الفهرس | Only 14 pages are availabe for public view |
Abstract The rectifier followed by DC regulator has been a well-established power converter configuration for many industrial applications. The increasing costs of utility on utility usage and the need to improve voltage quality have increased the interest in the development of power electronic equipment with power factor control capability. The features of high efficiency, high power factor, small size and cost effects have become essential for any voltage regulator proposed. Therefore, this thesis presents a three-phase AC-DC rectifier followed by DC regulator to improve input power factor with only one controlled switch. A proposed control strategy is used to provide regulated DC output voltage with a simple control and excellent performance. This study is applied for boost and CUK converters. The proposed circuits have high efficiency for adjusting DC power; because it is composed of only one switch. The proposed regulator restrain more harmonics of output voltage and the input current flows continuously, thus a nearly unity input power factor is achieved; Also harmonics of the input current and load current are almost negligible. The control strategy of the regulator could be implemented by using a digital signal processor (DSP) or microprocessor to achieve high switching frequency. Simulation results for the system under consideration show that the proposed control has low total harmonic distortion THD, nearly unity PF, lower cost and better performance. Furthermore, a sinusoidal input current with low THD can be achieved. The simulation results for static load are studied in both transient and steady-state operations. The prototypes of boost PFC for static load controlled by a DSP-1104 evaluation board were built and tested in the laboratory. The experimental results show that the proposed PFC control method can achieve sinusoidal input current waveform for both transient and steady-state operations. The simulation results are proved the good agreement when compared with the relevant experimental results. |