Abstract: A control method for the rotor side converter of a doubly-fed induction generator in a wind turbine for disturbances in the electric grid is provided. A control system includes a calculating unit configured for calculating at least one reference current. A current controller which is a hybrid controller configured to operate in two different modes, a first operating mode, set during a transient of a disturbance in an electric grid, where the current controller is configured to operate with a modulation index being outside a linear area and a second operating mode, set during a stable state of the disturbance in the electric grid, where the current controller is configured to operate with a modulation index inside the linear area, thereby instantly providing a maximum voltage available in a rotor so as to satisfy the at least one reference current.

Abstract: The invention provides methods and systems for real-time monitoring of the insulation state of wind-powered generator windings comprising the following steps: a) capturing in real-time, during a predetermined time period (in situations where the generator is synchronized to the electrical network but is not yet couplet thereto as well as in situations where the generator is producing energy) the values of one or more electrical and vibration variables of the generator; b) obtaining in real-time, the temporal evolution of the vibration and of the inverse components of electrical variables at one or more predetermined frequencies; c) identifying a possible generator insulation fault when the inverse component of at least one electrical variable and/or one vibration at a predetermined frequency exceeds an absolute threshold or a temporal increase threshold pre-sets.

Abstract: The invention provides methods and systems for real-time monitoring of the insulation state of wind-powered generator windings comprising the following steps: a) capturing in real-time, during a predetermined time period (in situations where the generator is synchronized to the electrical network but is not yet couplet thereto as well as in situations where the generator is producing energy) the values of one or more electrical and vibration variables of the generator; b) obtaining in real-time, the temporal evolution of the vibration and of the inverse components of electrical variables at one or more predetermined frequencies; c) identifying a possible generator insulation fault when the inverse component of at least one electrical variable and/or one vibration at a predetermined frequency exceeds an absolute threshold or a temporal increase threshold pre-sets.