System and method for reactive power control of a wind farm

A method for controlling an electrical power system, the electrical power system having a plurality of clusters of electrical power subsystems with a cluster transformer connecting each cluster of electrical power subsystems to a power grid, each of the electrical power subsystems having a power converter electrically coupled to a generator with a generator rotor and a generator stator, each of the electrical power subsystems defining a stator power path and a converter power path for providing power to the power grid, the converter power path containing a two-winding power transformer, the method comprising:

• receiving, via a plurality of cluster-level controllers, a reactive power command from a system-level controller;
• generating, via the plurality of cluster-level controllers, a cluster-level reactive current command for each cluster of electrical power subsystems based on the reactive power command;
• and,
• distributing, via the cluster-level controllers, a subsystem-level reactive current command to subsystem-level controllers of the electrical power subsystems based on the cluster-level reactive current command.

A wind farm, comprising:

• a plurality of wind turbine clusters each comprising a plurality of wind turbines, each of the wind turbines having a power converter electrically coupled to a generator with a generator rotor and a generator stator, each of the wind turbines defining a stator power path and a converter power path for providing power to the power grid, the converter power path containing a partial power transformer;
• a cluster transformer connecting each cluster of wind turbines to a power grid;
• and,
• a plurality of cluster-level controllers, each of the cluster-level controllers communicatively coupled to one of the wind turbine clusters, the cluster-level controllers configured to perform one or more operations, the one or more operations comprising:
• receiving a reactive power command from a farm-level controller;
• generating a cluster-level reactive current command for each cluster of wind turbines based on the reactive power command;
• and,
• distributing a turbine-level reactive current command to turbine-level controllers of the wind turbines based on the cluster-level reactive current command.