US 11,990,755 B2
Method for detecting power oscillation in an electric power grid
Per Hagen Nielsen, Tilst (DK); Lennart Petersen, Aarhus (DK); and Germán Claudio Tarnowski, Aarhus (DK)
Assigned to VESTAS WIND SYSTEMS A/S, Aarhus (DK)
Filed by VESTAS WIND SYSTEMS A/S, Aarhus (DK)
Filed on Apr. 21, 2023, as Appl. No. 18/305,055.
Claims priority of application No. PA 2022 70209 (DK), filed on Apr. 21, 2022.
Prior Publication US 2023/0344231 A1, Oct. 26, 2023
Int. Cl. H02J 3/24 (2006.01); G01R 19/04 (2006.01); G01R 19/10 (2006.01)
CPC H02J 3/241 (2020.01) [G01R 19/04 (2013.01); G01R 19/10 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A method for detecting power oscillation in an electric power grid, wherein the method comprises:
integrating a filtered signal on a first interval, the filtered signal being associated with the electric power grid;
based on the integration of the filtered signal on the first interval, determining a positive half-period area of the filtered signal and a negative half-period area of the filtered signal, one of the positive half-period area and negative half-period area being immediately subsequent to the other one of the positive half-period area and negative half-period area; and
determining that a power oscillation in the electric power grid is detected when the following two conditions are met:
a sum of the positive half-period area of the filtered signal and the negative half-period area of the filtered signal is below a first threshold; and
the absolute value of one of the positive half-period area and negative half-period area is above a second threshold.