Impact of new requirements for DER onto protection functions and its testing procedures

The decreased number of power plants from DER (Distributed Energy Resource) in the past years was quite strong in Germany. In the same time, lots of thermal power plants have been shut down. Thus, power plants from DER have to take over functions for the stability of the grid that where unknown some years before. One of this new features is for example reactive power undervoltage protection or the request that the DER power plant does not disconnect during a fault in the connected grid (Fault Ride Through). All these features should be set correctly in such a way that the requested behavior is obtained. With powerful and standardized testing procedures, the requested behavior can be guaranteed. The article gives an overview about this new features and the corresponding testing methods. These testing methods can guarantee that the quality of test result is very high, independent of the testing person.