METHOD FOR GRID IMPEDANCE AND DYNAMICS ESTIMATION

Estimating components of a grid impedance, Z, of a power grid being coupled to a power generating unit at a point of interconnection is disclosed. A voltage, Vmeas, across the point of interconnection; an active current, IP, and/or an active power, P, delivered by the power generating unit to the power grid; and a reactive current, IQ, and/or a reactive power, Q, delivered by the power generating unit are determined. A parameter estimation vector is estimated using a recursive adaptive filter algorithm, and on the basis of Vmeas, IP, P, IQ and/or Q. A model representation of the power grid is created on the basis of the parameter estimation vector, and a system DC gain vector for the power grid is calculated, using the model representation. Finally, Z, and/or a resistance, R, of Z, and/or a reactance, X, of Z, is derived from the system DC gain vector.