Fault ride through performance of wind energy converters with FACTS capabilities in response to up-to-date German grid connection requirements

Wind Farms (WFs) that are nowadays connected to the German distribution or transmission system have to fulfill the technical requirements stated in the 2009 revision of the German Renewable Energy Sources Act. On the one hand these requirements specify more precisely the already existing connection conditions they are based on. On the other hand they give additional criteria especially regarding the dynamic behavior during under and over voltage conditions in the grid. ENERCON Wind Energy Converters (WECs) can fulfill these stringent demands due to their full-size converter design and the associated so-called FACTS Capabilities. Consequently, ENERCON was awarded the first type-certificate according to these German connection conditions in 2009. The present paper describes the Fault Ride Through (FRT) performance of ENERCON WECs that responds specifically to the above mentioned requirements. Furthermore, measurement examples that prove compliance with the connection conditions are shown and it is explained how the corresponding field tests are done.