10 results about "Repetitive control" patented technology

This application provides a control method, system, and electronic device for a PWM rectifier. The control method includes: determining the actual current of the PWM rectifier and determining a current error based on the actual current and a reference current; obtaining a first control parameter based on the current error using a preset algorithm; determining an error compensation value based on the current error using a repetitive controller, and compensating the first control parameter with the error compensation value to obtain a second control parameter; determining the fundamental frequency of the modulation wave based on the second control parameter, and obtaining a control signal based on the fundamental frequency of the modulation wave using a discontinuous pulse width modulation (DPWM) method to control the PWM rectifier. This application introduces a repetitive controller into the discontinuous pulse width modulation (DPWM) method, which improves the problem of large current harmonics caused by periodic errors due to periodic entry into clamping state in the DPWM modulation method, thereby improving control accuracy.

This invention relates to a model-free predictive repetitive control method and system for a dual-subspace virtual vector dual-three-phase permanent magnet synchronous motor. Based on the acquired operating parameters, the motor's vectors are decomposed into mutually orthogonal fundamental and harmonic subspaces, and independent hyperlocal models are constructed in both subspaces. A linear extended state observer is constructed in the fundamental subspace, and a repetitive extended state observer based on repetitive control is constructed in the harmonic subspace. Independent virtual voltage vector sets and decoupled virtual voltage vector sets are synthesized in the two subspaces, respectively. Reference voltage vectors for the two subspaces are calculated, and the optimal virtual voltage vector and optimal decoupled virtual voltage vector are selected. The optimal duty cycle is calculated for each subspace, and control signals are synthesized and applied to each arm of the inverter to drive the dual-three-phase permanent magnet synchronous motor. This invention achieves model-free control in a dual-subspace manner, and the control algorithm for the motor system's model parameters exhibits better robustness in the event of parameter mismatch.

The application relates to the technical field of brushless direct-current motors, in particular to an optimization control method for a permanent magnet brushless direct-current motor servo system, which comprises the following steps: S1.1: obtaining an equivalent system basic model of the permanent magnet brushless direct-current motor servo system; S1.2: improving the equivalent system basic model of the permanent magnet brushless direct-current motor servo system, and establishing a compound repetitive control law; and S1.3: optimizing control of the parameters of the equivalent system basic model of the permanent magnet brushless direct-current motor servo system. The application proposes a repetitive control system parameter optimization method based on an improved disturbance estimator compensation, establishes an optimization control model of system parameters based on the stability of the system, realizes synchronous optimization design of the parameters of a system repetitive controller, an improved disturbance estimator and a feedback controller, and makes the system simultaneously have satisfactory non-periodic disturbance suppression performance and periodic signal tracking performance.

The present invention aims at obtaining an optimal solution of an optimization problem at high speed and efficiently with a simple optimization algorithm. The solution search system is provided with: a plurality of data generating units (11-1 / ... / 11-i); a variation setting unit (16) that supplies a variation probability to the data generating units and sets the occurrence frequency of data generated by the data generating units to be non-uniform so that the occurrence frequency of a specific variable and the occurrence frequency of other variables form different values; a plurality of data converting units (12-1 / ... / 12-i) that read the data generated by the data generating units and convert them into information; an output adjustment unit (14) that transmits an output adjustment signal, or an output adjustment signal and a value of the variation probability, to the data generating units; and a feedback control unit (13) that repeatedly controls the action of transmitting the output adjustment signal, or the output adjustment signal and the value of the variation probability, to the data generating units when an optimal solution is not obtained.

The application provides a three-level inverter multi-rate control method, for any control axis of alpha beta 0: a voltage target value is subtracted from an actual value to obtain a voltage deviation, and a subscript is a control axis code; a repetitive controller is used as an input quantity, and an output result obtained is added to obtain; a state feedback controller is based on phase currents of alpha beta 0 and a control signal at a previous moment to output a control signal, and finally, the inverter is controlled to operate via 3D-SVPWM. The three-level inverter multi-rate control method can improve the dynamic performance and phase characteristics of the system by introducing the state feedback controller under the multi-rate control framework, configuring the closed-loop poles of the inverter discrete model, and thereby improving the stability of the system under the condition of downsampling.

The application discloses a permanent magnet synchronous motor active disturbance rejection current control method and device based on pole optimization. The prior art compensates and suppresses the periodic disturbance and constant disturbance existing simultaneously in the current control process of the permanent magnet synchronous motor by constructing a proportional-integral-repeated extended state observer. The use of the repeated control term introduces the closed-loop pole near the unit circle into the system, which leads to the decrease of the system stability margin, and the limited parameter adjustment range limits the disturbance suppression effect. Therefore, the application introduces a pole optimization link after the repeated control term to form an optimized extended state observer. The application reconstructs the closed-loop pole structure, eliminates the closed-loop pole near the unit circle edge introduced by the repeated control term, makes the closed-loop pole of the system determined by the proportional-integral link only, and thus expands the parameter adjustment range of the repeated control term under the premise of ensuring the system stability margin, and improves the periodic disturbance suppression capability.

The application discloses a method for improving frequency accuracy of repetitive control, which comprises a repetitive control module, and the repetitive control module comprises a decimal delay module and utilizes Lagrange interpolation method to realize the decimal delay in a digital domain, so as to improve tracking accuracy of repetitive control on a periodic waveform with an arbitrary frequency. The decimal delay module is realized by an integer delay unit and a Lagrange interpolation filter. The decimal delay is adopted to replace the integer delay, and the decimal delay is realized in the digital domain with high accuracy by utilizing the Lagrange interpolation method, so that the tracking accuracy of repetitive control on the periodic waveform with the arbitrary frequency is significantly improved.

The present application relates to a kind of high-speed motor harmonic suppression system based on virtual even fractional order repetitive controller, the definition of virtual fundamental frequency is proposed, and even harmonic repetitive controller is designed, only the control of even harmonic of virtual fundamental frequency can improve control frequency, enhance dynamic performance;Fractional order delay link based on second-order Lagrange interpolation is used, the decimal part of delay coefficient is fitted, the deviation of system resonance frequency and actual harmonic frequency is reduced, and the accuracy of harmonic suppression is improved;Secondly, low-pass filter with linear phase is used, and low-pass filter is removed from the inner mode of repetitive control, the phase of lag can be accurately compensated, and the tracking error of current harmonic in high frequency band is reduced.The present application can speed up the dynamic response of harmonic suppression, improve the accuracy of harmonic suppression and enhance the robustness of system, so as to effectively reduce motor loss.The system can not only be used for conventional speed motor, but also be more suitable for high-speed and super-speed motor harmonic suppression.

The application discloses a composite intelligent control method and system for an active power filter, through the synergistic effect of multiple source control signals, the tracking and compensation accuracy of harmonic and reactive current generated by a nonlinear load is significantly improved, the MPC weight is dynamically corrected in combination with a neural network, the change of power grid impedance, model mismatch and external disturbance can be effectively responded, a repetitive controller is introduced, memory and feedforward compensation are specially carried out on periodic harmonic error, the steady-state performance is improved, the MPC provides optimal switch selection under a limited control set, and millisecond-level response is realized.