الفهرس 
CHAPTER (1): INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
In recent years, light-emitting diodes (LEDs) with their current performances have been proved to be the most suitable solution for replacing conventional lighting sources. Nowadays, a topic of interest in this context is the design for electronic driver in order to take the advantages of LEDʼs performances and powering them from universal AC input. The huge amount of energy consumed by lighting sources had led to more need for high efficiency, high power factor, regulated, small size and low cost drivers. All of these requirements with the low dynamic resistance of the LEDs and the need for high performance driver circuits push the designers to search for new solutions and better design considerations to take the advantages of LED lamps.
This thesis presents a high performance power converter for driving the LED lamps from universal input, including the design of the boost power factor correction (PFC) converter with hysteresis current control. The proposed converter operates in the continuous conduction mode (CCM), to solve the problems of using AC/DC converters with the LED lamp. Also, a boost PFC converter with hysteresis current control without using current sensor and other without using line voltage sensor are proposed to improve the performance and to reduce the total cost for the LED lamp driver.
The control algorithm of the proposed PFC converter can be implemented by using a low cost digital signal processor (DSP) or microprocessor to achieve high switching frequency. The proposed control achieves a near unity power factor under the steady-state and transient operating conditions.
Simulation results for the proposed system using ”MATLAB/SIMULINK” software show that the hysteresis control has low total harmonic distortion (THD), high power factor (PF), high switching frequency, lower cost and better performance. Furthermore, a sinusoidal input current with low THD can be achieved under a distorted input voltage. The prototypes of boost PFC for driving the LED lamps,
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controlled by a DSP 1104 evaluation board, were built and tested in the laboratory. Experimental results show that the proposed system achieves a sinusoidal input current waveform for both steady-state and transient operating conditions.