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基于长周期暂态信号分析的电机驱动变换器直流母线电容在线状态监测

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电力系统保护与控制 2024年第16期52卷 120-131页

作者：王要强李锐陈天锦聂福全赖锦木梁军郑州大学电气与信息工程学院河南郑州450001 河南省电力电子与电力系统工程技术研究中心河南郑州450001 许继电源有限公司河南许昌461000 河南省智能充电技术重点实验室河南许昌461000 河南科技学院机电学院河南新乡453003 卡迪夫大学工程学院英国卡迪夫CF243AA

直流母线电容作为电机驱动变换器中最薄弱的元件之一,其老化会导致系统故障的概率增大,因此对电容老化进行在线监测至关重要。针对现有监测方法存在经济性差、采样频率高、影响系统正常运行等问题,提出一种基于长周期暂态信号分析的电... 详细信息

直流母线电容作为电机驱动变换器中最薄弱的元件之一,其老化会导致系统故障的概率增大,因此对电容老化进行在线监测至关重要。针对现有监测方法存在经济性差、采样频率高、影响系统正常运行等问题,提出一种基于长周期暂态信号分析的电容在线监测方法,用于估计电机驱动变换器直流母线等值串联电容(equivalent series capacitance,ESC)。首先,根据系统负载切换过程建立共节点感-容等值暂态模型,分析长周期暂态信号特点。其次,推导基于长周期暂态信号的在线监测模型,确定监测程序启动判定条件。然后,提出一种基于多项式重构的电容电流基线校准方法,消除传感器零漂影响,提高监测精度。最后,仿真和实验表明所提出方法的监测精度满足电容监测的要求。

关键词：电机驱动变换器电容器老化等值串联电容在线监测长周期暂态信号

Special issue： Nanotechnology in energy

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Frontiers in Energy 2018年第1期12卷 1-4页

作者： changying ZHAO Zhuomin ZHANG Xing ZHANG Institute of engineering Thermophysics Shanghai Jiao Tong UniversityShanghai 200240 China George W. Woodruff school of mechanical engineering GeorgiaInstitute of Technology Atlanta GA 30332 USA Key Laboratory for Thermal science and Power engineering of Ministryof Education Department of Engineering Mechanics TsinghuaUniversity Beijing 100084 China

Nanostructured materials exhibit exotic properties for thermal transport and storage as well as light absorption. The aim of this special issue is to provide a small collection from a large field of nanotechnology related to energy applications. Nano/microscale heat and mass transfer plays an important role in emerging energy systems and thermal management.

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A Telepresence-Guaranteed Control Scheme for Teleoperation Applications of Transferring Weight-Unknown Objects

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IEEE/CAA Journal of Automatica Sinica 2022年第6期9卷 1015-1025页

作者： Jinfei Hu Zheng Chen Xin Ma Han lai Bin Yao State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China IEEE Ocean College Zhejiang UniversityZhoushan 316021 the State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027 Ocean Research Center of Zhoushan Zhejiang UniversityZhoushan 316021China school of engineering technology Purdue UniversityWest LafayetteIN 47907 USA Department of mechanical and Automation engineering The Chinese University of Hong KongHong Kong 999077China school of mechanical engineering Purdue UniversityWest LafayetteIN 47907 USA

Currently,most teleoperation work is focusing on scenarios where slave robots interact with unknown ***,in some fields such as medical robots or rescue robots,the other typical teleoperation application is precise object ***,the object’s weight is unknown yet essential for both accurate control of the slave robot and intuitive perception of the human ***,due to high cost and limited installation space,it is unreliable to employ a force sensor to directly measure the ***,in this paper,a control scheme free of force sensor is proposed for teleoperation robots to transfer a weight-unknown object *** this scheme,the workspace mapping between master and slave robot is firstly established,based on which,the operator can generate command trajectory on-line by operating the master ***,a slave controller is designed to follow the master command closely and estimate the object’s weight rapidly,accurately and robust to unmodeled ***,for the sake of telepresence,a master controller is designed to generate force feedback to reproduce the estimated weight of the *** the end,comparative experiments show that the proposed scheme can achieve better control accuracy and telepresence,with accurate force feedback generated in only 500 ms.

关键词： Adaptive robust control teleoperation telepresence transparency weight estimation

旋转超声加工对TiBw网状钛基复合材料表面残余应力的影响

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陕西师范大学学报（自然科学版） 2024年第2期52卷 8-13页

作者：董国军郭志清代勇赖睿达刘荣松哈尔滨工业大学机电工程学院黑龙江哈尔滨150001

为研究不同切削条件下旋转超声加工对材料表面残余应力的影响,选取硼化钛晶须(TiB whiskers,TiBw)网状钛基复合材料为实验对象,使用镍基电铸金刚石砂轮进行旋转超声加工,并分析了加工后材料的表面残余应力。结果表明:由于钛基复合材料... 详细信息

为研究不同切削条件下旋转超声加工对材料表面残余应力的影响,选取硼化钛晶须(TiB whiskers,TiBw)网状钛基复合材料为实验对象,使用镍基电铸金刚石砂轮进行旋转超声加工,并分析了加工后材料的表面残余应力。结果表明:由于钛基复合材料具有网状结构和优异的高温性能,使切削热和微观相变产生的残余应力较小,磨粒机械作用产生的残余应力更大。随着超声振动的引入,磨粒高频冲击工件表面,使旋转超声加工工件表面残余应力均大于普通磨削。在主轴转速n=9000 r/min,进给速度v f=8 mm/min,加工深度a p=25μm的加工参数下,旋转超声加工工件表面存在-540 MPa的残余压应力,随着主轴转速增大,残余应力显著减小,并且残余应力的影响层深度逐渐减小。超声振动的引入增大工件表面残余压应力,提高材料抗疲劳性能。

关键词：旋转超声加工 TiBw网状增强钛基复合材料残余应力

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Steering CO_(2)electrolysis selectivity by modulating the local reaction environment:An online DEMS approach for Cu electrodes

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escience 2023年第4期3卷 89-98页

作者： Ke Ye Guiru Zhang Baoxin Ni Liang Guo Chengwei Deng Xiaodong Zhuang changying Zhao Wen-Bin Cai Kun Jiang Interdisciplinary Research Center School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China china-UK Low Carbon College Shanghai Jiao Tong UniversityShanghai 201306China State Key Laboratory of Space Power-Sources technology Shanghai Institute of Space Power SourcesShanghai 200245China school of Chemistry and Chemical engineering Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Collaborative Innovation Center of Chemistry for Energy MaterialsDepartment of ChemistryFudan UniversityShanghai 200438China

Electrochemical CO_(2)reduction is a typical surface-mediated reaction,with its reaction kinetics and product distributions largely dependent on the dynamic evolution of reactive species at the cathode–catholyte interface and on the resultant mass transport within the hydrodynamic boundary layer in the vicinity of the *** resolve the complex local reaction environment of branching CO_(2)reduction pathways,we here present a dif-ferential electrochemical mass spectroscopic(DEMS)approach for Cu electrodes to investigate CO_(2)mass trans-port,the local concentration gradients of buffering anions,and the Cu surface topology effects on CO_(2)electrolysis selectivity at a temporal resolution of~400 *** a proof of concept,these tuning knobs were validated on an anion exchange membrane electrolyzer,which delivered a Faradaic efficiency of up to 40.4%and a partial current density of 121 mA cm^(-2)for CO_(2)-to-C_(2)H_(4)*** methodology,which bridges the study of fundamental surface electrochemistry and the upgrading of practical electrolyzer performance,could be of general interest in helping to achieve a sustainable circular carbon economy.

关键词： Spectroelectrochemistry CO_(2)reduction reaction Copper electrode Differential electrochemical mass spectroscopy Local reaction environment

Robust adaptive precision motion control of tank horizontal stabilizer based on unknown actuator backlash compensation

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Defence technology（防务技术） 2023年第2期20卷 72-83页

作者： Shu-Sen Yuan Wen-Xiang Deng Jian-Yong Yao Guo-lai Yang school of mechanical engineering Nanjing University of Science and TechnologyNanjingChina

Backlash nonlinearity inevitably exists in the actuator of tank horizontal stabilizer and has adverse effect on the system control performance,however,how to effectively eliminate its effect remains a pending *** solve this problem,a robust adaptive precision motion controller is presented in this paper to address uncertainties and unknown actuator backlash of tank horizontal *** controller handles the modeling uncertainties including parameter uncertainties and unmodeled disturbances by integrating adaptive feedforward compensation and continuous nonlinear robust *** on the backstepping method,a smooth backlash inverse model is constructed by combining the adaptive ***,the unknown backlash parameters of the system can be approximated through the parameter adaptation,and the impact of the actuator backlash nonlinearity is effectively compensated via the inverse operation,which can availably improve the tracking ***,the adaptive law can update the disturbance ranges of tank horizontal stabilizer online in real time,which enhances the feasibility in practical engineering ***,the stability analysis based on Lyapunov function shows that with the existence of unmodeled disturbances and unknown actuator backlash,the designed controller guarantees excellent asymptotic output tracking *** comparative results verify the effectiveness of the proposed control strategy.

关键词： Tank Horizontal stabilizer Adaptive control Robust control Backlash inverse

Self-healing of microcapsule-based materials for highway construction:A review

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Journal of Traffic and Transportation engineering(English Edition) 2023年第3期10卷 368-384页

作者： Enlin Ma Xi Chen Jinxing lai Xiangze Kong Chunxia Guo school of Highway Chang'an UniversityXi'an 710064China Department of Civil engineering Aalto UniversityAalto 00076Finland Southwest Municipal engineering Design&Research Institute of china Chengdu 610299China Department of Chemistry and Materials science Aalto UniversityAalto 00076Finland school of science Xi'an University of Architecture and TechnologyXi'an 710055China

Maintaining the health and reliability of civil facilities is of strategic *** highway engineering,pavement cracking impairs the road service and travel comfort level,while structure cracking can cause catastrophic ***-based self-healing materials offer solutions to auto-recovery micro-cracks and maintain structural *** solution has become available by laboratory synthesis and proved effective in addressing the cracking problem during long-term mechanical,thermal,and hydraulic ***,full-scale applications of this technique are not prevalent,showing its potential limitations in highway *** healing in highways is a big topic,therefore,this review has two insertion points.(1)We focus on the cracking issues on two specific materials:asphalt and concrete,which account for the vast majority of all the materials used in pavement and structures in highways.(2)Instead of the laboratory studies,we pay more attention to the practical applications,the meaning of healing performance,and the adverse effects of microcapsules to the main structural components(i.e.,tunnel lining,bridge piers and beams)and pavement in *** practical significance of self-healing materials in highway projects was discussed from the three aspects:strength,durability,and stress *** difficulty in applying this new technique is also discussed from economic *** future-proofing,a material evaluation system that fits the load condition is *** self-healing technique brings composites a chance to interact with the environment,showing high potential for contributing to the development of various types of long-lasting infrastructures.

关键词： Road engineering Self-healing material Structure cracking Micro-encapsulation Facility lifetime

Recent advancement of flow-induced piezoelectric vibration energy harvesting techniques:principles,structures,and nonlinear designs

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Applied Mathematics and Mechanics(English Edition) 2022年第7期43卷 959-978页

作者： Dongxing CAO Junru WANG Xiangying GUO S.K.lai Yongjun SHEN Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China Beijing Key Laboratory of Nonlinear Vibrations and Strength of mechanical Structures Beijing 100124China school of Automation Beijing Information Science and Technology UniversityBeiing 100192China Department of Civil and Environmental engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina Hong Kong Branch of National Rail Transit Electrification and Automation engineering technology Research Center The Hong Kong Polytechnic UniversityKowloonHong KongChina State Key Laboratory of mechanical Behavior and System Safety of Traffic engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China

Energy harvesting induced from flowing fluids(e.g.,air and water flows)is a well-known process,which can be regarded as a sustainable and renewable energy *** addition to traditional high-efficiency devices(e.g.,turbines and watermills),the micro-power extracting technologies based on the flow-induced vibration(FIV)effect have sparked great concerns by virtue of their prospective applications as a self-power source for the microelectronic devices in recent *** article aims to conduct a comprehensive review for the FIV working principle and their potential applications for energy ***,various classifications of the FIV effect for energy harvesting are briefly introduced,such as vortex-induced vibration(VIV),galloping,flutter,and wake-induced vibration(WIV).Next,the development of FIV energy harvesting techniques is reviewed to discuss the research works in the past three *** application of hybrid FIV energy harvesting techniques that can enhance the harvesting performance is also ***,the nonlinear designs of FIV-based energy harvesters are reported in this study,e.g.,multi-stability and limit-cycle oscillation(LCO)***,advanced FIV-based energy harvesting studies for fluid engineering applications are briefly ***,conclusions and future outlook are summarized.

关键词： vibration-driven energy harvesting flow-induced vibration(FIV) piezoelectric approach nonlinear design

Sub-nanometer finishing of polycrystalline tin by inductively coupled plasma-assisted cutting

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Frontiers of mechanical engineering 2023年第3期18卷 233-249页

作者： Peng LYU Min lai Yifei SONG Zhifu XUE Fengzhou FANG State Key Laboratory of Precision Measuring technology&Instruments Laboratory of MicroNano Manufacturing TechnologyMNMTTianjinUniversityTianjin300072China Centre of MicroNano Manufacturing technology-MNMT-Dublin School of Mechanical&Materials EngineeringUniversity College DublinDublin4Ireland

Polycrystalline tin is an ideal excitation material for extreme ultraviolet light ***,the existence of grain boundary(GB)limits the surface roughness of polycrystalline tin after single-point diamond turning(SPDT).In this work,a novel method termed inductively coupled plasma(ICP)-assisted cutting was developed for the sub-nanometer finishing of polycrystalline *** relationship between ICP power,processing time,and modification depth was established by thermodynamic simulation,and the fitted heat transfer coefficient of polycrystalline tin was 540 W/(m2·K).The effects of large-thermal-gradient ICP treatment on the microstructure of polycrystalline tin were *** 0.9 kW ICP processing for 3.0 s,corresponding to the temperature gradient of 0.30 K/μm,the grain size of polycrystalline tin was expanded from a size of approximately 20-80μm to a millimeter *** Taguchi method was used to investigate the effects of rotational speed,depth of cut,and feed rate on *** conducted based on the ICP system indicated that the plasma-assisted cutting method promoted the reduction of the influence of GB steps on the finishing of polycrystalline tin,thereby achieving a surface finish from 8.53 to 0.80 nm in *** results of residual stress release demonstrated that the residual stress of plasma-assisted turning processing after 504 h stress release was 10.7 MPa,while that of the turning process without the ICP treatment was 41.6 MPa.

关键词： plasma-assisted cutting polycrystalline tin single-point diamond turning surface roughness