Abstract: A utility grid is provided, the utility grid including a centralized controller; an intermittent renewable energy source for generating electrical power; at least one further power generation system; and a local controller for controlling the total power output of the intermittent renewable energy source and the at least one further power generation system, wherein the centralized controller is connected with the local controller and adapted to request a desired total power output from the local controller.

Abstract: The invention relates to a method for inputting power into a multiphase alternating current grid by means of a transformer (18) which is electrically interconnected between the alternating current grid and a number of input phases (91, 92, (p3) corresponding to the number of grid phases (O1, 02, 03) of the grid, wherein at least one voltage characteristic (Ueffl, Uef˜2, Ueff3) of one of the grid phases (O1, 02, 03) is determined, and an input of reactive currents occurs as a function of a previously determined deviation (AU1, AU2, AU3) of the voltage characteristic (Ueffl, Ueff2, Ueff3) of the at least one grid phase (O1, 02, 03) relative to a corresponding target voltage characteristic (Usoll).

Abstract: The invention relates to a method for inputting power into a multiphase alternating current grid by means of a transformer which is electrically interconnected between the alternating current grid and a number of input phases corresponding to the number of grid phases of the grid, wherein at least one voltage characteristic of one of the grid phases is determined, and an input of reactive currents occurs as a function of a previously determined deviation of the voltage characteristic of the at least one grid phase relative to a corresponding target voltage characteristic. It is provided that the deviation of each one of the voltage characteristics is determined, and the input of the reactive currents in case of deviations that are asymmetrical with respect to the symmetry of the target voltage characteristics is an asymmetrical input of the reactive current with respect to the respective input at the input phases.

Abstract: A wind turbine generator includes at least one rotating member, at least one stationary member, and a clearance gap control system. The stationary member is positioned such that a clearance gap is defined between a portion of the rotating member and a portion of the stationary member. The clearance gap is configured to facilitate transmitting a controllable magnetic flux therethrough. The control system includes at least one clearance gap measurement assembly, at least one power converter, and at least one controller. The controller is coupled in electronic data communication with the assembly and the converter and is configured to modulate a dimension of the gap by modulating the flux.

Abstract: The method for operating a frequency converter (26) of a generator (14) in particular of a wind energy turbine (10), in the event of a substantial grid voltage drop, wherein the frequency converter (26) comprises a generator-side power converter (32), to be connected to the generator (14), a grid-side power converter (28) to be connected to the voltage grid (18), and a DC link circuit (30) for connecting the generator-side power converter (32) to the grid-side power converter (28), comprises the step of generating the amount of reactive current to be supplied to the grid (18) by controlling the frequency converter (26).

Abstract: The invention relates to Method of operating a wind turbine, wherein rotor windings of an induction generator, which comprises stator coils coupled to a voltage grid, fed with rotor currents by a feed-in unit are driven by a rotor of the wind turbine; wherein the frequencies of the fed-in rotor currents are controlled depending on the rotor rotation frequency and the feed-in unit is electrically decoupled from the rotor windings in the case predetermined variations of the grid voltage amplitude and the rotor current feed-in is resumed after the decoupling caused by the variation of the grid voltage amplitude, when the currents generated in the rotor windings by the variation have declined to a predetermined value.

Abstract: A wind turbine generator includes at least one rotating member, at least one stationary member, and a clearance gap control system. The stationary member is positioned such that a clearance gap is defined between a portion of the rotating member and a portion of the stationary member. The clearance gap is configured to facilitate transmitting a controllable magnetic flux therethrough. The control system includes at least one clearance gap measurement assembly, at least one power converter, and at least one controller. The controller is coupled in electronic data communication with the assembly and the converter and is configured to modulate a dimension of the gap by modulating the flux.

Abstract: A method of operating a wind turbine, wherein the wind turbine may include rotor windings of an induction generator, which includes stator coils coupled to a voltage grid, fed with rotor currents by a feed-in unit are driven by a rotor of the wind turbine; wherein the frequencies of the fed-in rotor currents are controlled depending on the rotor rotation frequency and the feed-in unit is electrically decoupled from the rotor windings in the case predetermined variations of the grid voltage amplitude and the rotor current feed-in is resumed after the decoupling caused by the variation of the grid voltage amplitude, when the currents generated in the motor windings by the variation have declined to a predetermined value.

Abstract: The method for operating a frequency converter (26) of a generator (14) in particular of a wind energy turbine (10), in the event of a substantial grid voltage drop, wherein the frequency converter (26) comprises a generator-side power converter (32), to be connected to the generator (14), a grid-side power converter (28) to be connected to the voltage grid (18), and a DC link circuit (30) for connecting the generator-side power converter (32) to the grid-side power converter (28), comprises the step of generating the amount of reactive current to be supplied to the grid (18) by controlling the frequency converter (26).

Abstract: A wind turbine. The wind turbine includes a blade pitch control system to vary a pitch of one or more blades and a turbine controller coupled with the blade pitch control system. A first power source is coupled with the turbine controller and with the blade pitch control system to provide power during a first mode of operation. Uninterruptible power supplies coupled to the turbine controller and with the blade pitch control system to provide power during a second mode of operation. The turbine controller detects a transition from the first mode of operation to the second mode of operation and causes the blade pitch control system to vary the pitch of the one or more blades in response to the transition.

Abstract: A wind turbine. The wind turbine includes a blade pitch control system to vary a pitch of one or more blades and a turbine controller coupled with the blade pitch control system. A first power source is coupled with the turbine controller and with the blade pitch control system to provide power during a first mode of operation. Uninterruptible power supplies coupled to the turbine controller and with the blade pitch control system to provide power during a second mode of operation. The turbine controller detects a transition from the first mode of operation to the second mode of operation and causes the blade pitch control system to vary the pitch of the one or more blades in response to the transition.