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基于ESO-CPC的激光追踪测量系统电机仿真方法

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哈尔滨工程大学学报 2020年第2期41卷 235-242页

作者：孙衍强陈洪芳石照耀宋辉旭李长亮孙若水北京工业大学北京市精密测控技术与仪器工程技术研究中心

针对常规的PID方法控制电机已不能满足激光追踪测量系统中高精密测量要求的问题,本文结合永磁同步电机的数学模型和激光追踪测量系统的电流控制方法,建立了基于扩张状态观测器电流预测控制算法模型,并运用Matlab/Simulink软件进行仿真... 详细信息

针对常规的PID方法控制电机已不能满足激光追踪测量系统中高精密测量要求的问题,本文结合永磁同步电机的数学模型和激光追踪测量系统的电流控制方法,建立了基于扩张状态观测器电流预测控制算法模型,并运用Matlab/Simulink软件进行仿真分析。仿真结果表明:激光追踪测量系统电机控制模型的有效性,避免了由模型误差和不确定性干扰的影响和电机的内外扰动,能够有效地减小激光追踪控制系统电流环扰动和转矩波动,并且激光追踪测量系统表现出较好的动态响应特性和速度控制特性;对提高系统稳态跟踪精度、增强系统鲁棒性有重要的现实意义。

关键词：激光追踪测量电流预测控制扩张状态观测器电机控制电机建模控制算法永磁同步电机 Simulink仿真

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点激光扫描齿轮测量中齿圈径向跳动计算方法

工具技术 2022年第12期56卷 135-140页

作者：尹欣孙衍强石照耀北京工业大学材料与制造学部北京市100124 北京市精密测控技术与仪器工程技术研究中心

径向跳动是表征齿轮精度的一个常用指标,传统获取方法包括采用径跳仪直接测量和基于齿轮测量中心的间接计算。采用点激光全圆周扫描齿轮,用两种方法计算出齿圈径向跳动:一是虚拟测球滚动接触方法,通过迭代优化测球运动路径,实现测球在... 详细信息

径向跳动是表征齿轮精度的一个常用指标,传统获取方法包括采用径跳仪直接测量和基于齿轮测量中心的间接计算。采用点激光全圆周扫描齿轮,用两种方法计算出齿圈径向跳动:一是虚拟测球滚动接触方法,通过迭代优化测球运动路径,实现测球在齿廓固定位置的相切定位,计算得到齿圈径向跳动偏差;二是齿面间接计算方法,通过齿廓渐开线定向偏移,计算确定偏移渐开线的交点位置并得到齿圈径向跳动偏差。在齿轮测量中心上进行测量实验,结果表明,采用以上两种方法得到的齿圈径向跳动偏差结果与齿轮测量中心的测量结果分别相差0.3μm和0.7μm;本文研究的齿圈径向跳动计算方法具有较好的测量精度,与传统测量方法相比具有较好的一致性。

关键词：齿轮测量点激光径向跳动齿轮

Divergent responses of runoff to climate change in the upper basins of the Third Pole dominated by westerlies and monsoon

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Science China Earth Sciences 2024年第8期67卷 2592-2614页

作者： Qikai sun Fengge SU He sun State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100101China

The diverse climates,distribution of snow and glaciers,and geographic locations directly affect the runoff response to climate change in the upper basins of the Third *** present,a comprehensive analysis of runoff variations and their distinct responses to climate change in the westerlies-and monsoon-dominated upper basins is still *** study comprehensively analyzed annual runoff variations in westerlies-dominated basins(the upper basins of the Aksu(UAKS),Syr Darya(USRD),Yarkant(UYK),Hotan(UHT),Amu Darya(UAMD),and Indus(UI))and monsoon-dominated basins(the upper basins of the Yangtze(UYA),Yellow(UYE),Lancang(ULC),Nujiang(UNJ),and Yarlung Zangbo(UYZ))of the Third Pole from 1961 *** multi-source meteorological data and large-scale circulation factors,this study investigated the divergent responses of runoff in the upper basins to climate change,and explored the large-scale circulation mechanisms underlying runoff variations in these upper *** results showed that:(1)The annual runoff in the majority of upper basins(except for the UYE and UYZ)exhibited an increasing trend,and the annual runoff in the UAKS,UYK,and UI showed a significant increasing trend from1961 to *** annual runoff in the upper basins of the Third Pole changed abruptly from decreasing to increasing between the 1980s and 2000s,with the exception of the UYE.(2)The runoff in the monsoon-dominated upper basins has been controlled primarily by changes in precipitation over the past 55 *** contrast,the runoff in the westerlies-dominated upper basins exhibited three distinct long-term responses to climate change:temperature-dominated(UYK and UHT),precipitation-dominated(USRD and UAMD),and the combined influence of precipitation and temperature(UAKS and UI).Since the 1960s,the sensitivity of runoff to warm season temperature changes in the most westerlies-dominated upper basins has decreased,while the response of runoff to precipitation changes has intensified.(3)The stud

关键词： Upper basins of the Third Pole Climate change Westerlies and monsoon Runoff variations Large-scale circulation factors

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New perspectives on deep carbon cycling

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Science China Earth Sciences 2024年第8期67卷 2411-2422页

作者： Weidong sun Center of Deep Sea Research Key Laboratory of Ocean Observation and ForecastingInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Laoshan Laboratory Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China

The proto-atmosphere serves as a crucial starting point for the carbon *** based on atmospheric data from Mars and Venus suggest that Earth's proto-atmosphere contained>110 bar of CO_(2)and>2.6 bar of *** protoatmosphere had over 1000 bar of water vapor during the magma ocean stage,assuming the proto-ocean had a volume of two oceans of *** this stage both water and carbon dioxide were in a supercritical state at the magma-atmosphere *** serpentinization reactions occurred due to rock-water interaction,producing abundant ***,nitrogen is reduced to ammonia,and carbon dioxide to methane,forming carbonate *** proto-atmosphere dominated by methane,ammonia,and hydrogen formed a significant amount of amino acids through *** process is essential not only to the origin of life,but also to the early carbon-nitrogen cycle on *** the Hadean eon,a large amount of CO_(2)was sequestered as carbonate and organic ***,it mainly entered the deep mantle through mantle overturn or *** the mantle transition zone,carbonate undergoes“Redox freezing”,where carbonate is reduced to diamond through oxidation of ferrous iron in the *** the lower mantle,Fe^(2+)undergoes disproportionation reactions,forming Fe^(3+)and metallic *** these,Fe^(3+)mainly resides in bridgmanite,thereby increasing the oxygen fugacity of the lower mantle,while metallic iron falls to the Earth's *** distribution of carbon in the mantle is crucial for deep carbon *** density curves of diamond and mantle peridotite melt intersect at the bottom of the mantle transition zone(about 660 km).This density crossover leads to the accumulation of diamond during the magma ocean *** materials such as subducting slabs enter the lower mantle,compensatory upwelling of lower mantle material *** enters the upper mantle,decomposes,releasing Fe^(3+)ions and oxidizes diamond

关键词： Carbon cycling Proto-atmosphere Amino acids Subduction initiation Passive margin subduction Atmospheric carbon dioxide

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高精度激光追踪测量方法及实验研究

中国激光 2018年第1期45卷 160-167页

作者：陈洪芳孙衍强王亚韦石照耀宋辉旭北京工业大学北京市精密测控技术与仪器工程技术研究中心北京100124

为满足现代工业各领域对高精度、大测量范围、实时性测量的要求,提出一种高精度激光追踪测量方法,来实现对随动目标的精密追踪测量。基于四象限探测器的激光追踪测量系统可实时地测量入射激光光斑相对于四象限探测器中心的偏移量,利用... 详细信息

为满足现代工业各领域对高精度、大测量范围、实时性测量的要求,提出一种高精度激光追踪测量方法,来实现对随动目标的精密追踪测量。基于四象限探测器的激光追踪测量系统可实时地测量入射激光光斑相对于四象限探测器中心的偏移量,利用响应速度快的伺服电机、可编程多轴运动控制器(PMAC)的运动控制卡构建闭环控制系统,实现高精度快速激光追踪测量。实验结果表明,所提出的高精度激光追踪测量方法实时性好、测量精度高;当在激光光斑距离四象限探测器中心±1000μm范围内追踪测量时,光斑偏移量误差为31.2μm,激光光斑返回四象限探测器中心的平均时间为0.259ms。

关键词：测量激光追踪测量光斑偏移量闭环控制高精度测量

基于双曲正切函数的改进型永磁同步电机无感矢量控制系统

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哈尔滨工程大学学报 2021年第5期42卷 710-718页

作者：张攀石照耀林家春于渤孙衍强丁宏钰北京工业大学精密测控技术与仪器工程技术研究中心北京100124

针对滑模观测器在永磁同步电机无位置传感器控制系统中存在的高频抖振、观测精度差等问题,本文提出了一种改进型滑模观测器无位置传感器控制方法。采用双曲正切函数代替传统开关函数,推导了基于双曲正切函数的滑模观测器转子位置估算算... 详细信息

针对滑模观测器在永磁同步电机无位置传感器控制系统中存在的高频抖振、观测精度差等问题,本文提出了一种改进型滑模观测器无位置传感器控制方法。采用双曲正切函数代替传统开关函数,推导了基于双曲正切函数的滑模观测器转子位置估算算法,并使用李雅普诺夫稳定性分析方法对系统进行了稳定性分析,得到了进入滑模面的充分条件。使用卡尔曼滤波方法对得到的反电动势进行滤波处理,并通过锁相环估算转子的位置的方法提高了速度、位置观测精度。最后,通过Simulink平台搭建了改进型滑模观测器仿真模型并与开关函数、饱和函数做了对比分析。结果表明:相比传统滑模观测器,所提出的改进型滑模观测器启动过程更加平稳,并明显改善了稳态运行过程中的高频抖振现象。改进后的观测器具有更高的观测精度,更强的抗干扰能力及稳定性。

关键词：永磁同步电机滑模观测器双曲正切函数无感控制卡尔曼滤波矢量控制抖振

Fossil Equidae in the Linxia Basin with Biostratigraphic and Paleozoogeographic Significance

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 1-9页

作者： sun Boyang Key Laboratory of Vertebrate Evolution and Human Origins of the Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China

The Linxia Basin is characterized by an abundance of Cenozoic sediments,that contain exceptionally rich fossil *** are abundant in the Linxia Basin,the fossil record of equids in this region including 16 species that represent 10 *** comparison to other classic late Cenozoic areas in China,the Linxia Basin stands out,because the fauna and chronological data accompanying Linxia equids render them remarkably useful for *** anchitheriines in the region,such as Anchitherium and Sinohippus,represent early equids that appeared in the late stages of the middle and late Miocene,*** the equines,most species of Chinese hipparions have been identified in the Linxia Basin and some species of the genera Hipparion and Hippotherium have FAD records for ***,Equus eisenmannae is one of the earliest known species of Equus in the Old World and is well-represented at the Longdan *** species with precise geohistorical distributions can serve as standards for high-resolution chronological units within this *** at the eastern margin of the Tibetan Plateau and subject to considerable uplift,the Linxia Basin has served as a biogeographic transition area for equids throughout the late Cenozoic.

关键词： Equidae Cenozoic biostratigraphy paleozoogeography Linxia Basin

Achieving simultaneously high conversion and high selectivity for light olefins directly producing from syngas

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Science China Chemistry 2024年第3期67卷 753-754页

作者： Yuhan sun Shanxi Research Institute Huairou Research LaboratoryTaiyuan 030032China Institute of Carbon Neutrality ShanghaiTech UniversityShanghai 201210China

The activity and selectivity are two primary indexes of a successful catalyst for chemical reactions. However,achieving a high activity and a high selectivity simultaneously is a long-standing challenge in catalysis, the socalled activity-selectivity trade-off. In the article recently published in Science, a research team led by Prof.

关键词： selectivity simultaneous catalysis

ONE-PARAMETER FINITE DIFFERENCE METHODS AND THEIR ACCELERATED SCHEMES FOR SPACE-FRACTIONAL SINE-GORDON EQUATIONS WITH DISTRIBUTED DELAY

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Journal of Computational Mathematics 2024年第3期42卷 705-734页

作者： Tao sun Chengjian Zhang Haiwei sun School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory of Engineering Modeling and Scientific Computing Huazhong University of Science and TechnologyWuhan 430074China Department of Mathematics University of MacaoMacaoChina

This paper deals with numerical methods for solving one-dimensional(1D)and twodimensional(2D)initial-boundary value problems(IBVPs)of space-fractional sine-Gordon equations(SGEs)with distributed *** 1D problems,we construct a kind of oneparameter finite difference(OPFD)*** is shown that,under a suitable condition,the proposed method is convergent with second order accuracy both in time and *** implementation,the preconditioned conjugate gradient(PCG)method with the Strang circulant preconditioner is carried out to improve the computational efficiency of the OPFD *** 2D problems,we develop another kind of OPFD *** such a method,two classes of accelerated schemes are suggested,one is alternative direction implicit(ADI)scheme and the other is ADI-PCG *** particular,we prove that ADI scheme can arrive at second-order accuracy in time and *** some numerical experiments,the computational effectiveness and accuracy of the methods are further ***,for the suggested methods,a numerical comparison in computational efficiency is presented.

关键词： Fractional sine-Gordon equation with distributed delay One-parameter finite difference methods Convergence analysis ADI scheme PCG method