Modelling a wind turbine as a low-pass filter for wind to electrical power calculations

In this paper the filtering effect of a wind turbine is modelled to provide insight into the transient dynamics of a wind turbine generator (WTG), considering the fluctuating/turbulent nature of wind speed and the impact it has on fluctuating power feed-in to a power system. The results show that the turbine inertia of a WTG acts as a first-order low-pass filter, which suppresses the wind speed fluctuations with frequency content above 1.2 millihertz (mHz). Thus, less of the wind speed fluctuations propagates through as fluctuating power generation, which feeds into the rest of the power system. From the perspective of modelling the transients of a wind turbine's power generation, it is concluded that small (below 1 minute) resolution wind speed data is not required since the higher frequency components are filtered out.