Parameter Optimization in the Design of a Grid-side Converter Controller in the Light of Grid Faults

Parameter Optimization in the Design of a Grid-side Converter Controller in the Light of Grid faults is presented. The primary aim is to provide for a fault-ride-through (FRT) capability of Wind Turbine with Doubly Fed Induction Generator in the Light of new grid codes. New grid codes require that the wind turbines remain continuously on-line and supply the grid during voltage sags. An active damping criterion that has the capacity to inhibit the abnormal rise of the DC-link current and voltage, stator currents and hence rotor currents during voltage sag is implemented. This is achieved by introducing an optimum active resistance (performing the damping) in the minor feed-back loop of the grid-side converter current controller. Against the abnormal rise in the DC-link voltage capable of exciting the switching of a protective system, a constant DC-link voltage of almost 80 per cent of the nominal value is achieved. Also, against the increase to about twice its nominal value, the nominal magnitude of the rotor current is maintained throughout the duration of the fault.