Search results for " LIMITER"

showing 10 items of 13 documents

A symmetric nonlocal damage theory

2003

The paper presents a thermodynamically consistent formulation for nonlocal damage models. Nonlocal models have been recognized as a theoretically clean and computationally efficient approach to overcome the shortcomings arising in continuum media with softening. The main features of the presented formulation are: (i) relations derived by the free energy potential fully complying with nonlocal thermodynamic principles; (ii) nonlocal integral operator which is self-adjoint at every point of the solid, including zones near to the solid's boundary; (iii) capacity of regularizing the softening ill-posed continuum problem, restoring a meaningful nonlocal boundary value problem. In the present app…

Continuum (measurement)Applied MathematicsMechanical EngineeringMathematical analysisNonlocal boundaryTangentLocalization limiterCondensed Matter PhysicsNonlocal damageAssociative damageModuliQuantum nonlocalityMechanics of MaterialsModeling and SimulationThermodynamicsGeneral Materials ScienceTangent stiffness matrixSettore ICAR/08 - Scienza Delle CostruzioniSofteningAssociative propertyMathematicsInternational Journal of Solids and Structures
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Currents Distribution During a Fault in an MV Network: Methods and Measurements

2016

When a single line to ground fault happens on the MV side of a HV/MV system, only a small portion of the fault current is injected into the ground by the ground-grid of the faulty substation. In fact the fault current is distributed between grounding electrodes and MV cables sheaths. In systems with isolated neutral or with resonant earthing this may be sufficient to provide safety from electric shock. Experimental measurements were performed on a real MV distribution network: a real single line to ground fault was made and fault currents were measured in the faulty substation and in four neighboring substations. In this paper the problem of fault current distribution is introduced, the tes…

EngineeringDistribution (number theory)020209 energyGlobal earthing system02 engineering and technologyglobal earthing systemsFault (power engineering)Industrial and Manufacturing EngineeringFault current limiter0202 electrical engineering electronic engineering information engineeringmedicineCurrent distributionElectrical and Electronic EngineeringElectrical conductorsingle line to ground faultglobal earthing systems (GESs)Current distribution electrical safety global earthing systems (GESs) grounding power distribution faults power system faults single line to ground fault (SLGF)business.industryGroundElectric shockElectrical engineeringpower system faultsgroundingmedicine.diseaseGridSingle linecurrent distribution; electrical safety; global earthing systems; grounding; power distribution faults; power system faults; single line to ground fault; control and systems engineering; industrial and manufacturing engineering; electrical and electronic engineeringSettore ING-IND/33 - Sistemi Elettrici Per L'EnergiaSettore ING-IND/31 - ElettrotecnicaPower system faultControl and Systems Engineeringsingle line to ground fault (SLGF)power distribution faultselectrical safetybusinessCurrent distribution; electrical safety; global earthing systems (GESs); grounding; power distribution faults; power system faults; single line to ground fault (SLGF); Control and Systems Engineering; Industrial and Manufacturing Engineering; Electrical and Electronic EngineeringPower distribution fault
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Arc Fault Detection Method Based on CZT Low-Frequency Harmonic Current Analysis

2017

This paper presents a method for the detection of series arc faults in electrical circuits, which has been developed starting from an experimental characterization of the arc fault phenomenon and an arcing current study in several test conditions. Starting from this, the authors have found that is it possible to suitably detect arc faults by means of a high-resolution low-frequency harmonic analysis of current signal, based on chirp zeta transform, and a proper set of indicators. The proposed method effectiveness is shown by means of experimental tests, which were carried in both arcing and nonarcing conditions and in the presence of different loads, chosen according to the UL 1699 standard…

Engineeringarc fault detection020209 energyseries arcsArc-fault circuit interrupter02 engineering and technologyUL 1699Fault detection and isolationlaw.inventionHarmonic analysisElectric arcarc fault circuit interrupter (AFCI)Arc dischargeslawArc discharges arc fault circuit interrupter (AFCI) arc fault detection electrical safety fault diagnosis home protection interrupters power system harmonics power system measurements series arcs UL 1699Fault current limiterhome protection0202 electrical engineering electronic engineering information engineeringElectronic engineeringElectrical and Electronic EngineeringInstrumentationpower system harmonicsinterruptersbusiness.industry020208 electrical & electronic engineeringfault diagnosispower system measurementsFault indicatorElectrical networkHarmonicelectrical safetybusinessSettore ING-INF/07 - Misure Elettriche E Elettroniche
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Reducing DC Link Voltage Unbalance in a Fault-Tolerant Inverter

2014

Today, continuous working of power inverter drives is mandatory for several applications. Damages to materials, machines or even risks to human life have to be absolutely avoided. In the literature, fault-tolerant algorithms and architectures to achieve a successful fault handling are investigated. Researchers aim at reducing the number and cost of additional components, improving at the same time the inverter performances under postfault conditions. Cost, post-fault power derating and increasing distortion are usually conflicting requirements. In this paper, a fault-tolerant three phase inverter is presented. A reconfigurable architecture and a novel fault-tolerant algorithm is designed to…

Engineeringbusiness.industryDc link voltageFault current limiterElectronic engineeringInverterFault toleranceSettore ING-IND/32 - Convertitori Macchine E Azionamenti ElettricibusinessPower electronics Power converters AC motor drives fault-tolerant Inverter
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Control of solid-state fault current limiter for DG-integrated distribution systems

2017

Fault current limier (FCL) is a device that limits the system current under fault conditions without disconnecting the system and affecting the power system protection components such as circuit breakers. Many types of FCLs have been proposed to limit the magnitude of the fault current. Solid-state fault current limiters (SSFCLs) can limit the peak value of the fault current by applying several methods, such as controlling the system impedance or controlling the voltage that appears across the fault. In this paper, a new control scheme for the SSFCL circuit is presented. The control method is based on controlling the duty cycle of solid state switches to control the rms value of the system …

Engineeringdistributed generationbusiness.industrySolid-state relay020208 electrical & electronic engineeringHardware_PERFORMANCEANDRELIABILITY02 engineering and technologyFault (power engineering)01 natural sciencesFault indicatorSettore ING-IND/33 - Sistemi Elettrici Per L'EnergiaControl theoryDuty cycleduty cycle0103 physical sciencesFault current limiter0202 electrical engineering electronic engineering information engineeringElectronic engineering010306 general physicsbusinessPower-system protectionsolid state fault current limiterElectrical impedanceCircuit breakerFault current limiter2017 IEEE International Conference on Environment and Electrical Engineering and 2017 IEEE Industrial and Commercial Power Systems Europe (EEEIC / I&CPS Europe)
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Current and Voltage Behaviour During a Fault in a HV/MV System: Methods and Measurements

2015

When a single line to ground fault happens on the MV side of a HV/MV system, only a small portion of the fault current is injected into the ground by the ground-grid of the faulty substation. In fact the fault current is distributed between grounding electrodes and MV cables sheaths. In systems with isolated neutral or with resonant earthing this may be sufficient to provide safety from electric shock. Experimental measurements were performed on a real MV distribution network: a real single line to ground fault was made and fault currents were measured in the faulty substation and in four neighbouring substations. In this paper the problem of fault current distribution is introduced, the te…

Engineeringelectrical and electronic engineeringGlobal earthing systemCurrent distribution; Electrical safety; Global earthing systems; grounding; Power distribution faults; Single line to ground faultHardware_PERFORMANCEANDRELIABILITYFault (power engineering)Fault current limiterElectronic engineeringmedicineGlobal earthing systemscurrent distribution; electrical safety; global earthing systems; grounding; power distribution faults; single line to ground fault; electrical and electronic engineering; energy engineering and power technologyenergy engineering and power technologyCurrent distributionPower distribution faultsElectrical safetySingle line to ground faultElectric shockGroundbusiness.industryElectrical engineeringgroundingSingle linemedicine.diseaseEarthing systemSettore ING-IND/33 - Sistemi Elettrici Per L'EnergiaSettore ING-IND/31 - ElettrotecnicaCurrent (fluid)businessPower distribution faultVoltage
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Studio termomeccanico del modulo Limiter del reattore ITER-FEAT

2002

FUSIONE NUCLEARE MODULO LIMITER
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Thermal Parametric and Thermo-Mechanical analyses for the Limiter Blanket Module of ITER

1996

NUCLEAR FUSION ITER LIMITER
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Thermal solitons along wires with flux-limited lateral exchange

2021

We obtain some exact solutions in the context of solitons, for heat conduction with inertia along a cylinder whose heat exchange with the environment is a non-linear function of the difference of temperatures of the cylinder and the environment, due to a flux-limiter behavior of the exchange. We study the consequences of heat transfer and information transfer along the wire, and we compare the situation with analogous solitons found in nonlinear lateral radiative exchange studied in some previous papers. We also find further exact solutions in terms of Weierstrass elliptic functions for the sake of completeness.

PhysicsHeat waves. Thermal solitons. Heat flux saturation. Maxwell-Cattaneo law. Radiative transfer. Auxiliary equation method. Flux limiters.media_common.quotation_subjectElliptic functionStatistical and Nonlinear PhysicsContext (language use)MechanicsInertiaThermal conductionNonlinear systemHeat transferRadiative transferCylinderMathematical Physicsmedia_common
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Analysis of Torque Developed in Axial Flux, Single-Phase Brushless DC Motor With Salient-Pole Stator

2004

An analysis of the torque developed by a single-phase disc brushless permanent magnet motor with salient-pole stator is presented. The machine represents a new family of brushless disc motors with the starting torque issue appearing to be most challenging. To produce a starting torque, the permanent magnets on one of the rotor discs are distributed nonuniformly. However, this significantly distorts a shape of the cogging torque versus rotational angle characteristic which, in turn, affects a waveform of the overall torque. A three-dimensional (3-D) finite-element model is used for the purpose of determining of angular variations of the torque developed by the motor. To find how the torque v…

PhysicsStall torqueTorque motorCogging torqueEnergy Engineering and Power TechnologyControl engineeringQuantitative Biology::Subcellular ProcessesTorque limiterDirect torque controlControl theoryTorque sensorAstrophysics::Earth and Planetary AstrophysicsElectrical and Electronic EngineeringDamping torqueSynchronous motorIEEE Transactions on Energy Conversion
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