Modern Applied Science; Vol. 10, No. 8; 2016 ISSN 1913-1844 E-ISSN 1913-1852 Published by Canadian Center of Science and Education 1 Simulation and Control of Doubly Fed Induction Generator (DFIG) Used in Wind Turbines by Using Genetic Algorithm Faraz Chamani 1 & Mohammad Satkin 2 1 Department of Electrical Engineering, Islamic Azad University, Sari Branch, Iran 2 Faculty of Environment and Energy, Science and Research Branch, Islamic Azad University, Tehran, Iran Correspondence: Faraz Chamani, Islamic Azad University, Iran. E-mail: chamani.faraz@yahoo.com/tsatkin@yahoo.com Received: March 8, 2016 Accepted: April 1, 2016 Online Published: April 26, 2016 doi:10.5539/mas.v10n8p1 URL: http://dx.doi.org/10.5539/mas.v10n8p1 Abstract Wind energy is one of the extraordinary sources of renewable energy due to its clean character and free availability. With increase in wind power penetration, the wind farms are directly influencing the power systems. The majority of wind farms are using variable speed wind turbines equipped with doubly fed induction generators (DFIG) due to their advantages over other wind turbine generators (WTGs). Therefore, the analysis of wind power dynamics with the DFIG wind turbines has become a very important research issue, especially during transient faults. In this article, a controller is provided to control the active and reactive power of a wind system equipped with doubly fed induction generator. The generator is connected to the grid by a back to back converter that gets benefit from control system known as single periodic controller. Grid and generator side converters respectively control the generator speed and reactive power using proposed controller. In order to increase the accuracy of controller, we optimized its PI parameters using genetic optimization algorithm. Finally, simulation results conducted by the MATLAB software are shown. The results of simulation gained through this system, show the capability of proposed controller under error conditions for controlling active and reactive power and also elimination of harmonics caused by non-linear load. Keywords: doubly fed induced generator, control system, PI parameters, genetic algorithms 1. Introduction Due to the diversity of human needs in relation to energy and inability of direct use of many primary energy resources, humankind would change and transform these energies to desired type of energy such as electric energy. Electric energy is produced mainly by fossil fuels. The fossil fuels in addition to their limited life, are associated with environmental problems. Hence, use of renewable sources such as wind has been proposed. (Moghadas Tafreshi, 2011).Increase in use of renewable energy is due to their compatibility with environment, availability and low costs. (Gautam, Vittal, Harbour, 2009) The use of wind energy in many countries is growing. In current situation regarding the economic feasibility of wind energy compared with other resources of new energies, getting benefit from wind energy is widespread and Iran is not an exception. After rising oil prices in 1973, advanced industrial countries were forced to consider energy problems more seriously, and this was the beginning of long-term programs in the field of energy saving and optimization. In other words, the use of renewable energy sources, especially wind energy, was the agenda of these countries. One of the main problems that should be considered in use of wind turbines, is their control. In general, control of wind turbines is two main axis, which includes: 1. The maximum absorbable wind mechanical power from wind turbine for different values of wind speed would be different. So the maximum absorbable wind mechanical power at every moment should be determined. 2. Turbine generator should be controlled so that can track and produce the maximum mentioned power at any moment. Wind turbine systems equipped with double-fed induction generator have the following advantages: As a result of constant frequency of network and adjusting the electric frequency of rotor, control of mechanical speed and absorbance of maximum power of the wind turbine is possible. Hereby, depreciation of mechanical devices is reduced.