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Analysis of complex intermittency in Boost converter from a bifurcation control viewpoint

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Science in China(Series F) 2008年第12期51卷 2135-2149页

作者： ZHOU YuFei JIANG XueDong chen junning School of Electronic Science and Technology Anhui University Hefei 230039 China

Due to undesirable interference via unintended coupling paths, switching converters may exhibit complex intermittency, which appears as a form of bifurcation undergoing regular operation, subharmonics, and chaos orderly and repeatedly for a long period of time. Such intermittent operation, being an unwanted operating state, should normally be avoided in power converters. This paper expounds the mechanism and conditions for the emergence of intermittency in a common current-mode controlled Boost converter. It is found that interference at frequencies near the switching frequency or its rational multiples may induce intermittent operation. The strengths and frequencies of the interfering signals determine the type and period of intermittency. The problem is analyzed by transforming the time-bifurcation analysis to a conventional parameter-bifurcation analysis. Based on this transformation, intermittency can be investigated from the bifurcation control viewpoint. Furthermore, the critical circuit parameter conditions for the emergence of intermittency can be predicted and compared with those from circuit simulation.

关键词： power converter intermittency bifurcation bifurcation control

Recent advances in quantifying the inactive lithium and failure mechanism of Li anodes in rechargeable lithium metal batteries

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Journal of Energy Chemistry 2024年第9期96卷 226-248页

作者： Mingming Tao junning chen Hongxin Lin Yingao Zhou Danhui Zhao Peizhao Shan Yanting Jin Yong Yang State Key Laboratory for Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials and Department of ChemistryCollege of Chemistry and Chemical EngineeringTan Kah Kee Innovation Laboratory(IKKEM)Xiamen UniversityXiamen 361005FujianChina School of Engineering Westlake UniversityHangzhou 310024ZhejiangChina School of Energy Research Xiamen UniversityXiamen 361005FujianChina

Lithium metal is considered as the ultimate anode material for the next generation of high-energy density ***,non-uniform lithium dendrite growth,serious electrolyte consumption,and significant volume changes during lithium deposition/stripping processes lead to sustained accumulation of inactive lithium and poor cycling *** the formation and evolution of inactive lithium under different conditions and fully evaluating the complex failure modes are the key issues in this challenging *** article comprehensively reviews recent research progress on the quantification of formation and evolution of inactive lithium detected by different quantitative techniques in rechargeable lithium metal *** key research challenges such as failure mechanism,modification strategies and operando characterization of lithium metal anodes are systematically summarized and *** review provides a new angle of view to understand failure mechanism of lithium metal anodes and inspiration and guidance for the future development of rechargeable lithium metal batteries.

关键词： Lithium metal anodes Inactive lithium Quantitative technique Failure mechanism

Principle of designing slope compensation in PFC Boost converter

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Science in China(Series F) 2009年第11期52卷 2226-2233页

作者： ZHOU YuFei HUANG Jiacheng WANG ShiBing JIANG Wei chen junning School of Electronic Science and Technology Anhui University Hefei 230039 China

Due to wide input fluctuation with line frequency of 50 Hz, power-factor-correction （PFC） Boost converters tend to exhibit fast-scale instability over time domain. The traditional remedy is to impose slope compensation so as to weaken or eliminate this instability. A theoretical principle on the implementation of slope compensation signal is still lacking. Empirical design will induce over compensation frequently, resulting in a large decrease of power factor. In order to tackle this issue, by constructing the discrete-time iterative map of the PFC Boost converter from the viewpoint of bifurcation control theory of nonlinear systems, consequently, the criterion of critical stability for the PFC circuit can be established. Based on this stability criterion, appropriate design of slope compensation can be achieved. Our work indicates that 3 main circuit parameters （i.e. switching cycle, output reference voltage and inductor） determine the effective amplitude design of the slope compensation signal. The results, validated by a large quantity of analytical and numerical studies, show that appropriate slope compensation can be effective in weakening （or controlling） fast-scale bifurcation while maintaining a rather high input power factor.

关键词： PFC Boost converter peak current mode control slope compensation fast-scale bifurcation bifurcation control

Physical mechanism of resistance switching in the co-doped RRAM

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Journal of Semiconductors 2017年第1期38卷 100-105页

作者： Jin Yang Yuehua Dai Shibin Lu Xianwei Jiang Feifei Wang junning chen Department of Research Hefei Normal University School of Electronics and Information Engineering Anhui University

The physical mechanism of the resistance switching for RRAM with co-doped defects（Ag and oxygen vacancy）is studied based on the first principle calculations and the simulation tool VASR The interaction energy,formation energy and density of states of Ag and oxygen vacancy defect（VO）are *** calculated results reveal that the co-doped system is more stable than the system only doped either Ag or VO defect and the impurity energy levels in the band gap are contributed by Ag and VO *** obtained partial charge density confirmed further that the clusters are obvious in the direction of Ag to Hf ions,which means that it is Ag but VO plays a role of conductive *** the formation mechanism,the modified electron affinity and the partial charge density difference are *** results show that the ability of electron donors of Ag is stronger than VO In conclusion,the conductivity of the physical mechanism of resistance switching in the co-doped system mainly depends on the doped Ag.

关键词： RRAM resistive switching co-doped conductive path physical mechanism

Effect of high temperature annealing on the performance of MANOS charge trapping memory

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Science China(Technological Sciences) 2012年第4期55卷 888-893页

作者： JIN Lin ZHANG ManHong HUO ZongLiang YU ZhaoAn JIANG DanDan WANG Yong BAI Jie chen junning LIU Ming Institute of Microelectronics Chinese Academy of SciencesBeijing 100029China School of Electronics and Information Engineeing Anhui UniversityHefei 230039China

We have investigated the effect of post deposition annealing (PDA) temperature of Al2O3 blocking layer on the performance of charge trapping memory capacitors. Two splits of PDA were performed in N2 ambient at 850°C/60 s and 1050°C/60 s, respectively. The 1050°C annealed capacitor could be programmed and erased normally by using Fowler-Nordheim (FN) injection. In contrast, the 850°C annealed device could not be erased, even though it could be programmed properly. By measuring the gate leakage current and the flatband voltage shift, we found the erase failure in the 850°C annealed device was due to a larger gate back-injection leakage current at Vg<0. The trend of gate leakage current was further verified in two Al/Al2O3/SiO2/p-Si control capacitors with the same PDA splits. In addition, constant voltage stress measurements on control capacitors in the FN regime showed that the change of gate leakage current followed an empirical Curie-von Schweidler law at Vg<0. The data pointed out the importance to further study the relation between PDA conditions and the defect generation properties in Al2O3 blocking layer.

关键词： charge trapping memory Al2O3 traps annealing

Approaches for improving the performance of filament-type resistive switching memory

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Chinese Science Bulletin 2011年第4期56卷 461-464页

作者： LIAN WenTai LONG ShiBing LU HangBing LIU Qi LI YingTao ZHANG Sen WANG Yan HUO ZongLiang DAI YueHua chen junning LIU Ming Laboratory of Nano-Fabrication and Novel Device Integration Institute of Microelectronics Chinese Academy of Sciences Beijing 100029 China College of Electronics and Technology Anhui University Hefei 230039 China

Resistive random access memory (RRAM) has received significant research interest because of its promising potential in terms of down-scaling,high density,high speed and low power. However,its endurance,retention and uniformity are still imperfect. In this article,the physical mechanisms of filament-type RRAM and the approaches for improving the switching performance,including doping,process optimization and interface engineering,are introduced.

关键词：开关性能记忆体电阻式灯丝随机存取物理机制界面工程工艺优化

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一种新型MEMS加速度计温度补偿方法研究

传感技术学报 2015年第1期28卷 39-42页

作者：郑长勇陈军宁安徽建筑大学电子与信息工程学院合肥230601 安徽大学电子信息工程学院合肥230601

为降低环境温度对加速度计测量输出的影响,本文提出了一种新的加速度计温度补偿方法,即三维拟合曲面和计算的补偿方法。本文详细介绍了该温度补偿方法的具体原理和实现方法,并用实验进行了验证,实验结果表明加速度计最大零位漂移由温度... 详细信息

为降低环境温度对加速度计测量输出的影响,本文提出了一种新的加速度计温度补偿方法,即三维拟合曲面和计算的补偿方法。本文详细介绍了该温度补偿方法的具体原理和实现方法,并用实验进行了验证,实验结果表明加速度计最大零位漂移由温度补偿前的500 m V缩小为温度补偿后的50 m V,即温漂缩小了一个数量级,补偿效果明显。

关键词： MEMS 加速度计温度补偿最小二乘法

Role of Mechanical Stimuli in Oral Implantation

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Journal of Biosciences and Medicines 2014年第4期2卷 63-68页

作者： Wei Li Daniel Lin junning chen Zhongpu Zhang Zhipeng Liao Michael Swain Qing Li School of Aerospace Mechanical and Mechatronic Engineering The University of Sydney Sydney Australia

Prosthetic implantation has been a prevalent surgical procedure in dentistry. Insertion of dental implant significantly changes local oral conditions and leads to the surrounding bone to remodel to a new morphology. To predict how the bone responds such a biomechanical change, finite element analysis (FEA) based remodeling simulation has proven effective. For a range of mechanical stimuli, which should be used remains controversial arguable? This paper aims to compare how the different mechanical stimuli, including mechostat model (effective strain), daily stress and strain energy density (SED) affect the predictions of bone remodeling.

关键词： Dental Implant Bone Remodeling Mechanobiology Finite Element Mechanical Stimulus

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CMOS低电压高性能混频器的设计

仪器仪表学报 2006年第Z3期27卷 2015-2017页

作者：洪琪陈军宁柯导明潘灏安徽大学电子科学与技术学院合肥230039

随着CMOS RFIC的快速发展,使得射频、中频和基带集成在同一块芯片中成为可能。在无线局域网的RF前端电路中,混频器是非常重要的部分,它影响相邻电路和接收机的整体性能。本论文的主要工作是在吉尔伯特混频器(Gilbert Cell Mixer)的原型... 详细信息

随着CMOS RFIC的快速发展,使得射频、中频和基带集成在同一块芯片中成为可能。在无线局域网的RF前端电路中,混频器是非常重要的部分,它影响相邻电路和接收机的整体性能。本论文的主要工作是在吉尔伯特混频器(Gilbert Cell Mixer)的原型上,引入了一种新的低电压结构和新的跨导单元结构设计了一种可以工作在低电压下具有优良性能的新型混频器。

关键词：混频器射频低电压高增益