Jehan Hassan Shazly

Heat Conduction Problems in

In this paper, the finite-element method is used to perform heat transfer analysis to obtain the steady state and the transient temperature distribution of gas cooled-insulated power transformers. All significant parameters that influence transformer operation have been included. Also, the analysis results, which are obtained from the thermal analysis, could be reviewed at any specified location within the transformer as a function of time. The predicted temperature values are compared with experimental results reported in the literature.

{\rm SF}_{6}

paper presents the implementation of a generalized photovoltaic simulation model using MATLAB®/GUI interface. The model is developed using basic circuit equations of the Photovoltaic (PV) cells including the effects of solar radiation and temperature changes. These effects added in real time operation simultaneously. Since the PV module has nonlinear characteristics, it is necessary to model it for the design and simulation of maximum power point for such system applications. Photovoltaic system characteristic curves as current - voltage (I-V) and power - voltage (P-V) characteristics are drawn according to values change of the temperature and solar radiation which observed in MATLAB®/GUI interface. The simulation results showed that these factors and the corresponding PV model influence the maximum power obtained from PV modules under operating conditions. The simulation model also presented the design of the array and the batteries of the load connected to the photovoltaic system.

Gas Cooled-Insulated Power Transformers Solved by the Finite-Element Method

The effects of cooling methods, gas pressure, gas velocity, electrical loading, and environmental parameters on the steady-state temperature distribution of SF6 gas-cooled-insulated power transformers are investigated by using the finite-element method. The contributions of convection and radiation to the total heat-transfer rate inside and outside the transformer are included. The results provide useful sensitivity information which can be accessed and manipulated by the transformer designers or operators. This sensitivity information significantly reduces the analysis and computations via identifying the important parameters that most affect the temperature distribution in this type of transformer.

A Photovoltaic (Cell, Module, Array) Simulation and Monitoring Model using MATLAB®/GUI Interface

It is important to study the thermal performance of electric machines which depends on many variables, one of them is the motor speed. In this paper, the effect of changing the speed is studied, with maintaining the other parameters, by analyzing a 3D thermal model of an axial flux permanent magnet synchronous motor (AFPMSM) and solving steady state heat conduction equations with finite elements (FE). Comparison between the resulted temperature values of the motor at each part due to various rotor speeds is performed.