The authors are with the Advanced Control System Research Centre at "Dunarea de Jos" University of Galati in Romania. Their research interests are in the domain of static and dynamic optimizations, with a focus on dynamic system optimal control. The interest in the control of the wind energy conversion systems dates back to 1993. Iulian Munteanu received a B.Eng. degree in applied electronics from "Dunarea de Jos" University of Galati in Romania in 1996, a M.Sc. degree in instrumentation and control from Universite du Havre in France in 1997 and a Ph.D. degree in automatic control systems from "Dunarea de Jos" University of Galati in Romania in 2006, by defending a dissertation on the optimal control of wind power systems. From 1998 he is with the Department of Electronics and Telecommunications from "Dunarea de Jos" University of Galati in Romania. Between 2000 and 2005 he has had three doctoral stages at Laboratoire d'Electrotechnique de Grenoble in France, where he has worked on controlling the variable-speed asynchronous-machine-based wind power systems. He has authored and co-authored 1 book, 7 research reports, about 10 papers at international conferences and 5 papers in international journals. At the present he is a post-doctoral researcher at Grenoble Genie Electrique Laboratory in France. Antoneta Iuliana Bratcu received a M.Sc. degree in electrical engineering from "Dunarea de Jos University of Galati in Romania in 1996 and a doctoral degree in automatic control and computer science from Universite de Franche-Comte de Besancon in France in 2001. Her research interests include both discrete and continuous optimization. Between 2002 and 2005 she has had two post-doctoral stages respectively at Universite de Technologie de Troyes and Ecole Nationale Superieure des Mines de Saint Etienne in France. She has authored and co-authored 2 books, 3 research reports, more than 25 papers at international conferences and 9 papers in international journals. In 2007 she joined the Department of Electrical Energy Conversion Systems from "Dunarea de Jos" University of Galati in Romania, where she is an associate professor. She is presently working as a post-doctoral researcher at Grenoble Genie Electrique Laboratory in France. Nicolas-Antonio Cutululis received a M.Sc. degree in advanced automatic control and artificial intelligence and a Ph.D. degree in automatic control systems, both from "Dunarea de Jos" University of Galati in Romania in 1999 and 2005 respectively. His Ph.D. dissertation thesis concerns the design of control strategies for hybrid wind energy conversion systems. He has authored and co-authored 1 book, 5 research reports, 5 papers at international conferences and 7 papers in international journals. From 1999 he joined the Department of Electrical Energy Conversion Systems at "Dunarea de Jos University of Galati in Romania. At the present he is a scientist with the Wind Energy Department at Riso National Laboratory in Denmark. Emil Ceanga received a M.Sc. degree in electronics and a Ph.D. degree in automatic control systems, both from Bucharest Polytechnic Institute in Romania, in 1961 and 1969 respectively. Between 1993 and 2004 he has been five times visiting professor at Groupe de Recherche en Automatique et Electrotechnique at Universite du Havre in France and one time visiting professor at Universite du Quebec a Rimouski in Canada. In 2004 he received the distinction "Palmes Academiques" from the French Government. He has advised 15 Ph.D. dissertations and has authored and co-authored 15 books and more than 130 papers at international conferences and in international journals. Between 2001 and 2006 he was Director of the Advanced Control System Research Centre at "Dunarea de Jos University of Galati in Romania. He is presently a professor of electrical engineering at the Department of Electrical Energy Conversion Systems at the same university.