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Coordinated Primary Frequency Regulation and Inertia Response Based on DFIG using Over Speed and Torque Reserve 36

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Coordinated Primary Frequency Regulation and Inertia Respons...

Preparation of Square and Labyrinth-Like TiO_2 Particles for Photo-Degradation of Organic Pollutants

第36届中国控制会议

作者： FENG Yantao XIE Zhen School of Electrical Engineering ＆ Automation Hefei Univ.Tech

ISBN: (纸本)9781538629185

large scale integration of wind farm combined to the grid is a tendency for the development of the new energy,which causingthe issue of low system *** analyzingthe mode of operation and the Maximum Power Point Tracking strategy（MPPT）of double fed induction generator（DFIG）,reviewing advantage and disadvantage of scholars’ works on inertia control in thepast few years,this paper proposed a new strategy to mode the DFIG,that is over speed and torque *** wind farm changes its electromagnetic power depending on the frequency of the gird,as a result,the reduced the drop of frequency and increase the inertia of the *** the other hand,the farm coordinates primary frequency regulation and avoids the second frequency *** paper builds a system with Simulink to validate the strategy,and the results confirmed its effectivenes s.

关键词： double fed induction generator virtual inertia over speed torque reserve

来源： cnki会议评论

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Acta Metallurgica Sinica(English Letters) 2014年第6期27卷 988-994页

作者： Yongjie Yan Shasha Zhang Guohua Jiang Xia Li Zhen Wei Wenxing Chen Junmin Wan Qixin Honours College Zhejiang Sci-Tech University Key Laboratory of Advanced Textile Materials and Manufacturing technology (ATMT) Ministry of EducationZhejiang Sci-Tech University Department of Materials Engineering Zhejiang Sci-Tech University

Square and labyrinth-like titanium dioxide particles were successfully synthesized by a simple hydrothermal method with assistant of halloysite nanotubes. The morphology and microstructure of as-prepared photo-catalysts were characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The photo-catalytic activity of as-prepared catalysts was evaluated by degradation of organic pollutants（Rhodamine B, methylene blue and methanol） under UV light irradiation.

关键词： Microstructure Photolysis Decomposition

POLYMER-SUPPORTED β-CYCLODEXTRIN CATALYST FOR SELECTIVE SYNTHESISOF 4-H YDROXYBENZOIC ACID

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Journal of Wuhan university of technology(Materials Science) 1996年第4期11卷 20-23页

作者：张胜民陆宇萍崔崇 Inst.of Mater.Sci.and tech..Wuhan univ.of tech..Wuhan 430070.China Huazhong university of Science and technology.Wuhan 430074.China

4-hydroxybenzoic acid was synthesized by one pot method using polymer-bonded β-aminopropionic acid-2-β-cyclodextrin as a *** which the selectivity for 4-hydroxybenzoic acid is 87%. A possible carboxylation mechanism... 详细信息

关键词： functional material polymer-supportedcatalyst β-cyclodextrin selective synthesis 4-hydroxybenzoic acid

THE DYADIC GREEN'S FUNCTION IN A LOADED RECTANGULAR WAVEGUIDE AND ITS APPLICATION

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Journal of Electronics(China) 1990年第4期7卷 317-325页

作者：喻志远 univ.of Elec.Sc.& tech. Chengdu

This paper presents a method to derive the Dyadic Green’s Function(DGF)ofa loaded rectangular waveguide by using the image *** the calculation of the DGF,we use the integral transformation and replace the multi-infinite summation by a single one;thus it greatly simplifies the calculation and saves computer *** an example of the DGF’sapplication,we give the moment method’s scattering field calculation of a metal sphere resting onthe broad wall of the loaded rectangular *** of our calculations well agree withboth data of experiments performed in our laboratory and those are *** is easy to seethat the method used in this paper can be expanded to other related waveguide problems.

关键词： Loaded waveguide Integral transformation Dyadic Green’s function

ON HIGH-POROUS CERAMIC FOR PHARMACEUTICAL CARRIER

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Journal of Wuhan university of technology(Materials Science) 1996年第4期11卷 14-19页

作者：孙淑珍邬江新周向勤陈安民王泰仪李振凡 Inst.of Mater.Sci.and tech..Wuhan univ.of tech..Wuhan 430070.China Tongji Hospital Tonji Medical UniversityWuhan 430013.P.R.China

A kind of hydroxyapatite (HA) high-porous ceramic (HPC) which is used as pharmaceutical carrier for spinal tuberculosis treating is investigated, the structure of HPC is analyzed and physicochemical properties are determined. Experiments and clinical application show that when HPC carrying antituberculosis drug was imbedded in the tuberculosis focus, the drug in effective concentration can continuously be released for 27 weeks, also, the drug concentration achieves high local level but low systematic level, thus the curative effect can distinctly enhanced.

关键词： high-porous ceramic hydroxyapatite pharmaceutical carrier spinal tuberculosis

Quantitative calculation for the dissipated energy of fault rock burst based on gradient-dependent plasticity

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Journal of university of Science and technology Beijing 2004年第3期11卷 197-201页

作者： Xuebin Wang Shuhong Dai Long Hai Department of Mechanics and Engineering Sciences, Liaoning technical university, Fuxin 123000, China Dept. of Mech. and Eng. Sci. Liaoning Tech. Univ. Fuxin 123000 China

The capacity of energy absorption by fault bands after rock burst wascalculated quantitatively according to shear stress-shear deformation curves considering theinteractions and interplaying among microstructures due to the heterogeneity of strain softeningrock materials. The post-peak stiffness of rock specimens subjected to direct shear was derivedstrictly based on gradient-dependent plasticity, which can not be obtained from the classicalelastoplastic theory. Analytical solutions for the dissipated energy of rock burst were proposedwhether the slope of the post-peak shear stress-shear deformation curve is positive or not. Theanalytical solutions show that shear stress level, confining pressure, shear strength, brittleness,strain rate and heterogeneity of rock materials have important influence on the dissipated *** larger value of the dissipated energy means that the capacity of energy dissipation in the formof shear bands is superior and a lower magnitude of rock burst is expected under the condition ofthe same work done by external shear force. The possibility of rock burst is reduced for a lowersoftening modulus or a larger thickness of shear bands.

关键词： rock burst heterogeneity dissipated energy plastic strain gradient post-peak stiffness characteristic length fault band strain softefiing

A high-resolution,hybrid compact-WENO scheme with minimized dispersion and controllable dissipation

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Science China(Physics,Mechanics & Astronomy) 2014年第5期57卷 971-982页

作者： SUN ZhenSheng HU Yu LUO Lei ZHANG ShiYing YANG ZhengWei Xi'an Research Institute of High-tech

In this paper, a high-resolution, hybrid compact-WENO scheme is developed based on the minimized dispersion and controllable dissipation reconstruction technique. Firstly, a sufficient condition for a family oftri-diagonal compact schemes to have independent dispersion and dissipation is derived. Then, a specific 4th order compact scheme with low dispersion and adjustable dissipation is constructed and analyzed. Finally, the optimized compact scheme is blended with the WENO scheme to form the hybrid scheme. Moreover, the approximation dispersion relation approach is employed to optimize the spectral properties of the nonlinear scheme to yield the true wave propagation behavior of the finite difference scheme. Several test cases are carried out to verify the high- resolution as well as the robust shock-capturing capabilities of the proposed scheme.

关键词： binaries: high-resolution schemes shock-capturing schemes nonlinear spectral analysis spectral optimization

Lie symmetries and conserved quantities for a two-dimentional nonlinear diffusion equation of concentration

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Chinese Physics B 2010年第1期19卷 30-34页

作者：赵丽傅景礼陈本永 Institute of Mathematical Physics Zhejiang Sci-Tech University Institute of Mechanical and Automation Control Engineering Zhejiang Sci-Tech University

The Lie symmetries and conserved quantities of a two-dimensional nonlinear diffusion equation ot concentration are considered. Based on the invariance of the two-dimensional nonlinear diffusion equation of concentration under the infinitesimal transformation with respect to the generalized coordinates and time, the determining equations of Lie symmetries are presented. The Lie groups of transformation and infinitesimal generators of this equation are obtained. The conserved quantities associated with the nonlinear diffusion equation of concentration are derived by integrating the characteristic equations. Also, the solutions of the two-dimensional nonlinear diffusion equation of concentration can be obtained.

关键词： Lie symmetry conserved quantity nonlinear diffusion equation of concentration

Density functional theory study of H, C and O chemisorption on UN(001) and(111) surfaces

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Nuclear Science and techniques 2014年第5期25卷 68-77页

作者：李如松何彬许鹏王飞马文彦 Xi’an Research Institute of Hi-tech

We performed density functional theory calculations of H, C, and O chemisorption on the UN(001) and(111) surfaces using the generalized gradient approximation(GGA) and the Hubbard U parameter and revised Perdew-Burke-Ernzerhof(RPBE) exchange-correlation functional at non-spin polarized level with the periodic slab model. Chemisorption energies vs. distance of molecules from UN(001) and UN(111) surfaces have been optimized for four symmetrical chemisorption sites, respectively. The results show that the Hollow, N-top, and Hollow adsorption sites are the most stable sites for H, C, and O atoms with chemisorption energies of 13.06,25.50 and 27.34 kJ/mol for UN(001) surface, respectively. From the point of adsorbent(UN(001) and UN(111)surfaces in this paper), interaction of O with the chemisorbed surface is of the maximum magnitude, then C and H, which are in agreement with electronegativities of individual atoms. For the UN(001) surface, U-N bond lengths change relatively little( 10%). Electronic structure calculations indicate that Bridge position is equivalent with Hollow position, and the most stable chemisorption position for H, C,and O atoms are all Bridge(or Hollow) position for the UN(111) surface. Calculated electronic density of states(DOSs) demonstrate electronic charge transfer between s, p orbitals in chemisorbed atoms and U 6d, 5f orbitals.

关键词：化学吸附能密度泛函理论联合国表面相互作用吸附位置广义梯度近似电子结构计算表