Pitch control of small H-type Darrieus vertical axis wind turbines using advanced gain scheduling techniques

• Published in: Renewable energy 2020-12, Vol.161, p.756-765
• Main Authors: Bundi, Josephat Machoka, Ban, Xiaojun, Wekesa, David Wafula, Ding, Shuchen
• Format: Article
• Language: English
• Subjects: Gain-scheduling; Linear matrix inequalities; Pitch control; VAWT
• ISSN: 0960-1481; 1879-0682
• DOI: 10.1016/j.renene.2020.05.184

During sudden wind speed changes, the response time of the wind turbine rotor is essential so that optimum operating condition always governs. As a result, wind turbine rotors especially the blades are the most delicate parts in a fluctuating wind condition posing a challenge for their effective operation. This paper focuses on gain scheduling pitch and MPPT control for a small H-type Darrieus vertical axis wind turbine (VAWT) with respect to the power output. A gain scheduled controller is designed by solving Linear matrix inequalities (LMIs) and used for stability control of the Darrieus VAWT rotor in an urban wind condition. A NACA 0018 airfoil is used to demonstrate the wind speed variations and nonlinear aerodynamic rotor behavior. The Stochastic Differential Equations (SDEs) as a function of a random number are imposed in Simulink using MATLAB R2018b. The proposed gain scheduled controller is found to be stable and achieves better performance under a gusty and turbulent wind condition compared to conventional controllers. The simulations are consistent to published experimental and numerical findings such that the system behaves as closely as possible to the real H-Darrieus turbine. •Pitch angle control increases efficiency of a small vertical axis wind turbines.•Gain scheduling guarantees desirable performance for small scale vertical axis wind turbines.•Gain scheduling control provides better quick response to wind gusts.•Pitch angle control is limited by its nonlinear relationship with the power coefficient.