检索结果-内蒙古大学图书馆

Insight into the promotion mechanism of activated carbon on the monolithic honeycomb red mud catalyst for selective catalytic reduction of NO_(x)

引用

Frontiers of Environmental Science & Engineering 2021年第5期15卷 177-186页

作者： Qiuzhun Chen Xiang Zhang Bing Li Shengli Niu Gaiju Zhao Dong Wang Yue Peng Junhua Li Chunmei Lu John Crittenden National Engineering Laboratory for Coal-Burning Pollutants Emission Reduction School of Energy and Power EngineeringShandong UniversityJinan250061China Brook Byers Institute for Sustainable Systems and School of Civil and Environmental Engineering Georgia Institute of Technology828 West Peachtree StreetAtlantaGA30332USA State Key Joint Laboratory of Environment Simulation and Pollution Control National Engineering Laboratory for Multi Flue Gas Pollution Control Technology and EquipmentSchool of EnvironmentTsinghua UniversityBeijing100084China Energy Institute Qilu University of Technology(Shandong Academy of Sciences)Jinan250013China

Our previous study proved that the acid-pretreatment process could efficiently activate red mud(RM)for the selective catalytic reduction(SCR)of NO_(x).However,in terms of the molding process,which is the key step determining whether it can be applied in large-scale industrial,the surface acidity and reducibility of catalyst always decreased dramatically,and part of surface area and pore structure were *** this study,we prepared monolithic honeycomb red mud(MHRM)catalysts with activated carbon(AC)as an accelerant and investigated the effect of AC on the *** results showed that the MHRM with 3 wt.%of AC(MHRM-AC3)exhibited the best SCR performance,and kept more than 80%NO_(x)conversion in the range of 325℃–400℃.Compared with the MHRM,MHRM-AC1,and HMRM-AC5,the MHRM-AC3 has more mesoporous and macroporous structures,which can provide more adsorption active *** AC significantly improved NH3 adsorption and surface reducibility,which was mainly due to the increase of the surface acid sites(especially the Brönsted acid sites),the concentration of Fe(II),and the surface adsorbed *** presence of more Fe(Ⅱ)enriched the surface oxygen vacancies,as well as the surface adsorbed oxygen,due to the charge imbalance and unsaturated chemical *** surface adsorbed oxygen exhibited more active than lattice oxygen owing to its higher mobility,which was conducive to NO_(x)reduction in the SCR reaction.

关键词： Selective catalytic reduction Iron-based catalyst Red mud Monolithic catalyst Activated carbon

来源：评论

学校读者我要写书评

暂无评论

Mathematical models of the system-level safe operational areas of power electronic converters in plug-in hybrid electric vehicles

Mathematical models of the system-level safe operational are...

引用

作者： Wang, Xuesong Bai, Hua Zhao, Zhengming Yuan, Liqiang China Power Engineering Consulting Group Corporation Beijing 100011 China Kettering University Flint MI 48504 United States State Key Laboratory of Control and Simulation of Power System and Generation Equipment Tsinghua University Beijing 100084 China

With the development of plug-in hybrid electric vehicles (PHEVs), power electronics plays an increasingly important role in electric power train systems. The economic and reliable design of these power electronic systems, e.g., dc/ac inverter and battery charger, will be the inward search to popularize electric vehicles. As an extension of system-level safe operational areas (SSOAs) proposed in our previous literature, this paper details the criteria and mathematical models of SSOA for a battery charger and a three-phase two-level dc/ac inverter. Operational areas were established based on the SSOA. Thermal characteristics of the semiconductor devices, operational modes, and load characteristics were enclosed to enhance the mathematical models. Experiments on a 5-kW charger and a 55-kW/380-VAC inverter validated the effectiveness of SSOA. © 2011 IEEE.

关键词： Metals

来源：评论

学校读者我要写书评

暂无评论

Cerium-tungsten oxides supported on activated red mud for the selective catalytic reduction of NO_(x)

引用

Green Energy & Environment 2023年第1期8卷 173-182页

作者： Qiuzhun Chen Dong Wang Chuan Gao Bin Wang Shengli Niu Gaiju Zhao Yue Peng Junhua Li Chunmei Lu John Crittenden National Engineering Laboratory for Coal-Burning Pollutants Emission Reduction School of Energy and Power EngineeringShandong UniversityJinan250061China State Key Joint Laboratory of Environment Simulation and Pollution Control National Engineering Laboratory for Multi Flue Gas Pollution Control Technology and EquipmentSchool of EnvironmentTsinghua UniversityBeijing100084China Brook Byers Institute for Sustainable Systems and School of Civil and Environmental Engineering Georgia Institute of Technology828 West Peachtree StreetAtlantaGA30332United States Energy Institute Qilu University of Technology(Shandong Academy of Sciences)Jinan250013ShandongChina

Activated red mud(RM)has been proved to be a promising base material for the selective catalysis reduction(SCR)of *** inherent low reducibility and acidity limited its low-temperature *** this work,molybdenum oxide,tungsten oxide,and cerium oxide were used to reconfigure the redox sites and acid sites of red mud based *** activated red mud was reconfigured by cerium-tungsten oxide(Ce-W@RM),the NOx conversion kept above 90%at 219-480℃.The existence of Ce^(3+)/Ce^(4+) redox electron pairs provided more surface adsorbed oxygen(O_(α)) and served as a redox *** interactions between Ce,W species and Fe oxide in red mud occurred,which led to the formation of unsaturated chemical bond and promoted the activation of adsorbed NH_(3) ***_(3) and Ce_(2)(WO_(4))_(3)(formed by solid-state reaction between Ce and W species)could provide more Brønsted acid sites(W-O modes of WO_(3),W=O or W-O-W modes of Ce_(2)(WO_(4))_(3)).CeO_(2) species could provide more Lewis acid *** Langmuir-Hinshelwood(L-H)routes and Eley-Rideal(E-R)routes occurred in the low-temperature SCR reaction on the Ce-W@RM ***_(4)^(+) species on Brønsted acid sites,NH_(3) species on Lewis acid sites,bidentate nitrate and bridging nitrate species were key active intermediates species.

关键词： Air pollution control NOx Selective catalytic reduction Cerium Tungsten

来源：评论

学校读者我要写书评

暂无评论

A corrective security-constrained optimal power flow method for AC/DC hybrid systems based on MMC-HVDC

A corrective security-constrained optimal power flow method ...

引用

2017 IEEE Conference on Energy Internet and Energy System Integration, EI2 2017

作者： Lin, Yi Tang, Yu-Chen Qiu, Liu-Qing Zhang, Ming-Ye Ju, Yu-Tao State Grid Fujian Power Economic Research Institute Fuzhou China State Key Laboratory of Control and Simulation of Power Systems and Generation Equipments Tsinghua University Beijing China College of Information and Electrical Engineering China Agricultural University Beijing China

ISBN: (纸本)9781538614273

This paper presents an optimal power flow (OPF) model for AC/DC meshed networks with Modular Multilevel Converter based High Voltage Direct Current (MMC-HVDC) system. The OPF problem is formulated to minimize the total network loss of the whole AC/DC grids by adjusting generators and modular multilevel converters considering N-1 constraints and post-contingency corrective control. A practical method is proposed to handle N-1 static security constraints and corrective control with OPF more effectively. simulations are conducted on IEEE 39-bus testing system and a practical power grid. The results demonstrate the effectiveness of the approach. © 2017 IEEE.

关键词： Electric load flow

来源：评论

学校读者我要写书评

暂无评论

Research on low/high voltage ride through of PV grid-connected system based on control-hardware-in-the-loop

Research on low/high voltage ride through of PV grid-connect...

引用

2019 Tsinghua International Doctoral Forum

作者： Li, Shuang Si, Gangquan Qu, Kai He, Guoqing State Key Laboratory of Electrical Insulation and Power Equipment Shaanxi Key Laboratory of Smart Grid School of Electrical Engineering Xi'an Jiaotong University Xi'an Shaanxi Province China State Key Laboratory of Operation and Control of Renewable Energy and Storage Systems China Electric Power Research Institute Haidian District Beijing China

ISBN: (纸本)9781839533907

Fault ride-through capability is one of the important grid-connection indexes for large-scale generation of PV power and other renewable energy, which is of great significance for the safe and stable operation of the grid. In order to improve the fault ride-through capability of PV grid-connected inverter, a comprehensive control strategy of LVRT/HVRT of PV grid-connected inverter based on conventional control scheme is proposed in this paper. Meanwhile, the LVRT/HVRT test platform of PV grid-connected inverter was built by using the simulation technology of RT-LAB hardware-in-the-loop. Firstly, based on the eHS (electric hardware solver) technology of RT-LAB real-time simulation software, a set of PV grid-connected inverter semi-physical simulation system was built, mainly including PV simulator, PV inverter, filter circuit, three-phase controlled voltage source, etc. Then, according to the technical specification of PV grid-connected inverter, the fault ride-through control strategy of PV grid-connected inverter under the condition of voltage drop/rise symmetrically is proposed. Finally, the simulation tests of LVRT/HVRT were carried out on the simulation platform with the controller of PV inverter. simulation results show that the proposed control strategy meets the grid-connected requirements during LVRT/HVRT. In addition, it has good dynamic and static characteristics. © 2019 Institution of Engineering and Technology. All rights reserved.

关键词： simulation platform

来源：评论

学校读者我要写书评

暂无评论

Study on new leading-out mode of neutral points of large-sized turbo-generator

Study on new leading-out mode of neutral points of large-siz...

引用

International Conference on Electrical Machines and systems (ICEMS)

作者： L. Gui X.H. Wang Y.G. Sun W.J. Wang Department of Electrical Engineering State Key Laboratory of Control and Simulation of Power Systems and Generation Equipment Tsinghua University Beijing China

To supply overall protection for large-sized turbo-generator, a new approach about leading-out mode of neutral points and disposition of protection schemes is firstly presented in this paper. To check up the sensitivity of the new protection scheme, two turbo-generators with 300 MW are simulated using the multi-loop method. simulation results indicate the performance of the new protection scheme is much better than that of the traditional protection. Without adding hardware investment, the new leading-out mode is agreed by electrical machine designers.

关键词： power system protection Stator windings Current transformers power system simulation power generation Sun Laboratories power system control power systems Hardware

来源：评论

学校读者我要写书评

暂无评论

Research on the prediction-model of the surface-temperature of large oil-immersed power transformer

Research on the prediction-model of the surface-temperature ...

引用

International Conference on Electrical Machines and systems (ICEMS)

作者： H.Y. Wang P.S. Su X.H. Wang Department of Electrical Engineering State Key Laboratory of Control and Simulation of Power Systems and Generation Equipment Tsinghua University Beijing China

In order to detect the abnormal temperature of large oil-immersed power transformer earlier, this paper presents a new prediction-model of surface-temperature for the transformer to predict the normal surface-temperature. And to compare the difference between the predicted value and the measured value can judge if the condition of the transformer is fit to operate. The model parameters are estimated from the field data by using the partial-least-square method, which overcomes the instability of results estimated by using the traditional least-square method. Furthermore, the appropriate amount of data for the parameter estimation was decided according to the principle of heat transfer and the characteristics of the predicted deviation, such as mean, variance and normal distribution. The prediction model is verified from the accuracy of results predicted with one year of field data.

关键词： power transformers Oil insulation Temperature sensors Predictive models Parameter estimation Heat transfer Temperature measurement Thermal resistance power system simulation Surface fitting

来源：评论

学校读者我要写书评

暂无评论

Parameter calculation for induction machine rotor bar with non-sinusoidal current

Parameter calculation for induction machine rotor bar with n...

引用

International Conference on Electrical Machines and systems (ICEMS)

作者： Xinzhen Wu Xiangheng Wang Department of Electrical Engineering State Key Laboratory of Control and Simulation of Power Systems and Generation Equipment Tsinghua University Beijing China

ISBN: (纸本)7506274078

To evaluate the rotor bar parameters of an induction machine with the non-sinusoidal current, a new analysis approach, which employs the circuit analysis theory instead of electromagnetic field theory to count the skin effect, is proposed. In the presented method, a rotor bar is divided into many thin-layers with their own parameters derived. The superposition principle is proven for the calculation of total bar losses and slot magnetic energy due to the non-sinusoidal current composed of sinusoidal components with different frequencies, which shows the parameters of the bar can be expressed with the parameters at respective frequencies. For given examples, the parameters at different frequencies are calculated, and the results are verified by the analytical method or the finite element method.

关键词： Induction machines Skin effect Frequency Rotors Electromagnetic analysis Circuit analysis Magnetic losses Magnetic analysis Finite element methods power system simulation

来源：评论

学校读者我要写书评

暂无评论

Optimized design of main protection configuration scheme for internal faults of Shawan generator

Optimized design of main protection configuration scheme for...

引用

International Conference on Electrical Machines and systems (ICEMS)

作者： Yuguang Sun Xiangheng Wang Lin Gui Weijian Wang Department of Electrical Engineering State Key Laboratory of Control and Simulation of Power Systems and Generation Equipment Tsinghua University Beijing China

ISBN: (纸本)7506274078

In order to provide high-quality protection for large- and medium-sized generators, a new feasible method of designing main protection configuration scheme for internal faults of generators is desirable. Based on calculation of all the possible internal faults with the multi-loop method, the optimized design method is illustrated through Shawan generator in this paper. With this method, the optimal protection configuration scheme, composed of the split-phase transverse differential protection, two sets of incomplete longitudinal differential protection as well as one set of single element transverse differential protection, is determined for the internal faults of Shawan generator, which has two branches in each phase. The rate of operation and double-protection of the optimal scheme both reach the maximum. In addition to that, on all the possible phase-to-phase faults, at least two kinds of protection of the optimal scheme are sure to operate correctly. The optimized scheme excels the conventional one in protection performance index, which verifies the validity of the optimized method of designing main protection configuration scheme for generators.

关键词： Design optimization Circuit faults Design methodology power generation power system protection Character generation power system simulation Performance analysis Stators Sun

来源：评论

学校读者我要写书评

暂无评论

Calculation on the thermal field of the water cooling stator of three-Gorge hydro-generator

Calculation on the thermal field of the water cooling stator...

引用

International Conference on Electrical Machines and systems (ICEMS)

作者： H.Y. Wang P.S. Su X.H. Wang Department of Electrical Engineering State Key Laboratory of Control and Simulation of Power Systems and Generation Equipment Tsinghua University Beijing China

To simplify the calculation of winding bar temperature for the condition monitoring of the water cooling stator of Three-Gorge hydro-generator, this paper calculates three of two-dimension thermal fields. Using the three fields simulates the different section along the axial direction of the generator. The total amount of heat taken away by water can be calculated by weighting the result of three fields on the total axial length of them. Four groups of thermal-fields with different outlet-water temperature are calculated by using ANSYS multi-physical software. The calculation results of temperature of measurement-point between up-layer and down-layer bars in stator are partly supported by the measurement data. And the relatively error between the heat taken by cooling-water and the heat generated by the stator bar is always less than 5%

关键词： Cooling Stator cores Stator windings Solids Bars Heat transfer power system simulation Temperature Thermal engineering Condition monitoring

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：