National Grid ESO published their interim report for the disturbance which occurred on August 9th 2019. The event caused the disconnection of approx. 5% of end consumers and resulted in long interruption in railway services. National Grid’s incident analysis identified that the initial event was a lightning strike into the overhead line between Eaton Socon and Wymodley, leading to a single-phase-to-ground fault which was cleared properly by the protection system.
However, the fault resulted in the disconnection of the close-by Combined-Cycle Gas Turbine plant in Little Barford and, even more surprisingly, in the drastic reduction in power output of the offshore wind farm Hornsea One. As National Grid mentions “the initial reaction from Hornsea’s systems was as expected in attempting to accommodate and address the system condition, but very shortly afterwards as the reaction expanded throughout the plant, the protective safety systems activated”.
A project spokesman mentioned “the relevant part of the system has been reconfigured and […] should this extremely rare situation arise again, Hornsea One would respond as required”.
Read the full article here.