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Hybrid Controller for Steady Speed of Agricultural Machinery on Slopes
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作者 WU Caicong XU Haisong GAO Xingyu 《农业机械学报》 北大核心 2026年第2期416-426,共11页
Steady speed control of agricultural machinery can improve operating quality and efficiency.To address the impact of farmland slope variations on the speed stability of unmanned operation agricultural machinery,a hybr... Steady speed control of agricultural machinery can improve operating quality and efficiency.To address the impact of farmland slope variations on the speed stability of unmanned operation agricultural machinery,a hybrid control method was proposed.This method included a hybrid controller composed of a slope-based controller and a proportional-integral-derivative(PID)controller.The speed of agricultural machinery was influenced by longitudinal forces,which were divided into two parts:one part was slope-related forces and conventional resistance,and the other was hard-to-estimate forces,such as sliding friction.For the first part,a slope-based controller was designed;for the second part,a PID controller was implemented.By combining these two controllers,the system can dynamically adjust the throttle opening and the brake master cylinder pressure,ensuring steady speed travel on sloping farmland.Simulation tests at a target speed of 7 km/h demonstrated that the proposed controller maintained a stable speed,achieving a root mean square error of 0.13 km/h and a mean absolute percentage error of 1.6%.Field tests on a practical experimental platform validated the method’s effectiveness,with results showing consistent control performance across varying slope conditions.The proposed controller demonstrated superior control performance.Experimental data verified that this method can achieve precise control of the agricultural machinery’s movement speed,meeting the stability requirements for agricultural operations. 展开更多
关键词 farmland slope PID controller steady speed control agricultural machinery unmanned operation
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Moving mirror speed compound control of the Fourier transform spectrometer based on T-method
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作者 HUANG Ying DUAN Juan +2 位作者 GUO Qian DING Lei HUA Jian-Wen 《红外与毫米波学报》 北大核心 2026年第1期137-147,共11页
傅里叶变换光谱仪是一种精密的红外探测仪器,它采用迈克尔逊式干涉分光方式,动镜是其中一个核心部件。动镜运动速度的均匀性和稳定性直接影响了后续干涉图的质量,所以必须对动镜进行高精度的运动控制。对于某些动镜低速应用场合的傅里... 傅里叶变换光谱仪是一种精密的红外探测仪器,它采用迈克尔逊式干涉分光方式,动镜是其中一个核心部件。动镜运动速度的均匀性和稳定性直接影响了后续干涉图的质量,所以必须对动镜进行高精度的运动控制。对于某些动镜低速应用场合的傅里叶光谱仪,常规的M法测速已经不能满足测速精度的要求了。另外,动镜低速运动时,速度稳定性更容易受外界力学扰动的影响。基于动镜低速运动的平稳性需求,文中对基于T法测速的动镜运动控制技术进行了研究,提出了求取速度实测值和速度期望值的高精度算法,并通过建立被控对象的数学模型和动力学方程,得到速度前馈控制量,进而设计了基于速度前馈的复合速度控制器。该设计的动镜速度控制算法由FPGA硬件平台实现,并应用于傅里叶光谱仪实验平台。实验结果表明,采用T法测速控制系统获得动镜运动匀速区速度峰峰值误差是0.0182,速度均方根值误差是0.0027。为测试文中动镜速度控制系统的抗干扰能力,在干涉仪安装平台动镜运动方向分别施加5 mg、7.5 mg、10 mg的正弦激励力,在每个给定量级的激励力下,进行了2~200 Hz频率范围内各频率点的扫描,实验结果表明,速度峰峰值误差和速度均方根值误差和正弦激励的幅值基本成正比例关系。在5 mg时各频率点的力学激励下,速度峰峰值误差最大是0.0724,速度均方根值误差最大是0.0225。从光谱稳定度和红外焦平面探测器采样间隔误差综合分析,5mg量级时的动镜速度均匀性可以满足系统这两方面需求,使得傅里叶光谱仪在微振动环境应用时也具有一定的抗干扰能力。该设计为傅里叶光谱仪低速高平稳性动镜速度控制的实现提供了一种技术途径,同时也使得傅里叶光谱仪有了更广阔的应用场景。 展开更多
关键词 傅里叶光谱仪 速度控制 T法测速 速度前馈 速度均匀性
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A Comprehensive Review of Torque and Speed Control Strategies for Switched Reluctance Motor Drives 被引量:1
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作者 Sreeram K Preetha P K +1 位作者 Javier Rodríguez-García Carlosálvarez-Bel 《CES Transactions on Electrical Machines and Systems》 2025年第1期46-75,共30页
Switched Reluctance Motors(SRMs),outfitted with rugged construction,good speed range,high torque density,and rare earth-free nature that outweigh induction motors(IM)and permanent magnet synchronous motor(PMSM),afford... Switched Reluctance Motors(SRMs),outfitted with rugged construction,good speed range,high torque density,and rare earth-free nature that outweigh induction motors(IM)and permanent magnet synchronous motor(PMSM),afford a broad range of applications in the domain of electric vehicles(EVs).Standard copper magnetic wire and low-carbon steel laminations are used to construct SRMs,which give them high efficiency in the range of 85-95%.Despite SRM's desirable features over traditional motor-speed drives,high torque ripples and radial distortions constrain their deployment in EVs.Precise rotor position is imperative for effective management of the speed and torque of SRMs.This paper provides an illustrative compendium on review of the torque-speed control and ripple mitigation techniques using design enhancements and control methods for SRM drives for EV applications.The various schemes were evaluated on their performance metricsoperational speed range,control complexity,practical realization,need for pre-stored parameters(look-up tables of current,inductance and torque profiles)and motor controller memory requirements.The findings provide valuable insights into balancing the gains and trade-offs associated with EV applications.Furthermore,they pinpoint opportunities for enhancement by analyzing the cost and technical aspects of different SRM controllers. 展开更多
关键词 Electric vehicles Switched reluctance motor Speed control Torque control Traction motor Torque ripple
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Challenges and suggestions for high-speed boundary layer transition control using surface microstructure 被引量:1
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作者 Jisen YUAN Shenghao YU Zhansen QIAN 《Chinese Journal of Aeronautics》 2025年第4期7-9,共3页
Due to the coexistence of compressibility,viscosity,and threedimensional effects,laminar flow is difficult to maintain for high-speed boundary layer on complex geometries.The unstable disturbance waves in the boundary... Due to the coexistence of compressibility,viscosity,and threedimensional effects,laminar flow is difficult to maintain for high-speed boundary layer on complex geometries.The unstable disturbance waves in the boundary layer are excited and rapidly increase during the receptivity process,so sufficiently large Reynolds stress causes the basic flow velocity profile to change,and the formation of turbulence is inevitable. 展开更多
关键词 high speed boundary layer large reynolds stress transition control surface microstructure unstable disturbance waves CHALLENGES suggestions boundary layer
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Idle speed control of proton exchange membrane fuel cell system via extended Kalman filter observer
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作者 ZHAO Hong-hui DING Tian-wei +4 位作者 WANG Yi-lin HUANG Xing DU Jing HAO Zhi-qiang MIN Hai-tao 《控制理论与应用》 北大核心 2025年第8期1615-1624,共10页
When the proton exchange membrane fuel cell(PEMFC)system is running,there will be a condition that does not require power output for a short time.In order to achieve zero power output under low power consumption,it is... When the proton exchange membrane fuel cell(PEMFC)system is running,there will be a condition that does not require power output for a short time.In order to achieve zero power output under low power consumption,it is necessary to consider the diversity of control targets and the complexity of dynamic models,which brings the challenge of high-precision tracking control of the stack output power and cathode intake flow.For system idle speed control,a modelbased nonlinear control framework is constructed in this paper.Firstly,the nonlinear dynamic model of output power and cathode intake flow is derived.Secondly,a control scheme combining nonlinear extended Kalman filter observer and state feedback controller is designed.Finally,the control scheme is verified on the PEMFC experimental platform and compared with the proportion-integration-differentiation(PID)controller.The experimental results show that the control strategy proposed in this paper can realize the idle speed control of the fuel cell system and achieve the purpose of zero power output.Compared with PID controller,it has faster response speed and better system dynamics. 展开更多
关键词 proton exchange membrane fuel cell idle speed control zero power output output power nonlinear model extended Kalman filter observer
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Method Design and Field Experiment Validation of Predictive Fuel-saving Cruise Control Based on Cloud Control Platform
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作者 Keke Wan Shuyan Li +2 位作者 Bolin Gao Fachao Jiang Yanbin Liu 《Chinese Journal of Mechanical Engineering》 2025年第5期297-316,共20页
Predictive cruise control(PCC)is an intelligence-assisted control technology that can significantly improve the overall performance of a vehicle by using road and traffic information in advance.With the continuous dev... Predictive cruise control(PCC)is an intelligence-assisted control technology that can significantly improve the overall performance of a vehicle by using road and traffic information in advance.With the continuous development of cloud control platforms(CCPs)and telematics boxes(T-boxes),cloud-based predictive cruise control(CPCC)systems are considered an effective solution to the problems of map update difficulties and insufficient computing power on the vehicle side.In this study,a vehicle-cloud hierarchical control architecture for PCC is designed based on a CCP and T-box.This architecture utilizes waypoint structures for hierarchical and dynamic cooperative inter-triggering,enabling rolling optimization of the system and commending parsing at the vehicle end.This approach significantly improves the anti-interference capability and resolution efficiency of the system.On the CCP side,a predictive fuel-saving speed-planning(PFSP)algorithm that considers the throttle input,speed variations,and time efficiency based on the waypoint structure is proposed.It features a forward optimization search without requiring weight adjustments,demonstrating robust applicability to various road conditions and vehicles equiped with constant cruise(CC)system.On the vehicle-side T-box,based on the reference control sequence with the global navigation satellite system position,the recommended speed is analyzed and controlled using the acute angle principle.Through analyzing the differences of the PFSP algorithm compared to dynamic programming(DP)and Model predictive control(MPC)algorithms under uphill and downhill conditions,the results show that the PFSP achieves good energy-saving performance compared to CC without exhibiting significant speed fluctuations,demonstrating strong adaptability to the CC system.Finally,by building an experimental platform and running field tests over a total of 2000 km,we verified the effectiveness and stability of the CPCC system and proved the fuel-saving performance of the proposed PFSP algorithm.The results showed that the CPCC system equipped with the PFSP algorithm achieved an average fuel-saving rate of 2.05%-4.39%compared to CC. 展开更多
关键词 Predictive cruise control Cloud control platform Hierarchical control architecture Fuel-saving speed planning
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Enhanced interconnection and damping assignment passivity-based control for PM synchronous motors
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作者 Mohamed Azzi Lotfi Baghli +2 位作者 Ehsan Jamshidpour Phatiphat Thounthong Noureddine Takorabet 《Global Energy Interconnection》 2025年第4期657-667,共11页
Permanent Magnet Synchronous Motors(PMSMs)are widely employed in high-performance drive applications due to their superior efficiency and dynamic capabilities.However,their control remains challenging owing to nonline... Permanent Magnet Synchronous Motors(PMSMs)are widely employed in high-performance drive applications due to their superior efficiency and dynamic capabilities.However,their control remains challenging owing to nonlinear dynamics,parameter variations,and unmeasurable external disturbances,particularly load torquefluctuations.This study proposes an enhanced Interconnection and Damp-ing Assignment Passivity-Based Control(IDA-PBC)scheme,formulated within the port-controlled Hamiltonian(PCH)framework,to address these limitations.A nonlinear disturbance observer is embedded to estimate and compensate,in real time,for lumped mis-matched disturbances arising from parameter uncertainties and external loads.Additionally,aflatness-based control strategy is employed to generate the desired current references within the nonlinear drive system,ensuring accurate tracking of time-varying speed commands.This integrated approach preserves the system’s energy-based structure,enabling systematic stability analysis while enhancing robustness.The proposed control architecture also maintains low complexity with a limited number of tunable parameters,facilitating practical implementation.Simulation and experimental results under various operating conditions demonstrate the effectiveness and robustness of the proposed method.Comparative analysis with conventional proportional-integral(PI)control and standard IDA-PBC strategies confirms its capability to handle disturbances and maintain dynamic performance. 展开更多
关键词 Hamiltonian energy control Interconnection and damping assignment passivity-based control IDA-PBC Motor drives Permanent-magnet synchronous machine(PMSM) Speed control
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Aerodynamic/control coupling optimization of reentry vehicle under wide speed range
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作者 Lulu Jiang Chao Dong +1 位作者 Xin Pan Gang Chen 《Acta Mechanica Sinica》 2025年第5期65-78,共14页
The high-speed reentry vehicle operates across a broad range of speeds and spatial domains,where optimal aerodynamic shapes for different speeds are contradictory.This makes it challenging for a single-Mach optimizati... The high-speed reentry vehicle operates across a broad range of speeds and spatial domains,where optimal aerodynamic shapes for different speeds are contradictory.This makes it challenging for a single-Mach optimization design to meet aerodynamic performance requirements throughout the vehicle’s flight envelope.Additionally,the strong coupling between aerodynamics and control adds complexity,as fluctuations in aerodynamic parameters due to speed variations complicate control system design.To address these challenges,this study proposes an aerodynamic/control coupling optimization design approach.This method,based on aerodynamic optimization principles,incorporates active control technology,treating aerodynamic layout and control system design as primary components during the conceptual design phase.By integrating the design and evaluation of aerodynamics and control,the approach aims to reduce design iterations and enhance overall flight performance.The comprehensive design of the rotary reentry vehicle,using this optimization strategy,effectively balances performance at supersonic and hypersonic speeds.The results show that the integrated design model meets aerodynamic and control performance requirements over a broader range of Mach numbers,preventing performance degradation due to deviations from the design Mach number,and providing a practical solution for high-speed reentry vehicle design. 展开更多
关键词 Aerodynamic/control coupling Surrogate-based optimization High-speed vehicle Wide speed range HYPERSONIC
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A new fixed-depth suspension control algorithm for mobile marine seismometer and its testing results
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作者 Fei Hou Jiabiao Li +2 位作者 Xinke Zhu Weiwei Ding Zhiteng Yu 《Acta Oceanologica Sinica》 2025年第2期91-103,共13页
A mobile marine seismometer(MMS)is a vertical underwater vehicle that detects ocean seismic waves.One of the critical operational requirements for an MMS is that it remains suspended at a desired depth.This article ai... A mobile marine seismometer(MMS)is a vertical underwater vehicle that detects ocean seismic waves.One of the critical operational requirements for an MMS is that it remains suspended at a desired depth.This article aimed to propose a fixed-depth suspension control for the MMS with a limited onboard energy supply.The research team established a kinematic model to analyze fluctuations in the vertical motion of the MMS and the delayed response of the system.We ascertained a direct one-to-one correlation between the displacement volume of the mobile ocean seismic instrument and the depth at which it reaches a state of neutral buoyancy(commonly referred to as the hover depth).A fixed-depth control algorithm was introduced,allowing a gradual approach to the necessary displacement volume to reach the desired suspension depth.The study optimized the boundary conditions to reduce unnecessary adjustments and mitigate the time delay caused by the instrument’s inertia,thereby significantly minimizing energy consumption.This method does not require calculating the hydrodynamic parameters or transfer functions of the MMS,thereby considerably reducing the implementation complexity.In the three-month sea trial in the South China Sea,the seismic instrument was set to hover at 800 m,with a permissible fluctuation of±100 m,operating on a seven-day cycle.The experimental results show that the seismic instrument has an average hover error of 34.6 m,with a vertical drift depth of 29.6 m per cycle,and the buoyancy adjustment system made six adjustments,indicating that our proposed control method performs satisfactorily.In addition,this method provides new insights for the fixed-depth control of other ocean observation devices that rely on buoyancy adjustment. 展开更多
关键词 mobile marine seismometer fixed-depth control algorithm low buoyancy-adjustment cost faster convergence speed
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Autonomous Navigation Algorithm for Underactuated Unmanned Surface Vehicle Based on Model Predictive Control
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作者 CHEN Guoquan LI Yuqin +1 位作者 HUANG Zike YANG Shenhua 《Journal of Shanghai Jiaotong university(Science)》 2025年第6期1255-1264,共10页
To achieve the track following and collision avoidance of underactuated unmanned surface vehicle(USV),autonomous navigation model based on model predictive control is established by including the track offset,speed va... To achieve the track following and collision avoidance of underactuated unmanned surface vehicle(USV),autonomous navigation model based on model predictive control is established by including the track offset,speed variation and rule compliance as the evaluation functions and including the ship domain of dynamic/static navigation obstacles and the mechanical characteristics limitation as constraints.The effectiveness of the model for autonomous navigation of USV in the situation of multi-ship encounters and in the complex waters with both dynamic and static obstructions is verified by several groups of simulation work.The simulation results show that the proposed model can realize the autonomous navigation of the underactuated USV under the complex waters. 展开更多
关键词 underactuated unmanned surface vehicle(USV) model predictive control track offset speed variation rule compliance
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Optimizing risk management for post-amputation wound complications in diabetic patients: Focus on glycemic and immunosuppressive control
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作者 Zhi-Peng Li Jin-Ke Sun +1 位作者 Wei-Ping Fu Chang-Jiang Zhang 《World Journal of Diabetes》 2025年第3期277-283,共7页
This study highlights the importance of identifying and addressing risk factors associated with wound complications following transtibial amputation in diabetic patients.These amputations,often necessitated by severe ... This study highlights the importance of identifying and addressing risk factors associated with wound complications following transtibial amputation in diabetic patients.These amputations,often necessitated by severe diabetic foot ulcers,carry significant risks of postoperative complications such as infection and delayed wound healing.Elevated hemoglobin A1c levels,indicative of poor glycemic control,and a history of kidney transplantation,due to required immunosuppressive therapy,are key factors influencing these outcomes.This paper emphasizes the need for enhanced glycemic management and personalized postoperative care,particularly for immunocompromised individuals,to minimize complications and improve patient prognosis.Future research should focus on prospective studies to validate targeted interventions and optimize care strategies,ultimately aiming to reduce the healthcare burden associated with diabetic foot complications. 展开更多
关键词 Transtibial amputation Diabetic foot Wound complications Risk factors Glycemic control Hemoglobin A1c Immunosuppressive therapy Kidney transplantation Personalized care Postoperative outcomes
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Osteocytic vinculin controls bone mass by modulating Mef2c-driven sclerostin expression in mice
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作者 Yishu Wang Jianmei Huang +7 位作者 Sixiong Lin Lei Qin Dingyu Hao Peijun Zhang Shaochuan Huo Xuenong Zou Di Chen Guozhi Xiao 《Bone Research》 2025年第5期1282-1294,共13页
The focal adhesion(FA)is the structural basis of the cell-extracellular matrix crosstalk and plays important roles in control of organ formation and function.Here we show that expression of FA protein vinculin is dram... The focal adhesion(FA)is the structural basis of the cell-extracellular matrix crosstalk and plays important roles in control of organ formation and function.Here we show that expression of FA protein vinculin is dramatically reduced in osteocytes in patients with aging-related osteoporosis.Vinculin loss severely impaired osteocyte adhesion and dendrite formation.Deleting vinculin using the mouse 10-kb Dmp1-Cre transgenic mice causes dramatic bone loss in the weight-bearing long bones and spine,but not in the skull,in both young and aged mice by impairing osteoblast formation and function without markedly affecting bone resorption.Vinculin loss impairs the anabolic response of skeleton to mechanical loading in mice.Vinculin knockdown increases,while vinculin overexpression decreases,sclerostin expression in osteocytes without impacting expression of Mef2c,a major transcriptional regulator of the Sost gene,which encodes sclerostin.Vinculin interacts with Mef2c and retains the latter in the cytoplasm.Thus,vinculin loss enhances Mef2c nuclear translocation and binding to the Sost enhancer ECR5 to promote sclerostin expression in osteocytes and reduces bone formation.Consistent with this notion,deleting Sost expression in osteocytes reverses the osteopenic phenotypes caused by vinculin loss in mice.Finally,we find that estrogen is a novel regulator of vinculin expression in osteocytes and that vinculin-deficient mice are resistant to ovariectomy-induced bone loss.Thus,we demonstrate a novel mechanism through which vinculin inhibits the Mef2c-driven sclerostin expression in osteocytes to promote bone formation. 展开更多
关键词 focal adhesion fa mef c driven sclerostin expression aging related osteoporosis osteocytic vinculin osteocyte adhesion bone loss control organ formation functionhere focal adhesion
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基于VSD-MPC的主动悬架预瞄控制策略
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作者 赵健 周文博 +5 位作者 王月 朱冰 陈志成 韩嘉懿 张培兴 宋东鉴 《汽车工程》 北大核心 2026年第1期146-155,共10页
针对主动悬架预瞄控制策略对车速适应性弱的问题,提出一种基于变速离散模型预测控制(variable speed discrete-model predictive control,VSD-MPC)的主动悬架预瞄控制策略。首先,通过时域转换方法设计一种车速自适应路面高程信息采样机... 针对主动悬架预瞄控制策略对车速适应性弱的问题,提出一种基于变速离散模型预测控制(variable speed discrete-model predictive control,VSD-MPC)的主动悬架预瞄控制策略。首先,通过时域转换方法设计一种车速自适应路面高程信息采样机制,匹配不同车速下主动悬架对控制周期内所需路面信息的变化需求。其次,提出一种VSD-MPC方法用于主动悬架预瞄控制。利用拉盖尔函数将传统MPC中二次规划求解最优控制序列的过程替代为拟合求导环节,降低算力需求。仿真测试结果表明,本文设计的主动悬架预瞄控制策略不仅能够在不同的车速下使车辆的垂向性能至少提升39.4%,同时可以将算力降低50%以上。 展开更多
关键词 车辆工程 主动悬架 预瞄控制 车速自适应 模型预测控制
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基于改进自抗扰控制的艾草收获滚筒转速稳定控制研究
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作者 李奕 张开 +1 位作者 陈俊男 胡新宇 《液压与气动》 北大核心 2026年第1期73-85,共13页
为解决艾草收获机弹齿滚筒在作业过程中因负载扰动引起的转速不稳定问题,提出了一种基于改进自抗扰控制的滚筒转速稳定控制策略。建立了滚筒负载数学模型,分析了负载扰动对液压系统动态特性的影响规律。为提高比例阀在复杂工况下的响应... 为解决艾草收获机弹齿滚筒在作业过程中因负载扰动引起的转速不稳定问题,提出了一种基于改进自抗扰控制的滚筒转速稳定控制策略。建立了滚筒负载数学模型,分析了负载扰动对液压系统动态特性的影响规律。为提高比例阀在复杂工况下的响应平滑性与抗扰能力,在传统自抗扰控制算法的扩张状态观测器中引入平滑非线性函数shfal,改善了原fal函数在原点处的不光滑性,实现了对扰动的连续估计与补偿。通过AMESim-MATLAB联合仿真验证,改进自抗扰控制策略,在稳态、正弦及突变负载条件下均具有较快的响应速度、更高的稳态精度和更强的抗扰性能。田间试验进一步表明,该控制策略能够显著改善脱叶效果,提高脱净率,降低含杂率与破损率,验证了其在实际作业条件下的工程可用性。研究表明,该方法能有效抑制滚筒转速波动,提升系统稳定性与作业质量,为艾草收获机液压控制系统的优化设计提供了可行方案与理论依据。 展开更多
关键词 艾草收获 转速控制 液压系统 自抗扰控制
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近接软土基坑高铁桥梁变形注浆主动控制研究
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作者 孙红林 涂启柱 +2 位作者 孟长江 陈占 陈侃 《铁道工程学报》 北大核心 2026年第2期18-24,36,共8页
研究目的:对于近接软土基坑高铁桥梁变形控制问题,现有研究主要集中于加强围护结构、加固坑内土体、分区开挖、设置隔离桩等被动控制措施,很难实现2~3 mm级的变形控制要求,且会造成工程造价和工期显著增加。近年来在近接软土基坑地铁盾... 研究目的:对于近接软土基坑高铁桥梁变形控制问题,现有研究主要集中于加强围护结构、加固坑内土体、分区开挖、设置隔离桩等被动控制措施,很难实现2~3 mm级的变形控制要求,且会造成工程造价和工期显著增加。近年来在近接软土基坑地铁盾构隧道方面开展了系列如注浆等变形主动控制研究,但在近接软土基坑高铁桥梁变形主动控制方面鲜有涉及。本文以某邻近高铁桥梁软土深基坑工程为依托,开展注浆主动控制高铁桥梁水平变形规律、控制参数及现场应用研究。研究结论:(1)数值分析和监测数据表明,通过加强基坑支护措施虽能严格控制围护结构变形,但很难满足邻近高铁桥梁毫米级变形控制要求;(2)通过现场试验与数值分析得出双孔同步对称注浆规律如下:随着注浆量增加,高铁桥墩水平变形逐渐增加,二者基本呈正比关系;随着注浆孔与桥墩距离减小,桥墩水平变形逐渐增加,且增加速率逐渐增大;随着注浆深度增加,桥墩水平变形逐渐增加,但增大速率逐渐趋缓;(3)现场应用表明单组双孔对称同步注浆能够减小高铁桥墩水平变形0.7~1.3 mm,通过多次双孔对称同步注浆能够适时、主动控制高铁桥墩变形满足控制要求;(4)本研究结果可为近接高铁桥梁软土基坑变形控制提供参考和借鉴。 展开更多
关键词 高铁桥梁 软土基坑 主动控制措施 双孔同步对称注浆
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考虑参数慢时变的泵马达系统变速恒频控制研究
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作者 陈文婷 王文龙 +3 位作者 张震 艾超 张珈瑞 杜泽莉 《机械工程学报》 北大核心 2026年第2期455-470,共16页
针对泵马达变速恒频系统在液压系统参数慢时变和外部参数扰动下的控制难题,提出一种结合反馈线性化与径向基函数(Radial basis function,RBF)神经网络自适应的复合控制策略。首先,建立泵马达系统的非线性数学模型,通过反馈线性化理论处... 针对泵马达变速恒频系统在液压系统参数慢时变和外部参数扰动下的控制难题,提出一种结合反馈线性化与径向基函数(Radial basis function,RBF)神经网络自适应的复合控制策略。首先,建立泵马达系统的非线性数学模型,通过反馈线性化理论处理系统非线性特性,将其转化为线性形式;其次,利用RBF神经网络在线逼近系统中的未知函数项,并设计自适应算法实时调整神经网络权值矩阵及控制参数,以应对参数慢时变特性。将研究的泵马达闭式变速恒频系统应用于风力发电场景,仿真结果表明,在外部风速扰动和内部参数变化的共同作用下,该控制策略能够有效维持变量马达转速在并网国家标准(1500±6)r/min范围内,保证风电机组顺利并网。最后,通过搭建24 kW液压型风电机组半物理仿真试验平台,对所提出的变速恒频控制策略进行了试验验证。试验结果进一步证实了理论分析和仿真研究的正确性,即所研究的控制策略在实际应用中具有良好的抗扰动性能和控制精度,为发电装备中的泵马达变速恒频系统的稳定、精准运行和高效能量捕获提供了有力的技术支撑。 展开更多
关键词 泵马达系统 变速恒频控制 参数慢时变 反馈线性化 径向基函数神经网络 自适应控制
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一种新型管道内检测器泄流调速装置的数值模拟分析
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作者 唐建 余文秀 +2 位作者 张秋平 焦向东 丁学鹏 《上海交通大学学报》 北大核心 2026年第2期319-330,共12页
针对输油管道内检测器运行速度控制问题,提出了一种新型的泄流调速装置,该装置由泄流阀座、泄流阀芯、弹簧、导杆等组成.通过分析检测器泄流调速装置在水平管道内的受力情况,建立了泄流调速装置的数学模型.利用数值模拟的方法研究了泄... 针对输油管道内检测器运行速度控制问题,提出了一种新型的泄流调速装置,该装置由泄流阀座、泄流阀芯、弹簧、导杆等组成.通过分析检测器泄流调速装置在水平管道内的受力情况,建立了泄流调速装置的数学模型.利用数值模拟的方法研究了泄流阀座弧度、泄流阀芯-检测器后端距离以及入口流体速度对管道内检测器运动状态的影响.研究结果表明,在相同边界条件下,流体介质通过检测器时,泄流调速装置前后两端压差、总水头损失系数、流场的湍流动能值与泄流阀座左侧弧度成反比关系,而与右侧弧度成正比关系,当泄流阀座左侧弧度为60°、右侧弧度为15°时,各参数均为最小值;入口流体速度的增加会导致泄流调速装置前后两端压差、流场湍流动能值增大,当泄流阀座弧度相同、入口流体速度从0.6 m/s增加到2 m/s时,压差增加了106290 Pa,湍流动能增加了1.831 m^(2)/s 2;泄流阀芯-检测器后端距离与泄流调速装置前后两端压差、检测器速度成反比关系,当阀芯-检测器后端距离从15 mm增加到35 mm时,泄流调速装置前后两端的压差减小了240 Pa.本研究为优化输油管道内检测器的运行性能、提高检测效率提供了重要的理论基础与实践指导. 展开更多
关键词 输油管道 内检测器 泄流调速装置 压差 速度控制
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涡流发生器对动车组气动减阻的研究
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作者 崔洪江 吴博威 +1 位作者 樊伟航 关颖 《铁道学报》 北大核心 2026年第2期31-39,共9页
为了降低列车高速运行受到的气动阻力,选择尾车3个典型安装位置,包括流线型过渡位置、边界层突变处和尾车压力突变处。采用基于SST k-ω湍流模型的雷诺时均法研究高速列车尾车安装涡流发生器对尾部流动特征以及列车气动载荷的影响。结... 为了降低列车高速运行受到的气动阻力,选择尾车3个典型安装位置,包括流线型过渡位置、边界层突变处和尾车压力突变处。采用基于SST k-ω湍流模型的雷诺时均法研究高速列车尾车安装涡流发生器对尾部流动特征以及列车气动载荷的影响。结果表明:涡流发生器能显著改变尾车周围的流场,产生一对与原涡流旋向相反的涡流结构,降低尾流涡强度和范围。在尾车安装涡流发生器后,气流流动受到涡流发生器的阻碍产生积聚,从而在尾车表面形成正压区域,降低压差阻力;当涡流发生器布置在尾车压力突变处时,阻力显著降低,尾车阻力降低16.8%,整车阻力降低6.82%。研究结果为动车组气动减阻提供了新的思路,对突破传统气动减阻技术的局限性具有重要意义。 展开更多
关键词 动车组 流动控制 涡流发生器 气动减阻 压差阻力
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高速平面机械臂柔性末端残余振动主动控制方法
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作者 李华 蒋勉 +2 位作者 谢凌波 何宽芳 徐震 《噪声与振动控制》 北大核心 2026年第1期68-75,共8页
高速运行的机械臂会对其机械结构产生强烈冲击,尤其加速度与减速度的突变导致在其柔性末端产生较大的残余振动,从而影响机械臂的运动和定位精度。为有效抑制平面机械臂柔性末端残余振动,避免控制系统高度依赖机械臂精确模态参数,主要研... 高速运行的机械臂会对其机械结构产生强烈冲击,尤其加速度与减速度的突变导致在其柔性末端产生较大的残余振动,从而影响机械臂的运动和定位精度。为有效抑制平面机械臂柔性末端残余振动,避免控制系统高度依赖机械臂精确模态参数,主要研究高速平面机械臂柔性末端残余振动主动控制方法。首先对平面机械臂进行有限元分析获取振型和频率,其次建立平面机械臂运动学模型并对运动轨迹进行开环平滑速度规划,最后以加速度为反馈信号实现闭环残余振动控制。考虑由滤波、加速度-位移相位差及传输等因素引起的残余振动加速度信号相位滞后,进一步采用相移技术,通过加速度相移补偿和模糊反馈控制,进行残余振动控制研究与实验验证。实验结果表明,开环速度规划算法使速度具有良好的平滑性,对残余振动有一定抑制能力;闭环加速度反馈控制算法采用合适超前时间和模糊反馈增益,能达到更好的高速机械臂残余振动控制效果。 展开更多
关键词 振动与波 高速平面机械臂 残余振动 速度规划 加速度反馈 模糊反馈控制
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一种电子增材制造喷墨打印精度的协同控制方法
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作者 刘清涛 于攀宇 +3 位作者 郭炯棋 尹恩怀 杨鹏涛 吕景祥 《华南理工大学学报(自然科学版)》 北大核心 2026年第1期94-103,共10页
电子增材制造技术在高精度微电子制造中具有重要的应用价值,但打印速度波动导致的墨滴落点低精度问题一直制约着打印质量的提升。鉴于此,该文提出了基于LinuxCNC的S型速度规划+恒间距喷射(SSP-FDI)协同控制策略,通过将传统数控系统速度... 电子增材制造技术在高精度微电子制造中具有重要的应用价值,但打印速度波动导致的墨滴落点低精度问题一直制约着打印质量的提升。鉴于此,该文提出了基于LinuxCNC的S型速度规划+恒间距喷射(SSP-FDI)协同控制策略,通过将传统数控系统速度算法优化为S型速度控制算法来有效降低运动冲击,采用恒间距触发模式来实现墨滴间距的精确控制,削弱速度波动对落点精度的影响。作者还自主搭建了一套集成五轴运动控制与电子喷墨打印的实验平台,开发了相应的控制系统,设计了多角度折线以及电极对比实验。结果表明:相较于传统的梯形速度规划+固定频率喷射控制策略,SSP-FDI协同控制策略可显著降低墨滴落点的精度误差;在基板温度为100°C、20 mm×20 mm的矩形电极打印实验中,补偿后的电极表面最大粗糙度降低至6μm;在5组不同的基板温度下,样件表面粗糙度平均降幅达18.79%,电阻率平均降幅达18.70%。该文提出的基于LinuxCNC的协同控制策略能有效提升复杂轨迹下的打印质量,为高精度电子器件增材制造提供了一种新的解决方案。 展开更多
关键词 电子增材制造 打印精度 LinuxCNC系统 速度控制算法 协同控制
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