Fault ride-through behavior of MV-connected wind turbines and CHP-plants during transmission grid disturbances

Apart from the positive technical consequences, the increasing penetration of Distributed Generation (DG) units connected to the distribution network brings new requirements in the protection strategy. Grid disturbances at the transmission level can cause the unwanted disconnection of large amount of DG, leading to undesired power imbalances. This paper examines how transmission network faults can affect the operation of DG units connected on to the distribution network, and how current under-voltage protection settings cope with these fault cases.