PMSM speed regulating system to detect the rotor position and the rotational speed of the motor; inputting the stator current idand iq in a two-phase rotating coordinate system and a voltage reference value ud and a voltage reference value uq output by two current loop PI controllers into the model reference adaptive observermodule based on the super-helical sliding mode; and obtaining, by the model reference adaptive observer module based on a super-helical sliding mode, an estimated motor speed [ometa]e and a rotor angular position [theta] for speed feedback and PAR transformation and IPARK transformation after processing the data. The method replaces a PI link in a traditional model reference adaptive observer bya super-spiral sliding mode algorithm, so that the PMSM speed regulating system has good robustness and anti-interference performance, and improves the estimated accuracy of the motor speed and the rotor position.

The invention discloses a servosystem position tracking control method based on hybrid sliding mode control. The method comprises establishment of a permanent magnet synchronous motor system with outer disturbance, and designing of a sliding mode disturbance observer based on a motor model, and a second order supercoiled sliding mode control algorithm. A specific method comprises the following steps: firstly, considering uncertainty of motor parameters and load torque as lumped disturbance, designing an adaptive extension sliding mode disturbance observer to estimate uncertainty interference of the motor parameters and the load torque; secondly, presenting a new terminal sliding mode function, and designing a second order supercoiled controller based on the adaptive extension sliding modedisturbance observer, wherein a nonlinear switching term is introduced to reduce buffeting of the system. Convergence of a terminal sliding mode curved surface and stability of the controller are proved further. The method provided by the invention can effectively solve stable control of servosystem position tracking of a system model under outside disturbance.

The invention discloses a method of controlling a three-phase PWM (Pulse Width Modulation) inverter based on a second-order sliding mode and a disturbance observer. The method is applicable to the high-performance control of the three-phase AC (alternating current) inverter and comprises the steps: firstly, decoupling a three-phase AC inverter system into two single-phase second-order sub-systems in the use of 3/2 coordinate transformation; secondly, designing the two second-order sub-systems on this basis and designing the disturbance observer to observe matched and non-matched disturbances under the condition of considering the load transformation of the system; and thirdly, designing the compound control method of the second-order sliding mode and the disturbance controller on the basis of acquiring disturbance estimation values so as to improve the anti-load-disturbance ability of the system. The method is simple to realize and has less regulation of parameters; the voltage output harmonic waves of the three-phase AC inverter system can be reduced effectively, so that the purpose of improving stability precision of the AC inverter system is achieved and the application of the high-performance AC inverter system in the voltage output field is satisfied.

The invention provides a sliding mode control method and apparatus. The method comprises: a switching item of a control system is obtained; according to the switching item, a control quantity is determined and outputted, wherein a second derivative of the control quantity includes the switching item; and according to the control quantity, the control system is controlled. According to the method, because the switching item is included by the second derivative of the control quantity, the control quantity is a quadratic integral of the switching item and the changing rate of the control quantity is a once integral of the switching item; and the switching item becomes continuous after integration and thus the control quantity and the control quantity changing rate become continuous. Therefore, the sliding mode control method is suitable for control of the process without control quantity and derivative mutation; a defect that the traditional sliding mode control quantity and the derivative are not continuous can be overcome; and a problem that buffeting exists in sliding mode control under the circumstance that the control system is in a non-linear mode and the model is not accurate can be solved.

The invention provides a permanent magnet synchronous motor chaos suppression method and system based on equivalent input disturbance. The method comprises the following steps: firstly, establishing asystem model of a permanent magnet synchronous motor; secondly, adding input to obtain a system chaos model of the permanent magnet synchronous motor, suppressing the system interference by adoptinga controller based on an equivalent input interference method, and adopting a PI controller to control the system current and the rotating speed; and finally, obtaining the closed-loop system input based on the equivalent input interference. The permanent magnet synchronous motor chaos suppression system based on the equivalent input disturbance comprises different modules to suppress the system interference according to the chaos suppression requirements of the permanent magnet synchronous motors. The permanent magnet synchronous motor chaos suppression method and the system based on the equivalent input disturbance provided by the invention have the following beneficial effects: the calculation amount is small and the real-time performance is high; the buffeting problem of the system isavoided, and the application range is improved; the parameter design is simple, and practical application is facilitated; and the system is low in conservation, high in robustness and higher in control precision.

The invention discloses an adaptive variable impedance control method for a clamping mechanism of a fruit sorting parallel robot. According to the method, an impedance controller outer loop and a position controller inner loop are used to form a cascade control structure, the deviation between the expected clamping force and the acquired actual contact force is taken as the input of an outer ringforce impedance controller, the outer ring force impedance controller generates the correction amount of the inner ring position reference track, and the clamping force control is realized through theadaptive variable impedance control of the clamping mechanism of the fruit sorting parallel robot. An adaptive variable impedance control algorithm of the clamping mechanism of the fruit sorting parallel robot has the adaptability to the movement speed and load change of the clamping mechanism, and lossless clamping of the fruit can be achieved through the clamping mechanism of the fruit sortingparallel robot.

The invention discloses a stepping motor anti-interference system based on TS fuzzy sliding mode control and belongs to the technical field of power systems. The method of the system comprises the following steps: 1, setting a model of a two-phase hybrid stepping motor under natural coordinates; 2, decoupling the stepping motor model under the natural coordinates: carrying out d-q synchronous rotation coordinate axis transformation on the model; 3, establishing a T-S fuzzy model of the two-phase hybrid stepping motor; 4, performing transformation and variable decomposition on the T-S fuzzy model, selecting a proper sliding mode surface, and establishing a proper sliding mode function to determine a sliding model; and 5, designing a sliding mode control law. On the basis of fuzzy control, sliding mode control is combined to improve the robustness of the control system and ensure the operation accuracy of the stepping motor.

The invention relates to a three-phase rectifier sliding-mode control method based on an extended state observer (ESO), comprising a three-phase rectifier main circuit in which a three-phase voltage is subjected to AC /DC conversion through a filter inductor L, a resistor r and a three-phase bridge rectifier and an external load is connected in parallel with a DC-side capacitor C and which comprises a controller for the on-off control of the three-phase bridge rectifier, wherein the outer loop of the controller is a voltage loop based on an ESO, and the inner loop of the controller is a powerloop using a super-twisting algorithm. The control method comprises the steps of: S1, establishing a three-phase rectifier circuit dynamic model; S2 designing the controller: a) designing the power loop by using the super-twisting algorithm, and b) designing the voltage loop based on the ESO. The control method applies the super-twisting algorithm and the ESO to the control of the three-phase rectifier, solves the system buffeting, and improves system robustness and stability.