الفهرس 
Potential sources of harmonicsOnly 14 pages are availabe for public view
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Abstract
Over the last decades, applications of AC voltage regulators have been widely spread. The features of high efficiency, high power factor, reliable, small size and cost effective have become essential for any voltage regulator proposed. These requirements increase the care of the design of AC voltage regulators. Therefore, this thesis presents a configuration of both a three-phase AC-AC buck and boost voltage regulators to operate with a three phase inductive loads which have a reduced number of controlled switches. A proposed control methodology is proposed to provide regulated AC output voltage with a simple control and excellent performance. The proposed circuits have high efficiency for adjusting AC power; because it is composed of fewer switches. The proposed regulators restrain more harmonics of output voltage and the input current flows continuously, thus a nearly unity input power factor is achieved, Also harmonics of input current and load current are almost negligible. The control algorithm of the proposed regulators could be implemented by using a low cost digital signal processor (DSP) or microprocessor to achieve high switching frequency. The proposed control achieves a nearly unity power factor under the steady-state and transient operating conditions. Simulation results for the proposed system using ”MATLAB/SIMULINK” software show that the input current has a low total harmonic distortion (THD), high power factor (PF), lower cost and better performance. Furthermore, a sinusoidal input current can be achieved under a distorted input voltage. The prototypes of the proposed regulators, controlled by a DSP 1104 evaluation board, were built and tested in the laboratory. Experimental results confirmed the simulation results achieving a sinusoidal input current waveform with unity input power factor for both steady-state and transient operating conditions.