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Optimization Control of Multi-Mode Coupling All-Wheel Drive System for Hybrid Vehicle
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作者 Lipeng Zhang Zijian Wang +1 位作者 Liandong Wang Changan Ren 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期340-355,共16页
The all-wheel drive(AWD)hybrid system is a research focus on high-performance new energy vehicles that can meet the demands of dynamic performance and passing ability.Simultaneous optimization of the power and economy... The all-wheel drive(AWD)hybrid system is a research focus on high-performance new energy vehicles that can meet the demands of dynamic performance and passing ability.Simultaneous optimization of the power and economy of hybrid vehicles becomes an issue.A unique multi-mode coupling(MMC)AWD hybrid system is presented to realize the distributed and centralized driving of the front and rear axles to achieve vectored distribution and full utilization of the system power between the axles of vehicles.Based on the parameters of the benchmarking model of a hybrid vehicle,the best model-predictive control-based energy management strategy is proposed.First,the drive system model was built after the analysis of the MMC-AWD’s drive modes.Next,three fundamental strategies were established to address power distribution adjustment and battery SOC maintenance when the SOC changed,which was followed by the design of a road driving force observer.Then,the energy consumption rate in the average time domain was processed before designing the minimum fuel consumption controller based on the equivalent fuel consumption coefficient.Finally,the advantage of the MMC-AWD was confirmed by comparison with the dynamic performance and economy of the BYD Song PLUS DMI-AWD.The findings indicate that,in comparison to the comparative hybrid system at road adhesion coefficients of 0.8 and 0.6,the MMC-AWD’s capacity to accelerate increases by 5.26%and 7.92%,respectively.When the road adhesion coefficient is 0.8,0.6,and 0.4,the maximum climbing ability increases by 14.22%,12.88%,and 4.55%,respectively.As a result,the dynamic performance is greatly enhanced,and the fuel savings rate per 100 km of mileage reaches 12.06%,which is also very economical.The proposed control strategies for the new hybrid AWD vehicle can optimize the power and economy simultaneously. 展开更多
关键词 Hybrid vehicle All-wheel drive multi-mode coupling Energy management model predictive control
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Trajectory tracking of powered parafoil based on characteristic model based all-coefficient adaptive control 被引量:2
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作者 TAN Pan-long SUN Qing-lin +3 位作者 JIANG Yu-xin ZHU Er-lin CHEN Zeng-qiang HE Ying-ping 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第5期1073-1081,共9页
One of the primary difficulties in using powered parafoil(PPF) systems is the lack of effective trajectory tracking controllers since the trajectory tracking control is the essential operation for PPF to accomplish au... One of the primary difficulties in using powered parafoil(PPF) systems is the lack of effective trajectory tracking controllers since the trajectory tracking control is the essential operation for PPF to accomplish autonomous tasks. The characteristic model(CM) based all-coefficient adaptive control(ACAC) designed for PPF systems in horizontal and vertical trajectory control is proposed. The method is easy to use and convenient to adjust and test. Just a few parameters are adapted during the control process. In application, vertical and horizontal CMs are designed and ACAC controllers are constructed to control vertical altitude and horizontal trajectory of PPF based on the proposed CMs, respectively. Result analysis of different simulations shows that the applied ACAC control method is effective for trajectory tracking of the PPF systems and the approach guarantees the transient performance of the PPF systems with better disturbance rejection ability. 展开更多
关键词 powered PARAFOIL (PPF) characteristic model (CM) all-coefficient adaptive control (ACAC) TRAJECTORY tracking
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Characteristic Model-based Discrete-time Sliding Mode Control for Spacecraft with Variable Tilt of Flexible Structures 被引量:5
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作者 Lei Chen Yan Yan +1 位作者 Chaoxu Mu Changyin Sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第1期42-50,共9页
In this paper, the finite-time attitude tracking control problem for the spacecrafts with variable tilt of flexible appendages in the conditions of exogenous disturbances and inertia uncertainties is addressed. First ... In this paper, the finite-time attitude tracking control problem for the spacecrafts with variable tilt of flexible appendages in the conditions of exogenous disturbances and inertia uncertainties is addressed. First the characteristic modeling method is applied to the problem of the spacecraft modeling. Second, a novel adaptive sliding mode surface is designed based on the characteristic model. Furthermore, a discrete-time sliding mode control (DTSMC) law, which makes the tracking error converge into a predefined bound in finite time, is proposed by employing the parameters of characteristic model associated with the sliding mode surface to provide better performances, robustness, faster response, and higher control precision. The designed DTSMC includes the adaptive control architecture and is chattering-free. Finally, digital simulations of a sun synchronous orbit satellite (SSOS) are presented to illustrate effectiveness of the control strategies as well as to verify the practical feasibility of the rapid maneuver mission. © 2014 Chinese Association of Automation. 展开更多
关键词 Flexible structures NAVIGATION ORBITS SPACECRAFT
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Trajectory tracking control of characteristic model for nonplanar hex-rotor UAV
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作者 PENG Cheng QIAO Guanyu CAI Lihua 《High Technology Letters》 EI CAS 2022年第4期440-450,共11页
The nonplanar hex-rotor unmanned aerial vehicle(UAV)has much higher driving property,greater payload capacity and damage tolerance than quad-rotor UAV.It is difficult to design a highperformance controller of easy eng... The nonplanar hex-rotor unmanned aerial vehicle(UAV)has much higher driving property,greater payload capacity and damage tolerance than quad-rotor UAV.It is difficult to design a highperformance controller of easy engineering implementation for strongly coupled nonlinear hex-rotorUAV system.In response to this practical problem,an adaptive trajectory tracking control based oncharacteristic model for nonplanar hex-rotor is studied.Firstly,the dynamic model for the hex-rotorUAV is devised.Secondly,according to dynamic characteristics,environmental characteristics andcontrol performance requirements,the characteristic model of the hex-rotor UAV is constructed.Then,based on the characteristic model,a golden section adaptive controller is designed to realizetrajectory tracking.Furthermore,the stability analysis of the closed loop hex-rotor system is given.Finally,the validity of the proposed trajectory tracking control method adopted in the nonplanar hex-rotor UAV is demonstrated via numerical simulations and hex-rotor prototype experiments. 展开更多
关键词 nonplanar hex-rotor unmanned aerial vehicle(UAV) characteristic model golden section adaptive controller stability analysis trajectory tracking control
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Geological characteristics and models of fault-foldfracture body in deep tight sandstone of the second member of Upper Triassic Xujiahe Formation in Xinchang structural belt of Sichuan Basin,SW China 被引量:1
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作者 LIU Junlong LIU Zhongqun +8 位作者 LIU Zhenfeng LIU Yali SHEN Baojian XIAO Kaihua BI Youyi WANG Xiaowen WANG Ail FAN Lingxiao LI Jitongl 《Petroleum Exploration and Development》 SCIE 2023年第3期603-614,共12页
In the second member of the Upper Triassic Xujiahe Formation(T_(3)x_(2))in the Xinchang area,western Sichuan Basin,only a low percent of reserves has been recovered,and the geological model of gas reservoir sweet spot... In the second member of the Upper Triassic Xujiahe Formation(T_(3)x_(2))in the Xinchang area,western Sichuan Basin,only a low percent of reserves has been recovered,and the geological model of gas reservoir sweet spot remains unclear.Based on a large number of core,field outcrop,test and logging-seismic data,the T_(3)x_(2) gas reservoir in the Xinchang area is examined.The concept of fault-fold-fracture body(FFFB)is proposed,and its types are recognized.The main factors controlling fracture development are identified,and the geological models of FFFB are established.FFFB refers to faults,folds and associated fractures reservoirs.According to the characteristics and genesis,FFFBs can be divided into three types:fault-fracture body,fold-fracture body,and fault-fold body.In the hanging wall of the fault,the closer to the fault,the more developed the effective fractures;the greater the fold amplitude and the closer to the fold hinge plane,the more developed the effective fractures.Two types of geological models of FFFB are established:fault-fold fracture,and matrix storage and permeability.The former can be divided into two subtypes:network fracture,and single structural fracture,and the later can be divided into three subtypes:bedding fracture,low permeability pore,and extremely low permeability pore.The process for evaluating favorable FFFB zones was formed to define favorable development targets and support the well deployment for purpose of high production.The study results provide a reference for the exploration and development of deep tight sandstone oil and gas reservoirs in China. 展开更多
关键词 fault-fold-fracture body fracture control factor genetic characteristics geological model deep layer tight sandstone Xinchang structural belt Upper Triassic Xujiahe Formation Sichuan Basin
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Performance analysis model for real-time Ethernet-based computer numerical control system 被引量:2
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作者 万加富 李迪 +1 位作者 涂钰青 张春华 《Journal of Central South University》 SCIE EI CAS 2011年第5期1545-1553,共9页
In order to optimize the embedded system implementation for Ethernet-based computer numerical control (CNC) system, it is very necessary to establish the performance analysis model and further adopt the codesign met... In order to optimize the embedded system implementation for Ethernet-based computer numerical control (CNC) system, it is very necessary to establish the performance analysis model and further adopt the codesign method from the control, communication and computing perspectives. On the basis of analyzing real-time Ethemet, system architecture, time characteristic parameters of control-loop ere, a performance analysis model for real-time Ethemet-based CNC system was proposed, which is able to include the timing effects caused by the implementation platform in the simulation. The key for establishing the model is accomplished by designing the error analysis module and the controller nodes. Under the restraint of CPU resource and communication bandwidth, the experiment with a case study was conducted, and the results show that if the deadline miss ratio of data packets is 0.2%, then the percentage error is 1.105%. The proposed model can be used at several stages of CNC system development. 展开更多
关键词 computer numerical control (CNC) system real-time Ethemet time characteristic parameters performance analysis model manufacturing accuracy
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Production characteristics and sweet-spots mapping of the Upper Devonian-Lower Mississippian Bakken Formation tight oil in southeastern Saskatchewan, Canada
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作者 CHEN Zhuoheng YANG Chao +4 位作者 JIANG Chunqing KOHLRUSS Dan HU Kezhen LIU Xiaojun YURKOWSKI Melinda 《Petroleum Exploration and Development》 2018年第4期662-672,共11页
A workflow that helps identify potential production sweet spots in the Middle Bakken tight oil play is proposed based on analysis of large amounts of production data. The proposed approach is a multivariate statistica... A workflow that helps identify potential production sweet spots in the Middle Bakken tight oil play is proposed based on analysis of large amounts of production data. The proposed approach is a multivariate statistical model that extracts relevant information from a training dataset of production wells to facilitate geological similarity comparison between economic and sub-economic production wells. The model is applied to the Middle Bakken tight oil play in southeastern Saskatchewan. Data screening for diagnostic geological indicators for sweet spots reveals that several geological factors indicative for conventional oil reservoirs seem to work for the Middle Bakken tight oil play as well. These factors include: a) the NE Torqunay-Rocanville Trend serving as a preferred regional migration path for connecting mature source rock in southern Williston Basin and the Middle Bakken tight reservoir in southeastern Saskatchewan; b) the oils in the Bakken tight reservoirs along the U.S. and Canada border are more likely from local matured Bakken source rocks; c) subtle structural components enhancing the convergence of dispersed hydrocarbons over a large area; d) top seal and lateral barrier improving preservation, thus favouring oil productivity; e) orientation of maximum horizontal stress coincident with the direction of the variogram spatial continuity in ultimate recoverable reserves, so the direction of horizontal well has a significant impact on the oil productivity. 展开更多
关键词 TIGHT OIL reservoir PRODUCTION characteristics multivariate statistical model PRODUCTION sweet-spot area geological controls Williston Basin Bakken FORMATION shale
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考虑电解槽能量流优化的电解铝负荷网荷互动可调容量评估
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作者 廖思阳 卞士琪 +2 位作者 徐箭 柯德平 孙元章 《中国电机工程学报》 北大核心 2025年第6期2110-2120,I0006,共12页
电解铝负荷是典型的热蓄能高耗能工业负荷,具备良好的调节能力,充分挖掘其调节潜力,量化电解铝负荷的可调容量使其灵活参与电网互动,能够有效缓解新能源消纳、弃风弃光等问题。首先,从生产工艺角度详细分析电解槽的能量平衡机制和附加... 电解铝负荷是典型的热蓄能高耗能工业负荷,具备良好的调节能力,充分挖掘其调节潜力,量化电解铝负荷的可调容量使其灵活参与电网互动,能够有效缓解新能源消纳、弃风弃光等问题。首先,从生产工艺角度详细分析电解槽的能量平衡机制和附加换热器的工作原理,建立电解槽的热输出控制模型。其次,基于电解槽的电热能量转换原理,由负荷的生产特性和调控约束得到负荷功率的调节边界,建立考虑电解槽能量流优化的可调容量评估模型。最后,通过模拟算例进行仿真,结果表明,通过加入附加换热器的工艺优化,使得铝厂在电解槽热平衡的能量输入和能量耗散方面均具有更强的可控性,电解铝负荷的功率调节能力得到明显提升,且功率调节的可持续时长也明显增加,显著增强了大容量电解铝参与新型电力系统网荷互动的适应性。 展开更多
关键词 电解铝负荷 能量平衡 换热器 热输出控制模型 可调容量评估
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柔直构网新能源送端系统故障响应特性计算方法 被引量:1
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作者 何佳伟 周博昊 +3 位作者 李斌 闫旭 李岩 曹润彬 《电力系统自动化》 北大核心 2025年第1期69-79,共11页
故障等值建模是系统级响应特性计算的基础。然而,现有研究较少涉及构网型换流器的故障等值建模。传统针对跟网型电力电子设备接入交流电网的短路电流计算方法,在柔直构网系统中容易出现结果失稳发散的问题。因此,文中考虑构网型柔直换... 故障等值建模是系统级响应特性计算的基础。然而,现有研究较少涉及构网型换流器的故障等值建模。传统针对跟网型电力电子设备接入交流电网的短路电流计算方法,在柔直构网系统中容易出现结果失稳发散的问题。因此,文中考虑构网型柔直换流器的电压-频率构网控制策略、主动降压策略以及跟网型新能源的低压穿越控制策略,建立了不同类型电力电子设备的故障等值模型。基于此,考虑不同电力电子设备电压源、电流源等值模型的频繁切换,提出了一种适用于柔直构网新能源送端系统的全网链式迭代故障响应特性计算方法,实现了短路电流计算的快速可靠收敛。基于PSCAD/EMTDC仿真平台,搭建了柔直构网新能源送端系统仿真模型,以进行多种故障类型和影响因素的大量仿真测试,充分验证了所提计算方法的可行性、精确性和优越性。 展开更多
关键词 柔直换流器 构网控制 故障等值模型 故障响应特性 链式迭代
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城市交通拥塞风险场级联失效及韧性评估研究
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作者 赵雪亭 胡立伟 周君 《交通运输系统工程与信息》 北大核心 2025年第2期146-156,共11页
应用信息物理系统,本文对城市交通拥塞风险场级联失效过程及量化评估韧性风险大小问题进行研究。首先,考虑城市交通拥塞风险的多维耦合特征,建立城市交通拥塞风险场真实交通路网和交通拥塞防控类型分区相互耦合的CPS(Cyber Physical Sys... 应用信息物理系统,本文对城市交通拥塞风险场级联失效过程及量化评估韧性风险大小问题进行研究。首先,考虑城市交通拥塞风险的多维耦合特征,建立城市交通拥塞风险场真实交通路网和交通拥塞防控类型分区相互耦合的CPS(Cyber Physical Systems)控制模型,运用复杂网络理论对交通域进行结构特性分析。其次,重新界定CPS特征参数,定义CPS级联失效4个过程,构建城市交通拥塞风险场CPS级联失效模型。然后,以风险因子为介入点,结合网络拓扑结构理论阐述风险扰动机理,通过归一定量化节点连通度、延误时间、平均运行速度和平均拥塞长度等韧性指标检验CPS连通性,采用不同失效-恢复策略,利用鲁棒性、破坏/恢复速率等指标评估CPS受损扰动及韧性恢复能力。案例结果显示:贵阳市城市交通拥塞风险场CPS真实交通网由170个交叉口和231条边构成,交通拥塞防控类型分区网络由21个交通指挥片区和41条边构成。CPS模型最大、最小度值分别为22、1,度值服从幂率分布函数,具备特有无标度网络特征,介数呈现指数分布;度值扰动对贵阳市真实交通路网影响程度最大,介数扰动使贵阳市交通拥塞防控类型分区影响最大。在t=2时刻,网络性能在介数扰动和度值扰动下网络性能均开始下降,介数扰动相较于度值扰动影响性能更大,均在t=7时达到最低。介数恢复效果均优于度值恢复,在介数扰动下,贵阳市真实交通路网的度值恢复和介数恢复效果均差,韧性值分别为0.01123和0.01252,显著低于交通拥塞防控类型分区的韧性值0.1355。综上,本文城市交通拥塞风险场韧性评估模型可有效实现定量化评价,对启动不同阶段交通拥塞控制策略有借鉴意义。 展开更多
关键词 城市交通 级联失效模型 风险扰动机理 交通拥塞风险 控制特性
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一种基于特征模型的永磁同步电机协调控制策略
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作者 陈瑞 吴悠 +1 位作者 杜荣华 唐宏宾 《电气工程学报》 北大核心 2025年第1期54-64,共11页
针对永磁同步电机应用于轨迹跟踪的协调控制问题,提出一种基于特征模型的协调控制策略。首先,通过二维坐标变换的方法对双轴运动系统进行了解耦,获得双轴运动系统的轮廓误差和切向误差。然后,利用特征模型方法,在每一轴位置环中设计一... 针对永磁同步电机应用于轨迹跟踪的协调控制问题,提出一种基于特征模型的协调控制策略。首先,通过二维坐标变换的方法对双轴运动系统进行了解耦,获得双轴运动系统的轮廓误差和切向误差。然后,利用特征模型方法,在每一轴位置环中设计一种不依赖于模型的黄金分割自适应控制器,同时采用一种逻辑微分控制器以保证系统的轮廓控制精度。针对所设计的控制方案进行了稳定性分析。最后选定两个参数差异较大的电机针对曲率变化大的螺旋线轨迹进行两种不同控制方案对比仿真,并且对结果进行数据分析。仿真结果表明,所设计的控制方案可以有效保证双轴运动系统的运行精度,该方案控制下的轮廓误差控制效果可以与基于PID控制器的轮廓误差控制效果相媲美,调试比PID控制方便、简单,可以节省大量时间成本,并为后续进一步研究永磁同步电机伺服系统在多轴协调控制中的应用奠定基础。 展开更多
关键词 永磁同步电机 特征模型 双轴运动系统 轮廓误差 协调控制
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大规模碱液电解制氢系统协调控制策略
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作者 李立民 申屠磊璇 +3 位作者 夏杨红 冯启帆 曹莹 韦巍 《洁净煤技术》 北大核心 2025年第3期83-94,共12页
在制氢基地中,多台并联的碱液电解槽协调控制共同参与可再生能源的调节是一种未来的主要趋势。然而,随时间变化的可再生能源会对碱液电解槽的温度产生影响,进而导致其额定功率发生变化。在这种情况下,如果持续使用具有恒定下垂系数的下... 在制氢基地中,多台并联的碱液电解槽协调控制共同参与可再生能源的调节是一种未来的主要趋势。然而,随时间变化的可再生能源会对碱液电解槽的温度产生影响,进而导致其额定功率发生变化。在这种情况下,如果持续使用具有恒定下垂系数的下垂控制器,可能会导致碱液电解槽之间出现不合理的功率分配。在现有研究中,这一问题很少被考虑到。为解决这一问题,针对含多台并联碱液电解槽的电解制氢系统提出了一种自适应功率协调控制方法。首先,建立了碱液电解槽的等效电路模型,并绘制出最大电流-温度曲线。在此基础上,提出了温度驱动的下垂系数设置策略。控制系统会定期更新碱液电解槽的模型,并结合其温度实时计算下垂系数。然后,分析了所提控制策略对碱液电解槽热力学特性的影响。最后,在所搭建的电解制氢试验平台上对所提控制策略进行了验证。试验结果表明,所提方法能够实现不同碱液电解槽之间合理的功率分配。 展开更多
关键词 多台并联的碱液电解槽 自适应功率协同控制策略 等效电路模型 温度驱动 热力学特性
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基于正交试验的气水喷嘴雾滴粒径预测数学模型
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作者 王鑫 李文璞 +3 位作者 邵和 郑沂怡 高玉荣 陈曦 《煤矿安全》 北大核心 2025年第1期72-78,共7页
为了解内混式气水喷嘴过程参数和结构参数对雾化特性的影响,基于自行设计的喷雾特性试验平台,使用正交试验方法定量分析了供气压力、供水压力、气水汇合角度、混合腔长度、出口尺寸对雾化特性的影响,在此基础上使用多元非线性回归方法... 为了解内混式气水喷嘴过程参数和结构参数对雾化特性的影响,基于自行设计的喷雾特性试验平台,使用正交试验方法定量分析了供气压力、供水压力、气水汇合角度、混合腔长度、出口尺寸对雾化特性的影响,在此基础上使用多元非线性回归方法建立喷嘴雾滴索特平均直径预测模型。试验结果表明:气流量随着供气压力、气水汇合角度、出口尺寸的增大而增大,随着供水压力的增大而减小;水流量随着供水压力、出口尺寸的增大而增大,随着供气压力、汇合角度的增大而减小;混合腔长度的变化对气水流量的影响不显著;索特平均直径随着供水压力、出口尺寸的增大而增大,随着供气压力、汇合角度、混合腔长度的增大而减小,各参数对喷嘴雾滴粒径影响的重要度排序依次为出口尺寸>供气压力>供水压力>气水汇合角度>混合腔长度;建立的多元非线性预测模型的计算值与试验结果变化趋势一致,平均相对误差为8.0%,可用于预测气水喷嘴的液滴尺寸。 展开更多
关键词 气水喷嘴 结构参数 流量特性 雾滴粒径 数学模型 粉尘防治
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我国幼儿自我控制的类型、发展特点及其教育建议——基于潜在剖面分析
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作者 杨丽珠 刘舒宜 何明影 《教育科学》 北大核心 2025年第1期51-59,共9页
在我国15省采用分层取样抽取3 544名幼儿,使用幼儿自我控制教师评定量表对其施测,运用潜在剖面分析和Logistic回归模型等方法,探讨幼儿自我控制类型及其发展特点。研究发现,我国幼儿自我控制可划分为三种类型:被动控制型、约束顺从型和... 在我国15省采用分层取样抽取3 544名幼儿,使用幼儿自我控制教师评定量表对其施测,运用潜在剖面分析和Logistic回归模型等方法,探讨幼儿自我控制类型及其发展特点。研究发现,我国幼儿自我控制可划分为三种类型:被动控制型、约束顺从型和自主控制型。小班幼儿以被动控制型和约束顺从型为主,小班下学期(3.5岁)被动控制型的占比开始下降。中班幼儿以约束顺从型为主,自主控制型的人数在增长,中班下学期(4.5岁)约束顺从型开始下降。大班幼儿约束顺从型和自主控制型的占比趋向平衡,大班下学期(5.5岁)自主控制型的占比快速上升。女童的被动控制型比例显著低于男童的被动控制型比例,而女童的自我控制水平比男童的自我控制水平高。建议教师和家长,针对幼儿自我控制三种类型的特征和3.5~4岁、4.5~5岁幼儿自我控制类型发展的敏感期进行培养。 展开更多
关键词 幼儿 自我控制类型 类型发展特点 潜在剖面分析 LOGISTIC回归模型
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间接空冷系统多级设备防冻特性及安全监测研究
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作者 王晓静 关欣 +5 位作者 陈良 张明玉 魏久程 郭欣荣 张冬月 王伟佳 《中国电机工程学报》 北大核心 2025年第6期2264-2273,I0019,共11页
间接空冷系统防冻模型是获取防冻特性的前提,而后者又是实施防冻监测的基础。为此,该文首先凝练空冷系统的热平衡方程、空气动力学平衡方程、防冻约束,以数理方程角度分析循环水流量和百叶窗开度作为防冻参数的选取依据及调控次序,并将... 间接空冷系统防冻模型是获取防冻特性的前提,而后者又是实施防冻监测的基础。为此,该文首先凝练空冷系统的热平衡方程、空气动力学平衡方程、防冻约束,以数理方程角度分析循环水流量和百叶窗开度作为防冻参数的选取依据及调控次序,并将机组背压、循环水流量、百叶窗开度与环境温度之间的函数关系确定为运行准则。其次,依托某工程实际间冷系统,采用数值模拟方法探究上下段空冷散热器-交错布置空冷扇区-冷却单元的临界防冻特性,重点分析典型工况的出口水温分布、波动范围、具体差异等。进而,量化多级空冷设备的防冻监测指标数据,为现场测点布置提供依据。结果表明,所提防冻数理模型、调控参数、案例分析思路具有普适性,可为间冷电站安全低碳运行提供参考。 展开更多
关键词 多级空冷设备 防冻数理模型 防冻调控参数 防冻特性 防冻监测
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Control of a flexible rotor active magnetic bearing test rig: a characteristic model based all-coefficient adaptive control approach 被引量:8
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作者 Long DI Zongli LIN 《Control Theory and Technology》 EI CSCD 2014年第1期1-12,共12页
Active magnetic bearings (AMBs) have found a wide range of applications in high-speed rotating machinery industry. The instability and nonlinearity of AMBs make controller designs difficult, and when AMBs are couple... Active magnetic bearings (AMBs) have found a wide range of applications in high-speed rotating machinery industry. The instability and nonlinearity of AMBs make controller designs difficult, and when AMBs are coupled with a flexible rotor, the resulting complex dynamics make the problems of stabilization and disturbance rejection, which are critical for a stable and smooth operation of the rotor AMB system, even more difficult. Proportional-integral-derivative (PID) control dominates the current AMB applications in the field. Even though PID controllers are easy to implement, there are critical performance limitations associated with them that prevent the more advanced applications of AMBs, which usually require stronger robustness and performance offered by modern control methods such as H-infinity control and if-synthesis. However, these advanced control designs rely heavily on the relatively accurate plant models and uncertainty characterizations, which are sometimes difficult to obtain. In this paper, we explore and report on the use of the characteristic model based all-coefficient adaptive control method to stabilize a flexible rotor AMB test rig. In spite of the simple structure of such a characteristic model based all-coefficient adaptive controller, both simulation and experimental results show its strong performance. 展开更多
关键词 Active magnetic bearings Adaptive control characteristic modeling Flexible rotor ROBUSTNESS
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Characteristic modeling and the control of flexible structure 被引量:19
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作者 吴宏鑫 刘一武 +1 位作者 刘忠汉 解永春 《Science in China(Series F)》 2001年第4期278-291,共14页
Appropriate modeling for a controlled plant has been a remarkable problem in the control field. A new modeling theory, i.e. characteristic modeling, is roundly demonstrated. It is deduced in detail that a general line... Appropriate modeling for a controlled plant has been a remarkable problem in the control field. A new modeling theory, i.e. characteristic modeling, is roundly demonstrated. It is deduced in detail that a general linear constant high-order system can be equivalently described with a two-order time-varying difference equation. The application of the characteristic modeling method to the control of flexible structure is also introduced. Especially, as an example, the Hubble Space Telescope is used to illustrate the application of the characteristic modeling and adaptive control method proposed in this paper. 展开更多
关键词 characteristic modeling time-varying difference equation flexible structure adaptive control.
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Intelligent control based on intelligent characteristic model and its application 被引量:11
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作者 吴宏鑫 王迎春 邢琰 《Science in China(Series F)》 2003年第3期225-240,共16页
This paper presents a new intelligent control method based on intelligent characteristic model for a kind of complicated plant with nonlinearities and uncertainties, whose controlled output variables cannot be measure... This paper presents a new intelligent control method based on intelligent characteristic model for a kind of complicated plant with nonlinearities and uncertainties, whose controlled output variables cannot be measured on line continuously. The basic idea of this method is to utilize intelligent techniques to form the characteristic model of the controlled plant according to the principle of combining the characteristics of the plant with the control requirements, and then to present a new design method of intelligent controller based on this characteristic model. First, the modeling principles and expression of the intelligent characteristic model are presented. Then based on description of the intelligent characteristic model, the design principles and methods of the intelligent controller composed of several open-loops and closed-loops sub controllers with qualitative and quantitative information are given. Finally, the application of this method in alumina concentration control in the real aluminum electrolytic process is introduced. It is proved in practice that the above methods not only are easy to implement in engineering design but also avoid the trial-and-error of general intelligent controllers. It has taken better effect in the following application: achieving long-term stable control of low alumina concentration and increasing the controlled ratio of anode effect greatly from 60% to 80%. 展开更多
关键词 intelligent characteristic model intelligent control adaptive fuzzy control aluminum electro-lytic process control.
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Characteristic model based control of the X-34 reusable launch vehicle in its climbing phase 被引量:12
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作者 MENG Bin WU HongXin +1 位作者 LIN ZongLi LI Guo 《Science in China(Series F)》 2009年第11期2216-2225,共10页
In this paper, a characteristic model based longitudinal control design for the trans-aerosphere vehicle X-34 in its transonic and hypersonic climbing phase is proposed. The design is based on the dynamic characterist... In this paper, a characteristic model based longitudinal control design for the trans-aerosphere vehicle X-34 in its transonic and hypersonic climbing phase is proposed. The design is based on the dynamic characteristics of the vehicle and the curves it is to track in this climbing phase. Through a detailed analysis of the aerodynamics and vehicle dynamics during this climbing phase, an explicit description of the tracking curve for the flight path angle is derived. On the basis of this tracking curve, the tracking curves for the two short-period variables, the angle of attack and the pitch rate, are designed. An all-coefficient adaptive controller is then designed, based on the characteristic modeling, to cause these two short-period variables to follow their respective tracking curves. The proposed design does not require multiple working points, making the design procedure simple. Numerical simulation is performed to validate the performance of the controller. The simulation results indicate that the resulting control law ensures that the vehicle climbs up successfully under the restrictions on the pitch angle and overloading. 展开更多
关键词 trans-aerosphere vehicle X-34 climbing phase characteristic modeling adaptive control ROBUSTNESS
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Coordination control strategy based on characteristic model for 3-bearing swivel duct nozzles 被引量:4
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作者 WANG Xiang Yang ZHU Ji Hong +1 位作者 YANG Jia Li LIU Kai 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第12期2347-2356,共10页
A coordination control strategy is developed for 3-bearing swivel duct (3BSD) nozzles. A 3BSD nozzle's deflection angle and direction are changed through rotations of three revolute pairs. There is a nonlinear rela... A coordination control strategy is developed for 3-bearing swivel duct (3BSD) nozzles. A 3BSD nozzle's deflection angle and direction are changed through rotations of three revolute pairs. There is a nonlinear relationship between the deflection an- gle/direction and the rotation angles. The rotation speed of a revolute pair is limited by the power of the actuator. The moment of inertia and the aerodynamic load for each revolute pair are different and time-varying. A high-precision control system of 3BSD nozzles is required for applications on vertical and/or short take-off and landing (V/STOL) aircrafts. Difficulties of co- ordination control of 3BSD nozzles are distinct travel ranges, speed constraints, time^xarying dynamic models, and disturb- ances. The proposed control strategy is a combination of the characteristic model and tlF e dynamic control allocation method. A dynamic control allocation module is used as the coordination supervisor, which is aware of the kinematic model, the con- straints, and the dynamic models of the revolute pairs. Second-order characteristic models are used to represent the dynamic behavior of the revolute pairs. The gradient projection algorithm is modified for parameter estimation. A modified all-coefficient adaptive controller is developed to reject the disturbances. Experimental results of a scaled 3BSD nozzle indi- cate that the coordination control strategy is effective. 展开更多
关键词 3-bearing swivel duct nozzle thrust vector coordination control characteristic model adaptive control dynamic con-trol allocation
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