Indirect effects of turbulence frequency on maximum power point tracking of wind turbine

摘要

Due to the randomness and rapid fluctuation of turbulent wind, the effects of turbulence on maximum power point tracking (MPPT) of wind turbine should be focused on. Previous work was mainly concerned with two characteristics of turbulent wind, i.e. mean wind speed and turbulence intensity. It has been found that besides the aforementioned two factors, turbulence frequency is also included in the characteristics of turbulent wind. Confronting this characteristic of wind speed fluctuation which has not been fully considered, relevant researches merely analyzed the impact of the variation of turbulence frequency itself on MPPT. However, the variation of the extent of mean wind speed and turbulence intensity affecting MPPT resulted from different turbulence frequency, i.e. the indirect effect, is required to be further investigated. For this purpose, the relationship between wind speed frequency and the sensitivities of MPPT efficiency to mean wind speed and turbulence intensity are derived in this paper. Moreover, the mechanism of the indirect effects of wind speed frequency on MPPT is investigated by the time-domain simulations on the simplified model of wind turbine with periodic wind speed and the FAST model of NREL CART3 wind turbine with turbulence.