A new model for output power calculation of variable-speed wind turbine systems

The evolution of power semiconductors has contributed enormously to variable-speed wind turbine systems (WTS). In this study, a new method for power output calculation of variable-speed WTSs is proposed. The model is developed from the charging voltage equation of capacitors and is only a function of the rated power and the rated wind speed. It is validated on the manufacturer power curve of different type and size of variable-speed WTSs. Additionally, by using developed model, the capacity factor of this type of WTS is also modelled in terms of the rated wind speed and Weibull distribution of the wind site. Parametrical analyses have been carried out to show the effect of rated wind speed on the value of turbine capacity factor, resulting of energy production for different wind conditions (Weibull scale parameter). The feasible value of rated wind speed for located or considered variable-speed WTSs at different stations in Turkey are also analysed and results are given.