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3D舞台威亚系统RUL预测与变采样率DMC-PID延寿方法研究
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作者 毛海杰 张晓瑞 +1 位作者 冯小林 蒋栋年 《控制理论与应用》 北大核心 2025年第12期2545-2556,共12页
针对3D舞台威亚系统因伺服电机退化导致的安全性问题,考虑已有退化模型精度不高、传统寿命定义保守、延寿效率低下等问题,本文提出了一种基于复合多阶段退化建模的系统级剩余寿命预测方法,并基于预测结果开展了自适应变采样率自主维护... 针对3D舞台威亚系统因伺服电机退化导致的安全性问题,考虑已有退化模型精度不高、传统寿命定义保守、延寿效率低下等问题,本文提出了一种基于复合多阶段退化建模的系统级剩余寿命预测方法,并基于预测结果开展了自适应变采样率自主维护策略研究.首先,从工程实际出发,构建了包含基础控制层、健康评估层及自主维护层的三层级自主维护框架;其次,考虑退化阶段的差异性与随机冲击的影响,建立了Wiener+Poisson复合多阶段退化模型,并采用期望最大化参数估计算法,将参数估计过程与累加和变点检测算法相融合,采用更适宜评价控制系统寿命的最后逃逸时间定义,求解得到复合多阶段退化模型下系统剩余寿命的解析解;最后,基于预测结果,提出了基于自适应变采样率的DMC-PID延寿控制策略,提高了维护效率和效果.仿真实验验证了所提方法的有效性. 展开更多
关键词 3D舞台威亚系统 剩余寿命预测 复合多阶段退化 最后逃逸时间 自主维护 dmc-pid延寿控制
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基于前馈DMC-PID的SCR脱硝系统串级预测控制
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作者 丛日学 刘宗奇 陈立军 《吉林电力》 2025年第1期5-10,30,共7页
针对选择性催化还原(Selective Catalytic Reduction,SCR)脱硝系统优化控制问题,利用粒子群算法进行全工况系统辨识;基于动态矩阵控制(Dynamic Matrix Control,DMC)理论提出了一种带前馈的全工况DMC-PID串级控制策略,并搭建前馈DMC-PID... 针对选择性催化还原(Selective Catalytic Reduction,SCR)脱硝系统优化控制问题,利用粒子群算法进行全工况系统辨识;基于动态矩阵控制(Dynamic Matrix Control,DMC)理论提出了一种带前馈的全工况DMC-PID串级控制策略,并搭建前馈DMC-PID控制框架。仿真结果显示,该方法超调更小,调节速度更快,优于其他控制,尤其在低工况下效果更为明显;同时在扰动实验中,也验证了该方法较强的抗干扰能力,可以实现SCR脱硝系统优化控制。 展开更多
关键词 SCR脱硝系统 前馈dmc-pid 全工况模型 串级预测控制
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A DDPG-based Path Following Control Strategy for Autonomous Vehicles by Integrated Imitation Learning and Feedforward Exploration
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作者 Qianjie Liu Peixiang Xiong +4 位作者 Qingyuan Zhu Wei Xiao Kejie Wang Guoliang Hu Gang Li 《Chinese Journal of Mechanical Engineering》 2025年第5期207-223,共17页
Autonomous driving technology is constantly developing to a higher level of complex scenes,and there is a growing demand for the utilization of end-to-end data-driven control.However,the end-to-end path tracking proce... Autonomous driving technology is constantly developing to a higher level of complex scenes,and there is a growing demand for the utilization of end-to-end data-driven control.However,the end-to-end path tracking process often encounters challenges in learning efficiency and generalization.To address this issue,this paper designs a deep deterministic policy gradient(DDPG)-based reinforcement learning strategy that integrates imitation learning and feedforward exploration in the path following process.In imitation learning,the path tracking control data generated by the model predictive control(MPC)method is used to train an end-to-end steering control model of a deep neural network.Another feedforward exploration behavior is predicted by road curvature and vehicle speed,and adds it and imitation learning to the DDPG reinforcement learning to obtain decision-making experience and action prediction behavior of the path tracking process.In the reinforcement learning process,imitation learning is used to update the pre-training parameters of the actor network,and a feedforward steering technique with random noise is adopted for strategy exploration.In the reward function,a hierarchical progressive reward form and a constrained objective reward function referring to MPC are designed,and the actor-critic network architecture is determined.Finally,the path tracking performance of the designed method is verified by comparing various training results,simulations,and HIL tests.The results show that the designed method can effectively utilize pre-training and feedforward prior experience to obtain optimal path tracking performance of an autonomous vehicle,and has better generalization ability than other methods.This study provides an efficient control scheme for improving the end-to-end control performance of autonomous vehicles. 展开更多
关键词 Autonomous vehicle Path following feedforward exploration Reinforcement learning
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Application of feedforward and recurrent neural networks for model-based control systems
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作者 Marek Krok Wojciech P.Hunek +2 位作者 Szymon Mielczarek Filip Buchwald Adam Kolender 《Control Theory and Technology》 2025年第1期91-104,共14页
In this paper,a new study concerning the usage of artificial neural networks in the control application is given.It is shown,that the data gathered during proper operation of a given control plant can be used in the l... In this paper,a new study concerning the usage of artificial neural networks in the control application is given.It is shown,that the data gathered during proper operation of a given control plant can be used in the learning process to fully embrace the control pattern.Interestingly,the instances driven by neural networks have the ability to outperform the original analytically driven scenarios.Three different control schemes,namely perfect,linear-quadratic,and generalized predictive controllers were used in the theoretical study.In addition,the nonlinear recurrent neural network-based generalized predictive controller with the radial basis function-originated predictor was obtained to exemplify the main results of the paper regarding the real-world application. 展开更多
关键词 Predictive control Linear-quadratic control Inverse problems feedforward network Recurrent neural network OPTIMIZATION
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Realizing high-speed target tracking by using multi-rate feedforward predictive control for the acquisition, tracking, and pointing system
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作者 Hang Li Gaoliang Peng +4 位作者 Xiaobiao Shan Mingyuan Zhao Wei Zhang Jinghan Wang Feng Cheng 《Defence Technology(防务技术)》 2025年第7期137-151,共15页
The acquisition,tracking,and pointing(ATP)system is widely used in target tracking,counter-UAV operations,and other related fields.As UAV technology develops,there is a growing demand to enhance the tracking capabilit... The acquisition,tracking,and pointing(ATP)system is widely used in target tracking,counter-UAV operations,and other related fields.As UAV technology develops,there is a growing demand to enhance the tracking capabilities of ATP systems.However,in practical applications,ATP systems face various design constraints and functional limitations,making it infeasible to indefinitely improve hardware performance to meet tracking requirements.As a result,tracking algorithms are required to execute increasingly complex tasks.This study introduces a multi-rate feedforward predictive controller to address issues such as low image feedback frequency and significant delays in ATP systems,which lead to tracking jitter,poor tracking performance,low precision,and target loss.At the same time,the pro-posed approach aims to improve the tracking capabilities of ATP systems for high-speed and highly maneuverable targets under conditions of low sampling feedback rates and high feedback delays.The method suggested is also characterized by its low order,fast response,and robustness to model parameter variations.In this study,an actual ATP system is built for target tracking test,and the proposed algorithm is fully validated in terms of simulation and actual system application verification.Results from both simulations and experiments demonstrate that the method effectively compensates for delays and low sampling rates.For targets with relative angular velocities ranging from 0 to 90°/s and angular accelerations between 0 and 470°/s^(2),the system improved tracking accuracy by 70.0%-89.9%at a sampling frequency of 50 Hz and a delay of 30 m s.Moreover,the compensation algorithm demonstrated consistent performance across actuators with varying characteristics,further confirming its robustness to model insensitivity.In summary,the proposed algorithm considerably enhances the tracking accuracy and capability of ATP systems for high-speed and highly maneuverable targets,reducing the probability of target loss from high speed.This approach offers a practical solution for future multi-target tracking across diverse operational scenarios. 展开更多
关键词 Multi-rate systems Predictive feedforward control Target tracking Laser weapon
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Extraction of fissile isotope antineutrino spectra using feedforward neural network
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作者 Jian Chen Jun Wang +1 位作者 Wei Wang Yue-Huan Wei 《Nuclear Science and Techniques》 2025年第10期13-23,共11页
The precise measurement of the antineutrino spectra produced by isotope fission in reactors is of great significance for studying neutrino oscillations,refining nuclear databases,and addressing the reactor antineutrin... The precise measurement of the antineutrino spectra produced by isotope fission in reactors is of great significance for studying neutrino oscillations,refining nuclear databases,and addressing the reactor antineutrino anomaly.In this paper,we report a method that utilizes a feedforward neural network(FNN)model to decompose the prompt energy spectrum observed in a short-baseline reactor neutrino experiment and extract the antineutrino spectra produced by the fission of major isotopes such as^(235)U,^(238)U,^(239)Pu,and^(241)Pu in the nuclear reactor.We present two training strategies for the model and compare them with the traditional X^(2) minimization method by applying them to the same set of pseudo-data corresponding to a total exposure of(2.9×5×1800)GW_(th)·tons·days.The results show that the FNN model not only converges faster and better during the fitting process but also achieves relative errors of less than 1%in the 2−8 MeV range in the extracted spectra,outperforming the X^(2) minimization method.The feasibility and superiority of this method were validated in the study. 展开更多
关键词 Reactor neutrinos Isotope antineutrino spectra feedforward neural network
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Predictor-based sampled-data output-feedback control for feedforward nonlinear time-delay systems
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作者 Wenjie Zhang Weihao Pan +1 位作者 Xianfu Zhang Qingrong Liu 《Control Theory and Technology》 2025年第1期105-117,共13页
This paper studies global stabilization via predictor-based sampled-data output feedback for a class of feedforward nonlinear time-delay systems.Note that the traditional sampled-data observer via zero-order holder ma... This paper studies global stabilization via predictor-based sampled-data output feedback for a class of feedforward nonlinear time-delay systems.Note that the traditional sampled-data observer via zero-order holder may result in the performance degradation of the observer.In this paper,an improved predictor-based observer is designed to compensate for the influence of the unmeasurable states,sampling errors and output delay.In addition,a sampled-data output-feedback controller is also constructed using the gain scaling technique.By the Lyapunov-Krasovskii functional method,the global exponential stability of the resulting closed-loop system can be guaranteed under some sufficient conditions.The simulation results are provided to demonstrate the main results. 展开更多
关键词 feedforward nonlinear systems Time delay Predictor-based observer Sampled-data output-feedback controller
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An Iterative Tuning Method for Feedforward Control of Parallel Manipulators Considering Nonlinear Dynamics
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作者 Xiaojian Wang Jun Wu 《Chinese Journal of Mechanical Engineering》 2025年第1期295-305,共11页
Feedforward control is one of the most effective control techniques to increase the robot’s tracking accuracy.However,most of the dynamic models used in the feedforward controllers are linearly simplified such that t... Feedforward control is one of the most effective control techniques to increase the robot’s tracking accuracy.However,most of the dynamic models used in the feedforward controllers are linearly simplified such that the nonlinear and time-varying characteristics of dynamics in the workspace are ignored.In this paper,an iterative tuning method for feedforward control of parallel manipulators by taking nonlinear dynamics into account is proposed.Based on the robot rigid-body dynamic model,a feedforward controller considering the dynamic nonlinearity is presented.An iterative tuning method is given to iteratively update the feedforward controller by minimizing the root mean square(RMS)of the joint errors at each cycle.The effectiveness and extrapolation capability of the proposed method are validated through the experiments on a 2-DOF parallel manipulator.This research proposes an iterative tuning method for feedforward control of parallel manipulators considering nonlinear dynamics,which has better extrapolation capability in the whole workspace of manipulators. 展开更多
关键词 Parallel manipulator Dynamic model feedforward control Iterative learning control Parameter design
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Predicting Concrete Strength Using Data Augmentation Coupled with Multiple Optimizers in Feedforward Neural Networks
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作者 Sandeerah Choudhary Qaisar Abbas +3 位作者 Tallha Akram Irshad Qureshi Mutlaq B.Aldajani Hammad Salahuddin 《Computer Modeling in Engineering & Sciences》 2025年第11期1755-1787,共33页
The increasing demand for sustainable construction practices has led to growing interest in recycled aggregate concrete(RAC)as an eco-friendly alternative to conventional concrete.However,predicting its compressive st... The increasing demand for sustainable construction practices has led to growing interest in recycled aggregate concrete(RAC)as an eco-friendly alternative to conventional concrete.However,predicting its compressive strength remains a challenge due to the variability in recycled materials and mix design parameters.This study presents a robust machine learning framework for predicting the compressive strength of recycled aggregate concrete using feedforward neural networks(FFNN),Random Forest(RF),and XGBoost.A literature-derived dataset of 502 samples was enriched via interpolation-based data augmentation and modeled using five distinct optimization techniques within MATLAB’s Neural Net Fitting module:Bayesian Regularization,Levenberg-Marquardt,and three conjugate gradient variants—Powell/Beale Restarts,Fletcher-Powell,and Polak-Ribiere.Hyperparameter tuning,dropout regularization,and early stopping were employed to enhance generalization.Comparative analysis revealed that FFNN outperformed RF and XGBoost,achieving an R2 of 0.9669.To ensure interpretability,accumulated local effects(ALE)along with partial dependence plots(PDP)were utilized.This revealed trends consistent with the pre-existent domain knowledge.This allows estimation of strength from the properties of the mix without extensive lab testing,permitting designers to track the performance and sustainability trends in concrete mix designs while promoting responsible construction and demolition waste utilization. 展开更多
关键词 feedforward neural networks recycled aggregates compressive strength prediction optimization techniques data augmentation grid search
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An Improved Feedforward Control Strategy to Promote the Rapidity of PMSM Servo System and Reduce Overshoot Oscillation
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作者 Wentao Zhang Yan Zhang +1 位作者 Yongxiang Xu Jibin Zou 《CES Transactions on Electrical Machines and Systems》 2025年第1期100-109,共10页
Under the condition of large inertia load,the stability of the servo system is more sensitive to the response speed and more likely to produce overshoot oscillations.In order to realize the requirements of high-precis... Under the condition of large inertia load,the stability of the servo system is more sensitive to the response speed and more likely to produce overshoot oscillations.In order to realize the requirements of high-precision and fast-response control of permanent magnet synchronous motor(PMSM)under large inertia load,an improved feedforward control strategy based on position impulse compensation and PD iterative algorithm is proposed to improve the response speed of the PMSM servo system and reduce the overshoot oscillation.This paper analyzes the mathematical models of the speed servo system and position servo system of the PMSM,calculates position overshoot impulse of the PMSM servo system,and improves the traditional feedforward control strategy to reversely compensate when the position is about to overshoot.Moreover,in order to further reduce the position overshoot,the PD iterative control algorithm is superimposed without increasing the complexity of the algorithm.The input signal is continuously corrected through multiple runs to achieve a smoother response control.The effectiveness of the proposed feedforward control strategy is verified by simulation and experiment. 展开更多
关键词 feedforward control Overshoot impulse Permanent magnet synchronous motor PD iterative control
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Feedforward compensation-based L1 adaptive control for aeropropulsion system test facility and hardware-in-the-loop verification
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作者 Jiashuai LIU Ai HE +1 位作者 Xitong PEI Yifu LONG 《Chinese Journal of Aeronautics》 2025年第3期85-95,共11页
Aeropropulsion System Test Facility (ASTF) is required to accurately control the pressure and temperature of the airflow to test the performance of the aero-engine. However, the control accuracy of ASTF is significant... Aeropropulsion System Test Facility (ASTF) is required to accurately control the pressure and temperature of the airflow to test the performance of the aero-engine. However, the control accuracy of ASTF is significantly affected by the flow disturbance caused by aero-engine acceleration and deceleration. This would reduce the credibility of ASTF’s test results for the aero-engine. Therefore, first, this paper proposes a feedforward compensation-based L1 adaptive control method for ASTF to address this problem. The baseline controller is first designed based on ideal uncoupled closed-loop dynamics to achieve dynamic decoupling. Then, L1 adaptive control is adopted to deal with various uncertainties and ensure good control performance. To further enhance the anti-disturbance performance, a feedforward strategy based on disturbance prediction is designed in the L1 adaptive control framework to compensate for the unmatched flow disturbance, which cannot be measured directly. In addition, this strategy takes into account the effects of actuator dynamics. With this method, the feedforward term can be determined from the nominal model parameters despite uncertainties. Finally, to demonstrate the effectiveness of the proposed method, various comparative experiments are performed on a hardware-in-the-loop system of ASTF. The experimental results show that the proposed method possesses excellent tracking performance, anti-disturbance performance and robustness. 展开更多
关键词 L_(1)adaptive control feedforward compensation DISTURBANCE COUPLING Hardware-in-the-loop simulation Aeropropulsion system test facility
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Real-Time Ship Roll Prediction via a Novel Stochastic Trainer-Based Feedforward Neural Network
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作者 XU Dong-xing YIN Jian-chuan 《China Ocean Engineering》 2025年第4期608-620,共13页
Enhancing the accuracy of real-time ship roll prediction is crucial for maritime safety and operational efficiency.To address the challenge of accurately predicting the ship roll status with nonlinear time-varying dyn... Enhancing the accuracy of real-time ship roll prediction is crucial for maritime safety and operational efficiency.To address the challenge of accurately predicting the ship roll status with nonlinear time-varying dynamic characteristics,a real-time ship roll prediction scheme is proposed on the basis of a data preprocessing strategy and a novel stochastic trainer-based feedforward neural network.The sliding data window serves as a ship time-varying dynamic observer to enhance model prediction stability.The variational mode decomposition method extracts effective information on ship roll motion and reduces the non-stationary characteristics of the series.The energy entropy method reconstructs the mode components into high-frequency,medium-frequency,and low-frequency series to reduce model complexity.An improved black widow optimization algorithm trainer-based feedforward neural network with enhanced local optimal avoidance predicts the high-frequency component,enabling accurate tracking of abrupt signals.Additionally,the deterministic algorithm trainer-based neural network,characterized by rapid processing speed,predicts the remaining two mode components.Thus,real-time ship roll forecasting can be achieved through the reconstruction of mode component prediction results.The feasibility and effectiveness of the proposed hybrid prediction scheme for ship roll motion are demonstrated through the measured data of a full-scale ship trial.The proposed prediction scheme achieves real-time ship roll prediction with superior prediction accuracy. 展开更多
关键词 ship roll prediction data preprocessing strategy sliding data widow improved black widow optimization algorithm stochastic trainer feedforward neural network
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A Novel Feedforward Hybrid Active Noise Control System with Narrowband Frequency Adaptive Estimation and Error Separation
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作者 PANG Mingrui LIU Yifei LIU Jian 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第5期638-647,共10页
The conventional feedforward hybrid active noise control(FFHANC)system combines the advantages of the feedforward narrowband active noise control(FFNANC)system and the feedforward broadband active noise control(FFBANC... The conventional feedforward hybrid active noise control(FFHANC)system combines the advantages of the feedforward narrowband active noise control(FFNANC)system and the feedforward broadband active noise control(FFBANC)system.To enhance its adaptive adjustment capability under frequency mismatch(FM)conditions,this paper introduces a narrowband frequency adaptive estimation module into the conventional FFHANC system.This module integrates an autoregressive(AR)model and a linear cascaded adaptive notch filter(LCANF),enabling accurate reference signal frequency estimation even under significant FM.Furthermore,in order to improve the coherence between narrowband and broadband components in the system’s error signal and its corresponding control filter for the conventional FFHANC system,this paper proposes an algorithm based on autoregressive bandpass filter bank(AR-BPFB)for error separation.Simulation results demonstrate that the proposed FFHANC system maintains robust performance under high FM conditions and effectively suppresses hybrid-band noise.The AR-BPFB algorithm significantly elevates the convergence speed of the FFHANC system. 展开更多
关键词 active noise control feedforward hybrid active noise control(FFHANC)system autoregressive(AR)model linear cascaded adaptive notch filter(LCANF) bandpass filter bank(BPFB) error separation
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基于双前馈-改进串级PID的设施蔬菜表型信息采集稳衡云台设计与试验
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作者 于海业 张楠 +4 位作者 潘智浩 付含冰 张晨曦 姜然哲 张蕾 《农业机械学报》 北大核心 2026年第1期30-40,共11页
针对设施蔬菜表型信息采集过程中,由于地形不平整产生3~6 Hz振动造成采集装置出现高频小角度倾斜、动态响应滞后,进而导致采集图像分辨率下降等问题,设计了基于重力补偿角加速度双前馈改进串级PID复合控制系统的适用设施表型采集装置的... 针对设施蔬菜表型信息采集过程中,由于地形不平整产生3~6 Hz振动造成采集装置出现高频小角度倾斜、动态响应滞后,进而导致采集图像分辨率下降等问题,设计了基于重力补偿角加速度双前馈改进串级PID复合控制系统的适用设施表型采集装置的稳衡云台。硬件上,针对30 cm窄行距与多源传感器搭载需求,设计300 mm×280 mm×250 mm单臂稳衡云台,整机仅5 kg,最大负载能力达15 kg。集成X Y Z轴重心滑轨,将负载重心偏差控制在±5 mm,由此引起的重力矩波动小于0.5 N·m。控制策略上,通过线性拟合构建重力补偿前馈模型(R^(2)=0.9912),以抵消重力矩干扰。提出内环速度环叠加外环位置环的改进串级PID,引入积分分离、积分限幅及误差过零复位机制,解决传统PID小角度调整积分饱和问题,稳态误差控制在0.1°以内。融合载体与云台双IMU角加速度前馈,抵消采集车2~3 m/s^(2)启停/转向带来的惯性扰动。运行效果验证试验表明,复合控制使系统阶跃响应时间缩短80%且全程无超调。采集车以0.5 m/s行驶时,云台三轴角度围绕目标值小幅度振荡,其中横滚轴角度±0.5°、俯仰轴角度±0.3°、航向轴角度±0.2°,满足设施蔬菜表型采集对姿态稳定性的要求。 展开更多
关键词 设施蔬菜 表型信息 稳衡云台 双前馈 串级PID
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基于模糊前馈控制的关节型机器人振动抑制算法
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作者 甘亚辉 徐升 +2 位作者 韩早 李昂 徐杰威 《中山大学学报(自然科学版)(中英文)》 北大核心 2026年第1期43-51,共9页
提出了一种基于前馈补偿与模糊控制的混合控制策略。该方法基于精确动力学模型进行前馈控制,同时引入模糊逻辑以提升控制器的性能。首先,对机器人运行中产生振动的主要因素进行分析,并选定ISO9283标准中的估计准确度作为性能评估指标,... 提出了一种基于前馈补偿与模糊控制的混合控制策略。该方法基于精确动力学模型进行前馈控制,同时引入模糊逻辑以提升控制器的性能。首先,对机器人运行中产生振动的主要因素进行分析,并选定ISO9283标准中的估计准确度作为性能评估指标,用于量化轨迹跟踪误差与振动抑制的效果。文中将提出的模糊前馈控制算法与传统PD控制、结合前馈补偿的PD控制进行了对比。仿真结果表明,该方法在轨迹跟踪精度和振动抑制效果方面均表现出显著提升,验证了方法的有效性与优越性。 展开更多
关键词 关节型机器人 动力学模型 前馈控制 模糊控制 振动抑制
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基于加权比例微分的并网逆变器PCC电压前馈策略
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作者 李志军 王雅欣 +1 位作者 邱春阳 刘士杰 《电工电能新技术》 北大核心 2026年第2期57-66,共10页
随着高比例可再生能源的接入,电网呈现弱电网特性。弱电网下,电网电压中存在的大量背景谐波会对并网逆变器的并网电流电能质量造成影响。通常采用电网电压前馈策略对背景谐波进行抑制,但由于电网阻抗的存在,采用传统前馈策略会降低并网... 随着高比例可再生能源的接入,电网呈现弱电网特性。弱电网下,电网电压中存在的大量背景谐波会对并网逆变器的并网电流电能质量造成影响。通常采用电网电压前馈策略对背景谐波进行抑制,但由于电网阻抗的存在,采用传统前馈策略会降低并网逆变器的稳定裕度,引发谐波振荡问题甚至导致并网系统的不稳定。针对这一问题,本文提出一种基于加权比例微分的公共耦合点(PCC)电压前馈策略。首先,推导并建立了LCL型的并网逆变器等效阻抗模型,利用阻抗法分析弱电网下引入传统电压前馈策略对系统稳定性的影响,并通过绘制引入前馈前后并网逆变器等效输出阻抗比值的矢量图来揭示其幅相特性随频率的变化情况,在此基础上提出在前馈通道引入加权比例微分环节,并选取适宜的权重系数,实现对弱电网下并网逆变器谐波谐振的有效抑制。最后,基于Matlab/Simulink平台进行了仿真实验,验证了本文所提策略的可行性和有效性。 展开更多
关键词 并网逆变器 弱电网 PCC电压前馈 谐波谐振 稳定性
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直接三相-单相模块化多电平矩阵变流器前馈解耦有源消弧控制方法
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作者 王文 童宇轩 +4 位作者 岳雨霏 肖启龙 朱维俊 唐欣 曾祥君 《电网技术》 北大核心 2026年第3期1300-1309,I0118-I0121,共14页
由于输入输出频率相同,直接三相-单相模块化多电平矩阵变流器(modular multilevel matrix converter,M3C)在配电网有源消弧应用中存在变量相互耦合导致子模块电容电压难以快速控制的问题,影响M3C的稳定运行与故障快速消弧。针对这一问题... 由于输入输出频率相同,直接三相-单相模块化多电平矩阵变流器(modular multilevel matrix converter,M3C)在配电网有源消弧应用中存在变量相互耦合导致子模块电容电压难以快速控制的问题,影响M3C的稳定运行与故障快速消弧。针对这一问题,提出了M3C前馈解耦有源电压消弧控制方法。首先,利用ΣΔ-αβ0坐标变换构建三相-单相直接M3C电路模型,揭示了M3C同频工况下的欠驱动特性;然后,通过注入多频组合的环流与共模电压实现完全驱动,对各桥臂平均功率进行分析,发现电容电压均衡控制系统是一个多变量耦合的多输入多输出系统。基于上述耦合关系,利用前馈解耦思想,将耦合项前馈到对应通道,使得初始的多输入多输出系统转变为多个完全解耦的单输入单输出系统,提高了均压控制系统的动态响应速度和故障电弧快速处置能力。MATLAB/Simulink仿真和硬件在环实验结果表明,配电网发生单相接地故障时,该方法能够实现M3C各桥臂电容电压快速均衡以及接地故障可靠消弧。 展开更多
关键词 有源消弧 模块化多电平矩阵变流器 同频变换 前馈解耦控制 模块电容电压均衡
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基于地震属性智能融合的稀井网辫状河储层构型精细表征——以渤海湾盆地C-6油田馆陶组为例
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作者 尹志军 李彦泽 +3 位作者 张建民 张章 侯东梅 陈冰歌 《沉积学报》 北大核心 2026年第1期279-291,共13页
【目的】C-6油田是渤海海域亿吨级曹妃甸油田群主力油田之一,其主力开发层系馆陶组Ⅲ油组为一套富砂的辫状河沉积,内部储层连通性尚不明确,制约油田开发效果。【方法】采用基于深度前馈神经网络(Deep Feed-Forward Neural Network,DFNN... 【目的】C-6油田是渤海海域亿吨级曹妃甸油田群主力油田之一,其主力开发层系馆陶组Ⅲ油组为一套富砂的辫状河沉积,内部储层连通性尚不明确,制约油田开发效果。【方法】采用基于深度前馈神经网络(Deep Feed-Forward Neural Network,DFNN)地震属性智能融合技术,在有限测井信息的标定下,对油田辫状河储层四级构型单元空间分布进行了精细表征。【结果】综合多井测井解释,C-6油田馆陶组Ⅲ油组主要发育心滩和辫状河道两种类型四级构型单元,其中心滩储层厚度大,物性较好,是研究区主要发育的储层构型单元。在地震属性提取与单井岩性和物性参数相关性分析的基础上,选取反射强度、相对阻抗、甜点、瞬时振幅、均方根振幅5种属性基于孔隙度监督的DFNN智能融合,大幅提高了辫状河储层砂体及其边界的探测能力。C-6油田馆陶组Ⅲ油组主体为北东—南西向辫流带,内部划分出呈菱形的15个心滩四级构型单元,分流河道四级构型单元呈窄条带状环绕在心滩周围,垂向上心滩互相切叠,形成“大心滩—小河道”的平面构型组合样式。【结论】基于地震属性智能融合的储层构型精细表征深化了稀井网控制的辫状河储层连通性认识,为C-6油田开发方案的调整提供了直接的地质依据,对海上稀井网条件下相同沉积类型油田的储层构型精细表征具有一定借鉴意义。 展开更多
关键词 辫状河 储层构型 深度前馈神经网络 馆陶组 渤海湾盆地
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融合对比学习的双边序列推荐
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作者 王巍 王亚飞 郭嘉梁 《计算机工程与设计》 北大核心 2026年第2期520-527,共8页
双边序列推荐解决了传统序列推荐只考虑单方面用户的缺陷,但其通过单一的预测任务来训练模型参数会受到数据稀疏的困扰,难以从双方用户行为序列层面获得准确的数据表征,因此提出一种融合对比学习的双边序列模型。在双边序列模型中引入... 双边序列推荐解决了传统序列推荐只考虑单方面用户的缺陷,但其通过单一的预测任务来训练模型参数会受到数据稀疏的困扰,难以从双方用户行为序列层面获得准确的数据表征,因此提出一种融合对比学习的双边序列模型。在双边序列模型中引入对比学习框架作为辅助推荐任务,通过数据增强的方式从数据中提取监督信号;调整多头注意力层和前馈层位置,使编码器更好的捕捉用户序列中的局部依赖;通过联合序列推荐任务和对比学习任务优化模型参数,实验结果表明,本文模型与8个对比模型相比性能均有显著提升,验证了提出的改进双边序列模型的有效性。 展开更多
关键词 数据增强 对比学习 多头注意力 前馈网络 双边序列推荐 序列推荐 数据稀疏
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前馈控制干预联合综合运动在慢性肾脏病5期血液透析患者中的应用
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作者 陈英 王丹 《河南医学研究》 2026年第1期161-164,共4页
目的观察前馈控制干预联合综合运动在慢性肾脏病(CKD)5期患者中的应用效果。方法回顾分析,收集2022年4—9月于郑州市第一人民医院完成血液透析治疗和综合运动干预的30例CKD5期患者资料,作为对照组;收集2022年10月至2023年3月于医院完成... 目的观察前馈控制干预联合综合运动在慢性肾脏病(CKD)5期患者中的应用效果。方法回顾分析,收集2022年4—9月于郑州市第一人民医院完成血液透析治疗和综合运动干预的30例CKD5期患者资料,作为对照组;收集2022年10月至2023年3月于医院完成血液透析治疗和前馈控制干预联合综合运动干预的30例CKD 5期患者资料,作为观察组。两组患者干预时间均为3个月。记录干预前后心肺耐力相关指标水平[最大摄氧量(VO_(2 max))和代谢当量(METs)]、生活质量[采用肾脏疾病生活质量简表(KDQOL-SFTM 1.3)评估];记录患者干预期间并发症发生情况。结果干预前,两组患者心肺耐力、生活质量评分比较,差异无统计学意义(P>0.05),干预后,两组患者心肺耐力指标水平升高、生活质量量表评分升高,且观察组高于对照组(P<0.05);观察组并发症总发生率低于对照组(P<0.05)。结论前馈控制干预联合综合运动用于CKD 5期血液透析患者,能更好地提高患者心肺耐力,患者干预期间并发症发生情况减少,生活质量明显改善。 展开更多
关键词 慢性肾脏病5期 血液透析 前馈控制 综合运动 心肺耐力 生活质量 并发症
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