Aspects of the present invention relate to a method for controlling a renewable power plant connected to a power network to reduce deviation of a measured frequency of the power network from a target frequency. The method comprises determining a forecasted power gradient over a forecast interval defined between a first time point and a second time point, and, at a third time point during the forecast interval, controlling the power plant to output active power according to a minimum active power level if the measured frequency at the third time point is below the target frequency, controlling the power plant to output active power according to a maximum active power level if the measured frequency at the third time point is above the target frequency. The maximum and minimum active power levels are based on the forecasted power gradient.

A method for connecting a power transformer, located between an inverter of a wind turbine and an electrical grid, to the electrical grid; the method comprises the steps gradually increasing a voltage at a primary side of the transformer from a low starting voltage to a target voltage equal or close to a nominal voltage of the transformer, by means of the inverter of the wind turbine or by means of an auxiliary inverter, thereby increasing the voltage at a secondary side of the transformer, wherein the gradually increasing of the voltage uses energy of an internal energy storage device, connecting the secondary side of the transformer to the electrical grid after predefined target conditions have been reached.

Provided is a control circuit of a converter, in particular a power converter of a wind power installation, configured to control the converter in such a way that the converter emulates a behavior of a synchronous machine. The control circuit includes a power module for calculating a power change depending on a detected power and a correction module for setting a power set point, in particular for the converter, depending on the calculated power change.

The invention relates to a method for controlling a power generating unit such as a wind turbine which is configured as a virtual synchronous machine. Capacitor voltage signals obtained from voltage measurements of output capacitors are filtered in order to reduce a magnitude of an impedance peak and/or shift the impedance peak where the impedance peak is present in an impedance characteristic of the output of the power generating unit. Filter compensated voltage signals obtained from the output capacitors are combined with a voltage magnitude reference to obtain filtered capacitor voltage signals used for controlling the line side converter and thereby affect the impedance peak in a desired way.

A hybrid electrical power supply control system for providing electrical energy to at least one load. The load may alternate between a first low energy consuming operational modus and a second high energy consuming operational modus. The control system may include a first power source comprising at least one battery unit and a second power source comprising at least one energy harvesting unit and arranged to harvest and convert energy into Direct Current, DC, energy, and wherein the converted DC energy is stored in a charge collecting unit. The control system further includes an operational modus detecting unit and a power source switching unit, connected to the operational modus detecting unit and arranged to alternately connect the first power source and the second power source to the load.

A system and method provide integrated carbon-negative, geothermal-based, energy generation and storage. The embodiments produce dispatchable electricity at grid-scale by storing excess energy from the grid and generating its own energy. The excess energy may be taken from solar and wind sources. In one aspect, the subject technology is energy storage, energy generation, carbon utilization and sequestration, all in one. The technology has very high round-trip efficiency of storing energy and is carbon-negative which makes it far more sustainable than any competing energy storage technology.

The present disclosure includes methods and apparatus for HVDC power distribution. A control apparatus is described for controlling a frequency set-point for a first AC network electrically connected to a first HVDC station to regulate active power. The controller has a frequency controller operable in a first mode of operation to determine a frequency set-point (Fref) for the first AC network based on a measured DC voltage at the first HVDC station. A disturbance detector is configured to monitor the measured value of DC voltage at the first HVDC station (VDC1) for a predetermined characteristic indicative that a variation in measured DC voltage does correspond to a known modulation applied to the DC voltage by a second HVDC station. The frequency controller is configured to determine the frequency set-point (Fref) for the first AC network based on a measured value of DC voltage (VDC1) if said predetermined characteristic is detected, and to control the frequency set-point to a predetermined default frequency if said predetermined characteristic is not detected.

The present application provides a method and a system for controlling continuous low voltage ride-through and high voltage ride-through of a permanent magnet direct-driven wind turbine. The method includes: determining a transient time period during which the wind turbine is transitioned from a low voltage ride-through state to a high voltage ride-through state; controlling the wind turbine to provide, during the transient time period, a gradually increasing active current to the point of common coupling; and controlling the wind turbine to provide, during the transient time period, a reactive current to the point of common coupling according to an operation state of the wind turbine before the low voltage ride-through state.

A method for mitigating voltage disturbances at a point of interconnection (POI) of a grid-forming inverter-based resource (IBR) due to flicker includes receiving a voltage reference command and a voltage feedback. The voltage feedback contains information indicative of the voltage disturbances at the POI due to the flicker. The method also includes determining a power reference signal for the IBR based on the voltage reference command and the voltage feedback. Moreover, the method includes generating a current vector reference signal based on the power reference signal, the current vector reference signal containing a frequency component of the voltage disturbances. Further, the method includes generating a transfer function of a regulator based on the frequency component to account for the flicker effect. In addition, the method includes generating a current vector based on a comparison of the current vector reference signal and a current vector feedback signal. Thus, the method includes regulating a voltage vector command using the current vector to mitigate the voltage disturbances.

The disclosure is directed to methods and systems for provisioning mobile electric vehicles with various operational settings data transmitted over the air. A vehicle or its components may operate according to operational settings corresponding to operational settings data included in the vehicle components. A server that is remote to the vehicle may comprise operational settings data and may transmit operational settings data to the vehicle. The server may transmit operational settings data automatically, such as on a periodic basis, in response to a request, such as from a user or from a vehicle component or anytime new or updated operational settings data are available for the vehicle or its components.