Towards robust controller design using \(\mu \)-synthesis approach for speed regulation of an uncertain wind turbine

  • N. V. A. RavikumarEmail author
  • G. Saraswathi
Original Paper


Wind turbines are subjected to factors like fatigue, aerodynamics, structural flexibility and wind turbulence which lead to uncertain behaviour. This affects stability and deteriorates the performance of the large structured wind turbine. In order to reduce the effects of uncertainties on the system performance and its structure, a robust controller design is necessary. In this paper, it is proposed to design a \(\mu \)-synthesis-based robust controller to overcome the effects due to uncertainties. A \(\pm \,25\%\) variation in the values of the system matrix elements is considered for analysis in this paper. A 109th order of the proposed \(\mu \)-controller is obtained, wherein it is reduced to a 7th order controller by using the balanced truncation method. The robust stability and robust performances are satisfactorily achieved with both these controllers. Furthermore, the worst-case performance of the uncertain wind turbine is also analysed.


Robust \(\mu \)-controller Robust stability Robust performance Uncertainty Wind turbine Model order reduction 



The authors express their sincere gratitude to Professor Bharani Chandra Kumar Pakki, Head of the Department of Electrical and Electronics Engineering, GMR Institute of Technology, Rajam, Andhra Pradesh, India.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Electrical and Electronics EngineeringJNTUKKakinadaIndia
  2. 2.Department of Power EngineeringGMR Institute of TechnologyRajam, SrikakulamIndia
  3. 3.Department of Electrical and Electronics EngineeringJNTUK – University College of EngineeringVizianagaram, DwarapudiIndia

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