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COMPENSATION CONTROL OF REAL-TIME UNBALANCE FORCE FOR ACTIVE MAGNETIC BEARING SYSTEM 被引量:3
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作者 高辉 徐龙祥 朱益利 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第2期183-191,共9页
Aiming at the stability and others properties of active magnetic bearing (AMB) system influenced by the periodic unbalance stimulation synchronous with rotor rotational speed, a new real-time adaptive feed-forward u... Aiming at the stability and others properties of active magnetic bearing (AMB) system influenced by the periodic unbalance stimulation synchronous with rotor rotational speed, a new real-time adaptive feed-forward unbalance force compensation scheme is proposed based on variable step-size least mean square(LMS) algorithm as the feed-forward compensation controller. The controller can provide some suitable sinusoidal signals to com- pensate the feedback unbalance response signals synchronous with the rotary frequency, then reduce the fluctua- tion of the control currents and weaken the active control of AMB system. The variable step-size proportional to the rotational frequency is deduced by analyzing the principle of normal LMS algorithm and its deficiency in the application of real-time filtering of AMB system. Experimental results show that the new method can implement real-time unbalance force compensation in a wide frequency band, reduce the effect of unbalance stimulant force on the housing of AMB system, and provide convenience to improve rotational speed. 展开更多
关键词 active magnetic bearing variable step-size LMS algorithm bandwidth~ real-time unbalance forcecompensation~ adaptive filter
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Application of A* Algorithm for Real-time Path Re-planning of an Unmanned Surface Vehicle Avoiding Underwater Obstacles 被引量:9
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作者 Thanapong Phanthong Toshihiro Maki +2 位作者 Tamaki Ura Takashi Sakamaki Pattara Aiyarak 《Journal of Marine Science and Application》 2014年第1期105-116,共12页
This paper describes path re-planning techniques and underwater obstacle avoidance for unmanned surface vehicle(USV) based on multi-beam forward looking sonar(FLS). Near-optimal paths in static and dynamic environment... This paper describes path re-planning techniques and underwater obstacle avoidance for unmanned surface vehicle(USV) based on multi-beam forward looking sonar(FLS). Near-optimal paths in static and dynamic environments with underwater obstacles are computed using a numerical solution procedure based on an A* algorithm. The USV is modeled with a circular shape in 2 degrees of freedom(surge and yaw). In this paper, two-dimensional(2-D) underwater obstacle avoidance and the robust real-time path re-planning technique for actual USV using multi-beam FLS are developed. Our real-time path re-planning algorithm has been tested to regenerate the optimal path for several updated frames in the field of view of the sonar with a proper update frequency of the FLS. The performance of the proposed method was verified through simulations, and sea experiments. For simulations, the USV model can avoid both a single stationary obstacle, multiple stationary obstacles and moving obstacles with the near-optimal trajectory that are performed both in the vehicle and the world reference frame. For sea experiments, the proposed method for an underwater obstacle avoidance system is implemented with a USV test platform. The actual USV is automatically controlled and succeeded in its real-time avoidance against the stationary undersea obstacle in the field of view of the FLS together with the Global Positioning System(GPS) of the USV. 展开更多
关键词 UNDERWATER OBSTACLE AVOIDANCE real-time pathre-planning A* algorithm SONAR image unmanned surface vehicle
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Application of the asynchronous advantage actor–critic machine learning algorithm to real-time accelerator tuning 被引量:3
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作者 Yun Zou Qing-Zi Xing +4 位作者 Bai-Chuan Wang Shu-Xin Zheng Cheng Cheng Zhong-Ming Wang Xue-Wu Wang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第10期133-141,共9页
This paper describes a real-time beam tuning method with an improved asynchronous advantage actor–critic(A3C)algorithm for accelerator systems.The operating parameters of devices are usually inconsistent with the pre... This paper describes a real-time beam tuning method with an improved asynchronous advantage actor–critic(A3C)algorithm for accelerator systems.The operating parameters of devices are usually inconsistent with the predictions of physical designs because of errors in mechanical matching and installation.Therefore,parameter optimization methods such as pointwise scanning,evolutionary algorithms(EAs),and robust conjugate direction search are widely used in beam tuning to compensate for this inconsistency.However,it is difficult for them to deal with a large number of discrete local optima.The A3C algorithm,which has been applied in the automated control field,provides an approach for improving multi-dimensional optimization.The A3C algorithm is introduced and improved for the real-time beam tuning code for accelerators.Experiments in which optimization is achieved by using pointwise scanning,the genetic algorithm(one kind of EAs),and the A3C-algorithm are conducted and compared to optimize the currents of four steering magnets and two solenoids in the low-energy beam transport section(LEBT)of the Xi’an Proton Application Facility.Optimal currents are determined when the highest transmission of a radio frequency quadrupole(RFQ)accelerator downstream of the LEBT is achieved.The optimal work points of the tuned accelerator were obtained with currents of 0 A,0 A,0 A,and 0.1 A,for the four steering magnets,and 107 A and 96 A for the two solenoids.Furthermore,the highest transmission of the RFQ was 91.2%.Meanwhile,the lower time required for the optimization with the A3C algorithm was successfully verified.Optimization with the A3C algorithm consumed 42%and 78%less time than pointwise scanning with random initialization and pre-trained initialization of weights,respectively. 展开更多
关键词 real-time BEAM tuning Parameter optimization ASYNCHRONOUS ADVANTAGE actor–critic algorithm Low-energy BEAM transport
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Ultrahigh spatiotemporal resolution beam signal reconstruction with bunch phase compensation
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作者 You-Ming Deng Yong-Bin Leng +2 位作者 Xing-Yi Xu Jian Chen Yi-Mei Zhou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期99-108,共10页
Various electromagnetic signals are excited by the beam in the acceleration and beam-diagnostic elements of a particle accelerator.It is important to obtain time-domain waveforms of these signals with high temporal re... Various electromagnetic signals are excited by the beam in the acceleration and beam-diagnostic elements of a particle accelerator.It is important to obtain time-domain waveforms of these signals with high temporal resolution for research,such as the study of beam–cavity interactions and bunch-by-bunch parameter measurements.Therefore,a signal reconstruction algorithm with ultrahigh spatiotemporal resolution and bunch phase compensation based on equivalent sampling is proposed in this paper.Compared with traditional equivalent sampling,the use of phase compensation and setting the bunch signal zero-crossing point as the time reference can construct a more accurate reconstructed signal.The basic principles of the method,simulation,and experimental comparison are also introduced.Based on the beam test platform of the Shanghai Synchrotron Radiation Facility(SSRF)and the method of experimental verification,the factors that affect the reconstructed signal quality are analyzed and discussed,including the depth of the sampled data,quantization noise of analog-to-digital converter,beam transverse oscillation,and longitudinal oscillation.The results of the beam experiments show that under the user operation conditions of the SSRF,a beam excitation signal with an amplitude uncertainty of 2%can be reconstructed. 展开更多
关键词 Turn-by-turn bunch phase compensation technique Equivalent sampling Signal reconstruction algorithm Ultrahigh spatiotemporal resolution SSRF
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Novel Real-Time Seam Tracking Algorithm Based on Vector Angle and Least Square Method 被引量:1
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作者 Guanhao Liang Qingsheng Luo +1 位作者 Zhuo Ge Xiaoqing Guan 《Journal of Beijing Institute of Technology》 EI CAS 2017年第2期150-157,共8页
Real-time seam tracking can improve welding quality and enhance welding efficiency during the welding process in automobile manufacturing.However,the teaching-playing welding process,an off-line seam tracking method,i... Real-time seam tracking can improve welding quality and enhance welding efficiency during the welding process in automobile manufacturing.However,the teaching-playing welding process,an off-line seam tracking method,is still dominant in automobile industry,which is less flexible when welding objects or situation change.A novel real-time algorithm consisting of seam detection and generation is proposed to track seam.Using captured 3D points,space vectors were created between two adjacent points along each laser line and then a vector angle based algorithm was developed to detect target points on the seam.Least square method was used to fit target points to a welding trajectory for seam tracking.Furthermore,the real-time seam tracking process was simulated in MATLAB/Simulink.The trend of joint angles vs.time was logged and a comparison between the off-line and the proposed seam tracking algorithm was conducted.Results show that the proposed real-time seam tracking algorithm can work in a real-time scenario and have high accuracy in welding point positioning. 展开更多
关键词 real-time seam tracking real-time seam detection laser scanner vector angle leastsquare method algorithm research
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Improved chirp scaling algorithm integrated motion compensation for parallel-track bistatic synthetic aperture radar
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作者 齐春东 曾涛 李枫 《Journal of Beijing Institute of Technology》 EI CAS 2011年第4期536-539,共4页
To compensate motion errors of images from the parallel-track bistatic synthetic aperture radar(BiSAR),an improved chirp scaling algorithm(CSA) is proposed.Since velocity vector of the moving aircrafts in the para... To compensate motion errors of images from the parallel-track bistatic synthetic aperture radar(BiSAR),an improved chirp scaling algorithm(CSA) is proposed.Since velocity vector of the moving aircrafts in the parallel-track BiSAR system can not remain invariant in an aperture,an actual aperture is divided into subapertures so that it is reasonable to assume that the aircrafts move with constant acceleration vector in a subaperture.Based on this model,an improved CSA is derived.The new phase factors incorporate three-dimensional acceleration and velocity.The motion compensation procedure is integrated into the CSA without additional operation required.The simulation results show that the presented algorithm can efficiently resolve motion compensation for parallel-track BiSAR. 展开更多
关键词 chirp scaling algorithm parallel-track bistatic synthetic aperture radar motion compensation
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Packet Scheduling Algorithm for Real-Time Services in Broadband WMAN
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作者 Zhang Hanyi, Su Xin (Wireless and Mobile Communication Technology R&D Center of Tsinghua University, Tsinghua National Laboratory for Information Science and Technology, Beijing 100084 , China ) 《ZTE Communications》 2009年第4期45-48,共4页
Packet scheduling algorithm is the key technology to guarantee Quality of Service (QoS) and balance the fairness between users in broadband Wireless Metropolitan Area Network (WMAN). Based on the research of Proportio... Packet scheduling algorithm is the key technology to guarantee Quality of Service (QoS) and balance the fairness between users in broadband Wireless Metropolitan Area Network (WMAN). Based on the research of Proportional Fairness (PF) algorithm and Modified Largest Weighted Delay First (M-LWDF) algorithm, a new packet scheduling algorithm for real-time services in broadband WMAN, called Enhanced M-LWDF (EM-LWDF), was proposed. The algorithm phases in new information to measure the load of service queues and updates the state parameters in real-time way, which remarkably improves system performance.Simulation results show that comparing with M-LWDF algorithm, the proposed algorithm is advantageous in performances of queuing delay and fairness while guaranteeing system throughput. 展开更多
关键词 Packet Scheduling algorithm for real-time Services in Broadband WMAN QoS OFDMA Simulation real WIMAX IEEE EM
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A Mixed Real-time Algorithm for the Forward Kinematics of Stewart Parallel Manipulator
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作者 王孙安 万亚民 《Journal of Electronic Science and Technology of China》 2006年第2期173-180,共8页
Aimed at the real-time forward kinematics solving problem of Stewart parallel manipulator in the control course, a mixed algorithm combining immune evolutionary algorithm and numerical iterative scheme is proposed. Fi... Aimed at the real-time forward kinematics solving problem of Stewart parallel manipulator in the control course, a mixed algorithm combining immune evolutionary algorithm and numerical iterative scheme is proposed. Firstly taking advantage of simpleness of inverse kinematics, the forward kinematics is transformed to an optimal problem. Immune evolutionary algorithm is employed to find approximate solution of this optimal problem in manipulator's workspace. Then using above solution as iterative initialization, a speedy numerical iterative scheme is proposed to get more precise solution. In the manipulator running course, the iteration initialization can be selected as the last period position and orientation. Because the initialization is closed to correct solution, solving precision is high and speed is rapid enough to satisfy real-time requirement. This mixed forward kinematics algorithm is applied to real Stewart parallel manipulator in the real-time control course. The examination result shows that the algorithm is very efficient and practical. 展开更多
关键词 stewart parallel manipulator forward kinematics immune evolutionary algorithm numerical iterative scheme real-time control
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Evolutionary-assisted reinforcement learning for reservoir real-time production optimization under uncertainty 被引量:2
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作者 Zhong-Zheng Wang Kai Zhang +6 位作者 Guo-Dong Chen Jin-Ding Zhang Wen-Dong Wang Hao-Chen Wang Li-Ming Zhang Xia Yan Jun Yao 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期261-276,共16页
Production optimization has gained increasing attention from the smart oilfield community because it can increase economic benefits and oil recovery substantially.While existing methods could produce high-optimality r... Production optimization has gained increasing attention from the smart oilfield community because it can increase economic benefits and oil recovery substantially.While existing methods could produce high-optimality results,they cannot be applied to real-time optimization for large-scale reservoirs due to high computational demands.In addition,most methods generally assume that the reservoir model is deterministic and ignore the uncertainty of the subsurface environment,making the obtained scheme unreliable for practical deployment.In this work,an efficient and robust method,namely evolutionaryassisted reinforcement learning(EARL),is proposed to achieve real-time production optimization under uncertainty.Specifically,the production optimization problem is modeled as a Markov decision process in which a reinforcement learning agent interacts with the reservoir simulator to train a control policy that maximizes the specified goals.To deal with the problems of brittle convergence properties and lack of efficient exploration strategies of reinforcement learning approaches,a population-based evolutionary algorithm is introduced to assist the training of agents,which provides diverse exploration experiences and promotes stability and robustness due to its inherent redundancy.Compared with prior methods that only optimize a solution for a particular scenario,the proposed approach trains a policy that can adapt to uncertain environments and make real-time decisions to cope with unknown changes.The trained policy,represented by a deep convolutional neural network,can adaptively adjust the well controls based on different reservoir states.Simulation results on two reservoir models show that the proposed approach not only outperforms the RL and EA methods in terms of optimization efficiency but also has strong robustness and real-time decision capacity. 展开更多
关键词 Production optimization Deep reinforcement learning Evolutionary algorithm real-time optimization Optimization under uncertainty
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A nonlinear model reference adaptive inverse control algorithm with pre-compensator 被引量:2
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作者 XIAO Bin YANG Tie-Jun LIU Zhi-Gang 《Journal of Marine Science and Application》 2005年第4期34-42,共9页
In this paper, the reduced-order modeling (ROM) technology and its corresponding linear theory are expanded from the linear dynamic system to the nonlinear one, and H∞ control theory is employed in the frequency do... In this paper, the reduced-order modeling (ROM) technology and its corresponding linear theory are expanded from the linear dynamic system to the nonlinear one, and H∞ control theory is employed in the frequency domain to design some nonlinear system' s pre-compensator in some special way. The adaptive model inverse control (AMIC)theory coping with nonlinear system is improved as well. Such is the model reference adaptive inverse control with pre-compensator (PCMRAIC). The aim of that algorithm is to construct a strategy of control as a whole. As a practical example of the application, the nunlerical simulation has been given on matlab software packages. The numerical result is given. The proposed strategy realizes the linearization control of nonlinear dynamic system. And it carries out a good performance to deal with the nonlinear system. 展开更多
关键词 ROM technology AMIC algorithm nonlinear system compensator in frequency domain linearization control.
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Ballistic deficit compensation method for a large-volume HPGe detector at high count rates 被引量:2
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作者 Chuan-Yun Xiong Ming-Zhe Liu +1 位作者 Zhuo Zuo Xian-Guo Tuo 《Nuclear Science and Techniques》 SCIE CAS CSCD 2016年第3期123-131,共9页
A large-volume HPGe detector normally has a severe ballistic deficit due to its long rise time of the output signals.Despite the trapezoidal shaping algorithm adopted as a remedy to deal with the signals,the algorithm... A large-volume HPGe detector normally has a severe ballistic deficit due to its long rise time of the output signals.Despite the trapezoidal shaping algorithm adopted as a remedy to deal with the signals,the algorithm cannot fully eliminate the ballistic deficit in the case of a high counting rate.To resolve the problem,we propose a ballistic deficit compensation method that is based on the measurement of rise time of the signals before shaping.We find that the ballistic deficit after trapezoidal shaping has little relation to the time constant,but shows a quadratic relationship with the rise time and has a negative correlation with the shaping time.In the case of high count rates,the high resolution is handled by fitting the curve to the rise time and the amplitude deficit of the signal after shaping and by compensating for the signal amplitude after trapezoidal shaping.Tests indicate that when the count rate is about 100 kcps,the resolution of Co-60 improves from traditional 2.32 up to 1.91 keV,thus reaching a higher level. 展开更多
关键词 高计数率 补偿方法 HPGE探测器 亏损 弹道 大体积 输出信号 上升时间
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Dynamic constraint and objective generation approach for real-time train rescheduling model under human-computer interaction
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作者 Kai Liu Jianrui Miao +2 位作者 Zhengwen Liao Xiaojie Luan Lingyun Meng 《High-Speed Railway》 2023年第4期248-257,共10页
Real-time train rescheduling plays a vital role in railway transportation as it is crucial for maintaining punctuality and reliability in rail operations.In this paper,we propose a rescheduling model that incorporates... Real-time train rescheduling plays a vital role in railway transportation as it is crucial for maintaining punctuality and reliability in rail operations.In this paper,we propose a rescheduling model that incorporates constraints and objectives generated through human-computer interaction.This approach ensures that the model is aligned with practical requirements and daily operational tasks while facilitating iterative train rescheduling.The dispatcher’s empirical knowledge is integrated into the train rescheduling process using a human-computer interaction framework.We introduce six interfaces to dynamically construct constraints and objectives that capture human intentions.By summarizing rescheduling rules,we devise a rule-based conflict detection-resolution heuristic algorithm to effectively solve the formulated model.A series of numerical experiments are presented,demonstrating strong performance across the entire system.Furthermore,theflexibility of rescheduling is enhanced through secondary analysis-driven solutions derived from the outcomes of humancomputer interactions in the previous step.This proposed interaction method complements existing literature on rescheduling methods involving human-computer interactions.It serves as a tool to aid dispatchers in identifying more feasible solutions in accordance with their empirical rescheduling strategies. 展开更多
关键词 real-time train rescheduling Human-computer interaction Rule-based heuristic algorithm Secondary rescheduling
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Research on Collaboration Theory of Distributed Measurement System and Real-Time of Communication Platform
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作者 SHENYan 《Journal of Electronic Science and Technology of China》 2005年第1期95-95,共1页
关键词 distributed measurement system agent technology swarm intellgence Particle Swarm Optimization algorithm Collaboration model Switched Ethernet real-time Scheduling AEROENGINE
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基于改进Super-Twisting滑模观测器的永磁同步电机无传感器控制
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作者 王涛 黄景春 +1 位作者 周行之 金靖 《西南交通大学学报》 北大核心 2025年第2期445-453,共9页
在无传感器控制宽调速范围内,传统super-twisting二阶滑模观测器算法在永磁同步电机中存在转子位置估计误差随速度变化而发生抖动的问题.为减小转子位置估计误差并提升电机调速控制性能,本文基于双曲函数提出一种改进的滑模观测器,并设... 在无传感器控制宽调速范围内,传统super-twisting二阶滑模观测器算法在永磁同步电机中存在转子位置估计误差随速度变化而发生抖动的问题.为减小转子位置估计误差并提升电机调速控制性能,本文基于双曲函数提出一种改进的滑模观测器,并设计定子电阻的在线辨识方案,同时开发扰动电压观测器以在线估计逆变器非线性引起的失真电压;最后,通过电机硬件在环实验测试进行验证.测试结果表明:位置估计误差减小7.6%,速度估计精度提高5.8%. 展开更多
关键词 永磁同步电机 无传感器控制 改进super-twisting算法 定子电阻在线辨识 逆变器非线性补偿
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基于随机逼近算法的线缆压降自补偿电源系统
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作者 张元园 李杰 +3 位作者 胡陈君 何淑典 李华 曹宇 《探测与控制学报》 北大核心 2025年第2期102-108,共7页
针对传统弹载测试系统电源无法自适应补偿线缆压降、动态负载情况下用电处无法获取精准的电压,影响电气性能的问题,提出一种基于随机逼近算法的电源系统。通过闭环控制思想实现对负载端电压的监测与实时补偿,以现场可编程门阵列(FPGA)... 针对传统弹载测试系统电源无法自适应补偿线缆压降、动态负载情况下用电处无法获取精准的电压,影响电气性能的问题,提出一种基于随机逼近算法的电源系统。通过闭环控制思想实现对负载端电压的监测与实时补偿,以现场可编程门阵列(FPGA)为主控芯片,控制高精度数字电位器进行迭代,使得负载电压逐步逼近理想电压。实验结果表明,该系统最大误差为19 mV,最高转换效率为93.3%,能够对线缆阻抗导致的压降进行自适应补偿,保证负载电压维持在较高精度,满足弹载测试系统对电源的要求。 展开更多
关键词 FPGA 压降补偿 闭环控制 随机逼近
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SVC的2DOF差分进化控制动态性能研究
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作者 张路锋 马家庆 +3 位作者 何志琴 吴钦木 陈昌盛 覃涛 《太阳能学报》 北大核心 2025年第1期472-479,共8页
为提高静止无功补偿器在风电机组进行无功补偿时其整流过程的动态性能和对电网谐波的抑制能力,对系统整流过程中的控制器进行改进。首先将静止无功补偿器的直流侧和风电系统整流后的直流侧并联,然后在电压外环上,基于分数阶微积分理论... 为提高静止无功补偿器在风电机组进行无功补偿时其整流过程的动态性能和对电网谐波的抑制能力,对系统整流过程中的控制器进行改进。首先将静止无功补偿器的直流侧和风电系统整流后的直流侧并联,然后在电压外环上,基于分数阶微积分理论设计分数阶PID控制器,并使用差分进化算法对其参数进行整定,在电流内环上,使用二自由度PID控制器来提高电流的稳定性和抗干扰能力。在此基础上在Matlab/Simulink仿真平台上搭建模型,仿真结果表明:提出的方法不仅是稳定的,而且与传统PI控制器、分数阶PID控制器以及基于差分进化优化算法的分数阶PID控制器相比,在响应速度和超调量等方面显著下降,具有较好的动态响应性能,进入稳态后的总谐波失真因素和纹波系数明显减小,提高电网对谐波的抑制能力。 展开更多
关键词 风电机组 静止无功补偿器 差分进化算法 分数阶微积分 二自由度PID控制器
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基于BEBLID描述子与SuperGlue补偿匹配改进的ORB-SLAM3算法
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作者 赵义武 王星朝 +3 位作者 黄丹丹 刘智 郭星辰 侯舒帆 《中国惯性技术学报》 北大核心 2025年第3期249-256,共8页
为了提高同时定位与地图构建(SLAM)系统的精确性和稳定性,在ORB-SLAM3的基础上提出了一种基于BEBLID描述子与SuperGlue补偿匹配的视觉SLAM算法。首先,对图像数据进行特征提取,计算BEBLID描述子,并利用这种二进制描述子进行特征匹配;然后... 为了提高同时定位与地图构建(SLAM)系统的精确性和稳定性,在ORB-SLAM3的基础上提出了一种基于BEBLID描述子与SuperGlue补偿匹配的视觉SLAM算法。首先,对图像数据进行特征提取,计算BEBLID描述子,并利用这种二进制描述子进行特征匹配;然后,针对匹配效果不稳定的问题,采用SuperGlue算法对具备映射关系但未成功匹配的特征点对补偿匹配,以提高跟踪的稳定性。实验结果表明,相比于ORB-SLAM3算法,使用BEBLID描述子进行特征匹配能够平均降低16.08%的绝对轨迹误差;使用SuperGlue进行补偿匹配能够提高算法跟踪效果的稳定性。综合应用BEBLID描述子和SuperGlue补偿匹配策略,可以显著提高SLAM系统的鲁棒性。 展开更多
关键词 同时定位与地图构建 特征匹配 BEBLID描述子 SuperGlue算法 补偿匹配
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平面近场测量中一种极化探头补偿算法研究
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作者 刘伟康 贾云飞 刘星汛 《电子设计工程》 2025年第1期36-40,共5页
为研究天线特性,该研究采用近场测量技术计算天线的远场方向图,该技术具有成本低、速度快的优势。考虑到平面近场测量中探头参数对远场方向图的影响,该研究基于平面近远场变换算法,引入探头补偿技术和极化补偿技术。利用HFSS仿真得到待... 为研究天线特性,该研究采用近场测量技术计算天线的远场方向图,该技术具有成本低、速度快的优势。考虑到平面近场测量中探头参数对远场方向图的影响,该研究基于平面近远场变换算法,引入探头补偿技术和极化补偿技术。利用HFSS仿真得到待测天线远场仿真方向图,通过计算机算法构建,将近远场变换算法所得方向图与实际测得的远场方向图进行比较,验证算法的准确性。进一步结合极化补偿算法与探头补偿算法,与未修正的结果及远场方向图进行对比。结果显示,极化探头补偿算法能有效修正探头对远场方向图的影响,其不确定度超过近远场变换算法1.4295 dB,超过极化补偿算法0.9062 dB,确保了研究的客观性和独立性。 展开更多
关键词 天线近远场变换 探头补偿算法 极化补偿算法 天线平面近场仿真
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光电探测器暗电流宽温拟合算法研究
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作者 袁国振 任海兰 《光通信研究》 北大核心 2025年第1期77-82,共6页
【目的】为了消除光电探测器(PD)内正负(PN)结固有暗电流物理特性的影响,在提升探测器功率探测范围和扩宽探测器工作环境温度范围的同时提高PD探测精度,文章设计了一套在标定PD时应用的暗电流补偿算法。【方法】首先,通过分析光电二极... 【目的】为了消除光电探测器(PD)内正负(PN)结固有暗电流物理特性的影响,在提升探测器功率探测范围和扩宽探测器工作环境温度范围的同时提高PD探测精度,文章设计了一套在标定PD时应用的暗电流补偿算法。【方法】首先,通过分析光电二极管物理特性及PD内的硬件电路设计,建立光生电流与光功率间的数学模型,基于数学模型修正光功率与光生电压模数转换(ADC)值的曲线关系,实现在具体温度点下去除暗电流功率影响并补偿功率;其次,研究暗电流的温度特性,计算出少数温度条件下所需补偿暗电流的功率大小,利用少数温度点拟合扩展至宽温范围实现暗电流温度补偿;最后,搭建温控测试平台,利用光开关(OS)控制光电二极管入光功率大小,通过光功率探测仪记录PD实时入光功率大小,测试在不同温度条件以及入光功率下的PD精度值。【结果】实验表明,利用算法标定PD后,工作温度范围可从-5~55℃扩宽至-40~80℃,最低探测功率从-40下降至-68 dBm。在上述工作温度和探测范围下,软件算法计算上报的光功率与实际探测光功率的精度误差在±1 dB以内。【结论】采用文章所提算法对PD校准后能消除暗电流及噪声的影响,在宽温范围下能提高探测功率范围及探测精度。 展开更多
关键词 暗电流 光电探测器 宽温范围 低功探测 补偿算法
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中空间隔织物送经及张力控制研究
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作者 陈立乐 杨涛 +3 位作者 周玉峰 田秀峰 宋良 杜宇 《毛纺科技》 北大核心 2025年第4期111-117,共7页
为了解决中空间隔织物在织造过程中送绒量大的需求以及绒经张力波动大不易控制等缺陷,进行了W型中空间隔织物的织造工艺及张力影响因素的分析,提出一种基于全伺服控制的二次送绒张力控制方案。该方案结合了以气缸弹簧为动力源的双辊摆... 为了解决中空间隔织物在织造过程中送绒量大的需求以及绒经张力波动大不易控制等缺陷,进行了W型中空间隔织物的织造工艺及张力影响因素的分析,提出一种基于全伺服控制的二次送绒张力控制方案。该方案结合了以气缸弹簧为动力源的双辊摆动式张力调节装置,针对动态张力变化结合张力摆杆与角度传感器,利用增量式PID算法实时控制送经电机收放卷速度控制经纱张力。所设计的全伺服控制张力控制方案在高间距剑杆织机上调试。结果表明:该系统可实时调整送经轴的送经速度,将地经张力控制在8%、绒经张力的波动范围控制在10%以内,对地经及绒经张力的稳定有着良好的效果,满足绒高在5~80 mm之间大送绒量的织造工艺要求,为织物质量的提升提供了高效解决方案。 展开更多
关键词 大送绒量 二次送绒 双辊摆动式张力补偿 增量式PID算法 高间距双剑杆织机
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