16 results about "Zero-order hold" patented technology

The invention relates to a bridge crane game model-free optimal control method based on event triggering, and the method comprises the steps: collecting a state vector of a bridge crane in real time, and building a nonlinear multi-player system model of the bridge crane; estimating an unknown dynamic function and an input gain matrix on line in the input identifier neural network; according to an event triggering mechanism, whether triggering is conducted or not is judged based on the error between the current state vector and the state vector of the recently-triggered sampling; if so, triggering a dynamic updating instruction; under a non-zero sum game framework, obtaining an optimal value function gradient based on an estimation result and a current state vector through a self-adaptive evaluator network, and generating an event triggering optimal control law of each player based on a sampled state vector; and the event triggering optimal control law is processed by a zero-order retainer and then is output as a physical driving signal to control the operation of the bridge crane. Compared with the prior art, the method has the advantages of high applicability, high disturbance resistance, high accuracy and the like.

The invention provides a wind power integration system small disturbance modeling and stability analysis method considering control delay, and the method comprises the steps: introducing a sampling delay link, a zero-order holding link and a switch delay link in a small disturbance linearization modeling process, carrying out the linearization processing through employing a first-order inertia link, and building a unified state space model; respectively constructing control delay mathematical models of the direct-driven fan and the double-fed fan, and analyzing and identifying the influence of the control delay on the oscillation mode and stability of the system through characteristic values and impedance; and finally, performing time domain simulation in the simulation platform, and comparing a calculation result with a simulation result to verify the accuracy of the model. The method can accurately reflect the small disturbance characteristics of the wind power grid-connected system in the sub-synchronous frequency band and the super-synchronous frequency band, provides a theoretical basis for optimization of control parameters of a wind turbine generator and evaluation of grid-connected stability, and solves the technical problem that the influence of control delay is generally ignored in modeling of an existing wind power grid-connected system.

The invention relates to the field of sensor data calibration, in particular to an intelligent sensor data calibration method for sensing the state of an electric reactor, which comprises the following steps of: mapping power supply voltage into three engineering states of stability, drifting and distortion based on the physical characteristics of an analog device, and introducing asymmetric hysteresis comparison logic to prevent the state oscillation of a critical point. In the stable state, the system executes baseline clamping and dead zone control to filter background noise; in a drift state, a look-up table is preset based on a real-time voltage index, and sensor gain attenuation is compensated by using a fixed-point displacement algorithm; and in a distorted state, starting a logic fusing mechanism to shield invalid signals. In addition, timing alignment of low-speed power data and high-speed partial discharge signals is realized through a zero-order holding strategy. The problems of signal distortion and false alarm caused by power supply voltage fluctuation are effectively solved, and the robustness and monitoring accuracy of the sensor in a complex electromagnetic environment are remarkably improved.

The invention discloses a grid-connected inverter continuous set model prediction control method based on neurodynamics optimization. The method comprises the following steps: establishing a continuous time state space model of an LCL type grid-connected inverter in a static coordinate system; performing full-order discretization processing on the continuous time state space model through a zero-order retention method to obtain a discrete state space model; according to the discrete state space model, constructing a standard quadratic form cost function about an unknown control voltage increment sequence of the LCL type grid-connected inverter; solving the standard quadratic form cost function to obtain an unconstrained optimal control increment sequence; and according to the unconstrained optimal control increment sequence, constructing a nonlinear programming model of multiple heterogeneous constraints, and solving a nonlinear programming problem through a constructed neurodynamics optimizer so as to realize continuous set model prediction control of the LCL type grid-connected inverter. According to the method, the problem that the dynamic response speed and the control precision of the inverter are insufficient in the existing method is solved.

This invention relates to a teleoperated robot control method based on event triggering and finite-time control, solving the problem of poor stability of teleoperated robots with asymmetric variable time delay, achieving finite-time position tracking convergence, and saving network communication resources. The method includes: sending the master-end position signal and the slave-end position signal via a zero-order hold to the master-end finite-time controller to calculate the control torque, which is then sent to the master-end robot to control its movement; sending the master-end position signal to the master-end event triggering decision-maker, which determines whether to use the communication network to transmit the current master-end position information based on the master-end event triggering strategy; sending the slave-end position signal and the master-end position signal via a zero-order hold to the slave-end finite-time controller to calculate the control torque, which is then sent to the slave-end robot to control its movement; and sending the slave-end robot position signal to the slave-end event triggering decision-maker, which determines whether to use the communication network to transmit the current slave-end position information based on the slave-end event triggering strategy.

The application discloses a ship resilience reinforcement course keeping control method under network attack, comprising the following steps: establishing a responsive nonlinear Nomoto model as a ship motion mathematical model to obtain a simplified transfer function; constructing a ship course robust controller according to the simplified transfer function based on a second-order closed-loop gain shaping algorithm; obtaining a ship course error under consideration of ship network attack to perform nonlinear modification on the control input of the ship course robust controller; obtaining the control input of the ship course robust controller after nonlinear modification, and performing equivalent transformation model of input signal feedback; optimizing the control output of the ship course robust controller according to the equivalent transformation model by using a zero-order holder to obtain optimized rudder angle control output; and obtaining a final ship navigation course according to the optimized rudder angle control output in consideration of marine environmental interference. The technical problem that the traditional ship control strategy cannot resist network attack to guarantee the ship course and collision avoidance control functions is solved.

The application provides a kind of wind power grid-connected system small disturbance modeling and stability analysis method considering control delay, the method introduces sampling delay, zero-order hold and switch delay link in small disturbance linearization modeling process, linearization is handled using first-order inertia link, and a unified state space model is established;Direct drive wind turbine and double-fed wind turbine control delay mathematical model is constructed respectively, the influence of control delay on system oscillation mode and stability is identified through eigenvalue and impedance analysis;Finally, time domain simulation is carried out in simulation platform, and the accuracy of the model is verified by comparing the calculation results and simulation results. The method can accurately reflect the small disturbance characteristics of wind power grid-connected system in sub-synchronous and super-synchronous frequency band, provide a theoretical basis for wind turbine control parameter optimization and grid-connected stability evaluation, and solve the technical problem that the influence of control delay is generally ignored in existing wind power grid-connected system modeling.

The application discloses a zero intermediate frequency satellite communication signal processing method and system based on an embedded microcontroller, and the method comprises the following steps: encoding and framing original data, generating I / Q digital baseband waveforms through QPSK mapping, upsampling and shaping filtering, and converting analog signals through a double-channel DAC. In view of Sinc fading and adjacent channel leakage caused by the zero-order holding effect of the DAC, two-stage cascade suppression is adopted: the first stage of attenuation is performed in the digital domain; the second stage of physical filtering is performed in the analog domain between the DAC and the mixer by using the stop band notch characteristic of the symmetrical active differential low-pass filter circuit, and the independent direct current bias adjustment is used for IQ balance adjustment to eliminate the carrier leakage. Finally, the mixer is used for one-step up-conversion, and a power amplifier is used for emission. The method does not need closed-loop digital IQ correction, significantly reduces resource consumption, and improves the adjacent channel power ratio and radio frequency quality.

The invention discloses a finite field trace-based multi-level pseudo-random disturbance signal generation method and system. The method comprises the steps of constructing an extension field according to a target level number and an expected period; generating an extension field element sequence in the extension field according to the selected non-zero primitives and coefficients, wherein the extension field element sequence is a non-zero extension field element sequence; domain trace mapping is applied to the extended domain element sequence, so that the dimension of the extended domain element sequence is reduced to obtain a base domain symbol sequence; and converting the base domain symbol sequence into a symmetric multi-level symbol sequence according to a predetermined mapping rule, and expanding the symmetric multi-level symbol sequence into a continuous time disturbance signal through zero order keeping, namely a multi-level pseudo-random disturbance signal. According to the method, the level number and the signal period of the disturbance signals can be adjusted according to needs, the disturbance signals with controllable spectral characteristics and wide frequency band coverage are generated, the method has the advantages of being uniform in spectral line distribution, excellent in correlation, simple in hardware implementation and the like, the frequency domain resolution of impedance estimation can be improved conveniently, and injection transient stress is reduced.

The invention provides an active-disturbance-rejection control method for an electromagnetic bearing two-level digital switch power amplifier embedded with model information so as to improve the response speed and precision of a current inner ring. Firstly, based on the Fourier series theory and coil current characteristics, a mathematical model suitable for controller design is established. Secondly, performing modelable disturbance term feed-forward compensation on a direct current component in the model; parameter perturbation and an unmodeled part are used as unknown disturbance terms, and an extended state observer is used for real-time estimation. Meanwhile, known information such as a current item is embedded into an observer, and a feedback control law is designed to compensate various items in real time. And finally, discretizing a controller by using a zero-order retainer and a current observer, and implementing on a DSP (Digital Signal Processor) digital control platform. The control performance is excellent, compared with PI and active-disturbance-rejection control, the current response is faster, the precision is higher, and the method is of great significance to stable operation of the magnetic suspension rotor.

The application discloses a kind of GCRA- LightGBM-based ICPS comprehensive safety control system and method under D-ADETC, comprising: sampler, equal period sampling is carried out to sensor measurement output data;Self-adapting discrete event trigger A, transmission screening is carried out to sampling value, and the data meeting data transmission condition A is transmitted through sensing side communication network;Data reconfiguration restorer A, repair the system output data of sensing side suffered FDI attack, and control quantity is obtained after the repaired data is acted on by robust observer and controller;Self-adapting discrete event trigger B, transmission screening is carried out to control quantity, and the control quantity meeting data transmission condition B is transmitted through execution side communication network;Data reconfiguration restorer B, repair the control data of execution side suffered FDI attack, utilize zero-order hold to keep the control quantity after repair, and be acted on by actuator to controlled object, complete the comprehensive safety control of ICPS.

The invention discloses a BO-BiCGStab-based TI-DAC amplitude-frequency response pre-equalization method and system, belongs to the technical field of digital signal processing, and solves the problems that the TI-DAC is influenced by factors such as zero-order roll-off keeping characteristic, inconsistent sub-channel amplitude-frequency response and non-ideal analog link, so that the amplitude-frequency response of an output signal passband is uneven, and the signal quality is reduced. Firstly, TI-DAC passband amplitude-frequency response is modeled, influence factors of the TI-DAC passband amplitude-frequency response are analyzed, and precoder frequency response is converted into a linear equation set form in a cosine matrix form. And then a stable biconjugate gradient algorithm is adopted to iteratively solve the linear equation set, finally, a frequency weighting mechanism is introduced in a modeling stage, and Bayesian optimization is utilized to perform adaptive configuration on the frequency weight to obtain an optimal coefficient of the pre-equalizer. The method is suitable for scenes such as high-speed broadband communication.

The invention relates to the technical field of automatic control, and discloses a sliding mode control method and system for a dividing wall heat exchange space-time two-dimensional system, and the method comprises the steps: 1, constructing a two-dimensional system model as a controlled object; 2, collecting a state signal of the controlled object; constructing a dynamic event triggering mechanism to determine a transmission sequence of the state signal; 3, performing nonsingular transformation on the space-time two-dimensional system model, and decomposing the space-time two-dimensional system model into two low-order subsystems; 4, constructing a linear sliding mode surface based on the decomposed low-order subsystem; step 5, constructing a sliding mode controller based on the dynamic event triggering mechanism; and 6, performing zero-order holding on a control signal output by the sliding mode controller, and then acting the control signal on the space-time two-dimensional system model based on the dividing wall heat exchange temperature field to realize closed-loop control. According to the application, the temperature control data transmission frequency between the sensor and the controller can be more intelligently reduced, so that the network bandwidth and communication resources are effectively saved.

The embodiment of the application discloses a current inner loop control parameter identification method of a new energy grid-connected converter, comprising the following steps: determining a target transfer function according to a first transfer function of a zero-order holder, a second transfer function of a PWM controller, a third transfer function of a current inner loop control link and a fourth transfer function of a main circuit control link; then replacing the third transfer function and the fourth transfer function with the target transfer function and removing a proportional integral item of a fifth transfer function of a voltage outer loop control link; finally, performing step disturbance on a q-axis component reactive power reference value and a d-axis component DC voltage reference value of the voltage outer loop control link respectively, obtaining a first response curve and a second response curve of current feedback values of q-axis components and d-axis components of the current inner loop control link respectively, and determining control parameters of the q-axis components and the d-axis components of the current inner loop control link respectively; the method can effectively solve the technical problems existing in the prior art.

The present application relates to the field of sensor data calibration, and particularly relates to a kind of intelligent sensor data calibration method for reactor state perception, power voltage is mapped to three engineering states of stability, drift and distortion based on analog device physical characteristics, and non-symmetrical hysteresis comparison logic is introduced to prevent critical point state oscillation.In stable state, baseline clamping and dead zone control are executed to filter background noise;In drift state, based on real-time voltage index preset lookup table, sensor gain attenuation is compensated using fixed-point displacement algorithm;In distortion state, start logic fuse mechanism to shield invalid signals.In addition, through zero-order hold strategy, low-speed power data and high-speed partial discharge signal are time-aligned.The present application effectively solves the problem of signal distortion and false alarm caused by power supply voltage fluctuation, significantly improves the robustness and monitoring accuracy of sensor in complex electromagnetic environment.

The invention provides a motor three-phase current sampling method and system, and the method comprises the steps: carrying out the N times of sampling of the motor three-phase current in a control period, and calculating an arithmetic mean value, so as to obtain an initial average current, thereby effectively smoothing the random noise, and improving the signal-to-noise ratio of a signal. And furthermore, aiming at systematic amplitude attenuation which is introduced by a zero-order retainer in the system and is related to frequency, a compensation coefficient is determined based on amplitude-frequency characteristics of the systematic amplitude attenuation, the coefficient is utilized to compensate the initial average current so as to offset an inherent error, and finally a final sampling result capable of accurately restoring the real amplitude of the current is obtained. According to the method, multi-sampling and zero-order maintenance compensation are combined, so that the inherent deviation of a sampling system is corrected from the source, the current sampling precision is remarkably improved, and a solid foundation is laid for high-performance vector control of the motor.