Search results for "variable load"

showing 2 items of 2 documents

On thermoeconomics of energy systems at variable load conditions: integrated optimization of plant design and operation

2007

Abstract Thermoeconomics has been assuming a growing role among the disciplines oriented to the analysis of energy systems, its different methodologies allowing solution of problems in the fields of cost accounting, plant design optimisation and diagnostic of malfunctions. However, the thermoeconomic methodologies as such are particularly appropriate to analyse large industrial systems at steady or quasi-steady operation, but they can be hardly applied to small to medium scale units operating in unsteady conditions to cover a variable energy demand. In this paper, the fundamentals of thermoeconomics for systems operated at variable load are discussed, examining the cost formation process an…

ExergyEngineeringPrimary energyRenewable Energy Sustainability and the Environmentbusiness.industryThermoeconomics has been assuming a growing role among the disciplines oriented to the analysis of energy systems its different methodologies allowing solution of problems in the fields of cost accounting plant design optimisation and diagnostic of malfunctions. However the thermoeconomic methodologies as such are particularly appropriate to analyse large industrial systems at steady or quasisteady operation but they can be hardly applied to small to medium scale units operating in unsteady conditions to cover a variable energy demand. In this paper the fundamentals of thermoeconomics for systems operated at variable load are discussed examining the cost formation process and separately the cost fractions related to capital depreciation (which require additional distinctions with respect to plants in steady operation) and to exergy consumption. The relevant effects of the efficiency penalty due to off design operation on the exergetic cost of internal flows are also examined. An original algorithm is proposed for the integrated optimization of plant design and operation based on an analytical solution by the Lagrange multipliers method and on a multi-objective decision function expressed either in terms of net cash flow or primary energy saving. The method is suitable for application in complex energy systems such as ‘‘facilities of components of a same product’’ connected to external networks for power or heat distribution. For demonstrative purposes the proposed thermoeconomically aided optimization is performed for a grid connected trigeneration system to be installed in a large hotel.Energy Engineering and Power TechnologyCost accountingThermoeconomicsGridEnergy conservationVariable (computer science)symbols.namesakeFuel TechnologyNuclear Energy and EngineeringLagrange multipliersymbolsProcess engineeringbusinessSimulation

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Mixed Fault Classification of Sensorless PMSM Drive in Dynamic Operations Based on External Stray Flux Sensors

2022

This paper aims to classify local demagnetisation and inter-turn short-circuit (ITSC) on position sensorless permanent magnet synchronous motors (PMSM) in transient states based on external stray flux and learning classifier. Within the framework, four supervised machine learning tools were tested: ensemble decision tree (EDT), k-nearest neighbours (KNN), support vector machine (SVM), and feedforward neural network (FNN). All algorithms are trained on datasets from one operational profile but tested on other different operation profiles. Their input features or spectrograms are computed from resampled time-series data based on the estimated position of the rotor from one stray flux sensor t…

Support Vector Machinedemagnetisationinter-turn short circuitChemical technologydemagnetisation; inter-turn short circuit; machine learning; permanent magnet synchronous motor; variable speed; variable loadTP1-1185BiochemistryAtomic and Molecular Physics and OpticsAnalytical ChemistryComputingMethodologies_PATTERNRECOGNITIONmachine learningpermanent magnet synchronous motorvariable speedVDP::Teknologi: 500::Maskinfag: 570Magnetsvariable loadNeural Networks ComputerSupervised Machine LearningElectrical and Electronic EngineeringInstrumentationAlgorithmsSensors (Basel, Switzerland)

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