The system and method described herein provide grid-forming control of a power generating asset having a generator, such as a double-fed generator, connected to a power grid. Accordingly, a stator-frequency error is determined for the generator. The components of the stator frequency error are identified as a damping component corresponding to a tower damping frequency and a stator component. Based on the stator component, a power output requirement for the generator is determined. This power output requirement is combined with the damping power command to develop a consolidated power requirement for the generator. Based on the consolidated power requirement, at least one control command for the generator is determined and an operating state of the generator is altered.

Systems and methods may use a low speed controller in addition to an economic optimizer to achieve long-term objectives without significantly disrupting or destabilizing an electrical system. Specific long-term objectives include maximizing a capacity factor incentive and regulating battery degradation, but the methods and systems herein can be extended to more long-term objectives. A low speed controller can adjust one or more parameters of a cost function based on the relation between the projected state of the electrical system and the one or more parameters to effectuate a change to the electrical system to attempt to comply with the long-term objective.

A method for feeding electrical power into an electrical supply network having a network voltage with a network frequency by means of a converter-based generator, in particular by means of a wind power system, is provided. The method includes estimating a converter proportion of a network section of the electrical supply network. The converter proportion denotes a ratio of power fed in by means of converters to total power fed in. The method includes feeding the electrical power into the electrical supply network in a normal mode depending on the estimated converter proportion, activating a first support mode depending on the estimated converter proportion in accordance with a first activation condition, and activating a second support mode depending on the estimated converter proportion in accordance with a second activation condition, which is different than the first activation condition.

A method for controlling a power converter, which in particular has partial power converters connected in parallel, is provided. The method includes determining a nominal voltage for the power converter; and dividing an output voltage for the power converter into a number of, in particular equal, voltage ranges. The voltage ranges are limited by a discrete upper voltage limit and a discrete lower voltage limit and the voltage ranges can be adjusted by switching the power converter, in particular the partial power converters. The method includes allocating the nominal voltage a voltage range with a discrete upper and lower voltage limits; allocating a first switch setting to the lower voltage limit; allocating a second switch setting to the upper voltage limit; and switching between the first switch setting and the second switch setting so that the power converter generates an actual voltage corresponding to the nominal voltage.

Provided is a method for feeding electric power into an electricity supply grid via a connection node by way of a converter-controlled infeed unit, in particular by way of a wind power installation or a wind farm. The grid has a grid voltage and a grid frequency and is characterized by a grid nominal voltage and a grid nominal frequency. The grid voltage of the grid is acquired, a delayed differential angle is ascertained on the basis of the acquired grid voltage. The delayed differential angle corresponds to a difference between an acquired phase signal that indicates a temporal profile of a phase angle of the grid voltage and a phase signal that is delayed with respect to the acquired phase signal. A grid impedance effective for the connection node is acquired, and an infeed power is predefined based on the delayed differential angle and based on the impedance.

A method for controlling a wind farm to damp low-frequency electrical oscillations, in particular subsynchronous resonances, in an electrical supply grid having a grid voltage with a nominal grid frequency is provided. The wind farm comprises at least one wind turbine connected to the electrical supply grid. The method includes sensing at least one low-frequency electrical oscillation of the electrical supply grid; determining an oscillation characteristic of each of the at least one sensed oscillation, the oscillation characteristic describing at least one property of the sensed oscillation; specifying an active-power damping signal and/or a reactive-power damping signal for damping the at least one low-frequency oscillation; feeding in an active power component in accordance with the active-power damping signal or a reactive power component in accordance with the reactive-power damping signal, the active-power damping signal and the reactive-power damping signal being specified in dependence on the determined oscillation characteristic.

Methods and apparatuses for controlling reactive power of a wind turbine, and a wind farm are provided. An exemplary method includes: obtaining operation data of single wind turbines in a wind turbine group at the current time point; determining the total maximum capacitive reactive capacity and total minimum inductive reactive capacity, satisfying a safety constraint condition at the next time point, of the wind turbine group; calculating a deviation value of a wind turbine group reactive instruction at the current time point; and updating the wind turbine group reactive instruction on the basis of the acquired, determined, and calculated data so as to perform reactive power control.

Enabling control of wind turbines is provided. The method comprises receiving power production signals from wind turbines comprising a wind farm and estimating wake travel times from upstream wind turbines to downstream turbines. Correlations of the power production signals are calculated among all pairs of wind turbines in the wind farm. Wind turbines with a power production correlation above a specified threshold at an expected time are considered to have wake interaction. A probability density function of northing directions is calculated for the wind turbine pairs with wake interaction. A determination is made whether the probability density function has a dominant direction. Responsive to the probability density function having a dominant direction, the wind turbine pairs with wake interaction are identified as turbine clusters. A control strategy is applied to each turbine cluster as an operational unit to optimize power production of the wind farm.

A method for determining when a connection of a power system to a grid has been disconnected. The method includes the power system supplying a first amount of reactive power to the grid to which the power system is connected, and the power system determining if there is a frequency change within the grid. This includes if the frequency change does not exceed a predetermined threshold, the power system supplying a second amount of reactive power to the grid, and if the frequency exceeds a predetermined threshold, the power system supplying a first amount of reactive power to the grid.

A communication device is provided with: a first communication part that is connected to an energy storage device or a power supply related apparatus and communicates with the energy storage device or the power supply related apparatus; an acquisition part that acquires information including a state of the energy storage device or the power supply related apparatus on the basis of a set timing; a change acceptance part that accepts a change in the timing and changes the timing; and a transmission part that transmits, at a timing after the change, the information acquired by the acquisition part to a first apparatus by using a second communication part communicatively connected to the first apparatus.