Search results for "ABILITY"

showing 10 items of 18559 documents

Maximum Torque Per Ampere control algorithm for low saliency ratio interior permanent magnet synchronous motors

2017

This paper presents an investigation on the comparison between the Maximum Torque Per Ampere (MTPA) and the Field Orientation Control (FOC) algorithms for interior permanent magnet synchronous machines (IPMSMs). In particular, this study was carried out on a small-power IPMSM with low salience ratio. Both control algorithms have been implemented in the Matlab/Simulink environment, obtaining promising results.

010302 applied physicsControl algorithmMaximum torque per ampere control algorithmPermanent magnet synchronous motorComputer scienceRenewable Energy Sustainability and the Environment020208 electrical & electronic engineeringEnergy Engineering and Power Technology02 engineering and technologySettore ING-IND/32 - Convertitori Macchine E Azionamenti Elettrici01 natural sciencesField oriented control algorithmField orientationSalience (neuroscience)Control theoryMagnet0103 physical sciences0202 electrical engineering electronic engineering information engineeringInterior permanent magnet synchronous machineMATLABAmperecomputerMaximum torquecomputer.programming_language
researchProduct

A New Approach to Partial Discharge Detection Under DC Voltage: Application to Different Materials

2021

Usability of a new Direct Current Periodic waveform for partial discharge qualification in HVDC systems is exemplified by tests performed on different materials.

010302 applied physicsDC measurementsHVDCtesting methodbusiness.industryComputer sciencepattern recognitionDirect currentUsability01 natural sciencesElectronic Optical and Magnetic Materialspartial dischargeDc voltagedischarge phenomena0103 physical sciencesPattern recognition (psychology)Partial dischargeElectronic engineeringWaveformElectrical and Electronic EngineeringbusinessIEEE Electrical Insulation Magazine
researchProduct

Experimental Equipment for Studying the Residual Stresses Developed During High Temperature Reactions by X-Ray Diffraction

1996

This paper describes a device dedicated to studyng, by X-ray diffraction the residual stresses developed on surface samples as a function of temperature and atmosphere conditions. The setup consists of : a.) an horizontal axis goniometer which allows the programmed positionning of the sealed X-ray source and of the linear detector. b.) a high temperature controlled atmosphere chamber Particular attention has been paid to the thermal stability up to 1200°C and the accurate position on the sample.

010302 applied physicsDiffractionControlled atmosphereChemistrybusiness.industryDetectorGeneral Physics and Astronomy02 engineering and technology021001 nanoscience & nanotechnology01 natural sciencesAtmosphereOpticsResidual stressGoniometer[PHYS.HIST]Physics [physics]/Physics archives0103 physical sciencesX-ray crystallographyThermal stability0210 nano-technologybusiness
researchProduct

A fully-digital realtime SoC FPGA based phase noise analyzer with cross-correlation

2017

We report on a fully-digital and realtime operation of a phase noise analyzer using modern digital techniques with cross-correlation. With the advent of system on chip field-programmable gate arrays (SoC FPGAs) embedding hard core central processing unit, coprocessor and FPGA onto a single integrated circuit, the building of sensitive analysis devices for Time & Frequency research is made accessible at virtually no cost and benefits from reconfigurability. Used with high-speed digitizers we have successfully implemented a four-channel system whose preliminary results at 10 MHz shows a residual white noise floor < −185 dBrad2/Hz up to 5 MHz off the carrier, and flicker < −127 dBrad2/Hz using…

010302 applied physicsEngineeringSpectrum analyzerNoise measurementbusiness.industryReconfigurabilityIntegrated circuitWhite noise01 natural scienceslaw.inventionlaw0103 physical sciencesPhase noiseElectronic engineeringSystem on a chipField-programmable gate arraybusiness010301 acoustics2017 Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFC)
researchProduct

Partial discharges at different voltage waveshapes: Comparison between two different acquisition systems

2018

In modern HV apparatuses the wide use of electronic converters, increase the stress on the involved insulation systems and thus affect the reliability of the whole power grid. Additionally, such non-sinusoidal voltage shapes contain high gradient flanks that create problems in the detection of partial discharge (PD) activity. The aim of this paper is to discuss the methodology on how to suitably approach PD detection in insulation systems exposed to various voltage waveshapes in general by comparing two different measuring systems. The first one, equipped with a resonant PD decoupler, designed specifically for detection at typical power electronic waveshapes and the other one, based on an a…

010302 applied physicsFrequency responseMaterials sciencebusiness.industrySystem of measurement020208 electrical & electronic engineeringElectrical engineering02 engineering and technologyConverters01 natural sciencesPower (physics)Settore ING-IND/31 - ElettrotecnicaReliability (semiconductor)Partial discharge0103 physical sciencesPartial discharge0202 electrical engineering electronic engineering information engineeringmeasurementElectronicsElectrical and Electronic Engineeringbusinesssquare voltage waveformsVoltageIEEE Transactions on Dielectrics and Electrical Insulation
researchProduct

Production of Nano-Sized Co&lt;sub&gt;3&lt;/sub&gt;O&lt;sub&gt;4&lt;/sub&gt; by Pyrolysis of Organic Extracts

2016

The most promising application field of materials based on nano-sized Co3O4 is catalysis. The method of production is one of the factors, which greatly affects the catalytic activity of Co3O4 catalysts. The aim of this research is to study possibilities of a new promising extractive-pyrolytic method (EPM) for the production of Co3O4 nanopowders and silica- and ceria-supported Co3O4 nanocomposites. Solutions of cobalt hexanoate in hexanoic acid and trioctylammonium tetrachlorocobaltate in toluene preliminary produced by solvent extraction were used as precursors. The precursors’ thermal stability, phase composition, morphology and the magnetic properties of the final products of pyrolysis we…

010302 applied physicsHexanoic acidNanocompositeMaterials scienceMechanical EngineeringInorganic chemistrychemistry.chemical_element02 engineering and technology021001 nanoscience & nanotechnology01 natural sciencesTolueneCatalysischemistry.chemical_compoundChemical engineeringchemistryMechanics of Materials0103 physical sciencesGeneral Materials ScienceThermal stabilityCrystallite0210 nano-technologyCobaltPyrolysisKey Engineering Materials
researchProduct

Laser Ultrasonics Inspection for Defect Evaluation on Train Wheel

2019

Abstract Passengers’ safety and in-service life of wheelset axles play an important role in railway vehicles. For this reason, periodic inspections are necessary. Among non-destructive techniques, ultrasonic ones are widely applied in this field. The main disadvantage of conventional ultrasonic techniques is that the overall inspection of wheels requires the train to be put out-of-service and disassembly each part, which is time-consuming and expensive. In this paper, a non-conventional non-contact laser ultrasonic inspection for train wheels is proposed. The proposed method uses a laser interferometer to receive the ultrasonic wave without contact. The receiving system allows choosing the …

010302 applied physicsLaser ultrasonicsUltrasonic applications Ultrasonic waves Laser ultrasonicsComputer scienceMechanical EngineeringAcousticsUltrasonic testingNon-destructive testing Non-contact techniques Laser ultrasonic Train wheel inspectionCondensed Matter PhysicsLaser01 natural scienceslaw.inventionAxleInterferometrySettore ING-IND/14 - Progettazione Meccanica E Costruzione Di MacchineComplex geometrylaw0103 physical sciencesGeneral Materials ScienceUltrasonic sensor010301 acousticsReliability (statistics)
researchProduct

Melting temperature prediction by thermoelastic instability: An ab initio modelling, for periclase (MgO)

2021

Abstract Melting temperature (TM) is a crucial physical property of solids and plays an important role for the characterization of materials, allowing us to understand their behavior at non-ambient conditions. The present investigation aims i) to provide a physically sound basis to the estimation of TM through a “critical temperature” (TC), which signals the onset of thermodynamic instability due to a change of the isothermal bulk modulus from positive to negative at a given PC-VC-TC point, such that (∂P/∂V)VC,TC = -(∂2F/∂V2) VC,TC = 0; ii) to discuss the case of periclase (MgO), for which accurate melting temperature observations as a function of pressure are available. Using first princip…

010302 applied physicsMaterials scienceGeneral Chemical EngineeringAnharmonicity0211 other engineering and technologiesAb initioThermodynamics02 engineering and technologyGeneral ChemistryFunction (mathematics)engineering.material01 natural sciencesInstabilityComputer Science ApplicationsPhysical propertysymbols.namesakeThermoelastic dampingHelmholtz free energy0103 physical sciencessymbolsengineeringPericlase021102 mining & metallurgy
researchProduct

Long-term moisture absorption and durability of FRP pultruded rebars

2021

Abstract Up to 15-years long moisture diffusion into carbon, glass, and aramid fiber reinforced plastic (FRP) rebars is studied. To eliminate uncertainties in identification of the radial and axial diffusivities, a successive methodology for determination of the diffusion coefficients is proposed. The concept of apparent diffusivity taking into account anisotropy and edge effects is extended to cylindrical samples. The ratio of the axial and radial diffusivities is the lowest for carbon (3) and the highest for glass (81) FRP rebars. Durability performance of the rebars is estimated by monitoring their interlaminar shear strength (ILSS). Long-term exposure of FRP rebars in a humid environmen…

010302 applied physicsMaterials scienceMoisture02 engineering and technologyFibre-reinforced plastic021001 nanoscience & nanotechnologyThermal diffusivity01 natural sciencesDurabilityAramidPultrusion0103 physical sciencesDiffusion (business)Composite material0210 nano-technologyAnisotropyMaterials Today: Proceedings
researchProduct

Fabrication and characterization of low cost Cu 2 O/ZnO:Al solar cells for sustainable photovoltaics with earth abundant materials

2016

Abstract The low cost electrodeposition method was used to grow Cu2O thin films and experimentally determine the optimal absorber layer thickness. Raman scattering studies indicate the presence of solely crystalline Cu2O and SEM images show that the thin films consist of grains with a pyramidal shape. The influence of the thickness of the light absorbing Cu2O layer on the basic characteristic of the heterojunction and their properties have been investigated using reflectivity, current–voltage (J–V), capacitance–voltage (C–V) and the external quantum efficiency (EQE) measurements. The depletion layer, the charge collection length of the minority carrier, and reflectivity are the main factors…

010302 applied physicsMaterials scienceRenewable Energy Sustainability and the Environmentbusiness.industryOpen-circuit voltageHeterojunction02 engineering and technology021001 nanoscience & nanotechnology01 natural sciencesSurfaces Coatings and FilmsElectronic Optical and Magnetic Materialslaw.inventionOpticsDepletion regionlawPhotovoltaics0103 physical sciencesSolar cellOptoelectronicsQuantum efficiencyThin film0210 nano-technologybusinessShort circuitSolar Energy Materials and Solar Cells
researchProduct