The present disclosure relates to a generator control device and a method to control the output power of at least one generator connected to an electric grid. It is an object of the invention to provide a fast solution to counteract electric grid frequency instabilities. Disclosed is a generator control device and method to control the output power of at least one turbogenerator driven by a turbine connected to an electric grid with a static frequency converter. The generator control device includes a frequency measuring device to measure the electric grid frequency f.sub.el, and the static frequency converter is configured to operate the turbogenerator in dependency of the measured electric grid frequency f.sub.el.

Systems, methods, and computer program products for providing an inertial response by a wind power system to power fluctuations in an electrical grid. The system includes a synthetic inertial response generator configured to generate a power offset in response to fluctuations in grid voltage. The power offset signal is generated by determining a quadrature component the grid voltage using an internal reference voltage having an angular frequency and phase angle that is synchronized to the electrical grid by a control loop. The quadrature component is used to determine a synchronous power level. A control loop error signal is produced by the difference between the synchronous power level and the wind turbine system power output. Changes in the grid frequency produce an error signal that is added to the power set point of wind turbine system output controllers to provide a power system inertial power output response.

This method for stabilizing the rotation speed of a hydraulic machine having S-characteristic and comprising a distributor (9) is adapted to modify a water flow, so that the machine can be coupled to a grid. The method comprises the steps of calculating an orientation of the distributor (9); and orienting the distributor according to the calculated orientation. The method further comprises the steps of providing an electric torque to the machine so as to reach a target speed.

A method for controlling a generator of electrical energy connected to a grid connection point of an electrical supply grid, comprising the steps of: regularly feeding electrical reactive power and electrical active power into the electrical supply grid, the generator being operated at a first working point, at which the electrical generator generates electrical reactive power and electrical active power, first interrupting or changing the feeding of the electrical reactive power and/or the electrical active power into the electrical supply grid when there is, or it is indicated that there is, a disruption in the electrical supply grid or a disruption of the feed into the electrical supply grid, resuming the regular feeding of the electrical reactive power and/or electrical active power into the electrical supply grid, the generator performing the resumption at a second working point or being ramped up to the second working point, at which the electrical generator generates and feeds in electrical reactive power and/or electrical active power, and suppressing the resumption of the feeding of the electrical reactive power and/or the electrical active power into the electrical supply grid in such a way that the electrical generator ceases feeding the electrical reactive power and/or the electrical active power for a shut-off period if an interruption has recurred within a predetermined counting time interval, or suppressing the feeding of the electrical reactive power and/or the electrical active power into the electrical supply grid in such a way that the electrical generator ceases feeding the electrical reactive power and/or the electrical active power for a shut-off period if a change of the feed has recurred within a predetermined counting time interval.

A method for supplying power at a network connection point into an electric supply network having a network frequency by means of a converter-controlled generator unit, in particular a wind turbine, comprising the following steps: supplying electric power depending on a control function, wherein the electric power can comprise active and reactive power, and a selection can be made between a normal control function and at least one frequency-maintaining control function differing from the normal control function as a control function, and the normal control function is selected if it has been recognized that the electric supply network is operating in a normal state, and the frequency-maintaining control function is selected if a steady-frequency operating state is present or is being prepared, wherein a steady-frequency operating state describes an operating state particularly of the electric supply network in which the network frequency is to be maintained at a constant value.

It is described a method of estimating additional power output for inertial response that will be available for output throughout a preset inertial response time interval, the method including: obtaining current values of at least a rotational speed of a wind turbine rotor and a power output of the wind turbine; deriving the additional power output based on the obtained current values and a remaining time interval of the preset inertial response time interval, in particular such that the additional power is available for output during the entire predetermined time interval.

The invention provides an adaptive inertial control method based on IIDG (Inverter Interfaced Distributed Generator) of a virtual synchronous motor. By building an adaptive virtual inertia and IIDG output frequency model, the adaptive control sensitive factor is selected from a model according to the virtual synchronous motor dynamic response features; the adaptive inertial upper and lower limits are selected from a model according to the energy storage configuration constraint; the IIDG optimization control strategy is obtained. The control on the grid-connected inverter distributive power supply can be realized, so that the IIDG output is more stable; the interference on the system can be well handled; meanwhile, the characteristics of small overshoot and fast response are realized; the ultra-high dynamic features are realized.

A method and a wind turbine are provided. The wind turbine includes a gearless generator that is a synchronous generator and includes a stator and a generator rotor. The wind turbine includes a generator filter with modifiable filter properties that is coupled to the stator and configured to filter a stator current. The wind turbine includes a filter controller configured to control the generator filter.

A method for operating an electric machine (in particular a wind turbine) having a generator with a rotor and a stator is provided. The method includes: i) evaluating an active damping applied to the electric machine, ii) estimating a damping criterion from the evaluated applied active damping, and iii) shifting a dynamic capacity curve towards a maximum allowed level. The maximum allowed level is based on the damping criterion and a first operation criterion and/or a second operation criterion. Furthermore, the dynamic capacity curve is a dynamic power capacity curve or a dynamic torque capacity curve.

The invention related to a control method for operating a synchronous machine, the machine comprising an exciter connected to a synchronous generator and a controller (40) for controlling the machine field excitation. The method comprises the steps of predefining a stable operation torque derivative range within which a stable operation of the machine occurs, performing a torque measuring or calculating for the machine, calculating the derivative of said torque, determining whether the calculated torque derivative is within the predefined stable operation torque derivative range for the machine, and, if the torque derivative is not within the predefined stable operation torque derivative range, modifying the machine field excitation to bring the torque derivative within the predefined stable operation torque derivative range.