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Guaranteeing the Fault Transient Performance of Aerospace Multiphase Permanent Magnet Motor System: an Adaptive Robust Speed Control Approach

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CES Transactions on Electrical Machines and Systems 2020年第2期4卷 114-122页

作者： jinquan Xu Boyi Zhang Hao Fang Hong guo School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China

To enhance the fault transient performance of aerospace multiphase permanent magnet synchronous motor(PMSM)system,an adaptive robust speed control is proposed regardless of the phase open-circuit(OC)and short-circuit(SC)fault in this paper,which can be applied for both the redundant motor system and fault tolerant motor *** aerospace multiphase PMSM system,besides external load disturbance and system parameter perturbation,there inevitably exists the electromagnetic torque ripple in fault transient process,which can degrade the system performance and even cause the system *** cope with this issue,the electromagnet torque ripple of the multiphase PMSM system in fault transient process is first ***,by considering the electromagnet torque fluctuation caused by fault transient as a system uncertainty,a novel adaptive robust speed control scheme is proposed,while the adaptive law is constructed to emulate the total system uncertainty bound,which include the load disturbance,the parameter variation,and the electromagnetic torque fluctuation due to fault *** resulting control can ensure the speed control performance even in fault transient process regardless of the uncertainty,in which no prior estimation of the uncertainty bound is *** addition,the proposed adaptive robust speed control is demonstrated by a six-phase PMSM experimental *** novelty of this research is to explore a novel adaptive robust speed control to strengthen the fault tolerance performance of multiphase PMSM system even in fault transient process,which requires no prior estimation of the uncertainty bound.

关键词： Multiphase permanent magnet motor fault transient fault tolerance adaptive robust control.

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铜镍合金选择性两段加压浸出试验研究

中国有色冶金 2023年第2期52卷 157-163页

作者：贺来荣苏俊敏赵秀丽郭金权陈彩霞宗红星张媛庆马军虎欧晓健席海龙李全镍钴资源综合利用国家重点实验室甘肃金昌737100 金川集团股份有限公司甘肃金昌737100

现有火法工艺处理铜镍合金时,存在物料反复冶炼、周转量大、贵金属分散、回收率低的问题,湿法工艺存在全浸液铜、镍分离难度大的问题。本文在分析铜镍合金成分的基础上,以镍冶炼厂产出的铜镍合金为原料开展试验研究,一段工序采用CuSO_(4... 详细信息

现有火法工艺处理铜镍合金时,存在物料反复冶炼、周转量大、贵金属分散、回收率低的问题,湿法工艺存在全浸液铜、镍分离难度大的问题。本文在分析铜镍合金成分的基础上,以镍冶炼厂产出的铜镍合金为原料开展试验研究,一段工序采用CuSO_(4)作为浸出剂,将镍单质和硫化镍转变为镍离子进入溶液,而铜离子形成沉淀进入渣相,实现镍的选择性浸出;二段工序在浸出渣中加入硫酸并通入氧气,将单质铜和硫化铜全部浸出,贵金属富集于渣中;三段工序对硫酸铜溶液进行浓缩结晶。结果表明,控制合适的两段加压浸出条件,产出总渣率为4.61%,铜的总浸出率为99.19%,镍的总浸出率为99.43%,贵金属富集倍数为21.69。浸铜液经浓缩结晶,产出硫酸铜结晶纯度为98.35%,符合硫酸铜结晶产品一级品标准要求。该工艺试剂用量少、无废水排放,是一种绿色环保工艺,具有推广价值。

关键词：铜镍合金铜镍分离选择性浸出绿色冶金贵金属回收

Novel carbon nanohybrids as highly efficient magnetic resonance imaging contrast agents

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Nano Research 2015年第4期8卷 1259-1268页

作者： Rongli Cui Juan Li Huan Huang Mingyi Zhang Xihong guo Yanan Chang Min Li jinquan Dong Baoyun Sun Gengmei Xing CAS Key Laboratory for Biomedical Effects of Nanomaterial & Nanosafety Institute of High Energy Physics Chinese Academy otScience (CAS) Beijing 700049 China

Novel carbon nanohybrids based on unmodified metallofullerenes have been successfully fabricated for use as a new magnetic resonance imaging （MRI） contrast agent. The nanohybrids showed higher R1 relaxivity and better brightening effect than Gd@C82（OH）x, in Tl-weighted MR images in vivo. This is a result of the proton relaxivity from the original gadofullerenes, which retained a perfect carbon cage structure and so might completely avoid the release of Gd^3＋ ions. A ＂secondary spin-electron transfer＂ relaxation mechanism was proposed to explain how the encaged Gd^3＋ ions of carbon nanohybrids interact with the surrounding water molecules. This approach opens new opportunities for developing highly efficient and low toxicity MRI contrast agents.

关键词： graphene oxide metallofullerene magnetic resonanceimaging (MRI) nanohybrids

Feasibility of differentiating defect signals of ultrasonic testing for laser weld based on independent component analysis theory

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Rare Metals 2007年第S1期26卷 56-60页

作者： guo Liwei,GANG Tie,and LI jinquan State Key Laboratory of Advanced Welding Production Technology,Harbin Institute of Technology,Harbin 150001,China Harbin Inst Technol State Key Lab Adv Welding Prod Technol Harbin 150001 Peoples R China

Separating noise from observed signals was *** the small defect in the T-shape laser welding joint was inspected by ultrasonic testing system adopting independent component analysis(ICA) theory to process the *** principle of automatic ultrasonic testing signals processing and negentropy law of ICA were *** experimental data were processed using relative analysis tools and results showed that the ICA could separate defects signals from noise effectively in laboratory.

关键词： independent component analysis automatic ultrasonic testing signal processing

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六相永磁容错轮毂电机多物理场综合设计方法

北京航空航天大学学报 2019年第3期45卷 520-528页

作者：郭嗣郭宏徐金全北京航空航天大学自动化科学与电气工程学院北京100083

针对电动装甲车用轮毂电机工况复杂多变,发热严重的问题,通过对电机所涉及各物理场之间关系的分析,提出了一种永磁容错轮毂电机多物理场设计方法。利用该方法对一台电动装甲车用额定功率50kW,最高转速6000r/min六相永磁容错轮毂电机进... 详细信息

针对电动装甲车用轮毂电机工况复杂多变,发热严重的问题,通过对电机所涉及各物理场之间关系的分析,提出了一种永磁容错轮毂电机多物理场设计方法。利用该方法对一台电动装甲车用额定功率50kW,最高转速6000r/min六相永磁容错轮毂电机进行了综合设计。在电机结构初步设计基础上,通过电磁-应力耦合分析,在兼顾电磁性能和转子强度的情况下对转子隔磁磁桥进行优化设计;通过电磁-温度耦合分析计算了电机内各区域温度分布,并对永磁体在极限温度下的退磁进行了校核;通过应力-温度耦合设计完成了转子与护套的最大应力计算,校核了护套厚度及过盈量。仿真结果表明,基于多物理场综合设计方法得到的电机能同时满足电磁性能、温度限制以及机械强度的要求,电机可靠性得到了提高。

关键词：永磁容错轮毂电机多物理场综合设计电磁场应力场温度场

Fabrication of large area hexagonal boron nitride thin films for bendable capacitors

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Nano Research 2013年第8期6卷 602-610页

作者： Ning guo jinquan Wei Yi Jia Huanhuan Sun Yuhang Wang Kehan Zhao Xiaolan Shi Liuwan Zhang Xinming Li Anyuan Cao Hongwei Zhu Kunlin Wang Dehai Wu Key Lab for Advanced Materials Processing Technology of Education Ministry School of Materials Science and Engineering Tsinghua University Beijing 100084 China Department of Physics Tsinghua University Beijing 100084 China Department of Materials Science and Engineering College of Engineering Peking University Beijing 100871 China

Highly reliable and bendable dielectrics are desired in flexible or bendable electronic devices for future applications. Hexagonal boron nitride （h-BN） can be used as bendable dielectric due to its wide band gap. Here, we fabricate high quality h-BN films with controllable thickness by a low pressure chemical vapor deposition method. We demonstrate a parallel-plate capacitor using h-BN film as the dielectric. The h-BN capacitors are reliable with a high breakdown field strength of -9.0 MV/cm. Tunneling current across the h-BN film is inversely exponential to the thickness of dielectric, which makes the capacitance drop significantly. The h-BN capacitor shows a best specific capacitance of 6.8 F/cm^2, which is one order of magnitude higher than the calculated value.

关键词： hexagonal boron nitride capacitor breakdown strength tunneling effect

Highly delocalized endohedral metal in Gd@C2v（9）-C82 metallofullerenes co-crystallized with α-Se

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Nano Research 2018年第4期11卷 2277-2284页

作者： Cheng Li Xuejiao J. Gao Huanli Yao Huan Huang Rongli Cui Xihong guo Lele Zhang Bing Liu Binggang Xu Weiqun Shi jinquan Dong Lai Feng Xingfa Gao Baoyun Sun CAS Key Lab for Biomedical Effects of Nanomaterials & Nanosafety Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China University of Chinese Academy of Sciences Beijing 100049 China College of Physics Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology Soochow University Suzhou 215006 China College of Chemistry and Chemical Engineering Jiangxi Normal University Nanchang 330022 China

A new Gd@C2v（9）-C82·2.5（S8）·0.5（CS2） co-crystal was prepared for the first time and characterized by single-crystal X-ray diffraction （XRD）. The analysis dearly showed that, even though the C2v（9）-C82 cage is fully ordered, the endohedral Gd atoms are highly disordered. This result indicates the presence of highly delocalized endohedral Gd atoms, which has never been reported before. Density functional theory （DFT） calculations were used to rationalize the XRD results. The calcula- tions reveal the presence of two local energy minima, a and b, with the latter existing as four conformers b1-b4. Whereas the energy difference between the two minima is calculated only - 10 kcal/mol, their interconversion is almost impossible due to a high energy barrier, of up to 35.98 kcal/mol. This suggests the existence of multiple low-energy positions for the endohedral Gd atom. In addition, a remarkable electron transfer from the C2d9）-C82 cage to the S8 moieties was demonstrated, which might result in a modified endohedral environment and further contribute to the occurrence of delocalized endohedral Gd atoms.

关键词： metallofullerenes sulfur structure elucidation delocalization density functional theory(DFT) calculations

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基于输入成形的太阳能帆板自适应滑模控制

北京航空航天大学学报 2018年第4期44卷 737-745页

作者：周通郭宏徐金全北京航空航天大学自动化科学与电气工程学院北京100083

为提高太阳能帆板驱动系统(SADS)的角位置控制性能和抑制太阳能帆板的柔性振动,提出了一种自适应滑模控制(ASMC)与输入成形技术相结合的控制策略。该控制策略通过自适应滑模控制保证了系统在不确定性影响下的一致有界性和渐进一致有界性... 详细信息

为提高太阳能帆板驱动系统(SADS)的角位置控制性能和抑制太阳能帆板的柔性振动,提出了一种自适应滑模控制(ASMC)与输入成形技术相结合的控制策略。该控制策略通过自适应滑模控制保证了系统在不确定性影响下的一致有界性和渐进一致有界性,从而提高了太阳能帆板驱动系统的角位置控制性能。同时,通过基于参考模型的输入成形器(IS)规划了指令轨迹,进而抑制了太阳能帆板的柔性振动。仿真结果表明了控制策略的有效性。

关键词：输入成形自适应滑模控制(ASMC) 太阳能帆板驱动系统柔性振动

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功率级无刷直流电动机四象限运行模拟器设计

北京航空航天大学学报 2021年第10期47卷 2043-2057页

作者：张磊郭宏徐金全北京航空航天大学自动化科学与电气工程学院北京100083

针对无刷直流电动机(BLDCM)驱动控制器在研发过程中全工况测试困难、测试成本高和研发周期长的问题,提出了一种采用分区间采样和解算方法的、具有四象限运行能力的功率级(PHIL)无刷直流电动机模拟器,替代实物电动机和机械负载装置完成... 详细信息

针对无刷直流电动机(BLDCM)驱动控制器在研发过程中全工况测试困难、测试成本高和研发周期长的问题,提出了一种采用分区间采样和解算方法的、具有四象限运行能力的功率级(PHIL)无刷直流电动机模拟器,替代实物电动机和机械负载装置完成对两两导通控制方式下无刷直流电动机驱动控制器的各项性能测试与可靠性试验。该模拟器由实时仿真器、电动机模拟变换器和多级式双向变换器3部分组成,实时仿真器负责采集被测电动机驱动控制器输出的PWM电压,实时解算电动机模型得到三相电流指令,控制电动机模拟变换器生成三相电流,多级式双向变换器负责维持模拟器输入、输出间的能量平衡关系,从而实现对四象限运行时无刷直流电动机的功率级模拟。实验结果表明:所提出的功率级无刷直流电动机模拟器模拟精度高、实时性好、测试灵活,能够有效替代实物电动机和机械负载装置,满足电动机驱动控制器的测试需求。

关键词：功率级(PHIL)电动机模拟器四象限运行无刷直流电动机(BLDCM) 实时仿真器电动机模拟变换器