Estimation of annual energy delivered by a variable speed wind generating system using historical wind data

This paper describes various approaches of estimating the annual energy delivered by a large size variable speed wind generating system using historical wind speed data. First a discrete wind speed histogram is produced from historical wind data. The wind histogram and the turbine power characteristic supplied by the manufacturer are then used to estimate the annual energy delivered by the turbine. The wind characteristic is also modelled by Rayleigh statistics using the average wind speed data and combined with the turbine power characteristic to obtain the annual energy delivered by the turbine. The dynamic model of the wind turbine and the associated doubly-fed induction generator given in the SimPowerSystems blockset is used to determine the generator output power for various wind speeds. The generator power and the discrete wind speed histogram are also used to obtain the annual energy supplied by the generator. The results obtained by the above approaches are also carefully analysed and compared. The reasons for slight discrepancies of the results are also discussed.