Hindawi Publishing Corporation Conference Papers in Engineering Volume 2013, Article ID 125801, 9 pages http://dx.doi.org/10.1155/2013/125801 Conference Paper Performance of Control Dynamics of Wind Turbine Based on Doubly Fed Induction Generator under Different Modes of Speed Operation A. A. Mohammed Electrical and Electronic Engineering Department, University of Benghazi, Elmarj, Libya Correspondence should be addressed to A. A. Mohammed; n anis2007@yahoo.com Received 14 February 2013; Accepted 9 May 2013 Academic Editors: M. Elmusrati, A. Gaouda, and H. Koivo his Conference Paper is based on a presentation given by A. A. Mohammed at “International Conference on Electrical and Computer Engineering” held from 26 March 2013 to 28 March 2013 in Benghazi, Libya. Copyright © 2013 A. A. Mohammed. his is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. here are many solar power and wind stations installed in the power system for environmental and economic reasons. In fact, wind energy is inexpensive and the safest among all sources of renewable energy, it has been recognized that variable speed wind turbine based on the doubly fed induction generator is the most efective with less cost and high power yield. herefore, this paper has chosen doubly fed induction generator for a comprehensive study of modeling, analyzing, and control. DFIG in wind turbine has to operate below and above the synchronous speed, which requires smooth transition mode change for reliable operation, specially, close to synchronous speed where the DFIGWT instability starts to appear. Furthermore, its output electric power has to be controlled to provide stability for the power system; hence its performance depends on the generator itself and the converter operation and control system. his paper presents completed mathematical model of DFIG with its AC/DC/AC converter driven by DC machine. A new vector control technique is designed and modeled, which allows to evaluate the dynamic performance of the controller under (below, above, and through synchronous speed). he simulation results demonstrate the accuracy and high performance of the new control system of DFIG for wind turbine, which provides smooth transition mode without using any extra circuit. 1. Introduction he electric power generation using wind farms is subject to considerable attention in the world due to the increase of electricity demand and consumption, which led to the depletion of existing energy sources such as fossil fuels, coal, and oil. Furthermore, there are many countries unable to generate hydroelectric power or nuclear energy. Indeed, wind power is environmentally and economically acceptable and the safest source among renewable energy sources [1]. Large wind turbines can be operated at a constant speed or variable speed using diferent types of generators that can be either directly connected to the network or connected through a power electronic converter. In recent years more development has been carried out to improve the performance of variable speed wind turbines to overcome the problem of the necessity to operate above, below, and through synchronous speed; as the result of this development the wind energy industry ended up with doubly-fed induction generator wind turbine (DFIGWT), which is the most eicient generator in wind energy con- version system so far. In fact, DFIG it is one of the most important generators in high-power applications; it is a form of three-phase asynchronous machine with its rotor windings also connected to the grid through the power electronic converter [2]. Indeed, DFIG ofers a number of features when it is compared with other generators: its ability to operate at (∓30%) of synchronous speed, its converter has only to handle rotor circuit power, high eiciency, maximum power extracted, and independent control of active and reactive powers. On other hand, DFIG has some disadvantages such as its sensitivity to unbalanced fault condition which can