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Chinese Journal of Catalysis 2017年第8期38卷 1413-1422页

作者： Mohsen Nikoorazm Farshid Ghorbani Arash Ghorbani-Choghamarani Zahra Erfani department of Chemistry Faculty of Science Ilam University P. O. Box69315516 Ilam Iran department of Environment Faculty of Natural Resource University of Kurdistan Sanandaj 66177‐15177 Iran

A Pd Schiff base complex was immobilized onto the surface of magnetic MCM‐41(Fe3O4@MCM‐41@Pd(0)‐P2C)as a novel,eco‐friendly,and recyclable heterogeneous nanocatalyst and fully characterized by FT‐IR,VSM,EDS,transmission electron microscopy,scanning electron microscopy,thermogravimetric analyses,ICP‐OES,and X‐ray powder diffraction *** Fe3O4@MCM‐41@Pd(0)‐P2C was investigated as a catalyst for the one‐pot Suzuki and Heck reactions in PEG as a green solvent to provide the target products in excellent *** main advantages of using this catalyst include a short reaction time,green reaction conditions,a simple experimental procedure,non‐use of hazardous organic solvents,low loading of the catalyst,and the ability to use various *** importantly,the catalyst could be easily separated from the reaction mixture with the assistance of an external magnet and could be recovered and reused several times without significant loss of stability and activity.

关键词： MCM‐41 Magnetic nanoparticles Suzuki reaction Heck reaction Polyethylene glycol (PEG) Palladium

A framework for stochastic estimation of electric vehicle charging behavior for risk assessment of distribution networks

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Frontiers in Energy 2020年第2期14卷 298-317页

作者： Salman HABIB Muhammad Mansoor KHAN Farukh ABBAS Muhammad NUMAN Yaqoob ALI Houjun TANG Xuhui YAN Key Laboratory of Control of Power transmission and Transformation of the Ministry of Education School of ElectronicInformation and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China department of electrical Engineering University of Engineering and TechnologyLahore 54890Pakistan State Grid Liyang Power Supply company Liyang 213300China

Power systems are being transformed to enhance the *** paper contributes to the knowledge regarding the operational process of future power networks by developing a realistic and stochastic charging model of electric vehicles(EVs).Large-scale integration of EVs into residential distribution networks(RDNs)is an evolving issue of paramount significance for utility *** voltages prevent effective and reliable operation of *** EV loads require a stochastic approach to predict EVs charging demand,consequently,a probabilistic model is developed to account several realistic aspects comprising charging time,battery capacity,driving mileage,state-of-charge,traveling frequency,charging power,and time-of-use mechanism under peak and off-peak charging *** attempt is made to examine risks associated with RDNs by applying a stochastic model of EVs charging *** output of EV stochastic model obtained from Monte-Carlo simulations is utilized to evaluate the power quality parameters of *** equipment capability of RDNs must be evaluated to determine the potential *** specifications of RDNs including voltage unbalance factor,voltage behavior,domestic transformer limits and feeder losses are assessed in context to EV charging scenarios with various charging power levels at different penetration ***,the impact assessment of EVs on RDNs is found to majorly rely on the type and location of a power network.

关键词： electric vehicles(EVs) residential distribution networks(RDNs) voltage unbalance factor(VUF) state-of charge(SOC) time-of-use(TOU)

Environment-friendly Insulating Gases for HVDC Gas-insulated transmission Lines

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CSEE Journal of Power and Energy Systems 2021年第3期7卷 510-529页

作者： Geng Chen Youping Tu Cong Wang Jue Wang Zhikang Yuan Guoming Ma Jian Wang Bo Qi Chuanyang Li State Key Laboratory of Alternate electrical Power System with Renewable Energy Sources and the Beijing Key Laboratory of High Voltage and EMC North China Electric Power UniversityBeijing 102206China Institute of electrical Engineering Chinese Academy of SciencesBeijing 100190China department of electrical Engineering Tsinghua UniversityBeijing 100084China

Environment-friendly gas insulating mediums adapted to a DC gas-insulated transmission line(GIL)electric field condition is the key to the next generation of Environment-friendly HVDC *** this paper,we review the literature on sulfur hexafluoride(SF6)alternatives including the scientific understanding,control,and implementation of gas-solid systems in this type of power ***,the structure-activity relationship between the molecular structure and physico-chemical properties of Environment-friendly insulating gases is ***,the search and prediction of important physicochemical properties of gases are ***,in view of the potential of environmental friendly insulating gases,the swarm parameters of gas discharge and breakdown properties in a quasi-uniform field,inhomogeneous field,and at the gas-solid interface,that need to be taken into account with industrialized DC GILs are *** latest research progress on insulation characteristics,especially the polarity effect in DC gas-solid insulation systems,the sensitivity to the electrode surface state,and the non-uniformity of the electric field,and the influence of metal particles and their variation with air pressure,is *** addition,the heat transfer characteristics of insulating gases,related to DC GIL transmission with a large current-carrying capacity and the influence of alternative gases on the heat transfer characteristics are ***,aiming at solving the contradiction of low environmental impact,high dielectric strength and low liquefaction temperatures in the selection of alternative gases,an coordinated regulation model for Environment-friendly gases in DC GILs is *** for future work on this topic are also presented.

关键词： Environmental friendly insulating gas gas-insulated transmission line high-voltage direct-current transmis-sion sulfur hexafluoride

A flutter-effect-based triboelectric nanogenerator for breeze energy collection from arbitrary directions and self-powered wind speed sensor

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Nano Research 2019年第12期12卷 3018-3023页

作者： Jie Hu Xianjie Pu Hongmei Yang Qixuan Zeng Qian Tang Dazhi Zhang Chenguo Hu Yi Xi department of Applied Physics State Key Laboratory of Power Transmission Equipment&System Security and New TechnologyChongqing UniversityChongqing 400044China

Triboelectric nanogenerators(TENGs)have been developed rapidly into an efficient wind energy collection *** the frictionwear and energy loss in breeze energy collection is a research direction worthy of ***,a flutter-effect-based triboelectricnanogen erator(FE-TENG)is designed to collect the breeze energy at low wind speed from arbitrary *** from previouswind-driven TENGs,the wind-driven part of this device is separated from the TENG units,which not only avoids the wear of friction layerscaused by direct wind contact but also reduces the energy loss,therefore,relatively stable electric outputs are obtained with Voc-281 V,Isc-13.4μA,Qsc-143 nC,and output power-4 mW at the wind speed of 4.5 m/s,*** addition,a real-time wind speed monitoringsystem based on LabVIEW software with high sen sitivity and fast response to wind is achieved relying on the excellent linear relation shipbetween wind speed and electrical output ***,it has been successfully applied as power sources for portable electronics,about 170 commercial light-emitting devices(LEDs)are lighted and a digital watch is successfully driven at the wind speed of 2.9 m/*** worknot only provides a new structure and idea for the future collection of clean and sustainable breeze energy from arbitrary directions but also hasgreat potential in the field of self-powered systems.

关键词： flutter effect triboelectric nanogenerator arbitrary directions wind speed sensor

Operational reliability evaluation of restructured power systems with wind power penetration utilizing reliability network equivalent and time-sequential simulation approaches

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Journal of Modern Power Systems and Clean Energy 2014年第4期2卷 329-340页

作者： Yi DING Lin CHENG Yonghong ZHANG Yusheng XUE School of Information and Control Nanjing University of Information Science&TechnologyNanjingChina department of electrical Engineering Technical University of DenmarkLyngbyDenmark department of electrical Engineering Tsinghua UniversityBeijingChina State Grid electric Power Research Institute NanjingChina

In the last two decades,the wind power generation has been rapidly and widely developed in many regions and countries for tackling the problems of environmental pollution and sustainability of energy ***,the high share of intermittent and fluctuating wind power production has also increased the burden of system operator for securing power system reliability during the operational ***,the power system restructuring and deregulation have not only introduced the competition for reducing cost but also changed the strategy of reliability evaluation and management of power *** conventional long-term reliability evaluation techniques have been well developed,which have been more focused on planning and expansion rather than operation of power *** paper proposes a new technique for evaluating operational reliabilities of restructured power systems with high wind power *** proposed technique is based on the combination of the reliability network equivalent and time-sequential simulation *** operational reliability network equivalents are developed to represent reliability models of wind farms,conventional generation and reserve provides,fast reserve providers and transmission network in restructured power systems.A contingency management schema for real time operation considering its coupling with the dayahead market is *** time-sequential Monte Carlo simulation is used to model the chronological characteristics of corresponding reliability network *** method is also developed in the simulation procedures for improving the computational *** proposed technique can be used to evaluate customers’reliabilities considering high penetration of wind power during the power system operation in the deregulated environment.

关键词： Operational reliability Restructured power system Wind power Simulation

Influence of Meteorological Parameters on Electromagnetic Environment of UHVDC transmission Line Under High Altitude Condition

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高电压技术 2012年第12期38卷 3177-3181页

作者： LIU Lei LI Min LI Ruihai YU Zhanqing LIUZhihong LIU Xiangshi electric Power Research Institute China Southern Power Grid Co. Ltd. Guangzhou 510080 China department of electrical Engineering Tsinghua University Beijing 100084 China Zhumadian electric Power company China State Grid Company Zhumadian 463000 China

Measuring the electromagnetic (EM) environment parameters of a transmission line in bad weather conditions (such as rain, wind, etc.) is difficult for technical staff. In the National Engineering Laboratory for UHV Technology (Kunming),a test line was completed for EM environment tests. An automated EM environment testing system was installed under the line, the radio interference (RI),audible noise (AN),resultant electric field strength(E_s),and ion current density (J_s) at ground level were measured under all weather conditions within a voltage range from ± 800 kV to ± 1 000 kV over two years. Based on the measurement results, the influence of meteorological parameters on the EM environment of the transmission line was studied. When the H_R increases from 40% to 80%, the RI, AN, E_s, Js would have different degrees of attenuation. The RI on a rainy day is 3 dB lower than that of a sunny day, while the Js gets a sharp increase with the same weather condition change. In addition, AN and E_s are greatly influenced by wind speed: with increasing wind speed, E_s decreases and AN becomes unstable.

关键词：电磁环境测试系统高压直流输电线路气象参数高海拔天气条件传输线路技术人员环境参数

In-situ measurement of the dissolved S^(2-) in seafloor diffuse flow system: sensor preparation and calibration

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第3期9卷 423-428页

作者： Ying YE Xia HUANG Yi-wen PAN Zhen-hua HAN Wei ZHAO department of Earth Sciences Zhejiang University Hangzhou 310027 China The State Key Laboratory of Fluid Power transmission ＆ Control Zhejiang University Hangzhou 310027 China

The preparation approach and calibration result of an improved type of ion selective electrode （ISE）, which is used to measure the total dissolved S^2-, are introduced in this paper. The improved Ag/Ag2S electrode uses silver wire as the substrate, which is surrounded by electric polymer containing superfine silver powder. After the stabilization of the epoxy-resin, Ag2S layer was formed by chemical reaction with 0.2 mol/L （NH4）2S solution for 5 min. With Ag/AgC1 as reference electrode, the Ag/Ag2S electrode can be used to measure dissolved S^2-. The correlation between the measured potentials and the logarithm of dissolved S^2- is found to be linear, within range of the concentration of dissolved S^2- from 10^-2-10-7 mol/L. The slope of the regression line between measured potential and logarithm of dissolved S^2- is about -27.7, which agrees well with the theoretical Nernst value -29.6. Furthermore, the performance of the improved Ag/Ag2S electrode, such as the response time, sensitivity and stability, greatly outweighs the conventional Ag/Ag2S electrode.

关键词： Solid Ag/Ag2S electrode Preparation approach Performance

Metal Particle Contamination in Gas-insulated Switchgears/Gas-insulated transmission Lines

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CSEE Journal of Power and Energy Systems 2021年第5期7卷 1011-1025页

作者： Jian Wang Qi Hu Yanan Chang Jingrui Wang Ruixue Liang Youping Tu Chuanyang Li Qingmin Li State Key Laboratory of Alternate electrical Power System with Renewable Energy Sources and the Beijing Key Laboratory of High Voltage and EMC North China Electric Power UniversityBeijing 102206China. department of electrical Engineering Tsinghua UniversityBeijing 100084China.

Metal particle contamination in a gas-insulated switchgear(GIS)or a gas-insulated transmission line(GIL)is an important factor leading to the decline of insulation *** the deterioration mechanism and suppression measures of metal particles on insulation is a key technical problem in enhancing the dielectric strength of GIS/GIL *** this paper,the charge and motion characteristics of metal particles are first *** gas gap breakdown caused by free metal particles and the surface flashover caused by metal particles near or adsorbed on the insulator are then analyzed according to different particle motion patterns and spatial *** in terms of operation managements,the existing methods of particle detection are *** addition,the main inhibition methods of metal particles are introduced from three aspects:particle trap,insulator surface treatment and electrode ***,the prospects in the future research on particle pollution in GIS/GIL are also pointed out.

关键词： Gas gap breakdown GIS/GIL metal particles particle detection particle suppression surface flashover

Guest Editorial:Advanced Materials for HVDC Insulation

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High Voltage 2020年第4期5卷 351-352页

作者： Du, Boxue Wang, Qing Tu, Youping Tanaka, Yasuhiro Li, Jin Institute of High Voltage School of Electrical and Information Engineering Tianjin University China Materials Science and Engineering Department of Materials Science and Engineering Pennsylvania State University United States department of electrical Engineering North China Electric Power University China Measurement and electric Machine Control Laboratory Tokyo City University Japan School of electrical and Information Engineering Tianjin University China

The rapid increase in both voltage level and capability of HVDC power transmission and transformation equipment poses great challenges to both integration and reliability of power *** insulation systems deployed along with these equipments have to withstand the severe electric field distortion,higher temperature rise and greater mechanical stress,*** insulation materials with unique comprehensive performance provide effective solutions to meet new ***,investigating the dielectric properties,determining the failure mechanisms,and exploring novel insulation materials become the core issues in developing more capable insulation systems.

关键词： insulation dielectric power

Pilot Protection Based on Amplitude Comparison for Renewable Power Teed Lines

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CSEE Journal of Power and Energy Systems 2022年第6期8卷 1519-1529页

作者： Ke Jia Zhe Yang Yu Fang Zhengxuan Zhu Liming Zheng Tianshu Bi Ali Hooshyar State Key Laboratory of Alternative electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China department of electrical and Computer Engineering University of TorontoTorontoON M5S 3G4Canada

Fault behaviors of inverter-interfaced renewable energy generators(IIREGs)are quite diverse from those of synchronous generators(SGs).They show the variable system impedance,the limited current and low inertia,so the proportional brake differential protection installed on the transmission line has a high risk of failure for phase-phase *** cope with this adaptive problem,a new pilot protection is proposed considering the huge differences in both current ***,an improved criterion is presented for a scenario with a teed *** existing protection principles focus excessively on the fault current characteristics of IIREGs,so they cannot operate correctly once IIREGs do not output their fault *** happens when IIREGs produce no power or the circuit breakers exactly reclose on permanent ***,the proposed method has good performance for the above *** proposed method only requires current amplitude information,and in this case the strict synchronizing measurement is not *** studies are performed under different fault conditions,and they confirm the proposed method has good performance under different fault ***,it is also verified using field-testing data.

关键词： Current amplitude inverter-interfaced renewable energy generators pilot protection teed line