الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
To overcome the harmonic problems in the non-linear systems, the thesis used three different loads to represent the effect of the harmonics on the source currents. First, it is applied on the three-phase source voltages connected with uncontrolled diode bridge rectifier which connected with inductive-resistive load. The PI-controller parameters are optimized by bacterial foraging optimization (BFO). The results proved that the proposed SAPF with PI-controller based on-line BFO is robust, reliable and contributes to harmonics mitigation. Also, it improves PF correction and power quality enhancement of electric grid when it is compared with the system without the SAPF and with the SAPF controlled by classical PI- controller. Second, SAPF is applied on the three-phase source voltages connected with uncontrolled diode bridge rectifier which is connected with inductive-resistive load. The PI-controller parameters are optimized by particle swarm optimization (PSO). The results show that the system without the controller is affected by the non-linear load and failed in facing the generating harmonics during the operation. In case of the classical PI-controller, the system performance is improved but this improvement isn’t satisfactory for harmonics elimination. On the other hand, when the on-line particle swarm optimization is used, marked improvement occurs in the system behavior and its performance is enhanced. Third, SAPF is applied on the three-phase source voltages connected with fully controlled thyristor bridge rectifier which is connected with inductive-resistive. The PI-controller parameters are optimized by PSO. The results show that the system without the controller is affected by the generating harmonics during the operation. On the other hand, when the PSO is used, there is improvement in the performance of the system. from these, it is clearly understood that using the shunt active power filter under the PI-controller tuned by PSO gives good promotion for its use in the harmonics elimination of the non-linear electric grids. Fourth, SPAF is applied on the three-phase source voltages connected with fully controlled thyristor bridge rectifier which is connected with dynamic load (DC motor) and the PI-controller parameters are optimized by PSO. The motor is loaded by two different mechanical load torques, directly proportional to motor speed and the second proportional to square value of motor speed. The results show improvement in the behavior of the active filter to suppress the harmonic currents which is occurred by the dynamic non-linear loads in the non-linear system. Finally, this thesis discussed the traction load. The traction load is connected to the three-phase source voltages across the transmission lines. It is represented by RL-load across the rectifier diode bridge. This connection generates unbalanced system and also generates harmonics. SAPF is applied on this system to overcome the resulted problems from the traction load. It is controlled by the PI-controller which is tuned by PSO. Results show that the system without SAPF is affected (appearance of the harmonics in the source currents and the supply currents become unbalanced). But with SAPF the system performance is improved where the supply currents become balanced and the source current is approximately pure sine wave.