Systems, method, and computer readable medium are provided for a controller for a generator. The system includes a rectifier for converting a first AC signal generated by the generator to a first DC signal; a first DC-DC associated with energy storage and a first mode; a second DC-DC associated with an inverter and a second mode; a switch for alternately toggling between the first DC-DC and the second DC-DC, wherein the first mode prevents output to the electrical grid, and the second mode enables inversion of the second DC signal to a second AC signal via the inverter; and a processor that uses the indicator to operate the switch to operate the generator in the first mode when a connection to the grid does not conform with a parameter, and operate the generator in the second mode when the connection to the grid conforms with the parameter.

An electric generator for a wind turbine is provided including a stator or rotor, the stator or rotor having plurality of winding systems, each winding system covering a respective angular portion of the stator or rotor about an axis of rotation of the electric generator, and a controller for controlling the current flowing in the winding systems. The controller is configured for receiving or determining a thickness of an airgap between the stator and the rotor and controlling the current flowing in at least one of the winding systems so that a respective magnetic radial force is generated, the magnetic radial force acting on the stator and/or rotor for increasing the airgap where the airgap is below a threshold airgap value.

A DFIG wind power facility configured to be operated during grid faults is provided. The wind power facility includes a Doubly-Fed Induction Generator, a control system, an electric converter, a short-circuit controlled switch to selectively short-circuit the stator and a Stator Neutral Brake Chopper coupled to the stator. The DFIG includes a rotor and a stator, the stator including at least one three-phase winding. The electric converter includes a Machine Side Converter, a Grid Side Converter and a DC link connected therebetween. The SNBC includes a three-phase rectifier including three inputs, an impedance and an active high-frequency switch configured to vary the average value of the impedance by adjusting its duty cycle; each of the three inputs of the rectifier is connected to a phase of the at least one three-phase winding of the stator. Methods for operating a DFIG wind power facility during grid faults are also provided.