- 标题
- 摘要
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- 实验方案
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[IEEE 2018 International Symposium on Electromagnetic Compatibility (EMC EUROPE) - Amsterdam (2018.8.27-2018.8.30)] 2018 International Symposium on Electromagnetic Compatibility (EMC EUROPE) - Emission Measurement of a Solar Park in the Frequency Range of 2 to 150 kHz
摘要： Although a few years have passed since the first electromagnetic compatibility problems occurred in the frequency range of 2 to 150 kHz, but we still lack fundamental standards, especially related to emission, that would ensure electromagnetic compatibility. Our aim was to get a better picture about the emission of a solar inverter and also about how disturbances generated by more inverters spread and aggregate on the grid. Thus, based on on-site measurements, this paper investigates the non-intentional supraharmonic emission (both current and voltage) of a solar park that consists of a total of 50 individual PV (photovoltaic) modules and inverters. Supraharmonic voltages and currents were measured at three locations: at one individual PV unit, at a busbar collecting the production of ten PV units and at the transformer, which connects the park with the grid. It was shown that the aggregation of these disturbances is a very complex process, but supraharmonic currents are more likely to flow between the inverters than into the grid. Another important result is that an alteration in production does not significantly change emission levels.
关键词： 2 kHz – 150 kHz,electromagnetic compatibility,supraharmonic emission,inverter,solar park
更新于2025-09-23 15:23:52
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[IEEE 2018 International Symposium on Electromagnetic Compatibility (EMC EUROPE) - Amsterdam (2018.8.27-2018.8.30)] 2018 International Symposium on Electromagnetic Compatibility (EMC EUROPE) - High-Resolution Near-Field Imaging and Far-Field Antenna Measurements with Atomic Sensors
摘要： Measurements of radio-frequency (RF) electric fields using atomic sensors based on quantum-optical spectroscopy of Rydberg states in vapors has garnered significant interest in recent years for the establishment of atomic standards for RF electric fields and towards the development of novel RF sensing instrumentation. Here we describe recent work employing atomic sensors for sub-wavelength near-field imaging of a Ku-band horn antenna. We demonstrate near-field imaging capability at a spatial resolution of λ/10 and measurements over a 72 to 240 V/m field range using off-resonance AC-Stark shifts of a Rydberg-atom resonance. A fiber-coupled atomic-sensor probe is also employed in far-field measurements of a WR-90 standard gain horn.
关键词： electromagnetic compatibility,Rydberg,atom,quantum sensing,RF,metrology,antenna characterization,microwave,Atomic sensors,electric field,antenna,radio-frequency
更新于2025-09-23 15:23:52
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[IEEE 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Odessa, Ukraine (2018.9.4-2018.9.7)] 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - The Wideband Pulsed Antenna and its Application
摘要： This paper presents a design of the antenna with an expandable slot for effective radiating and receiving the ultra-wideband (UWB), short-pulse (SP) signals. The offered design of the antenna allows creating an interferential electromagnetic field of a bipolar pulse in an equivalent general antenna aperture. A quantitative and quality is evaluation of efficiency of proposed antenna design performed. It is shown that an application of the given antenna allows increasing the damaging range from acting the pulsed UWB signals.
关键词： temporal position-pulse transmission,wireless system,electromagnetic compatibility,wideband pulsed antenna,ultrawideband signal,data modulation
更新于2025-09-23 15:21:21
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Insight into the compatibility between C4F7N and silver: Experiment and theory
摘要： Fluorinated nitrile (C4F7N) has received much attention as substitute gas for sulfur hexafluoride (SF6) using in electrical equipment over the past two years. In this paper, we explored the compatibility between C4F7N and silver theoretically and experimentally. The interaction mechanism between C4F7N and silver was investigated based on the density functional theory (DFT) and the composition characteristics of C4F7N and silver after long term interaction were also revealed. It was found that the most energetically favorable adsorption structure has the adsorption energy of 0.69 eV with 0.024e charge transfer. Electron localization function (ELF) also shows evidently electron delocalization region between C4F7N and Ag (1 1 1). Thus the interaction mechanism belongs to physisorption and the van der Waals force plays a major role. The gas composition of C4F7N, the morphology and crystal structure of silver did not have any obvious change after 70 days’ interaction, which indicates the compatibility between C4F7N and silver is great.
关键词： fluorinated nitrile,compatibility,SF6 alternative gas,silver
更新于2025-09-23 15:21:01
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[IEEE 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Paris, France (2018.7.8-2018.7.13)] 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Evaluation of EMI Effects on Static Electricity Meters
摘要： Recent studies involving large errors in static electricity meters when exposed to step changes in the current waveform are reviewed. Triggered by these findings, a joint European research project has recently started to further evaluate these effects. A description is given of this pre-normative research programme which aims to provide evidence and techniques to resolve this unsatisfactory meter error situation. The need or otherwise for a regulatory and standardisation response to these large meter errors is discussed.
关键词： watthour meters,standards,energy measurement,EMC immunity testing,static meters,Electromagnetic Compatibility
更新于2025-09-23 15:21:01
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ultra-fine tuning
摘要： Researchers from Xi’an University of Technology in China, alongside researchers from the ENSEIRB and the IERF in France, propose an auto-tuning network for a phased-array high intensity focused ultrasound (HIFU) system based on a variable synchronous switched capacitor. The novel system is capable of automatically compensating for the reactive power and impedance drifts, caused by temperature fluctuations and manufacturing errors, in circuit transducers and complies with magnetic resonance imaging (MRI) compatibility regulations.
关键词： phased-array,variable synchronous switched capacitor,high-intensity focused ultrasound,HIFU,Auto-tuning network,MRI compatibility
更新于2025-09-23 15:21:01
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[IEEE 2019 Compound Semiconductor Week (CSW) - Nara, Japan (2019.5.19-2019.5.23)] 2019 Compound Semiconductor Week (CSW) - Effect of introducing optical blanking to GaN epitaxy by using pulsed laser deposition technology
摘要： Our reports of published research in several of the peer-reviewed journal articles in 1996, 2002, and 2004 have generated a lot of controversy over the last two decades, including the most recent publication by Foster and Chou. In this paper, we present arguments based on physics that the main reason for higher exposure of children (also women and men with smaller heads and likely thinner pinnae) to radiofrequency energy from mobile phones is the closer placement of the cell phone radiation source by several millimeters to the tissues of the head, e.g., the brain. Using heterogeneous anatomically derived shaped models of the head, we have previously reported that the exposure increases by a compounding rate of 10%–15% for every single millimeter of closer location of the radiating antenna. This is similar to the report of ～20% increase for every millimeter in the Foster and Chou’s paper from their (1) even though their simplistic (1) is valid only for a homogenous tissue slab of in?nite size and the radiation source that is a wire dipole rather than a mobile telephone. Both of their assumptions for (1) are obviously not applicable for human exposures to mobile telephones. Actually, the physical reason for such a rapid drop off of coupled energy is that the radiofrequency electromagnetic ?elds close to a radiating source in the so-called near-?eld region reduce in strength very rapidly with every millimeter of distance, even faster than in the far-?eld region, where the electromagnetic ?elds reduce inversely with the square of the distance from the source.
关键词： antennas and radiation,EM compatibility,Mobile telephones,exposure of children
更新于2025-09-23 15:19:57
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - New Phase Modulator with Large Stroke and High Bandwidth for Improved Coherent Coupling Schemes
摘要： High-frequency signals on interconnects can cause significant radiated electromagnetic emissions. An intermediate level modeling method aimed at providing a faster solution with less computing resources to allow designers to obtain rapid approximations is desirable. This paper presents a modeling technique to speed up the evaluation of radiated fields from interconnect cables. Based on the Hertzian dipole radiation theory and transmission-line frequency-dependant solutions, the radiating source is modeled by the sum of a large number of short dipoles. This model allows the contributions of line-end discontinuities to be included through a vector network analyzer measurement together with a monopole approximation. The proposed method is verified by open-line and RG 58 coaxial cable measurements.
关键词： radiated electromagnetic emissions,Dipole radiation,transmission-line (TL) modeling,electromagnetic compatibility
更新于2025-09-19 17:13:59
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[IEEE 2019 6th International Conference on Image and Signal Processing and their Applications (ISPA) - Mostaganem, Algeria (2019.11.24-2019.11.25)] 2019 6th International Conference on Image and Signal Processing and their Applications (ISPA) - Enhanced Performance of Substrate Integrated Waveguide Bandstop Filter Based on Metamaterials SCSRRs
摘要： High-frequency signals on interconnects can cause significant radiated electromagnetic emissions. An intermediate level modeling method aimed at providing a faster solution with less computing resources to allow designers to obtain rapid approximations is desirable. This paper presents a modeling technique to speed up the evaluation of radiated fields from interconnect cables. Based on the Hertzian dipole radiation theory and transmission-line frequency-dependant solutions, the radiating source is modeled by the sum of a large number of short dipoles. This model allows the contributions of line-end discontinuities to be included through a vector network analyzer measurement together with a monopole approximation. The proposed method is verified by open-line and RG 58 coaxial cable measurements.
关键词： radiated electromagnetic emissions,Dipole radiation,transmission-line (TL) modeling,electromagnetic compatibility
更新于2025-09-19 17:13:59
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Laser-assisted surface processing for functionalization of polymers on micro- and nano-scale
摘要： Rapid manufacturing of functionalized polymers enable a cost-ef?cient method for many applications in the biological, and medical sector. Laser structuring techniques differ for fast fabrication processes of thermoplastics. Here we report on direct UV laser ablation of polystyrene and polydimethylsiloxane to control wettability and bio-compatibility. For this purpose contact angle measurements and L929 cell growth experiments were performed as function of laser and process parameters. This work also describes the potential of laser-assisted hot embossing which has been introduced to replicate pre-fabricated micro- and nano-sized structures onto polymers proving it to be a cost-ef?cient and ?exible method for surface functionalization. Therefore, pre-fabricated laser-induced periodic surface structures have been manufactured as mould inserts using ultrafast laser radiation near the ablation threshold. These mould inserts can also be made of nickel, silicon or glass proving laser-assisted hot embossing to be a versatile tool for the functionalization of thermoplastics and meet the requirements for modern manufacturing with regard to quality and production ?exibility.
关键词： Bio-compatibility,Functionalization of polymers,Wettability,Laser-assisted surface processing,Laser-assisted hot embossing,Micro- and nano-scale
更新于2025-09-19 17:13:59