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Improved Hybrid Reactive Power Compensation System Based on FC and STATCOM and Its Control Method

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Chinese Journal of Electrical Engineering 2022年第2期8卷 29-41页

作者： Xiheng Liang fei jiang Xing peng Liansong Xiong Yongbin jiang Samir Gautam Zhichang Li School of Electrical and Information Engineering Changsha University of Science&TechnologyChangsha 410076China School of Electrical Engineering Xi’an Jiaotong UniversityXi’an 710049China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore 639798Singapore School of Electrical Engineering The University of SydneySydney NSW 2006Australia Beijing Sgitg-Accenture Information Technology Co. Ltd.Beijing 100080China

The purpose of this study is to solve the main problems in distribution networks,including increased line loss and reduced power supply quality caused by insufficient capacitive reactive *** reduce the capacity,voltage,and current stress of an active module of a compensation device and improve the cost performance of the device,an improved hybrid reactive power compensation system based on a fixed capacitor(FC)and a static synchronous compensator(STATCOM)is *** topological structure and basic operating principle of the proposed reactive power compensation system are *** addition,from the perspectives of output voltage,current,power,loss of the active part,and system compensation cost,the performances of the proposed reactive compensator and the inductively coupled STATCOM(L-STATCOM)are compared and ***,the key parameters of the proposed system are designed,and the joint optimization control strategy of the FC and STATCOM is *** correctness and effectiveness of the proposed topology structure and control method are verified by simulations.

关键词： Static synchronous compensator hybrid topology reactive power compensation fixed capacitor

Synthetic analysis of a two-ribbon microflare

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Research in Astronomy and Astrophysics 2010年第1期10卷 83-90页

作者： Cheng Fang peng-fei Chen Rong-Lin jiang Yu-Hua Tang Department of Astronomy Nanjing University Nanjing 210093 China

High-resolution Stokes spectral data of Hα, Ca Ⅱ 8542A, and Fe 16302.5A lines for a two-ribbon microflare （TRMF） were simultaneously obtained by the THEMIS telescope on 2002 September 5. We derive the intensity, velocity, and longitudinal magnetic field maps. The hard X-ray emission observed by RHESSI provides evidence of nonthermal particle acceleration in the TRMF. Using Ha and Ca Ⅱ 8542A line profiles and a non-LTE calculation, we obtain semi-empirical atmospheric models for the two brightest kernels of the TRME Our result indicates that the temperature enhancement in the chromosphere is more than 2500 K. The kinetic and radiative energies at the kernels are also estimated, resulting in an estimate of the total energy of the TRMF of about 2.4×10^29 erg. Observations indicate that the TRMF results from the low coronal magnetic reconnection following the eruption of a small fila- ment. However, the local temperature ＂bump＂ in the chromosphere presents a puzzle for such a standard flare model. A possible solution to this is discussed.

关键词： Sun chromosphere- Sun flares - Sun activity - Sun magnetic fields

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藏药大花黄牡丹根皮挥发油的提取和成分分析

黑龙江大学工程学报 2016年第3期7卷 63-67页

作者：蒋丽丽李鹏飞蒋帅张彦龙胡楠赵丹丹黑龙江大学生命科学学院哈尔滨150080 黑龙江大学黑龙江省普通高等学校分子生物学重点实验室哈尔滨150080 黑龙江大学医院哈尔滨150080

西藏大花黄牡丹（Paeonia ludlowii）为芍药科、芍药属植物,主要生长在海拔2 900～3 200 m的雅鲁藏布江红河谷和林缘坡麓次生灌木林。主要分析西藏大花黄牡丹根皮部挥发油成分。通过回流法对其挥发油组分进行提取,进行单因素影响实验摸... 详细信息

西藏大花黄牡丹（Paeonia ludlowii）为芍药科、芍药属植物,主要生长在海拔2 900～3 200 m的雅鲁藏布江红河谷和林缘坡麓次生灌木林。主要分析西藏大花黄牡丹根皮部挥发油成分。通过回流法对其挥发油组分进行提取,进行单因素影响实验摸索最适的提取条件,通过GCMS对其化学成分进行分析,采取面积归一法对成分相对含量进行分析。结果表明,大花黄牡丹根皮部挥发油最适提取为4倍水量,浸泡4 h,提取4 h,提取率为1.36%。通过GC-MS共检测出来22个化合物,其中最主要成分为丹皮酚。

关键词：挥发油藏药大花黄牡丹回流法 GC-MS

Optimization and verification of free flight separation similarity law in high-speed wind tunnel

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Chinese Journal of Aeronautics 2020年第2期33卷 501-507页

作者： fei XUE Xin JIN Peihua FENG Han QIN Zenghui jiang Yuchao WANG peng BAI China Academy of Aerospace Aerodynamics Beijing 100074China AVIC Chengdu Aircraft Design&Research Institute Chengdu 610091China Beijing Machinery and Electronics Engineering Institute Beijing 100074China

Based on the similarity of separation time,a similarity law optimization method for high-speed weapon delivery test is *** typical separation state under wind load is simulated by the numerical *** real separation data of aircraft,separation data of previous test methods,separation data of ideal wind tunnel test of previous methods,and simulation data of the proposed optimization method are obtained.A comparison of the data shows that the method proposed can improve the performance of *** law optimization starts with the development of motion equations and dynamic equations in the windless state to address the problems of mismatching between vertical and horizontal displacement,and to address the problems of separation trajectory distortion caused by insufficient gravity acceleration of the scaling model of existing light *** ejection velocity of the model is taken as a factor/vector,and is adjusted reasonably to compensate the linear displacement insufficiency caused by the insufficient vertical acceleration of the light model method,so as to ensure the matching of the vertical and horizontal displacement of the projectile,and to improve the consistency between the test results of high-speed projection and the actual separation *** optimized similarity law is applicable to many existing free-throwing modes of high-speed wind *** optimized similarity law is not affected by the ejection velocity and hanging mode of the *** optimized similarity law is suitable not only for the launching of the buried ammunition compartment and external stores,but also for the test design of projectile launching and gravity separation.

关键词： Carrier and missile interference Ejection separation Gravity separation High-speed weapon delivery Multi-body separation Similarity law optimization

Optimization and verification of wind tunnel free-flight similarity law for separation of cluster munition

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Chinese Journal of Aeronautics 2021年第3期34卷 61-70页

作者： fei XUE Jun TANG Huaqiang WANG Zenghui jiang Yuchao WANG Han QIN peng BAI China Academy of Aerospace Aerodynamics Beijing 100074China Hubei Aerospace Flight Vehicle Institute Wuhan 430048China Beijing Institute of Control Engineering Beijing 100036China

In view of the separation form of the separator from the back of the carrier upward and from the side of the carrier outward, separation-safety research is carried out by taking the separation of a cluster munition as an example. In previous wind tunnel free-flight tests, the similarity law of vertical, downward, moving submunition was used to design submunitions at different positions in different initial-velocity directions, which resulted in large discrepancies between wind tunnel test results and real flight. In a wind tunnel test, each submunition has an independent time-reduction ratio with respect to the dispenser. Even if the separation trajectory of a single submunition is accurate, there will be errors in the position of each submunition at a given time. Therefore, it is necessary to determine the time-reduction ratio between submunitions, and to modify the test results later. In order to ensure the accuracy of wind tunnel test results, the similarity law of a freeflight test in a wind tunnel is derived in this paper. The time-correction scheme to ensure motion similarity between submunitions is solved. Numerical simulation is used to simulate the separation of a wind tunnel test and real aircraft, and the motion parameters of different submunitions are solved. The results show that the new similarity laws derived for different types of submunitions can greatly reduce the errors caused by previous similarity laws. In addition to the case for the separation of a cluster munition, the similarity law can also be applied to the free-flight test design of wind tunnels for vertical separation and horizontal separation of other kinds of aircraft.

关键词： Cluster munition Ejection separation Free-flight wind tunnel test Multi-body separation Similarity-law derivation

Spatiotemporal Variation of Riverine Nutrients in a Typical Hilly Watershed in Southeast China Using Multivariate Statistics Tools

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Journal of Mountain Science 2015年第4期12卷 983-998页

作者： NIE Xiao-fei LI Heng-peng jiang Jia-hu DIAO Ya-qin LI peng-cheng State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences University of Chinese Academy of Sciences

The water quality of lakes can be degraded by excessive riverine *** water quality generally varies depending on region and season because of the spatiotemporal variations in natural factors and anthropogenic *** water quality measurements of eight water quality variables were analyzed for two years at 16 sites of the Tianmuhu *** variables were examined using hierarchical cluster analysis(HCA) and factor analysis/principal component analysis(FA/PCA) to reveal the spatiotemporal variations in riverine nutrients and to identify their potential *** revealed three geographical groups and three *** drainages comprising towns and large villages were the most polluted, six drainages comprising widely distributed tea plantations and orchards were moderately polluted, and eight drainages without the factors were the least *** river was most polluted in June when the first heavy rain(daily rainfall > 50 mm) occurs after fertilization and the number of rainy days is most(monthly number of rainy days > 20 days).Moderate pollution was observed from October to May, during which morethan 60% of the total nitrogen fertilizer and all of the phosphorus fertilizer are applied to the cropland, the total manure is applied to tea plantations and orchards, and a monthly rainfall ranging from 0 mm to 164 mm *** remaining months were characterized by frequent raining(i.e., number of rainy days per month ranged from 5 to 24) and little use of fertilizers, and were thus least ***/PCA identified that the greatest pollution sources were the runoff from tea plantations and orchards,domestic pollution and the surface runoff from towns and villages, and rural sewage, which had extremely high contributions of riverine nitrogen, phosphorus,and chemical oxygen demand, *** tea plantations and orchards promoted by the agricultural comprehensive development(ACD) were not environmentally *** nitrog

关键词： Nitrogen Phosphorus Chemical oxygen demand Spatial variation Temporal variation Water quality Fertilization Tianmuhu watershed

A kinetic study and factor analysis of solar thermochemical membrane reactors for syngas production

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Science China Technological Sciences 2025年第1期 207-221页

作者： Jiaxin XING Chao XU Xiangyu SUN Xin XIA fei JIN Qiongqiong jiang Jiale GAO Key Laboratory of Power Station Energy Transfer Conversion and System of MOE School of Energy Power and Mechanical EngineeringNorth China Electric Power University Department of Chemistry University College London School of Chemistry and Chemical Engineering Ningxia Key Laboratory of Solar Chemical Conversion TechnologyState Ethnic Affairs CommissionNorth Minzu University

Solar thermochemical conversion technologies are promising for effectively utilizing solar energy by capturing the full spectrum of solar radiation. To overcome the challenges of low energy conversion efficiency and intermittency faced by solar thermochemical conversion, these technologies can be effectively integrated with membrane reactor technology. Although the performance of solar thermochemical membrane reactors has been experimentally tested, the chemical reactions and oxygen transport mechanisms during the energy conversion process remain poorly understood. This study introduces a resistance network model to elucidate the interactions between interfacial reactions and bulk diffusion during simultaneous oxidationreduction reactions on both sides of the membrane. We analyzed the oxygen flux of the membrane reactor under various operating conditions using this model to identify the reaction/transport-limiting side of the overall process. The most effective solar membrane reactor configuration utilizes natural gas and CO2, facilitating clean conversion of fossil fuels with significant advantages in fuel production and energy efficiency. Introducing CH4lowers the overall reaction temperature, maintains low oxygen partial pressure on the sweep side, and produces a synthesis gas with a 2:1 H2/CO molar ratio. Finally, a sensitivity analysis was used to explore the relationship between overall fuel production performance and operational parameters,highlighting the critical role of this research in enhancing the reaction and transport performance of membrane reactors and advancing the development of solar-driven thermochemical fuel production technologies.

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The Time-Dependent Von Kármán Shell Equation as a Limit of Three-Dimensional Nonlinear Elasticity

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Journal of Systems Science & Complexity 2021年第2期34卷 465-482页

作者： QIN Yizhao YAO peng-fei Department of Mathematical Science Tsinghua UniversityBeijing 100084China Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

The asymptotic behaviour of solutions of three-dimensional nonlinear elastodynamics in a thin shell is considered,as the thickness h of the shell tends to *** the appropriate scalings of the applied force and of the initial data in terms of h,it’s verified that three-dimesional solutions of the nonlinear elastodynamic equations converge to solutions of the time-dependent von Kármán equations or dynamic linear equations for shell of arbitrary geometry.

关键词： Nonlinear elasticity thin shell time-dependent von Kármán equations

Remote control of the recruitment and capture of endogenous stem cells by ultrasound for in situ repair of bone defects

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Bioactive Materials 2023年第3期21卷 223-238页

作者： Yanni He fei Li peng jiang feiyan Cai Qin Lin Meijun Zhou Hongmei Liu fei Yan Department of Ultrasound Institute of Ultrasound in Musculoskeletal Sports MedicineGuangdong Second Provincial General HospitalGuangzhou510317PR China The Second School of Clinical Medicine Southern Medical UniversityGuangzhou510515China Paul C.Lauterbur Research Center for Biomedical Imaging Institute of Biomedical and Health EngineeringShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen518055People’s Republic of China Center for Cell and Gene Circuit Design CAS Key Laboratory of Quantitative Engineering BiologyShenzhen Institute of Synthetic BiologyShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen518055People’s Republic of China

Stem cell-based tissue engineering has provided a promising platform for repairing of bone ***,the use of exogenous bone marrow mesenchymal stem cells(BMSCs)still faces many challenges such as limited sources and potential *** is important to develop new approach to effectively recruit endogenous BMSCs and capture them for in situ bone ***,we designed an acoustically responsive scaffold(ARS)and embedded it into SDF-1/BMP-2 loaded hydrogel to obtain biomimetic hydrogel scaffold complexes(BSC).The SDF-1/BMP-2 cytokines can be released on demand from the BSC implanted into the defected bone via pulsed ultrasound(p-US)irradiation at optimized acoustic parameters,recruiting the endogenous BMSCs to the bone defected or BSC *** by the daily p-US irradiation for 14 days,the alginate hydrogel was degraded,resulting in the exposure of ARS to these recruited host stem *** another set of sinusoidal continuous wave ultrasound(s-US)irradiation was applied to excite the ARS intrinsic resonance,forming highly localized acoustic field around its surface and generating enhanced acoustic trapping force,by which these recruited endogenous stem cells would be captured on the scaffold,greatly promoting them to adhesively grow for in situ bone tissue *** study provides a novel and effective strategy for in situ bone defect repairing through acoustically manipulating endogenous BMSCs.

关键词： Acoustically responsive scaffolds Biomimetic hydrogel scaffold complexes Endogenous stem cells Acoustic radiation force Bone defect repairing