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第十六届全国等离子体科学技术会议暨第一届全国等离子体医学研讨会

作者： Z.P.Zhang Z.F.Cheng J.Luo Z.J.Wang X.L.Zhang S.Y.Hou C.Cheng State Key Laboratory of Advanced Electromagnetic Engineering and Technology College of Electrical and Electronic EngineeringHuazhong University of Science and Technology

Introduction The importance about the edge plasma rotation is mainly shown in the L-H *** measurement by the passive spectroscopy of inherent impurity ions doesn't affect the plasma in *** it is chosen as a conventional diagnostic on *** a spectral diagnostic control system(SDCS) is developed to implement the automatic process of the edge rotation diagnostic system on J-TEXT tokamak.

关键词： The automatic control process of the edge rotation diagnostic system on J-TEXT tokamak

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Development of the current preamplifier for the radiation diagnostic on J-TEXT

Development of the current preamplifier for the radiation di...

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第十六届全国等离子体科学技术会议暨第一届全国等离子体医学研讨会

作者： S.Y.Hou Z.F.Cheng X.L.Zhang J.Luo Z.P.Zhang C.Cheng State Key Laboratory of Advanced Electromagnetic Engineering and Technology College of Electrical and Electronic EngineeringHuazhong University of Science and Technology

Focusing on the needs of radiated power measurement in J-TEXT tokamak,we designed a current preamplifier with stable performance for the weak signal from the AXUV detector. The amplifier circuit adopts a composite structure so as to suppress the high frequency noise.A photoelectric detection test system composed of a laser light source and an optical chopper is *** bandwidth and the stability of the equipment set including the current preamplifier and AXUV detector are tested by the test system *** the test on the preamplifier individually by a current source,it is found that an oscillating signal can easily arise in the test with AXUV *** phenomenon comes from the parasitic capacitance of the detector by a detailed analysis from the circuit's transfer *** a systematic test and analysis,we developed an amplifier with the gain of 5.1×10～5V/A,the bandwidth of 10 *** the same time,the amplifier can ensure the system stability and signal undistorted ***,due to the terrible electromagnetic environment in the J-TEXT tokamak,the methods of grounding, shielding and wire layout were analyzed and *** noise level is decreased to less than 20mV while *** experimental tests in J-TEXT tokamak indicate that the amplifier can provide a precise result about the sawtooth and precursor oscillation phenomena on the radiation signal.

关键词： Development of the current preamplifier for the radiation diagnostic on J-TEXT

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Large scale N2 plasma induced by electron beam at high pressure

Large scale N2 plasma induced by electron beam at high press...

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IEEE International Conference on Plasma Science (ICOPS)

作者： X. Pei K. Chen X. Lu State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan Hubei China

Summary form only given. Plasma induced by electron beam (EB) have been receiving widely attentions for its attractive features compared with traditional plasma generation techniques such as dielectric barrier discharge, electron cyclotron resonance and the surface wave 1 . This plasma source has higher ionization and dissociation efficiencies and can generate large scale non-equilibrium plasma at high pressure. Besides, by using high energy electron beam, it is convenient to control the electron density via modulation of beam parameters such as the beam energy. In this paper, a large scale non-equilibrium plasma, Fig. 1 which has a diameter of 50 cm and length of 35 cm at 20 kPa N 2 induced by electron beam is reported. The experimental results are consistent with the results simulated by software EGSnrc. The emission spectra reveals that the plasma contains abundant excited N* 2 and N + 2 . It is similar to the traditional plasma generation techniques such as pulse discharge. The rotational and vibrational temperature of the plasma next to the electron beam entrance is about 550 and 1700 K, respectively. The results of time evolution experiment show that there are no obvious influences of space charge on this plasma.

关键词： Plasmas Electron beams Discharges (electric) laboratories electromagnetics electromagnetic scattering

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Recent progress on the dynamics of atmospheric pressure plasma jet

Recent progress on the dynamics of atmospheric pressure plas...

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IEEE International Conference on Plasma Science (ICOPS)

作者： XinPei Lu State key laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan Hubei China

Summary form only given. Due to several urgent applications, room temperature atmospheric pressure plasma jets (RT-APPJs) have attracted lots of interest worldwide in the past decade and many different types of RT-APPJs have been reported. One of the most interesting phenomena of RT-APPJs, i.e. “plasma bullet” behavior has been studied by many different groups. We know much more about the “plasma bullet” now than in the beginning. In this paper, an overview of the research on the “plasma bullet” behavior will be presented, which including the effect of the photoionization, seed electrons, Penning ionization, gas flow rate, polarity of the applied voltage, pulse rising time, pulse repetition frequency, and pulse width. In addition, some newly discovered “plasma bullet” phenomena, including the multiple bullets for a single voltage pulse, dragon shape propagation path, and virtual electrode propagation of the plasma plume are reported 1-5 .

关键词： Ionization laboratories electromagnetics Educational institutions Plasma temperature Fluid flow

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HIGH-VOLTAGE POWER SUPPLY FOR ECRH SYSTEM ON J-TEXT TOKAMAK

HIGH-VOLTAGE POWER SUPPLY FOR ECRH SYSTEM ON J-TEXT TOKAMAK

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IEEE Symposium on Fusion engineering

作者： S. X. Ma M. Zhang L. L. Xia K. X. Yu State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan China 430074

ISBN: (纸本)9781479901708

A 100kV/60A high-voltage power supply (HVPS) has been established to energize the electron cyclotron resonance heating (ECRH) system for J-TEXT tokamak. With the pulse step modulation (PSM) technology, the HVPS has many advantages, especially the low stored energy and short protective time in case of short-circuit fault. This paper gives a description and key design features for the isolated transformers, switch power supplies (SPS) modules, measurement equipments and controller. In this HVPS, 4 dry-type transformers with 36 secondary-windings drive the 144 series SPS modules and isolate the high voltage between the rectifiers and the 6.3kV AC bus. A controller based on the PXI technology, which conforms to the ITER CODAC standard, has been developed to operate the series switches in each SPS module. The error signals from all the modules are monitored by the controller and the fast protection responses any over current fault in less than 5 μs. Moreover, to acquire better dynamic response and stability, a control strategy improved from the conventional PWM phase-shift modulation method has been proposed. The experimental results are also presented and show that the power supply system performing good.

关键词： HVPS PSM SPS modules PXI technology control

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Measurement of reactive species density in the battery-operated, handheld room temperature atmospheric plasma jet for biomedical applications

Measurement of reactive species density in the battery-opera...

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IEEE International Conference on Plasma Science (ICOPS)

作者： X. Pei J. Liu X. Lu State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan Hubei China

Room temperature atmospheric pressure plasma jets (RTAPP-Js) have widespread biomedical and health care applications in pathogen inactivation, wound healing, blood coagulation, and interventional oncology, to mention just a few. The overwhelming majority of the existing RTAPP-Js rely on external power (e.g., generators or wall power) and gas feed (e.g., He or Ar gas) supply. This limits their utility in mobile handheld devices for point-of-care applications, e.g., in natural disaster rescue and military combat operations, treatments in remote locations, etc. Moreover, treatment efficacy of such devices should be comparable or superior to current equipment. Recently, Pei et al. have developed a handheld RTAPP-Js (named “Plasma Flashlight”) powered by a 12 V DC battery 1 . The plasma source does not rely on any external power or feedstock gas supplies. In this report, we quantitative measured the O 3 density of the Plasma Flashlight by absorption spectroscopy which was performed with a standard mercury lamp. Atom O and OH radicals that play a crucial role in the inactivation process were measured using the laser-induced fluorescence (LIF) technology. The distribution of Atom O and OH radicals in the plasma plum was also studied.

关键词： Atmospheric measurements Biomedical measurement Temperature measurement Atomic measurements Density measurement Plasma temperature

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Study on fault current of DFIG during slight fault condition

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Telkomnika - Indonesian Journal of Electrical engineering 2013年第4期11卷 2221-2230页

作者： Kong, Xiangping Zhang, Zhe Yin, Xianggen Li, Zhenxing The State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan 430074 China

In order to ensure the safety of DFIG when severe fault happens, crowbar protection is adopted. But during slight fault condition, the crowbar protection will not trip, and the DFIG is still excited by AC-DCAC converter. In this condition, operation characteristics of the converter have large influence on the fault current characteristics of DFIG. By theoretical analysis and digital simulation, the fault current characteristics of DFIG during slight voltage dips are studied. And the influence of controller parameters of converter on the fault current characteristics is analyzed emphatically. It builds a basis for the construction of relay protection which is suitable for the power gird with accession of DFIG. © 2013 Universitas Ahmad Dahlan.

关键词： Electric fault currents

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Field studies for transient stability in continuous operation and contingency condition during 3 − Φ short circuit at PCC for grid connected 10MW Kastina wind farm

Field studies for transient stability in continuous operatio...

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IEEE PES Asia-Pacific Power and Energy engineering Conference (APPEEC)

作者： Owolabi Sunday Adio Xiangning Lin Jinwen Sun Feng Zhao Dexian Yang State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology(HUST) Wuhan China

As a result of world's energy resources crisis and environment pollution increasingly aggravating, distributed generation (DG) based on renewable energy has become a developmental trend for electric power industry in 21 century. However, DG's are usually affected by natural conditions being not able to output power continuously and steadily, so when large scale wind turbine generators are incorporated into the grid there is likely attendance impact it would bring on electric power system stability. In this investigation, the wind farm connection was done at 33/1 1kV level at Kastina substation located at Northern part of Nigeria. This paper is to establish voltage instability and frequency fluctuation that might be associated with the connection of the wind farm to the existing grid. The DigSILENT Power Factory software was used for modeling and simulation analysis of the studies and the results shows that when wind farm is connected to the grid, large clearance time is required for the fault to be cleared for voltage and frequency to become normalize again as compare with normal grid system. The studies has verified transient stability associated problem due to voltage and frequency stability variation phenomenon during the disconection of both windfarm and the load from the existing grid and is easier to predict in future the setting of protective devices and clearance time.

关键词： Power system stability Wind farms Stability analysis Transient analysis Circuit stability Rotors

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Modeling technology in traveling-wave fault location

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Telkomnika - Indonesian Journal of Electrical engineering 2013年第6期11卷 3333-3340页

作者： Jinrui, Tang Xianggen, Yin Zhe, Zhang State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan 430074 China

Theoretical research and equipment development of traveling-wave fault location seriously depend on digital simulation. Meanwhile, the fault-generated transient traveling wave must be transferred through transmission line, mutual inductor and secondary circuit before it is used. So this paper would maily analyze and summarize themodeling technology of transmission line and mutual inductor on the basis of the research achievement. Firstly several models of transmission line (multiple or T line model, Bergeron line model and frequency-dependent line model) are compared in this paper with analysis of wave-front characteristics and characteristic frequency of traveling wave. Then modeling methods of current transformer, potential transformer, capacitive voltage transformer, special traveling-wave sensor and secondary cable are given. Finally, based on the difficult and latest research achievements, the future trend of modeling technology in traveling-wave fault location is prospected. © 2013 Universitas Ahmad Dahlan.

关键词： Transmission line theory

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Joint filtering scheme of multistation GSM interference for UHF-band radar

Joint filtering scheme of multistation GSM interference for ...

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2013 IEEE International Conference on Signal Processing, Communications and Computing, ICSPCC 2013

作者： Shi, Longfei Ren, Bo Li, Yongzhen Zhao, Feng Xiao, Shunping State Key Lab. of Complex Electromagnetic Environment Effects on Electronics and Information System Changsha 410073 China School of Electronic Science and Engineering National University of Defense Technology Changsha 410073 China

ISBN: (纸本)9781479910274

UHF-band radar, which is widely used in early warning, has the unique advantage on target detection. However it can be seriously interfered by the GSM base station with the same frequency channel in practical application. Nowadays the solution is just avoiding the frequency which GSM used. However, with the increasing number of GSM clients, the spectrum which can be used by UHF-radar will be compressed inevitable. It not only leads to the frequency resource wasted, but also impacts the detection ability of UHF-band radar. A polarization-space joint filtering scheme is proposed in this paper, which is based on the antenna configuration with orthogonal dual-polarization array elements and main, auxiliary arrays. By employing this filtering scheme, the radar can detect targets effectively, even there is much interference in the main lobe and side lobe simultaneously. The detection ability of UHFband radar will be effectively improved in complex electromagnetic environment by using this method. In this paper, the model of signal received by array is established, and the recursive filtering algorithm is designed. The simulation is finally done to validate. © 2013 IEEE.

关键词： Antennas

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