A method for operating a power generating facility connected to a power distribution grid having an uncertain power generation condition includes predicting a probabilistic power flow forecast in a transmission line of the power distribution grid for a period of time, wherein the transmission line is electrically coupled to the power generating facility, predicting, using the probabilistic power flow forecast, a probability of congestion over the transmission line of the power distribution grid during the period of time, generating a mitigation plan, including a load adjustment on the transmission line, using the probability of congestion predicted over the transmission line and a thermal limit constraint of the transmission line, wherein the mitigation plan balances load adjustment and an overlimit line capacity on the transmission line, and controlling the power generating facility, using the mitigation plan, to achieve load modification and mitigate the probability of congestion predicted in the transmission line.

A method for assisting control of an electrical supply grid) or a portion thereof is provided. The method includes recording system states of the grid and/or influencing the grid, transmitting the states to a central evaluation and/or control unit and/or between other subscribers, including wind turbines and/or wind farms that supply the grid, for use in controlling their supply to the grid. The method includes controlling the grid on the basis of the transmitted states. Fundamentally identical states are simultaneously recorded at multiple recording locations associated with the grid and the recording of at least one of the states at a respective recording location is performed by a turbine and/or farm and the turbine or farm recording a state at one recording location and the turbine or farm recording a state at another recording location are independent at least such that they supply to the grid at different points.

A method for assisting control of an electrical supply grid) or a portion thereof is provided. The method includes recording system states of the grid and/or influencing the grid, transmitting the states to a central evaluation and/or control unit and/or between other subscribers, including wind turbines and/or wind farms that supply the grid, for use in controlling their supply to the grid. The method includes controlling the grid on the basis of the transmitted states. Fundamentally identical states are simultaneously recorded at multiple recording locations associated with the grid and the recording of at least one of the states at a respective recording location is performed by a turbine and/or farm and the turbine or farm recording a state at one recording location and the turbine or farm recording a state at another recording location are independent at least such that they supply to the grid at different points.

A method for feeding electric power into an electrical supply grid by means of a local feed unit. The feed unit is connected to a grid link point connected to a transformer point directly or via a supply connection. The transformer point is connected to a grid section via a transformer. The method includes feeding electrical real power into the electrical supply grid at the grid link point, feeding electrical reactive power into the electrical supply grid at the grid link point, detecting a change to be made in the real power to be fed in, and changing the fed-in real power in accordance with the detected change to be made. The method includes limiting a change in the fed-in reactive power over time when changing the fed-in real power and/or immediately thereafter or temporarily activating voltage control on the basis of the change in the fed-in real power.

A method for feeding electric power into an electrical supply grid by means of a local feed unit. The feed unit is connected to a grid link point connected to a transformer point directly or via a supply connection. The transformer point is connected to a grid section via a transformer. The method includes feeding electrical real power into the electrical supply grid at the grid link point, feeding electrical reactive power into the electrical supply grid at the grid link point, detecting a change to be made in the real power to be fed in, and changing the fed-in real power in accordance with the detected change to be made. The method includes limiting a change in the fed-in reactive power over time when changing the fed-in real power and/or immediately thereafter or temporarily activating voltage control on the basis of the change in the fed-in real power.

A plurality of photovoltaic (PV) modules are configured into a PV string to generate a PV string voltage in a solar power system. The number of PV modules per PV string is based on operating conditions at the solar power system site and cause the PV string voltage to exceed a maximum voltage specification when operating at the lowest expected ambient temperature at the site, but only exceeds the maximum voltage specification for a limited number of occurrences for which the operating conditions at the site cause the PV string voltage to exceed the maximum voltage specification. Under control of a string voltage control circuit, voltage bypass circuits selectively bypass the bypass photovoltaic module so as to eliminate the PV module from the PV string voltage when the operating conditions at the site cause the PV string voltage to exceed the maximum voltage specification.

A plurality of photovoltaic (PV) modules are configured into a PV string to generate a PV string voltage in a solar power system. The number of PV modules per PV string is based on operating conditions at the solar power system site and cause the PV string voltage to exceed a maximum voltage specification when operating at the lowest expected ambient temperature at the site, but only exceeds the maximum voltage specification for a limited number of occurrences for which the operating conditions at the site cause the PV string voltage to exceed the maximum voltage specification. Under control of a string voltage control circuit, voltage bypass circuits selectively bypass the bypass photovoltaic module so as to eliminate the PV module from the PV string voltage when the operating conditions at the site cause the PV string voltage to exceed the maximum voltage specification.

A method of controlling a microgrid comprises receiving, by a power management system, PMS, of the microgrid, operating point values for a plurality of controllable assets. The method comprises determining, by the PMS, an asset headroom. The method comprises determining, by the PMS, a modified operating point value that is dependent on the received operating point value of the controllable asset, the determined asset headroom of the controllable asset, and a total power offset of the microgrid. The method comprises controlling, by the PMS, the controllable assets for which the modified operating point values have been determined in accordance with the modified operating point values.

The present disclosure discloses an offshore wind farm low-frequency alternating-current uncontrolled rectification electric power transmission system, comprising an onshore converter station and an offshore alternating-current system. The offshore alternating-current system comprises wind turbine generators, alternating-current submarine cables, a confluence bus, and offshore booster stations; the onshore converter station comprises a wind field side alternating-current bus, an alternating-current system side alternating-current bus, an alternating-current filter, an energy dissipation device, a rectifier, and a converter; the rectifier is composed of a three-phase six-pulse uncontrolled rectifier bridge, and the converter may be an MMC or an LCC; the rated frequency of the offshore alternating-current system is selected to be close to 10 Hz.

The present disclosure discloses an offshore wind farm low-frequency alternating-current uncontrolled rectification electric power transmission system, comprising an onshore converter station and an offshore alternating-current system. The offshore alternating-current system comprises wind turbine generators, alternating-current submarine cables, a confluence bus, and offshore booster stations; the onshore converter station comprises a wind field side alternating-current bus, an alternating-current system side alternating-current bus, an alternating-current filter, an energy dissipation device, a rectifier, and a converter; the rectifier is composed of a three-phase six-pulse uncontrolled rectifier bridge, and the converter may be an MMC or an LCC; the rated frequency of the offshore alternating-current system is selected to be close to 10 Hz.