The invention relates to a power plant controller for controlling wind turbine generators. More particularly, the invention relates to a method for compensating data obtained from measurements at a connection point to the grid in case of a communication failure where communication of such data is lost or becomes unreliable. The measured data are used in the power plant controller for determining setpoints for controlling the wind turbine generators' production of active and reactive power. In response to detection of a communication fault a new setpoint is determined independently of new measured grid data by reconfiguring parts of the power plant controller.

A method and a control system using the same for coordinating control of a plurality of wind turbines of a wind farm during a fault in a utility grid to which power is to be delivered via at least one cable of the wind farm. The method includes: opening each of the electrical connections; selecting at least one wind turbine of the plurality of wind turbines according to a criteria where a sum of value for active power supply that is available from the selected at least one generator is equal or above a sum of values for active power consumption that is consumable by the energy storage system of the selected at least one wind turbine, the auxiliary equipment of the selected at least one wind turbine and the substation level auxiliary equipment; activating the selected wind turbine; for the selected wind turbine: electrically connecting the power input of its converter to the power output of its generator, electrically connecting the power output of its converter to the power input of its auxiliary equipment, the power input of its energy storage system and the corresponding cable, and electrically connecting the power input of a substation level auxiliary equipment to the cable which is electrically connected to the selected wind turbine; the activated wind turbine acting as active power supply for the substation level auxiliary equipment. The method and the control system using the same provide an effective and economic way of using the power generated by the wind turbine generator for powering the auxiliary equipment of the wind turbine, charging the energy storage system of the wind turbine and powering the substation level auxiliary equipment, during the wind farm operates in an islanding mode.

Disclosed herein are an apparatus for driving converters in a wind power generation system, an apparatus for controlling converters in a wind power generation system, an apparatus for driving switching element modules in a wind power generation system, and an apparatus for controlling switching element modules in a wind power generation system. The apparatus for driving converters in a wind power generation system includes a converter control unit configured to drive a plurality of converters connected in parallel between a generator and a grid, wherein the converter control unit sequentially drives the converters one by one when output power of the grid increases and sequentially stops the operations of the converters one by one when output power of the grid decreases.

Operating a renewable energy generator forming part of a renewable energy power plant. During a fault experienced by a power network: determining an active current set point to enable a reactive current supply boost at the point of connection between the plant and the network, the active current set point being based on a voltage level associated with the generator and on operational characteristics of the generator, plant, power network and/or connecting network; calculating a time period for the reactive current boost, the time period being the maximum time that the active current set point can be maintained for; and controlling the generator during the calculated time period to alter active current output to the determined active current set point, thereby providing the reactive current supply boost at the point of connection.

Provided is a control unit for a converter, in particular of a wind power installation and/or of a wind farm, comprising: an input for receiving a detected voltage and/or a detected current, an input for receiving a voltage set point and/or a current set point, an input for receiving a correction value and a feedback control system which is set up, depending on the detected voltage and/or the detected current and the voltage set point and/or the current set point and the correction value, to produce a reactive power set point for a modulated, preferably amplitude-modulated reactive and/or active power of the converter.

Wind farms and methods for operating wind farms are provided. A wind farm includes a plurality of wind turbine generators. A method includes determining an available reactive power value for each of the plurality of wind turbine generators. The method further includes distributing an individual reactive power command to each of the plurality of wind turbine generators. The individual reactive power command is individually tailored to each wind turbine generator of the plurality of wind turbine generators based on the available reactive power value for that wind turbine generator.

A method for controlling a wind power plant comprising a plurality of wind turbine generators, wherein the method comprises: deriving an estimated value for electrical losses in the wind power plant, deriving a measured value for electrical losses in the wind power plant, based on a difference between an aggregated power production from the plurality of wind turbine generators and a power measurement at a point of common coupling; applying the estimated value for electrical losses and the measured value for electrical losses in an active power control loop, comprising a regulator; and controlling by means of the active power control loop an active power production of the wind power plant at the point of common coupling.

The invention relates to a control system for a wind turbine generator, WTG. The control system defines reactive limits for a reactive power reference for the WTG. The reactive limits are defined as a function of a physical parameter, e.g. the output voltage of the WTG. In case the reactive power reference exceeds the predefined limits, the reactive power reference is limited. By limiting the reactive power reference output voltages which exceed certain output voltage limits may be avoided and, thereby, a disconnection of the WTG from the grid may be avoided.

The present invention relates to a method for operating a wind power facility in order to provide reactive power support to a power grid, the method comprising the step of increasing an amount of reactive power injected into the power grid, decreasing an amount of active power injected into the power grid by a certain amount, and dissipating and/or storing essentially said certain amount of active power in power dissipation and/or power storage means. The wind power facility may comprise a wind turbine or a wind power plant.

The invention relates to a method for controlling a feed arrangement having a wind energy installation for feeding electrical power into an electrical supply system, comprising the following steps: generating electrical power using the wind energy installation from wind, feeding a first proportion of the generated electrical power into the electrical supply system, supplying a second proportion of the generated electrical power to an electrical consumer for consuming the supplied second proportion of the generated electrical power, and wherein, depending on at least one monitored system state and/or depending on the prevailing wind, the second proportion of the generated electrical power which is supplied to the consumer is reduced wholly or partially and the first proportion of the electrical power fed into the electrical supply system is increased correspondingly, and to a corresponding feed arrangement.