Electronic and Communication - Engineering

Abstract: Microwave power transistors made of conventional semiconductors have already approached their performance limit. In order to meet the future needs of wireless communication systems, research efforts are directed to wide bandgap semiconductors such as GaN. The combined merits of high power and high speed can be achieved using High Electron Mobility Transistors (HEMTs) made of AlGaN/GaN materials system. In this work, presents both one-dimensional and two-dimensional models to assess the static characteristics of AlGaN/GaN HEMT.

Abstract: A control algorithm is basically a mapping that maps the controller_s input values into output values. This mapping can be specified by analytical equations, decision trees, fuzzy rules, neural networks, or a combination.

Abstract : This thesis deals with the analyses of UPS system and how the output voltage of the UPS can be stabilized at a certain Level, also it studies the performance parameters of the converters included in the UPS system (rectifier and inverter). For the three-phase bridge rectifier, the harmonic components present in the output voltage waveform of the three-pulse, six-pulse and twelve-pulse are investigated. It is found that the orders of the generated harmonics are the same, but the amplitudes of these harmonics decrease with increase of number of pulses.