Control and emulation of small wind turbines using torque estimators

Soft-stall control of small wind turbines is a method to protect the generation system or the load from high wind speeds while keeping the system generating. Soft-stall activation must be due to an excess of power or torque/current. This paper proposes a method to improve the existing soft-stall methods for over torque/current protection by the development of a turbine torque estimator. Due to the inconvenience of the continuously changing weather conditions, wind turbine emulators are broadly used by researchers instead of actual wind turbines. This paper also proposes two methods to emulate the wind turbine inertia without communications between the load drive (wind turbine emulator) and the generation system controller.