Open AccessA novel nonlinear observer‐based LQ control system design for wind energy conversion systems with single measurement
Author(s) -
Vu VanPhong,
Do Ton Duc
Publication year - 2019
Publication title -
wind energy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.743
H-Index - 92
eISSN - 1099-1824
pISSN - 1095-4244
DOI - 10.1002/we.2345
Subject(s) - control theory (sociology) , observer (physics) , aerodynamics , nonlinear system , trajectory , rotor (electric) , polynomial , induction generator , computer science , torque , generator (circuit theory) , wind power , mathematics , power (physics) , control (management) , engineering , physics , electrical engineering , quantum mechanics , artificial intelligence , mechanical engineering , mathematical analysis , astronomy , thermodynamics , aerospace engineering
The issue of tracking the optimal power for wind energy conversion systems (WECSs) via regulating the rotor speed of the generator is taken into account in this study. Additionally, a novel polynomial observer is proposed for estimating not only aerodynamic torque in WECSs but also d ‐axis and electromagnetic torque. Therefore, in this new approach, only the rotor speed of the generator is required to be measured instead of measuring all state variables. With the new observer form, the aerodynamic torque does not need to satisfy any constraints, which are mandatory in the previous methods. It should be noted that this methodology has not been investigated for the WECSs in any previous papers. To design a complete control system, a linear optimal control method cooperated with the polynomial observer is employed to track the optimal trajectory of a generator. Moreover, in this paper, the permanent magnet synchronous generator is used. In addition, on the basis of the Lyapunov theory and sum‐of‐square (SOS) technique, the conditions for observer synthesis are derived in the main theorems. Finally, the simulation results are provided to prove the effectiveness and merit of the proposed method.