Nonlinear Optimal Control for PMSG-Based Wind Energy Conversion Systems



wind energy conversion system, permanent magnet synchronous generator, nonlinear control, optimal control, maximum power point tracking


This paper presents the design of a nonlinear optimal control strategy for a wind energy generation system based on a small scale wind turbine, a permanent magnet synchronous generator, a back-to-back power converter, and an LCL filter interconnected with the grid. The main control objectives in this energy system involve the trajectory tracking and regulation of different system variables as generator angular speed, DC-link voltage and reactive power. In order to fulfill these objectives, the application of optimal controllers based on the state-dependent coefficient factorization technique is proposed for both the generator-side converter and the grid-side converter. The advantages of the proposed control scheme are to achieve a wide system operating range, due to the controller design takes into account the system nonlinearities, and in addition, an efficient trajectory tracking of time-varying references generated by a maximum power point tracking algorithm, which uses a wind speed estimator. Also, an LCL filter is used to attenuate the harmonic content of the injected current to the utility grid to satisfy interconnection standards, which requires a THD below 5%. The effectiveness of the proposed controllers is verified via simulations developed in Matlab/Simulink, where the variables to be controlled reach the desired references that ensure proper operation, maximum power extraction, and fulfillment of interconnection standards.


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Author Biographies

David Cortes-Vega, Universidad Michoacana de San Nicolas de Hidalgo

David Cortes-Vega received the B. Sc. and M.Sc. degree in electrical engineering from the Universidad Michoacana de San Nicolas de Hidalgo (UMSNH), Morelia, Mexico in 2013 and 2016, respectively. Currently, he is working on his D.Sc. in electrical engineering at the UMSNH. His research interests are nonlinear control, robust control, applied control, and renewable energy systems.

Fernando Ornelas-Tellez, Universidad Michoacana de San Nicol´as de Hidalgo

Fernando Ornelas-Tellez received the B.Sc. degree from the Instituto Tecnologico de Morelia (ITM), Morelia, Mexico, in 2005 and the M.Sc. and D.Sc. degrees in electrical engineering from the Advanced Studies and Research Center, National Polytechnic Institute (CINVESTAV-IPN), Guadalajara, Mexico, in 2008 and 2011, respectively. His research interest centers on neural control, direct and inverse optimal control, passivity and their applications to robots, electrical machines, and power electronics.

Juan Anzurez-Marin, Universidad Michoacana de San Nicol´as de Hidalgo

in Electrical Engineering from the Universidad Michoacana de San Nicolas de Hidalgo (UMSNH), Mexico, in 1991; the M.Sc. degree in Electronic Engineering from the Instituto Tecnologico de Chihuahua, Mexico, in 1997 and D.Sc. degree in Electrical Engineering at the CINVESTAV-Guadalajara Campus, Mexico, in 2007. His research interests include Instrumentation and Control Systems, Fault Diagnosis Algorithms Design for Nonlinear Systems and Energy Harvesting Applications.


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How to Cite

Cortes-Vega, D., Ornelas-Tellez, F., & Anzurez-Marin, J. (2021). Nonlinear Optimal Control for PMSG-Based Wind Energy Conversion Systems. IEEE Latin America Transactions, 19(7), 1191–1198. Retrieved from