Search results for "GRID"

showing 10 items of 792 documents

Decoupled control scheme of the grid-connected split-source inverter for renewable energy sources

2016

Grid-connected power conversion systems for renewable energy sources must fulfill several requirements, including high efficiency, reduced cost and complexity, and, quite often, also boost capabilities from the dc sources to the ac power grid. For such applications, single-stage power converters with boost capabilities offer some potential advantages. Among several proposed options, split-source inverter (SSI) has been recently investigated. This paper proposes a decoupled control scheme for the SSIs, where the common mode term of the ac modulation signals is used to control the dc input current. Thus, the dc input current and ac output current can be controlled independently. The proposed …

EngineeringGrid connection; Renewable energy sources; Single-stage; Split-source inverter; Voltage source inverter; Z-source inverter; Control and Systems Engineering; Electrical and Electronic EngineeringRenewable energy source02 engineering and technologySettore ING-INF/01 - ElettronicaRenewable energy sourcesSplit-source inverter0202 electrical engineering electronic engineering information engineeringGrid connectionSingle-stageElectrical and Electronic EngineeringVoltage source inverterbusiness.industryGrid connection020208 electrical & electronic engineeringElectrical engineering020206 networking & telecommunicationsZ-source inverterAC powerConvertersGridRenewable energyPower (physics)Control and Systems EngineeringInverterbusinessZ-source inverter
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Microgrid supervisory controllers and energy management systems:A literature review

2016

Abstract Microgrids (MGs), featured by distributed energy resources, consumption and storage, are designed to significantly enhance the self-sustainability of future electric distribution grids. In order to adapt to this new and revolutionary paradigm, it is necessary to control MGs in intelligent and coordinated fashion. To this aim, a new generation of advanced Microgrid Supervisory Controllers (MGSC) and Energy Management Systems (EMS) has emerged. The aim of this paper is to summarize the control objectives and development methodologies in the recently proposed MGSC/EMS. At first, a classification of control objectives is made according to the definition of hierarchical control layers i…

EngineeringHierarchical controlOperations researchMicrogridRenewable Energy Sustainability and the Environmentbusiness.industryEnergy management020209 energyControl (management)02 engineering and technologyMaximum power point trackingSettore ING-IND/33 - Sistemi Elettrici Per L'EnergiaEnergy management systemSCADAInformation and Communications TechnologyDistributed generation0202 electrical engineering electronic engineering information engineeringSystems engineeringMicrogridMicrogrid supervisory controllerEnergy management systembusiness
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Manufacturing tolerances effects on PV array energy production

2014

This paper investigates the tolerance effects of commercial photovoltaic modules in terms of electrical energy reduction of photovoltaic plants. Several commercial modules, having the same rated power, present different power tolerance values. A wide tolerance is an indicator of possible defects or differences in the production process and is responsible of remarkable reductions in the electricity production of photovoltaic plants. In this paper, thanks to the development of a suitable simulation tool, several simulations have been carried out, considering different tolerance and shading conditions for the PV array. Simulation results quantify the peak power value of the different plant con…

EngineeringI-V characteristicManufacturing toleranceEquationbusiness.industryElectric potential energyPhotovoltaic systemPV module defectArrayProductionSettore ING-IND/32 - Convertitori Macchine E Azionamenti ElettriciAutomotive engineeringStandardPower ratingElectricity generationMathematical modelElectronic engineeringGrid-connected photovoltaic power systemRooftop photovoltaic power stationbusinessmismatchPhotovoltaic systemNominal power (photovoltaic)
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New Measurement Procedure for Load Flow Evaluation in Medium Voltage Smart Grids

2013

The aim of this paper is to present a new approach for the medium voltage (MV) distribution network load flow analysis, mainly based on power measurement at the low voltage (LV) level of MV/LV distribution substations. This allows to use measurement instruments, usually already installed in the secondary substations, thus achieving an equally reliable measurement system with a lower cost compared to measurements at the MV side. The new approach can be applied using a proper communication system to collect the nodal measurements and an iterative algorithm based on ladder iterative technique (LIT) to compute the load flow. The validity of this method is presented and discussed on the basis of…

EngineeringIterative methodbusiness.industrypower system measurementSystem of measurementSmart grid (SG) power system measurements load flow power quality analyzer (PQA) state estimation (SE) advanced metering infrastructure (AMI)substations.Communications systemautomatic meter readingpower distribution reliabilityPower (physics)Settore ING-IND/33 - Sistemi Elettrici Per L'Energiasmart power gridsSmart gridElectronic engineeringload flowiterative methodsPower-flow studybusinessLow voltageSettore ING-INF/07 - Misure Elettriche E ElettronicheVoltagepower system state estimation
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Genetic Algorithm Optimized Grid-based RF Fingerprint Positioning in Heterogeneous Small Cell Networks

2015

In this paper we propose a novel optimization algorithm for grid-based RF fingerprinting to improve user equipment (UE) positioning accuracy. For this purpose we have used Multi-objective Genetic Algorithm (MOGA) which enables autonomous calibration of gridcell layout (GCL) for better UE positioning as compared to that of the conventional fingerprinting approach. Performance evaluations were carried out using two different training data-sets consisting of Minimization of Drive Testing measurements obtained from a dynamic system simulation in a heterogeneous LTE small cell environment. The robustness of the proposed method has been tested analyzing positioning results from two different area…

EngineeringKullback-Leibler divergencebusiness.industryReal-time computingFingerprint recognitionGridmulti-objective genetic algorithmminimization of drive testsUser equipmentRobustness (computer science)Genetic algorithmElectronic engineeringgrid-based RF fingerprintingMinificationSmall cellRadio frequencybusiness
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Six-years-long effects of the Italian policies for photovoltaics on the grid parity of grid-connected photovoltaic systems installed in urban contexts

2017

Abstract The purpose of this study is investigating the grid parity (GP) time and the levelized cost of energy (LCOE) of grid-connected photovoltaic (PV) systems installed in densely urbanized contexts. The analysis, which was elaborated for three Italian cities, considered the effects of the promoting policies enacted by the Italian government from June 2010 to May 2016. An appropriate methodology was applied with the aim of realistically defining the energy produced by PV systems installed on buildings with different roof types and number of floors. The calculus of the disbursements considered the operating, maintenance and insurance costs and the wear of PV panels and inverters. The resu…

EngineeringLevelized cost of energy020209 energy02 engineering and technologyTax creditIndustrial and Manufacturing EngineeringGrid parityEnergy analysiPhotovoltaics0202 electrical engineering electronic engineering information engineeringElectrical and Electronic EngineeringCost of electricity by sourceRoofCivil and Structural EngineeringSettore ING-IND/11 - Fisica Tecnica Ambientalebusiness.industryMechanical EngineeringPhotovoltaic systemBuilding and ConstructionEnvironmental economicsInvestment (macroeconomics)GridPollutionFeed-in tariffGrid parityEnergy (all)General EnergyLoanbusinessTelecommunicationsPhotovoltaicEnergy
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Optimization of photovoltaic energy production through an efficient switching matrix

2013

This work presents a preliminary study on the implementation of a new system for power output maximization of photovoltaic generators under non-homogeneous conditions. The study evaluates the performance of an efficient switching matrix and the relevant automatic reconfiguration control algorithms. The switching matrix is installed between the PV generator and the inverter, allowing a large number of possible module configurations. PV generator, switching matrix and the intelligent controller have been simulated in Simulink. The proposed reconfiguration system improved the energy extracted by the PV generator under non-uniform solar irradiation conditions. Short calculation times of the pro…

EngineeringMPPTPhotovoltaic modulesEnergy Engineering and Power TechnologyDynamic electrical schemeEnvironmental Science (miscellaneous)lcsh:Technologylcsh:HD72-88Maximum power point trackinglcsh:Economic growth development planningPV systemsGenerator (circuit theory)Matrix (mathematics)Control theoryGrid-connected photovoltaic power systemElectronic engineeringPV systems; Photovoltaic modules; Mismatch; Optimization algorithm; Reconfiguration; MPPT; Dynamic electrical schemeWater Science and Technologylcsh:TRenewable Energy Sustainability and the Environmentbusiness.industryPhotovoltaic systemControl reconfigurationControl engineeringPV systems Photovoltaic modules Mismatch Optimization algorithm Reconfiguration MPPT Dynamic electrical schemeSettore ING-IND/33 - Sistemi Elettrici Per L'EnergiaOptimization algorithmSettore ING-IND/31 - ElettrotecnicaMismatchReconfigurationInverterbusinessJournal of Sustainable Development of Energy, Water and Environment Systems
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Electrostatic synchronous generator model of an Inverter-Based Distributed Generators

2015

In this paper, the idea of modelling the Inverter-Based Distributed Generators by using the concept of Electrostatic synchronous machines is discussed. A mathematical model of the inverter has been established which depends on the dc bus voltage, modulation index and frequency of the system. Two mathematical models have been developed: a small signal model and a steady-state model. These mathematical models will be helpful in studying the stability of a microgrid; especially when studying the transient stability performance of on-grid operation of converter-based distributed generator with multi-machine microgrid. Simulation results using Matlab/Simulink are carried out.

EngineeringMathematical modelMicrogridbusiness.industryRenewable Energy Sustainability and the EnvironmentModulation indexEnergy Engineering and Power TechnologyPermanent magnet synchronous generatorDistributed GeneratorSmall-signal modelStability of microgridSettore ING-IND/33 - Sistemi Elettrici Per L'EnergiaComputer Science::Hardware ArchitectureElectrostatic Synchronous MachineElectronic engineeringInverterMicrogridTransient (oscillation)businessMATLABcomputercomputer.programming_language
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Economic analysis on dynamic photovoltaic systems in new Italian “feed in tariffs” context

2013

Dynamic photovoltaic generators, based on the application of solar-trackers, are able to give an increment to the electric energy production from solar source. Their realization and maintenance costs are certainly higher than those of fixed ones. In this paper the Authors propose a method to estimate the increment of electrical energy generation that must be guaranteed by a dynamic photovoltaic generator, so as its realization could be more favorable with respect to that of a fixed generator one with the same rated power. This method, developed by means of classical economic indexes like the Pay-Back-Period and the Net Present Value, takes in to account the economic incentives for the PV sy…

EngineeringMathematical optimizationPower ratingbusiness.industryPhotovoltaicsPhotovoltaic systemGrid-connected photovoltaic power systemElectrical engineeringContext (language use)businessActivity-based costingFeed-in tariffMaximum power point tracking2013 International Conference on Clean Electrical Power (ICCEP)
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Robust Multi-Objective Optimal dispatch of Distributed Energy Resources in Micro-Grids

2011

Modern distribution systems are implemented through micro grids: small power networks where generation is close to consumption and ICT supports the coordinated management of the different energy resources. In such systems, the central control unit manages energy dispatch from the different sources according to different criteria (technical, economical and environmental) and takes care of tertiary regulation. Such optimization for the tertiary regulation is performed with a time interval that typically is of 24 hours. This is due to the fact that it is necessary to take into account the charge and discharge cycles of storage systems. On the other hand, such long time leads to large errors in…

EngineeringMathematical optimizationbusiness.industryEconomic dispatchEnergy consumptionMulti-objective optimizationSettore ING-IND/33 - Sistemi Elettrici Per L'EnergiaElectricity generationRobustness (computer science)Load regulationDistributed generationbusinessEnergy sourceMultiobjective optimization microgrids optimal management roust solutions.
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