Mamo, Mengesha (PhD)Tadesse, Teshale2018-06-292023-11-282018-06-292023-11-282016-06http://etd.aau.edu.et/handle/12345678/4837Wind power is growing rapidly around the world as a means of dealing with the world energy shortage and associated environmental problems. A wind electrical generation system is the most cost effective of all the environmentally clean and safe renewable energy sources in world. In this thesis, double fed induction generator and grid system are modeled under normal conditions of the grid system and under grid faulty conditions. Any abnormalities associates with grid are going to affect the system performance. Taking this into account, the performance of double fed induction generator (DFIG) variable speed wind turbine under network faults is studied using simulation developed in MATLAB/SIMULINK results show the fault behavior of the double fed induction generator when a sudden short circuit and voltage dip on the grid side. After the clearance the short circuit fault and voltage dip the proportional integral controller manages to restore the wind turbine‘s normal operation. The three-phase fault model is done by giving a fault equivalent resistance value of 0.01Ω and voltage dip at grid side with the value of 0.45p.u. At this time, the current, voltage, active power and reactive power value of DFIG is fluctuating between 0.2p.u and 1.36p.u, 0.7p.u and 1.12p.u, 0 and 6MW, 0.75 and 0.42MVAr, respectively. But in order to operate at normal operation the DFIG current and voltage value is at 1p.u. The maximum active power that generated from DFIG is 9MW. To stabilize the system the proportional integral controller compare the reference voltage and current with generated and minimize the error between voltage and current. The proportional integral controller minimizes the error by decreasing the rising time and makes the value of current and voltage to 1p.u. The detailed results of steady state and faulty or three-phase short circuit on grid system has been noted and analyzed with proper justification. In order to increase the fault ride through capabilities of the system, crowbar protection and series dynamic resistor could be added to the system. This thesis done by modeling and simulating of the controller using Matlab/Simulink in wind turbine system integrated with grid system. Finally, we observed and interpreted the result with Matlab/Simulink simulation software. Keywords:- , doubly fed induction generator; wind turbine; proportional integral controller; MATLAB/SIMULINK;endoubly fed induction generator; wind turbine; proportional integral controller;MATLAB/SIMULINK;Thesis