Variable speed wind turbines capability for temporary over-production

New control systems for Variable Speed Wind Turbines (VSWT) need to be developed in order to provide inertia response and frequency control to support the grid. This work studies the behavior and capability of VSWT for providing temporary active power overproduction. The study is conducted on a multi-megawatt VSWT with Doubly-Fed Induction Generator. It was found that it is possible to have an active power overproduction of 0.2 pu for at least 10 seconds, which could be useful for the grid operator for restoring a critical situation of grid frequency dip. Nevertheless it is important to be aware about the underproduction power and the associated recovery period that follow a VSWT overproduction operation. The results can be used in designing suitable control systems for VSWT inertia response and frequency control.