System-Wide Evaluation of Inertia Support Potentials from Wind Farms

Abstract

In order to limit anthropogenic climate change as well as the dependency on fossil fuels, the wind power generation is rising world wide. Since modern wind turbines are usually variable speed wind turbines, which are connected to the grid via a converter, this causes a decrease in grid coupled inertia. Because decreased inertia causes faster and greater frequency changes for the same disturbances, it is discussed widely how variable speed wind turbines can contribute inertia to the power system. In this project report, inertial response from wind turbines at the system level is investigated with a focus on the swedish power system. An existing database of wind turbines and a metereological model containing wind speeds on defined grid points are used to determine the operating points of all wind turbines included in the database for each hour in the investigated time span 2010 to 2015. Furthermore, the performance of these turbines in three different fixed trajectory inertial response approaches is simulated, aggregated to the system level and analysed accordingly. In this work it is shown that a reliable amount of inertial support in relation to their production can be expected from wind turbines. Although the number of online wind turbines and the total energy production from wind turbines are not strongly correlate, it could been proven that for the fixed power and time inertial response approach a linear relation between the aggregated inertial response capability and total energy production exists. The support power from wind turbines amounts under this conditions to 1:13 times their steady state power. It could further been shown that the assumed inertial response strategies would allow for the compensation of a dimensioning fault.