“…A significant amount of scientific research has been conducted on the control of wind turbine systems, especially utilising sliding-mode control (Beltran, AhmedAli, and Hachemi Benbouzid 2008), proportional-integralderivative (PID) (Abdin and Xu 2000;Maureen and Balas 2002), fuzzy-adaptive control (Galdi, Piccolo, and Siano 2008), non-linear robust control (Iyasere, Salah, Dawson, and Wagner 2008) and even wind-model-based predictive control (Senjyu et al 2006). In Beltran et al (2008), authors proposed a control strategy that is based on a sliding-mode controller to maximise the power efficiency where the turbine tip speed ratio must be maintained at its optimum value despite wind variations.…”