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Conference on Electrical Insulation and Dielectric Phenomena, (CEIDP)

作者： Hua Li Zhiwei Li Fuchang Lin Yaohong Chen De Liu Bowen Wang Haoyuan Li Qin Zhang State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology HUST Wuhan P. R. China

Metalized polypropylene film capacitors (MPPFCs) can work under high electric fields due to the self-healing characteristic. Leakage phenomenon caused by the insulation resistance (IR) in MPPFCs is one of the important factors resulting in the reduction of the energy efficiency. The IR is directly related to the DC electric conduction mechanism in polypropylene film. This paper mainly concentrates on the IR by investigating the electrical conduction mechanism of metalized films under high electric fields. Firstly the conduction mechanism of metallized films is discussed. Secondly IR is obtained under different electric fields based on an established measurement platform The Poole-Frenkel(PF) model presented in this paper includes the field-enhanced carrier density caused by the barrier height attenuation in directions both opposite and forward to the electric field, and the field-enhanced carrier mobility. The equation for electric conductivity based on this model gives not only the usual Ohm's law at low fields but also at extremely high electric fields. And the IR calculations match well with the experimental results.

关键词： Electric fields Conductivity Films Capacitors Resistance Current measurement

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Studying on dimensional standardization of UHF partial discharge detection system

Studying on dimensional standardization of UHF partial disch...

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2013 IEEE Conference on Electrical Insulation and Dielectric Phenomena, CEIDP 2013

作者： Hong, L. Qizheng, Ye Xingwang, Li Qifu, Lu Zhiguo, Tang Tian, Chen Electric Power Research Institute of Guangdong Power Grid Corporation Guangdong 510080 China State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan 430074 Hubei Province China State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University Beijing 102206 China

ISBN: (纸本)9781479925964

In the ultra-high-frequency (UHF) partial discharge (PD) detection system, many physical quantities, such as voltage, charge, power and their normalization, were used to describe the UHF PD signal. The standardization of the dimensional has not been investigated thoroughly. Based on the PD forming mechanisms, the pulse transient electric field was presented as a main physical quantity in this paper. The minimum pulse transient electric field, which could be differentiated by the UHF PD detection system, was adopted as the sensitivity of detection system. The sensitivities of four detection systems were measured by GTEM platform, and comparison tests for Spike discharge in GIS were made. The experimental results were in accordance with the sensitivity of detection system. © 2013 IEEE.

关键词： Standardization

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The Experimental Research on a Small Size Magnetic Coupling Resonance Wireless Energy Transmission System

The Experimental Research on a Small Size Magnetic Coupling ...

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第十五届中国科协年会

作者： YANG Xinsheng ZHAO Jun XU Guizhi LI Xuan LI Wei LI Yang Province-Ministry Joint Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability Tianjin Key Laboratory of Advanced Electrical Engineering and Energy Technology Tianjin Polytechnic

With the progress of technology,more and more small household electrical appliances,implanted devices and other electronic equipment have been widely *** energy supply problem has restricted the development of electronic equipment,especially for implanted *** coupling resonance wireless energy transmission system is a new wireless energy transmission mode and it can realize the middle distance power transmission so it can solve the problems *** this paper,Ansoft software was used to simulate the electric field distribution of the magnetic coupling resonance *** the same time experiments were carried out to make the system into air,simulating human tissue fluid and a piece of pork respectively to compute the transmission *** result shows that the system can satisfy the power requirement of implanted device and so on,so it has broad application prospect.

关键词： wireless energy transfer vivo implanted device magnetic coupling resonance small-sized resonator transmission efficiency

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Room temperature direct current air plasma jet for biomedical applications

Room temperature direct current air plasma jet for biomedica...

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IEEE International Conference on Plasma Science (ICOPS)

作者： S. Wu Z. Wang Q. Huang X. Lu K. Ostrikov State key laboratory of advanced electromagnetic engineering and technology Huazhong University of Science and Technology Wuhan Hubei China Huazhong University of Science and Technology Wuhan Hubei CN

Summary form only given. Atmospheric-pressure room-temperature plasma jets are commonly used in plasma medicine, nanotechnology, as well as surface and materials processing. Most of the applications require room-temperature operation while completely avoiding the glow-to-arc transitions. To meet these requirements, the atmospheric plasma jets are usually sustained in noble gases. However, this is very challenging for the open-air operation. Moreover, the cross-sections of the plasma plumes are typically very small, which make large-area surface processing particularly difficult. One promising way to overcome this shortcoming is by using the plasma jet arrays. However, since the individual plasma plumes generated by the arrayed plasma jets are in most cases independent and do not merge in open air, it is very difficult to achieve uniform plasmas and surface treatment effects. In this paper, we demonstrate a homogenous cold air plasma glow with a large cross-section generated by a direct current power supply. There is no risk of glow-to-arc transitions, and the plasma glow appears uniform regardless of the gap between the nozzle and the surface being processed. Detailed studies show that both the position of the quartz tube and the gas flow rate affect the plasma characteristics. Further investigation indicates that the residual charges trapped on the inner surface of the quartz tube may be responsible for the generation of the air plasma plume with a large cross-section. Moreover, the spatially resolved optical emission spectroscopy reveals that the air plasma plume is uniform as it propagates out of the nozzle. The air plasma plume with remarkable improvement of the plasma uniformity is used to improve the bio-compatibility of a glass coverslip over a reasonably large area. This improvement is demonstrated by a much more uniform and effective attachment and proliferation of human embryonic kidney 293 (HEK 293) cells on the plasma-treated surface.

关键词： Surface treatment Educational institutions Australia Electron tubes Plasma temperature Laboratories

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Short circuit analysis for integration of 10MW Windfarm in Nigeria at the PCC

Short circuit analysis for integration of 10MW Windfarm in N...

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IEEE General Meeting Power& Energy Society

作者： Owolabi Sunday Adio Xiangning Lin Feng Zhao Zhiqian Bo State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan China Smart Grid Institute State Grid Beijing CHINA

A short circuit in a power system can cause very high currents to flow to the fault location. The magnitude of the short circuit current depends on the impedance of system under short circuit conditions. However, to study the effect of windfarm integrated into Power Holding Company of Nigeria (PHCN) which is power bureau of the country, a short circuit calculation was performed studies conducted. The analysis was carried out in two stages, one was using Thevenin equivalent to roughly check unbalance short current from PHCN external source from Kaduna substation at 132/33kV, although this was actually not part of the current studies. The second part was to performed short circuit analysis at network where the windfarm will be connected through 33/11kV level (PCC), which is for this current studies by using computer software tool (DigSILENT powerfactory). This was done to verify the withstands of capacity for the main substation equipment and the new OHLs in comparison with the 3-phase and 1-phase to ground short circuit calculated values of grid studies for the windfarm project. In the network calculation, consideration was made for both maximum and minimum short circuit conditions and it is performed according the IEC 60909 (2001) standards. However, the aim of the analysis was the assessment of the electrical parameters of the WindFarm during and after a three phase short circuit event at the 33 kV Kastina substation because this is the point where the windfarm have to be connected and also the location of the wind generators.

关键词： Software Substations Gold

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Analysis of d- and q-axis inductances and saliency ratios in interior permanent magnet machines with fractional-slot concentrated- windings considering harmonic effects

Analysis of d- and q-axis inductances and saliency ratios in...

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International Conference on Electrical Machines and Systems (ICEMS)

作者： Xiaolong Zhang Ronghai Qu Hong Chen Jian Luo State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan China UCAS EV Co. Ltd Shanghai China

The interior permanent magnet (IPM) machine with fractional-slot concentrated-windings (FSCW) has become a popular research topic owing to their novel structures and attracting potentials. This paper is focused on inductances and saliency ratios in IPM FSCW machines with different pole and slot combinations. Analytical expressions of inductances and saliency ratios are derived using harmonic analysis method (HAM) and their features and trends are concluded. The concept of dq-axis equivalent windings containing harmonic components is proposed to help better understand these features and trends. It explains the phenomenon that configurations with fewer stator slots and fewer winding layers have lower saliency ratio. Theoretical conclusions are verified by finite-element (FE) method.

关键词： Windings Harmonic analysis Inductance Power capacitors Rotors Atmospheric modeling Stator windings

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High Power Factor Vernier Permanent Magnet Machines

High Power Factor Vernier Permanent Magnet Machines

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IEEE Energy Conversion Congress and Exposition

作者： Dawei Li Ronghai Qu Thomas Lipo State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical & Electronic Engineering Huazhong University of Science and Technology Wuhan China Department of Electrical and Computer Engineering University of Wisconsin Madison Madison USA

ISBN: (纸本)9781479903375

Vernier permanent magnet (VPM) machines are well known for high torque density but low power factor. This paper deals with the low power factor of VPM machines. The goal is not obtained by reducing the electrical loading or adjusting current advance angle but proposing a novel vernier topology- dual-stator, spoke-array (DSSA) VPM topology. In this paper, the characteristics, such as active part, auxiliary mechanical structure and rotor anisotropy, of the DSSA VPM topology are analyzed in detail. Performances, including power factor, torque density, and cogging torque etc., are evaluated based on finite element analysis (FEA). The analysis results show that the DSSA VPM topology exhibits high power factor viz.,～0.9 and significantly high torque capability. Finally, the prototype machine has been designed, built, and is under testing. The verification of the mechanical structure scheme is done in this paper, and the experimental results will be presented in the near future.

关键词： High power factor dual-stator spoke-array vernier permanent magnet machine Reactive power Domain-Specific Software Architecture high torque Permanent magnet synchronous machines cogging torque MECHANICAL STRUCTURES machine topology

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Research on electromagnetic environment to chest via witricity

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Diangong Jishu Xuebao/Transactions of China Electrotechnical Society 2013年第SUPPL.2期28卷 200-203页

作者： Zhao, Jun Yang, Xinsheng Xu, Guizhi Li, Yang Province-Ministry Joint Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability Hebei University of Technology Tianjin 300130 China Tianjin Key Laboratory of Advanced Electrical Engineering and Energy Technology Tianjin Polytechnic University Tianjin 300387 China

Magnetic coupling resonance wireless energy transmission(Wireless electricity, Witricity) is a new technology put forward by MIT in 2007. Witricity achieves middle distance wireless energy transmission through magnetic coupling resonance and it has good application prospect in the field of implantable devices. The specific absorption rate (SAR) is applied to express the magnitude of electromagnetic energy which is absorbed by local tissue of human body. In this paper a small size resonator was designed and the experiment results show that the small size Witricity system can transmit energy well. The SAR is calculated by finite difference time domain (FDTD) method through building 3D numerical model of chest and implantable coil. Results show that when transporting energy to chest implantable devices via Witricity, the maximum SAR value for 1g and 10g organism are 0.454 3W/kg and 1.072 9W/kg respectively which are both below international limit value.

关键词： Finite difference time domain method

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Numerical modeling the interaction between externally applied resonant magnetic perturbations and tearing instabilities

Numerical modeling the interaction between externally applie...

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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： Qiming Hu Q.Yu Bo Rao Ge Zhuang Yonghua Ding Wei Jin Nengchao wang Xiwei Hu State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Max-Planck-Institut für Plasmaphysik EURATOM association85748 GarchingGermany

To compare with resonant magnetic perturbations(RMPs) related experimental results observed in J-TEXT tokamak,nonlinear numerical modeling based on reduced MHD equations has been carried *** experimental parameters as input,both the mode locking and mode stabilization by RMPs are also obtained from numerical modeling. Further calculations have been carried out to study the plasma parameters affecting the mode stabilization by RMPs,including the plasma rotation frequency,viscosity,Alfven velocity and the RMP *** is found that the suppression of the tearing mode by RMPs of moderate amplitude is possible for a sufficiently high ratio of plasma rotation velocity to the Alfven speed.A larger plasma viscosity enhances the mode stabilization. In addition,the non-uniform mode rotation frequency,modulated by electromagnetic force(Fern) and viscous force(Fvs),results in the applied RMPs contributing both net stabilizing and braking effect on *** evaluation based on analytical theory shows the applied RMP contributes a dominant stabilizing effect,which are responsible for the suppression of *** dynamics of the first discovered small locked island(SLI) are *** is found that the island is locked at the stabilizing phase and the saturated island width is less than the linear layer *** simulated Mirnov signal indicates the small locked island is likely to be the complete suppression case observed in experiments. The comparisons between the numerical and experimental results are in good agreement.

关键词： Numerical modeling the interaction between externally applied resonant magnetic perturbations and tearing instabilities

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Cooperation mechanism of wide-area protection system based on multi-agents

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Telkomnika - Indonesian Journal of Electrical engineering 2013年第1期11卷 195-202页

作者： Zhang, Mingzhu Li, Zhenxing School of Mathematics and Statistics Xuchang University Henan Province China The State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan 430074 China

With the rapid growth of power system, it is becoming increasingly difficult to realize reach and time coordination for conventional backup protection. To cope with those problems, wide-area protection is widely researched. In this paper, a novel dynamic cooperation mechanism of wide-areaprotection is proposed, which can operate better than distributed and centralized systems with respect to reliability, section selectivity, and so on. The multi-agents technology is used to enhance adaptability and decrease communication traffic of wide-area protection system. The improvement of backup protection performance to overcome some specific conditions, such as communication bit error, protection failure, and breaker failure, is also illustrated by utilizing communication networks and distributed protection agents which enables an easy and flexible construction and operation of the proposed wide-area protection system. The example analysis on IEEE 5 nodes system shows the concrete cooperation processing among agents in the cases of typical faults. © 2013 Universitas Ahmad Dahlan.

关键词： Multi agent systems

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