Control of active power reserve in a wind-farm

A system of active power reserve regulation in a wind farm having a plurality of wind turbines, comprising:

• a first subset of the plurality of wind turbines operating at a maximum available power output;
• a second subset of the plurality of wind turbines operating in accord with active power limitation commands;
• a wind-farm controller which interacts with the plurality of wind turbines to manage a reserve of active power using the active power limitation commands and which estimates a maximum amount of available active power generated by the plurality of wind turbines based on the first subset of the plurality of wind turbines;
• an active power wind-turbine controller in each of the plurality of wind-turbines, wherein each active power wind turbine controller is configured to limit a maximum amount of available active power generated by a corresponding one of the plurality of wind turbines according to the active power limitation commands received from the wind-farm controller for managing the reserve of active power.