Patent ID: 11894681
Assignee: GENERAL ELECTRIC COMPANY
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  G  Y | IPC G  H

Claim 19:
20. A system for controlling a wind farm to dampen power system oscillations on an electrical grid; the wind farm having a plurality of wind turbines electrically connected to the electrical grid at a point of interconnection (POI); the system comprising:
a generator and associated wind turbine controller configured with each of the wind turbines;
a farm-level controller communicatively coupled to each of the wind turbine controllers, the farm-level controller comprising a processor for implement a plurality of first operations;
the plurality of first operations comprising:
receiving one or more grid signals having a characteristic indicative of a power system oscillation;
generating an auxiliary signal from the grid signals;
using the auxiliary signal to modify a reactive power command transmitted to the wind turbine controllers to modulate reactive power output from the wind turbine generator to change a voltage at the POI, the voltage change damping the power system oscillations;
wherein the generating of the auxiliary signal at the farm-level controller further comprises the farm-level controller receiving capability limits at operating conditions of each of the inverter-based generators and adjusting the auxiliary signal to limit a change in reactive power (ΔQ) utilized for damping, wherein the limit is calculated and implemented at the plant level as a percentage of the reactive power capability of the plant or inverter-based generators; and
further comprising utilizing a switchable washout filter having at least two washout filters with different time constants upstream of a (ΔQ) limiter, wherein when the (ΔQ) limit is reached, output from the switchable washout filter is changed to the washout filter having a lower time constant.