Ana B. M. Aguiar

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Electromagnetic modeling and simulation of hydroelectric generators require a large number of variables for accurate study and test result validation. Simulation results can be affected by mesh density, magnetic material properties, excitation current, and air gap. A finite-element analysis was performed to calculate the relative effect of these variables(More)
The hydroelectric generation industry faces two related challenges: increasing the output the existing hydro electrical generators but without reducing the reliability of these aging facilities. Many aspect of hydroelectric generator should be considered during any up-rate study. Magnetic losses of the stator and rotor core may change significantly with any(More)
The main objective of this paper is to determine the capability of the machine to operate at nominal load when some stator coils bars that are cut. Finite element electromagnetic simulations were carried out on an existing hydro generator of 32.5 MVA, 13.2 kV, 60 Hz, 68 poles, 432 stator slots, operating at nominal load with bypassed stator coil. The(More)
The predictions of the different magnetic core losses with acceptable accuracy are key parameters for temperature-rise calculations for any considered up-rate in large hydro electrical machines. In this paper, an overview of existing magnetic core loss models is reported. A new approach for the computation of the magnetic stator and rotor core loss is(More)
In this paper, Matlab and Stella softwares were used to compare the results of a daily simulation model of a micro combined heat and power system for residential purpose. From the load side, the model was based on consumer electrical and thermal load curves. On the other hand, from the power generation side, the model was based on the equations of(More)
The electromagnetic modeling and simulation of existing hydro electrical generators in operation always requires a large number of variables to carry out an accurate study and to be able to properly validate the different test results. Simulation can be affected by many parameters, such as: The air gap size (the design air gap is always different from the(More)
In the paper, the authors have investigated the natural gas based microturbine of residential complex with the Matlab. The aim of this work is to present a daily simulation model for technical and economical analysis of natural gas microturbine application for residential complex. The main advantage of this model is the timeframe that is used, which is(More)
the predictions of the induced current in the damper windings with acceptable accuracy are the key parameters for temperature-rise calculations damper windings for any considered up-rate of existing large hydro electrical machines. The measurement of the damper bar current is in most of case impossible because of the inaccessibility of these windings; where(More)
The predictions of the different magnetic core losses with acceptable accuracy are key parameters for temperature-rise calculations for any considered up-rate in large hydro electrical machines. It is common practice for hydro electrical designers to compute the core losses in different section of the machine function of the flux density given only at 60 Hz(More)
The aim of this work is to present a daily simulation model for future technical and economical analysis of natural gas microturbine for the ceramic industry. From the energy generation side, the model is based on the microturbine electrical and thermal efficiency. From the load side, the model is based on continuous load curves. The model was simulated in(More)