Because of the increasing energy demanding in the world, the people began to search for the new energy sources. Renewable energy sources are the most emphasized one to obviate this energy demanding. The energy production from the wind is one the most important renewable energy sources. The wind turbine technology develops rapidly. By the reasons like the instability of the wind force, changes in wind speed, variations in load demands, and the use of nonlinear load types, the power transmitted from wind turbine to the load get affected very much besides the voltages oscillations at various busses along the transmission and distribution power lines. Due to the ability of induction generators generating the same power at different speeds by using proper controllers, these types of generators are preferred in wind power systems in order to reduce the effects of the wind speed changes on the power transferred. However, the induction generator itself is not sufficient to eliminate or reduce the power, frequency and voltage oscillations and the harmonics caused by the switched type loads and converters. In this thesis, a Dynamic Voltage Regulator/Switched Power Filter (DVR/SPF) is proposed to overcome both power quality and voltage stability problems described above. Beside the DVR/SPF a novel dynamic three loop error driven control structure is also proposed to be used in the filter control process. The total dynamic error signal is then minimized by using a modified fuzzy logic controller (MFLC) to meet the criteria’s required for high power quality, stable frequency and voltage levels. The performance of the MFLC is verified by comparing the results obtained using classical proportional plus integral (PI) controller. The proposed DVR/SPF, dynamic three error driven loops, PI and MFLC are modeled and simulated in MATLAB/SIMULINK Simpower environment. The simulation results are evaluated for the performance verification of the proposed filter and controllers.
Key Words: Wind Energy, Power Quality, Fuzzy Logic Controller, Dynamic Voltage Regulator, Switched Power Filter, Tri Loop Driven Error Signal Generator.