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Electro-peroxone degradation of diethyl phthalate: Cathode selection, operational parameters, and degradation mechanisms

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Journal of hazardous materials 2016年 319卷 61-8页

作者： Meifang Hou Yaofei Chu Xiang Li Huijiao Wang Weikun Yao Gang Yu Seiichi Murayama Yujue Wang School of Ecological Technology and Engineering Shanghai Institute of Technology Shanghai 201418 China. School of Ecological Technology and Engineering Shanghai Institute of Technology Shanghai 201418 China School of Environment Beijing Key Laboratory for Emerging Organic Contaminants Control State Key Joint Laboratory of Environmental Simulation and Pollution Control Tsinghua University Beijing 100084 China. School of Environment Beijing Key Laboratory for Emerging Organic Contaminants Control State Key Joint Laboratory of Environmental Simulation and Pollution Control Tsinghua University Beijing 100084 China. Power and Industrial Systems R&D Center Toshiba Corporation Fuchu-shi Tokyo Japan. School of Environment Beijing Key Laboratory for Emerging Organic Contaminants Control State Key Joint Laboratory of Environmental Simulation and Pollution Control Tsinghua University Beijing 100084 China. Electronic address: wangyujue@***.

This study compares the degradation of diethyl phthalate (DEP) by the electro-peroxone (E-peroxone) process with three different carbon-based cathodes, namely, carbon-polytetrafluorethylene (carbon-PTFE), carbon felt, and reticulated vitreous carbon (RVC). Results show that the three cathodes had different electrocatalytic activity for converting sparged O2 to H2O2, which increased in order of carbon felt, RVC, and carbon-PTFE. The in-situ generated H2O2 then reacts with sparged O3 to yield OH, which can in turn oxidize ozone-refractory DEP toward complete mineralization. In general, satisfactory total organic carbon removal yields (76.4-91.8%) could be obtained after 60min of the E-peroxone treatment with the three carbon-based cathodes, and the highest yield was obtained with the carbon-PTFE cathode due to its highest activity for H2O2 generation. In addition, the carbon-PTFE and carbon felt cathodes exhibited excellent stability over six cycles of the E-peroxone treatment of DEP solutions. Based on the intermediates (e.g., monoethyl phthalate, phthalic acid, phenolics, and carboxylic acids) identified by HPLC-UV, plausible reaction pathways were proposed for DEP mineralization by the E-peroxone process. The results of this study indicate that carbon-based cathodes generally have good electrocatalytic activity and stability for application in extended E-peroxone operations to effectively remove phthalates from water.

关键词： Electrocatalytic ozonation Electrode Hydrogen peroxide Ozone Phthalates

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Research of algorithm and analysis of performance for DC surge impedance relay

Research of algorithm and analysis of performance for DC sur...

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12th IET International Conference on Developments in power System Protection, DPSP 2014

作者： Lei, Aoyu Dong, Xinzhou State Key Lab of Control and Simulation of Power Systems and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing 10084 China

Surge Impedance Relay(SIR) is applied to DC system. Characteristics of SIR in DC line are analysed. A DC SIR algorithm implementing wavelet transform applied to HVDC line protection is proposed. The feasibility of DC ... 详细信息

ISBN: (纸本)9781849198349

关键词： Wavelet transforms

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Experimental investigation and analysis of some common faults for wind turbine 68

Experimental investigation and analysis of some common fault...

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68th Society for Machinery Failure Prevention Technology Conference: Technology Solutions for Affordable Sustainment, MFPT 2014

作者： Yang, Wenguang Li, Shaohua Jiang, Dongxiang State Key Laboratory of Control and Simulation of Power System and Generation Equipments Department of Thermal Engineering Tsinghua University Beijing100084 China

This paper focus on the fault characteristic by experimental research. A test rig is built for the direct driving stall fix-pitch horizontal axis wind turbine. 8 signals are collected by the experiment system, including wind speed, rotor rotational speed, shaft torque, the output electric power, vertical and horizontal vibration displacement of main shaft, vibration acceleration of the front bearing pedestal and the back bearing pedestal. 11 common wind turbine faults are researched by experiment. These faults are rotor mass imbalance, pneumatic asymmetry, airfoil changed, yaw fault, shaft horizontal misalignment, shaft vertical misalignment, front bearing pedestal looseness, rear bearing pedestal looseness, front bearing outer ring fault, front bearing inner ring fault, and front bearing roller fault. Several signal analysis methods, which are waveform analysis, orbit analysis, amplitude domain analysis, frequency domain analysis and envelope spectrum analysis, are adopted to extract characteristics from vibration signals. The influence on output power and vibration characteristics of these faults is presented by comparing with normal operation. The findings can be used to guide wind turbine fault diagnosis in engineering applications.

关键词： Wind

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Optimal reactive power compensation configuration in distribution power system integrated with small hydro power plant

Optimal reactive power compensation configuration in distrib...

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3rd International Conference on Energy and Environmental Protection, ICEEP 2014

作者： Ma, Hong Liang Ren, Zheng Mou Lu, Wen Xin Han, Yu Xin Wang, Zhao Jian Chen, Lai Jun Shaanxi Regional Electric Power Group Co. Ltd Xi'an 710061 China State Key Laboratory of Control and Simulation of Power System and Generation Equipment Department of Electrical Engineering Tsinghua University 100084 Beijing China

ISBN: (纸本)9783038351368

Hydropower is the most widely used renewable energy for electricity generation in China, and small hydro power plant (SHPP) is a flexible way of electricity generation in water-rich remote area. Voltage at the end of distribution network may be increased over the acceptable range due to the connection of SHPPs. Magnetic control reactor (MCR) is usually used to reduce the voltage by consuming reactive power. A mathematical model for calculation of the optimal capacity of MCR is proposed in this paper, and particle swarm optimization (PSO) is adopted to solve the optimization problem. Two cases based on the IEEE 33-bus test system are used to validate the proposed method. In the given cases, system voltage is adjusted to the acceptable range. © (2014) Trans Tech Publications, Switzerland.

关键词： Reactive power

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The bandwidth of instrument current transformer for fault detection in distribution networks

The bandwidth of instrument current transformer for fault de...

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12th IET International Conference on Developments in power System Protection, DPSP 2014

作者： Jiang, Bo Dong, Xinzhou Shi, Shenxing Wang, Bin Bak, Dominik State Key Lab of Control and Simulation of Power Systems and Generation Equipments Dept. of Electrical Engineering Tsinghua University Haidian District Beijing 100084 China

ISBN: (纸本)9781849198349

The distribution network detection devices are generally using two kinds of instrument current transformer (ICT), of which one is used to transform the travelling wave and transient signals, while the other is used to transform the power frequency signals. Such scheme is neither necessary nor economical. This paper analyses the influences of sampling resistance, stray capacitance and magnetizing inductance on the frequency characteristic of ICT. Considering that fault zero sequence transient current has big transient component and small power frequency component, an ICT with wide band frequency accuracy has been chosen. Practical experiments have been done. The technical parameters given by the instrument factory are only within 20-20kHz. The characteristics in higher frequency are seldom reported due to the lack of test means. The experiments in this paper is based on the transient tester instrument and current amplifiers developed by our laboratory, which can output wide frequency band current within 20Hz-100kHz up to 50A. Experiment shows that, the predicted results were in good agreement with the measured ones.

关键词： Electric instrument transformers

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Travelling wave sampling data sharing solution in distribution substation based on IEC61850

Travelling wave sampling data sharing solution in distributi...

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12th IET International Conference on Developments in power System Protection, DPSP 2014

作者： Ni, Jiang Wang, Bin Dong, Xinzhou State Key Lab of Control and Simulation of Power Systems and Generation Equipments Dept. of Electrical Engineering Tsinghua University Haidian District Beijing 100084 China

ISBN: (纸本)9781849198349

The signal of travelling wave has the merit of immunity to system oscillation, transition resistance, CT saturation and the neutral point operation modes;it has been widely applied in field of fault detection and protection. Especially in isolated neutral grounded wind farm distribution network, the algorithm using multiple-bay travelling wave's information can exclusively achieve the fast fault feeder selection and tripping. However, travelling wave sampling frequency tends to reach 500 to 1000 times of that in algorithms with power frequency signal. The direct of travelling wave sampling data sharing in process bus would produce the communication block, and weaken the security of whole substation automation. To solve this problem, the performance of communication in process bus is theoretically analyzed and simulated in this paper, the communication requirement of travelling waves is quantified, and then a feasible scheme is proposed with data pre-processing and fault characteristic abstraction moving forward into the merging unit. simulations prove its validity. The work in paper can promote the wide application of travelling waves in substation based on IEC61850.

关键词： Merging

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Probabilistic substation fault diagnosis considering instrumentation channels and heterogeneous information: A unified Bayesian network model

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Qinghua Daxue Xuebao/Journal of Tsinghua University 2014年第10期54卷 1384-1390页

作者： Mu, Jianan Sun, Hongbin Wu, Wenchuan Guo, Qinglai Zhang, Boming State Key Laboratory of Control and Simulation of Power Systems and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing100084 China

Fault diagnosis plays an important role in improving power network troubleshooting capability. Conducting local fault diagnosis in substations can make full and quick use of abundant local information. A substation fault diagnosis method was presented based on Bayesian network to adapt to a wealth of information and distributed autonomy under smart grid environment. The method is effective in dealing with uncertainties induced by malfunctions of protection relays and circuit breakers as well as instrumentation channel errors. Heterogeneous information available in substations, such as sequence of events (SOEs), wave records and blocking signals, was also integrated into the method, with the junction tree algorithm used to conduct probabilistic reasoning. The results show that breaker SOEs can be better utilized when considering instrumentation channels. Furthermore, introduction of wave records and blocking signals can significantly improve diagnosis accuracies. ©, 2014, Press of Tsinghua University. All right reserved.

关键词： Bayesian networks

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A novel protection scheme for two-phase faults in power distribution system with neutral ungrounded

A novel protection scheme for two-phase faults in power dist...

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12th IET International Conference on Developments in power System Protection, DPSP 2014

作者： Shi, Shengxing Lei, Aoyu Li, Xin Dong, Xinzhou State Key Lab of Control and Simulation of Power Systems and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing 10084 China Shibei Power Supply Company Shanghai Municipal Electric Power Company Shanghai China

ISBN: (纸本)9781849198349

A novel protection scheme for two-phase faults in power distribution system with neutral ungrounded is presented. The feasibility of tripping single-phase circuit when a phase-tophase or two-phase-to-ground fault occurs is studied with induction motor loads as the focus. The paper at first analyses the effect of a induction motor runs with one phase cut off theoretically. And then a real power distribution system model with 110kV, 35kV and 6kV voltage levels is built in PSCAD/EMTDC. Three feasibility criteria are proposed for motors in continuous operation with single-phase opened. At last, the novel protection scheme is testified in simulation with protection time and reclosing time as variables respectively. The results verify that the scheme is feasible and power supply reliability is improved.

关键词： Induction motors

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Characteristics calculation and pattern recognition for partial discharge of cable joint

Characteristics calculation and pattern recognition for part...

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2014 International Conference on Communication Technology and Application, CTA 2014

作者： Xia, Y.F. Gui, J.F. Chen, X.Y. Gao, S.Y. Huang, J.H. Lin, J.H. Dongguan Power Breuse of Guangdong Grid China School of Electrical Engineering Beijing Jiaotong University China Department of Electrical Engineering Tsinghua University State Key Lab of Control and Simulation of Power Systems and Generation Equipments China

ISBN: (纸本)9781845649302

For PD pattern recognition, six kinds of typical cable fault models are made and tested. Characteristics are calculated from test data. Multiple statistical characteristics of PD distribution map are calculated and pattern vectors are formed. Artificial neural network is trained for recognition. Through the selection and adjustment of characteristics and network parameters, recognition effect with satisfactory result is obtained. © 2014 WIT Press.

关键词： Partial discharges

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Development of a frequency dependent network equivalent based RTDS-TSA hybrid transient simulation platform with heterogeneous architecture

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Dianli Xitong Zidonghua/Automation of Electric power systems 2014年第16期38卷 88-93页

作者： Hu, Yizhong Wu, Wenchuan Zhang, Boming Department of Electrical Engineering Tsinghua University Beijing100084 China State Key Laboratory of Control and Simulation of Power Systems and Generation Equipments Tsinghua University Beijing100084 China

For the simulation of large-scale AC/DC hybrid systems, both the precision of the DC parts and the efficiency of the whole system should be considered. Thus a real-time hybrid transient simulation platform is proposed by combining the real-time digital simulator (RTDS) and a transient stability analysis (TSA) program. A latest GTFPGA card is used to realize the high speed digital communication between RTDS and the computer deploying TSA program. Moreover, the frequency dependent network equivalent (FDNE) is implemented in this simulation platform to improve the accuracy of simulation results. By simulating a modified New England 39-bus test system incorporating high-voltage direct current (HVDC) components, the validity of the proposed simulation platform is verified.

关键词： Transient analysis

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