- 标题
- 摘要
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- 实验方案
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[IEEE 2018 IEEE Power & Energy Society General Meeting (PESGM) - Portland, OR, USA (2018.8.5-2018.8.10)] 2018 IEEE Power & Energy Society General Meeting (PESGM) - Experimental Determination of PV Inverter Response to Grid Phase Shift Events
摘要： With the continued growth of renewable energy resources which interface to the electric grid via inverters, the understanding of such devices becomes ever more important to the safe and reliable operation of the bulk power system. This work investigates the specific response of a utility-scale PV inverter to grid voltage phase shift-type disturbances which sometimes occur during grid fault events. The role of the PV inverter’s phase-locked-loop (PLL) is identified as important to modeling the response. Switching-level simulations of a utility-scale PV inverter with a modeled PLL show a characteristic response when phase shift disturbances require the PLL to track what appear as fast frequency changes. Additionally, in this work a full-scale laboratory testing was carried out using the Opal real time (RT) OP5142 real time simulator and a large grid simulator to create phase shift disturbances with a high degree of repeatability. A photovoltaic (PV) inverter was connected to a grid simulator, and phase shifts were instantaneously implemented on the simulated grid, the results of the currents were then obtained. The experimental results obtained were validated with simulation results obtained from MATLAB/Simulink.
关键词： frequency response,photovoltaics,phase-locked loops,harmonics,inverter,DER
更新于2025-09-23 15:23:52
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Kalman Filtering Technique for Rooftop-PV System under Abnormal Grid Conditions
摘要： This paper presents a robust extended complex Kalman Filter (RECKF) based control for multifunctional double stage grid-connected solar photovoltaic array (SPVA) system. The main contributions of presented paper, include: 1) real power generation from SPVA fulfils the requirement of the connected loads and it provides the surplus power to the distribution network, 2) it behaves as a distribution static compensator, which performs various functionalities such as grid currents balancing, harmonics mitigation, unity power factor operation, 3) it is capable to operate under polluted grid scenarios such as under voltage, over voltage and imbalanced grid voltages. The SPVA feed-forward term is incorporated in the control technique to enhance the dynamic response of the system. The real coded particle swarm optimization (RCPSO) based metaheuristic approach is used for optimal tuning of the DC link voltage PI (Proportional Integral) controller. Simulation results illustrate the effectiveness of presented control algorithm under variations in point of common coupling (PCC) voltage. Test results illustrate the behaviour of grid-connected SPVA system subjected to various perturbations such as under voltages, over voltages, distorted and imbalanced grid voltages etc. The THDs (Total Harmonic Distortions) of grid currents are achieved well within recommended limits.
关键词： Power quality,Renewable energy,Solar photovoltaic array,Harmonics,VSC,Optimization
更新于2025-09-23 15:23:52
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Scalable appearance filtering for complex lighting effects
摘要： Realistic rendering with materials that exhibit high-frequency spatial variation remains a challenge, as eliminating spatial and temporal aliasing requires prohibitively high sampling rates. Recent work has made the problem more tractable, however existing methods remain prohibitively expensive when using large environmental lights and/or (correctly filtered) global illumination. We present an appearance model with explicit high-frequency micro-normal variation, and a filtering approach that scales to multi-dimensional shading integrals. By combining a novel and compact half-vector histogram scheme with a directional basis expansion, we accurately compute the integral of filtered high-frequency reflectance over large lights with angularly varying emission. Our approach is scalable, rendering images indistinguishable from ground truth at over 10× the speed of the state-of-the-art and with only 15% the memory footprint. When filtering appearance with global illumination, we outperform the state-of-the-art by ～ 30×.
关键词： glints,normal maps,summed area tables,spherical harmonics
更新于2025-09-23 15:23:52
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Contribution to the System Design of Contactless Energy Transfer Systems
摘要： In this contribution, a design procedure that is applicable to many kinds of wireless or contactless energy transfer systems is proposed. The design procedure is limited to near field wireless energy transfer systems in resonant operation. For this purpose, the input impedance and voltage transfer function of different natural frequencies are calculated analytically, and moreover, the behavior of the system is described. Following three issues lead to a readily applicable design procedure. First, the knowledge of the transfer functions. Secondly, the knowledge of basic magnetic properties and lastly, the known influence of harmonics according to rectifier and inverter. This design procedure is demonstrated with two hardware setups.
关键词： Inductive power transmission,power conversion harmonics,transfer functions,resonant inverters,inductive,charging
更新于2025-09-23 15:22:29
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[IEEE 2018 IEEE Energy Conversion Congress and Exposition (ECCE) - Portland, OR, USA (2018.9.23-2018.9.27)] 2018 IEEE Energy Conversion Congress and Exposition (ECCE) - Three-Phase AC-Stacked PV Inverter Architecture and Output Balancing Control Strategy with Battery under Asymmetrical Irradiance Conditions
摘要： This paper presents three-phase AC-stacked photovoltaic (PV) inverter architecture integrated with battery and its output balancing control strategy under asymmetrical irradiance conditions. The main objective of this research is to verify the feasibility of decentralized control scheme in the three-phase AC-stacked PV inverter system and mitigate unbalanced output power caused by asymmetrical irradiance conditions. To keep the benefits of the decentralized control, the proposed output balancing control strategy uses local measurement information captured by individual energy storage inverter members. The proposed system is demonstrated and verified through a control-hardware-in-the-loop test.
关键词： decentralized control,asymmetrical irradiance changes,three-phase grid-tied inverter,output balancing control,ac-stacked PV inverter,PR-controller based harmonics filter
更新于2025-09-23 15:22:29
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Voltage Quality Improvement Using Solar Photovoltaic System
摘要： Solar power and wind are the most promising distributed energy sources. The photovoltaic system has attracted significant attention in recent years. Although their benefits are numerous, they are known to create power quality issues, because of the power electronic converters they use. This paper investigates if there is a possibility to improve power quality only by connecting a solar photovoltaic system to the grid, and then gives results of on-site power quality measurements in the grid before and after the connection of the solar photovoltaic system.
关键词： Inverter,Active power filter,Voltage harmonics,Voltage unbalance,Voltage quality,Photovoltaic system
更新于2025-09-23 15:21:01
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Improvement of Ohmic Behavior of Back Contact in ZnSnP <sub/>2</sub> Solar Cells by Inserting Cu <sub/>3</sub> P
摘要： We propose a sampling scheme that can perfectly re- construct a collection of spikes on the sphere from samples of their lowpass-?ltered observations. Central to our algorithm is a gen- eralization of the annihilating ?lter method, a tool widely used in array signal processing and ?nite-rate-of-innovation (FRI) sam- pling. The proposed algorithm can reconstruct spatial samples. For large, this sampling require- ment improves over previously known FRI sampling schemes on the sphere by a factor of four. We showcase the versatility of the proposed algorithm by applying it to three problems: 1) sampling diffusion processes induced by localized sources on the sphere, 2) shot noise removal, and 3) sound source localization (SSL) by a spherical microphone array. In particular, we show how SSL can be reformulated as a spherical sparse sampling problem.
关键词： sparse sampling,spherical harmonics,sphere,Annihilation ?lter,?nite rate of innovavtion,diffusion sampling,shot noise removal,sound source localization
更新于2025-09-23 15:21:01
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Power Quality Improvement Utilizing PV Fed Unified Power Quality Conditioner Based on UV-PI and PR-R Controller
摘要： This paper presents control and configuration of photovoltaic fed unified power quality conditioner for the purpose of power quality enhancement. Literature studies convey that fixed PI gains used in the control schemes of Unified Power Quality Conditioners (UPQC) and PV-UPQC cannot easily adapt to various dynamic conditions. In this paper a novel online tunings method for PI control gains is adopted in the controllers of series and shunt converters of PV-UPQC. Unlike the previously implemented JAYA algorithm which has a single objective function utilized in the controller of DSTATCOM for improvement of only current quality, the new adaptive JAYA algorithm has two separate objective function, employed in shunt and series inverter control of PV-UPQC system for improvement of both current and voltage quality under various operational scenarios for power quality issues. The experimental results verify that implementation of JAYA based auto tuning PI controller increases the adaptivity of PV-UPQC system towards various dynamic conditions. Results obtained are compared with conventional optimization algorithms with fixed PI gains pertaining to a distribution system for validating its efficacy.
关键词： current harmonics,power quality,voltage sags/swells,PV-UPQC,Adaptive JAYA Optimization
更新于2025-09-23 15:21:01
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Analysis of Approaches for Modeling the Low Frequency Emission of LED Lamps
摘要： Light emitting diode (LED) lamps are now an established lighting technology, which is becoming prevalent in all load sectors. However, LED lamps are non-linear electrical loads, and their impact on distribution system voltage quality must be evaluated. This paper provides a detailed analysis of time domain and frequency domain approaches for developing and evaluating models suitable for use in large scale steady-state harmonic power ?ow analysis of the low frequency (LF) emission of LED lamps. The considered approaches are illustrated using four general categories of LED lamps, which have been shown to cover the vast majority of LED lamps currently available on the market. The aim is an in-depth assessment of the ability of commonly applied models to represent the speci?c design characteristics of different categories of LED lamps. The accuracy of the models is quantitatively evaluated by means of laboratory tests, numerical simulations, and statistical analyses. This provides an example, for each LED lamp category, of comprehensive information about the overall accuracy that can be achieved in the general framework of large scale LF harmonic penetration studies, particularly in the assessment of voltage quality in low voltage networks and their future evolution.
关键词： power system harmonics,component-based model,frequency-domain model,time-domain analysis,LED lamps
更新于2025-09-23 15:21:01
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Steering second-harmonics
摘要： The phase control and shaping of the second-harmonic radiation generated from an AlGaAs nanodisk antenna has now been accomplished by a team of researchers from Italy, France and Australia. Lavinia Ghirardini and co-workers used electron-beam lithography to fabricate a pair of gratings located either side of a nonlinear nanoantenna. Phase engineering then made it possible to redirect and control the emission angle of second-harmonic light generated from the optically pumped structure. The precise angle of emission can be engineered by employing gratings with different symmetry, or by varying the polarization of the optical pump beam. The control of the emission direction is important because it means that two orders of magnitude more power can be collected out of the antenna plane and arbitrary emission angles could be useful for certain applications. Another key point is that the AlGaAs structures can exhibit lower losses than metallic nanoantennas, which aid efficiency. Such efficient shaping of the nonlinear beams may have applications to, for example, single-photon sources and nonlinear imaging.
关键词： phase control,AlGaAs,nanoantenna,second-harmonics,nonlinear imaging
更新于2025-09-23 15:21:01