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arXiv 2021年

作者： Yang, Ki Youl White, Alexander D. Ashtiani, Farshid Shirpurkar, Chinmay Pericherla, Srinivas V. Chang, Lin Song, Hao Zou, Kaiheng Zhou, Huibin Pang, Kai Yang, Joshua Guidry, Melissa A. Lukin, Daniil M. Hao, Han Trask, Lawrence Ahn, Geun Ho Netherton, Aandy Briles, Travis C. Stone, Jordan R. Rechtman, Lior Stone, Jeffery S. van Gasse, Kasper Skarda, Jinhie L. Su, Logan Vercruysse, Dries MacLean, Jean-Philippe W. Aghaeimeibodi, Shahriar Li, Ming-Jun Miller, David A.B. Marom, Dan Papp, Scott B. Willner, Alan E. Bowers, John E. Delfyett, Peter J. Aflatouni, Firooz Vučković, Jelena E.L.Ginzton Laboratory Stanford University StanfordCA United States Department of Electrical and Systems Engineering University of Pennsylvania PhiladelphiaPA United States The College of Optics and Photonics University of Central Florida OrlandoFL32816 United States Department of Electrical and Computer Engineering University of California Santa BarbaraCA United States Department of Electrical Engineering University of Southern California Los AngelesCA United States Time and Frequency Division National Institute of Standards and Technology BoulderCO United States Applied Physics Department The Hebrew University of Jerusalem Jerusalem Israel Corning Incorporated CorningNY United States Department of Physics University of Colorado BoulderCO United States

Modern microelectronic processors have migrated towards parallel computing architectures with many-core processors. However, such expansion comes with diminishing returns exacted by the high cost of data movement between individual processors. The use of optical interconnects1,2 has burgeoned as a promising technology that can address the limits of this data transfer. While recent pushes to enhance optical communication have focused on developing wavelength-division multiplexing technology, this approach will eventually saturate the usable bandwidth, and new dimensions of data transfer will be paramount to fulfill the ever-growing need for speed3–6. Here we demonstrate an integrated intra- and inter-chip multi-dimensional communication scheme enabled by photonic inverse design. Using inverse-designed mode-division multiplexers, we combine wavelength- and mode- multiplexing and send massively parallel data through nano-photonic waveguides and optical fibres. Crucially, as we take advantage of an orthogonal optical basis, our approach is inherently scalable to a multiplicative enhancement over the current state of the art. © 2021, CC BY.

关键词： parallel architectures

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Enhanced MPC for Fast Frequency Control in Inverter-Dominated Power systems

Enhanced MPC for Fast Frequency Control in Inverter-Dominate...

引用

International Conference on Smart Energy systems and Technologies (SEST)

作者： Ognjen Stanojev Uros Markovic Evangelos Vrettos Petros Aristidou Duncan Callaway Gabriela Hug EEH - Power Systems Laboratory ETH Zurich Zurich Switzerland Swissgrid AG Laufenburg Switzerland Department of Electrical Engineering Computer Engineering and Informatics Cyprus University of Technology Limassol Cyprus Energy & Resources Group UC Berkeley Berkeley CA US

ISBN: (数字)9781728147017

ISBN: (纸本)9781728147024

Due to the rising shares of renewable energy sources, future power systems are facing significant changes in control complexity and system inertia, thus making frequency regulation in power systems more challenging. This paper proposes a novel control scheme based on model predictive control for grid-forming Voltage Source Converters (VSCs), with the goal of exploiting their fast response capabilities and available DC-side energy storage to provide fast frequency control service to the system. An observer based on support vector machine regression detects and estimates system disturbances using only locally available measurements at each VSC. Frequency evolution is then anticipated through state-space predictions and the VSC power output is adjusted to compensate the disturbance and prevent frequency threshold violations. The proposed control scheme is evaluated and its effectiveness demonstrated through detailed time-domain simulations of the IEEE 39-bus test system.

关键词： Frequency control Power conversion Voltage control Frequency measurement Integrated circuit modeling Support vector machines

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Free-electron Brewster radiation

arXiv

引用

arXiv 2023年

作者： Chen, Ruoxi Chen, Jialin Gong, Zheng Zhang, Xinyan Zhu, Xingjian Yang, Yi Kaminer, Ido Chen, Hongsheng Zhang, Baile Lin, Xiao Interdisciplinary Center for Quantum Information State Key Laboratory of Extreme Photonics and Instrumentation ZJU-Hangzhou Global Scientific and Technological Innovation Center College of Information Science & Electronic Engineering Zhejiang University Hangzhou310027 China International Joint Innovation Center The Electromagnetics Academy Zhejiang University Zhejiang University Haining314400 China Department of Electrical and Computer Engineering Technion-Israel Institute of Technology Haifa32000 Israel School of Physics Zhejiang University Hangzhou310027 China Department of Physics University of Hong Kong 999077 Hong Kong Key Laboratory of Advanced Micro/Nano Electronic Devices & Smart Systems of Zhejiang Jinhua Institute of Zhejiang University Zhejiang University Jinhua321099 China Shaoxing Institute of Zhejiang University Zhejiang University Shaoxing312000 China Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University Singapore637371 Singapore Centre for Disruptive Photonic Technologies Nanyang Technological University Singapore637371 Singapore

Free-electron radiation offers an enticing route to create light emission at arbitrary spectral regime. However, this type of light emission is generally weak, which is intrinsically limited by the weak particle-matter interaction and unavoidably impedes the development of many promising applications, such as the miniaturization of free-electron radiation sources and high-energy particle detectors. Here we reveal a mechanism to enhance the particle-matter interaction by exploiting the pseudo-Brewster effect of gain materials – presenting an enhancement of at least four orders of magnitude for the light emission. This mechanism is enabled by the emergence of an unprecedented phase diagram that maps all phenomena of free-electron radiation into three distinct phases in a gain-thickness parameter space, namely the conventional, intermediate, and Brewster phases, when an electron penetrates a dielectric slab with a modest gain and a finite thickness. Essentially, our revealed mechanism corresponds to the free-electron radiation in the Brewster phase, which also uniquely features ultrahigh directionality, always at the Brewster angle, regardless of the electron velocity. Counterintuitively, we find that the intensity of this free-electron Brewster radiation is insensitive to the Fabry-Pérot resonance condition and thus the variation of slab thickness, and moreover, a weaker gain could lead to a stronger enhancement for the light emission. The scheme of free-electron Brewster radiation, especially along with its compatibility with low-energy electrons, may enable the development of high-directionality high-intensity light sources at any frequency. © 2023, CC BY.

关键词： Electrons

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NASDUCK SERF: New constraints on axion-like dark matter from a SERF comagnetometer

arXiv

引用

arXiv 2022年

作者： Bloch, Itay M. Shaham, Roy Hochberg, Yonit Kuflik, Eric Volansky, Tomer Katz, Or Berkeley Center for Theoretical Physics University of California BerkeleyCA94720 United States Theory Group Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Rafael Ltd. Haifa31021 Israel Department of Physics of Complex Systems Weizmann Institute of Science Rehovot76100 Israel Racah Institute of Physics Hebrew University of Jerusalem Jerusalem91904 Israel Department of Physics Tel Aviv University Tel Aviv Israel Duke Quantum Center Duke University DurhamNC27701 United States Department of Electrical and Computer Engineering Duke University DurhamNC27708 United States

Ultralight axion-like particles are well-motivated relics that might compose the cosmological dark matter and source anomalous time-dependent magnetic fields. We report on new terrestrial bounds on the coupling of axion-like particles to neutrons and protons. The detector uses nuclei of noble-gas and alkali-metal atoms and operates in the Spin-Exchange Relaxation-Free (SERF) regime, achieving high sensitivity to axion-like dark matter fields. Conducting a month-long search, we cover the mass range of 1.4 × 10−12 eV/c2 to 2 × 10−10 eV/c2 and provide world-leading limits which supersede robust astrophysical bounds, and improve upon previous terrestrial constraints by up to two orders of magnitudes for many masses within this range. These are the first reliable terrestrial bounds reported on the coupling of protons with axion-like dark matter, covering a new and unexplored terrain in its parameter space. © 2022, CC BY.

关键词： Dark Matter

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Demonstration of two-dimensional extreme skin depth engineering in CMOS photonics foundry

Demonstration of two-dimensional extreme skin depth engineer...

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2020 Frontiers in Optics Conference, FiO 2020

作者： van Niekerk, Matthew Jahani, Saman Bickford, Justin Cho, Pak Anderson, Stephen Leake, Gerald Coleman, Daniel Fanto, Michael L. Tison, Christopher C. Howland, Gregory A. Jacob, Zubin Preble, Stefan F. Microsystems Engineering Rochester Institute of Technology RochesterNY14623 United States Birck Nanotechnology Center Purdue University West LafayetteIN47907 United States Department of Electrical Engineering California Institute of Technology PasadenaCA91125 United States U.S Army Research Laboratory AdelphiMD20783 United States Electrical Computer and Systems Engineering Department Rensselaer Polytechnic Institute TroyNY12180 United States State University New York Polytechnic Institute AlbanyNY12203 United States Air Force Research Laboratory RomeNY13441 United States School of Physics and Astronomy Rochester Institute of Technology RochesterNY14623 United States

We implement extreme skin depth engineering (e-skid) in two dimensions to suppress or enhance evanescent coupling on-demand. This is demonstrated experimentally with a large gap, bendless directional coupler exhibitin... 详细信息

ISBN: (纸本)9781943580804

关键词： CMOS integrated circuits

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PVrosion: ACCELERATED CORROSION BLIND SPOTS INHERENT TO PHOTOVOLTAIC systems' OPERATION AND UNDETECTED DC FAULTS - TROJAN HORSE FOR DETERIORATING THE INTEGRITY OF CRITICAL INFRASTRUCTURES AND BUILDINGS

PVrosion: ACCELERATED CORROSION BLIND SPOTS INHERENT TO PHOT...

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The 12th Mediterranean Conference on Power Generation, Transmission, Distribution and Energy Conversion (MEDPOWER 2020)

作者： C. Melios A. Demetriou A. Christofe K. Neocleous T. Polydorou D. Hadjimitsis E. Christoforou S. Kallis M. Nicolaou L. Loizou G. Kyriacou Y. Papademetriou V. P. Androvitsaneas I. F. Gonos C. A. Charalambous Power Systems Modelling (PSM) Laboratory Department of Electrical and Computer Engineering University of Cyprus Nicosia Cyprus Department of Civil Engineering and Geomatics Faculty of Engineering and Technology Cyprus University of Technology Lemesos Cyprus Nortest Cyprus LTD Nicosia Cyprus Department of Electrical and Mechanical Services (EMS) Ministry of Transport Communications & Works Nicosia Cyprus Hellenic Copper Mines Ltd Nicosia Cyprus Union of Licensed Electricians Cyprus (SEHK) Nicosia Cyprus Cypenergia Nicosia Cyprus High Voltage Laboratory School of Electrical and Computer Engineering National Technical University of Athens Athens Greece

PVrosion: Accelerated Corrosion Blind Spots Inherent to Photovoltaic systems' Operation and Undetected DC Faults - Trojan horse for Deteriorating the Integrity of Critical Infrastructures and Buildings, is a 2019 project funded by the Research and Innovation Foundation of Cyprus. The project elaborates on a new issue that progressively receives attention by the photovoltaic (PV) installation industry and critical infrastructure's operators. It specifically introduces “DC stray current corrosion blind spots” that are inherent to PV systems' earthing and associated DC ground fault detection mechanisms. Blind spots arise as the existing protection thresholds for DC leakage currents have been based on other issues, such as fire or personnel safety. Using soil and concrete as conductive mediums, DC leakage currents can stray out of the area of PV installations and interfere with nearby third-party critical infrastructure. This article presents an overview of the project activities, attainments and intended outcomes.

关键词： leakage currents fault diagnosis corrosion photovoltaic power systems earthing power generation protection electrical installation power generation faults life testing

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Determining the Reaction Time for Triggering Supportive Control Actions to Guarantee Adequate Frequency Response in Smart Grids

Determining the Reaction Time for Triggering Supportive Cont...

引用

Spring Simulation Conference (SpringSim)

作者： Jiecai Luo Seddik M. Djouadi Mohammed M. Olama Yichen Zhang Electrical Engineering Department Southern University and A&M College Baton Rouge LA USA Min H. Kao Department of Electrical Engineering & Computer Science University of Tennessee Knoxville TN USA Computational Sciences & Engineering Division Oak Ridge National Laboratory Oak Ridge TN USA Energy Systems Division Argonne National Laboratory Lemont IL USA

ISBN: (数字)9781565553705

ISBN: (纸本)9781728163642

The progressive integration of renewable energy resources in the modern power grid can result in unsatisfactory frequency responses. To address this problem, wind turbine generators (WTGs), in particular, can be employed to support the power grid. Most works, however, only consider a simple step disturbance. In this paper, a new class of worst-case disturbances is introduced and their nefarious impact on renewable-penetrated power systems is investigated. The worst-case disturbances are derived using optimal control theory. More importantly, the proposed mechanism allows to determine the reaction time to trigger supportive control actions of WTGs to ensure satisfactory frequency response. Numerical results are provided and the effects of the worst-case disturbance on the reaction time are presented.

关键词： Frequency response Safety Power system stability Wind turbines Generators Optimal control

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Multivariate trace estimation in constant quantum depth

arXiv

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arXiv 2022年

作者： Quek, Yihui Kaur, Eneet Wilde, Mark M. Department of Mathematics Massachusetts Institute of Technology CambridgeMA02139 United States Dahlem Center for Complex Quantum Systems Freie Universität Berlin Berlin14195 Germany Information Systems Laboratory Stanford University Palo AltoCA94305 United States Cisco Quantum Lab Los Angeles United States Institute for Quantum Computing Department of Physics and Astronomy University of Waterloo WaterlooONN2L 3G1 Canada School of Electrical and Computer Engineering Cornell University IthacaNY14850 United States Hearne Institute for Theoretical Physics Department of Physics and Astronomy Center for Computation and Technology Louisiana State University Baton RougeLA70803 United States

There is a folkloric belief that a depth-Θ(m) quantum circuit is needed to estimate the trace of the product of m density matrices (i.e., a multivariate trace), a subroutine crucial to applications in condensed matter and quantum information science. We prove that this belief is overly conservative by constructing a constant quantum-depth circuit for the task, inspired by the method of Shor error correction. Furthermore, our circuit demands only local gates in a two dimensional circuit – we show how to implement it in a highly parallelized way on an architecture similar to that of Google’s Sycamore processor. With these features, our algorithm brings the central task of multivariate trace estimation closer to the capabilities of near-term quantum processors. We instantiate the latter application with a theorem on estimating nonlinear functions of quantum states with "well-behaved" polynomial approximations. © 2022, CC BY-NC-SA.

关键词： Polynomial approximation

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Assessing the viability of battery energy storage systems coupled with photovoltaics under a pure self-consumption scheme

arXiv

引用

arXiv 2019年

作者： Barzegkar-Ntovom, Georgios A. Chatzigeorgiou, Nikolas G. Nousdilis, Angelos I. Vomva, Styliani A. Kryonidis, Georgios C. Kontis, Eleftherios O. Georghiou, George E. Christoforidis, Georgios C. Papagiannis, Grigoris K. Department of Electrical and Computer Engineering Democritus University of Thrace Xanthi Greece Foss Research Centre for Sustainable Energy Pv Technology Laboratory Department of Electrical and Computer Engineering University of Cyprus Nicosia Power Systems Laboratory School of Electrical and Computer Engineering Aristotle University of Thessaloniki Thessaloniki Greece Department of Electrical and Computer Engineering University of Western Macedonia Kozani Greece

Over the last few decades, there is a constantly increasing deployment of solar photovoltaic (PV) systems both at the commercial and residential building sector. However, the steadily growing PV penetration poses several technical problems to electric power systems, mainly related to power quality issues. To this context, the exploitation of energy storage systems integrated along with PVs could constitute a possible solution. The scope of this paper is to thoroughly evaluate the economic viability of hybrid PV-and-Storage systems at the residential building level under a future pure self-consumption policy that provides no reimbursement for excess PV energy injected to the grid. For this purpose, an indicator referred to as the Levelized Cost of Use is utilized for the assessment of the competitiveness of hybrid PV-and-Storage systems in the energy market, considering various sizes of the hybrid system, battery energy storage costs and prosumer types for six Mediterranean countries. Copyright © 2019, The Authors. All rights reserved.

关键词： Battery storage

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Hysteresis Control of the Pseudo Boost PFC Converter

Hysteresis Control of the Pseudo Boost PFC Converter

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IEEE International Symposium on Industrial Electronics (ISIE)

作者： Aleksandra Lekić-Vervoort Milovan Majstorović Leposava Ristić Dušan Stipanović Intelligent Electrical Power Grids (IEPG) Electrical Sustainable Energy (ESE) Faculty of Electrical Engineering Mathematics and Computer Science TU Delft Delft Netherlands The Department of Power Converters and Drive Systems University of Belgrade Belgrade Serbia Coordinated Science Laboratory University of Illinois Urbana IL USA

ISBN: (数字)9781728156354

ISBN: (纸本)9781728156361

In this paper, a control design for the the Pseudo Boost PFC converter with the application in the charger for electric vehicles, is formulated and verified. The rectifier ends up being energy efficient because due to containing smaller number of switches. The converter is controlled using a method involving the minimum Lyapunov function derivative and a hysteresis. This control provides an averaged value of the converter sine input current, and thus, decreasing the THD value. Theoretical results are complemented with the corresponding simulations and experimental waveforms.

关键词： Hysteresis Switches Lyapunov methods Inductors Mathematical model Electric vehicles

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