Eesmärk
An offshore wind power plant is going to be connected to the Danish 150 kV grid, by the end of 2019. A harmonic study was conducted as part of the project to verify that the power quality of the new substations will meet Energinet quality criteria. This study found that the level of harmonics in Engbjerg will be above the Energinet limits. Hence it was decided that a harmonic filter must be installed for mitigation. Using EMT simulations, a 65 Mvar C-type filter tuned for the 5th harmonic (250 Hz), with a quality factor of 2, has been shown to reduce the overvoltages to acceptable levels.