Quantifying the Effect of Wind Turbine Size and Technology on Wind Power Variability

Quantifying wind power variability can be essential to both power system planners and operators, as well as wind farm owners and investors. In this paper the conditional range metric, a novel probabilistic variability metric, is used to quantify wind power variability. The comparison of the wind power variability from four turbines of the same size but different technologies (fixed speed, variable slip, DFIG, full converter) yields that the full converter wind turbine has the least variable and the fixed speed the most variable output, with the fixed speed being 15% more variable than the full converter turbine output. Comparing the output from two variable speed wind turbines of different sizes suggests that wind power variability decreases slightly with turbine size in p.u. values. However, the results of comparing the wind power variability from one turbine at one site to the wind power variability from the aggregated output of two identical turbines at different sites indicate that wind power aggregation provides a significant reduction in wind power variability, since variability increases by no more than 75% regardless of wind turbine size and technology.