According to one embodiment, an electronic apparatus connectable to a partial power system which is a part of a power system and comprises a first power source apparatus, power supply of the first power source apparatus stopped in response to detecting an islanding of the partial power system, includes: controlling circuitry configured to output to the partial power system a first signal to disable detecting the islanding of the partial power system by the first power source apparatus during at least part of a period during which the partial power system is electrically separated from the power system.

A method for controlling an electrical transmission network including a plurality of DC high-voltage lines and at least three AC/DC converters which are identified by a respective index i and are interconnected by the DC high-voltage lines. Each of the AC/DC converts are connected to an AC voltage bus identified by a respective index i as well as to one of the DC high-voltage lines.

Cooling device 1, in particular a freezer 2, having a closable cooling space 3, an electrically operated cooling circuit, and preferably a cold storage pack 4, wherein the at least one closable cooling space 3 and the cold storage pack 4 can be cooled by the electrically operated cooling circuit. The cooling device has a power distributor 5 for distributing electrical power of at least one regenerative power source 6 to an electrically operated cooling circuit of the cooling device 1 and to at least one further electricity consuming device 7. In addition, the power distributor 5 has a control system with a computing unit 23, a memory 24 and priority logic. The priority logic is used to preferentially supply the electrically operated cooling circuit of the cooling device 1 with electricity if there is a lack of electrical power of the at least one regenerative power source 6.

Cooling device 1, in particular a freezer 2, having a closable cooling space 3, an electrically operated cooling circuit, and preferably a cold storage pack 4, wherein the at least one closable cooling space 3 and the cold storage pack 4 can be cooled by the electrically operated cooling circuit. The cooling device has a power distributor 5 for distributing electrical power of at least one regenerative power source 6 to an electrically operated cooling circuit of the cooling device 1 and to at least one further electricity consuming device 7. In addition, the power distributor 5 has a control system with a computing unit 23, a memory 24 and priority logic. The priority logic is used to preferentially supply the electrically operated cooling circuit of the cooling device 1 with electricity if there is a lack of electrical power of the at least one regenerative power source 6.

A dual-mode combined control method for a multi-inverter system based on a double split transformer is provided. For an extremely-weak grid, the method provides the dual-mode combined control method for a multi-inverter system based on a double split transformer. According to the method, the equivalent grid impedance at a point of common coupling (PCC) of one grid-connected inverter (GCI) in the multi-inverter system based on the double split transformer is obtained with a grid impedance identification algorithm, and the system sequentially operates in a full current source mode, a hybrid mode, and a full voltage source mode according to a gradually increasing equivalent grid impedance, thereby effectively improving the stability of the multi-inverter system based on the double split transformer during variation of the strength of the grid. The method ensures that the system can still operate stably in the extremely-weak grid.

A dual-mode combined control method for a multi-inverter system based on a double split transformer is provided. For an extremely-weak grid, the method provides the dual-mode combined control method for a multi-inverter system based on a double split transformer. According to the method, the equivalent grid impedance at a point of common coupling (PCC) of one grid-connected inverter (GCI) in the multi-inverter system based on the double split transformer is obtained with a grid impedance identification algorithm, and the system sequentially operates in a full current source mode, a hybrid mode, and a full voltage source mode according to a gradually increasing equivalent grid impedance, thereby effectively improving the stability of the multi-inverter system based on the double split transformer during variation of the strength of the grid. The method ensures that the system can still operate stably in the extremely-weak grid.

Controlling a current injected to a power grid from a renewable power plant, in response to a voltage event in the power grid At least a current at a point of common coupling between the renewable power plant and the power grid is determined and provided to a power plant controller (PPC). The power PPC derives individual current setpoint corrections for at least some wind turbines, based on the determined current, and dispatches each derived current setpoint correction to wind turbine controllers of the corresponding wind turbines. The wind turbine controllers control a current output of the respective wind turbines, based on measurements of current and/or voltage at a point of connection between the wind turbine and an internal grid of the renewable power plant, and by taking into account the dispatched current setpoint correction .

Controlling a current injected to a power grid from a renewable power plant, in response to a voltage event in the power grid At least a current at a point of common coupling between the renewable power plant and the power grid is determined and provided to a power plant controller (PPC). The power PPC derives individual current setpoint corrections for at least some wind turbines, based on the determined current, and dispatches each derived current setpoint correction to wind turbine controllers of the corresponding wind turbines. The wind turbine controllers control a current output of the respective wind turbines, based on measurements of current and/or voltage at a point of connection between the wind turbine and an internal grid of the renewable power plant, and by taking into account the dispatched current setpoint correction .

Described herein is a monitoring installation and a monitoring system for monitoring and/or controlling at least one electrical parameter in an electrical supply system, as well as to an associated computer program.

Various embodiments include methods and systems for managing electric power demand distribution across electric power generators in a microgrid. The system may include electric power generator clusters each having electric power generators, electric power output units each electrically connected to at least one of the electric power generator clusters, an energy storage unit electrically connected to an electric power output unit, and a control device. The control device may be configured to determine whether an energy availability of the energy storage unit is less than an energy availability threshold, calculate a sharing multiplication factor for an electric power generator cluster in response to determining that the energy availability of the energy storage unit is less than an energy availability threshold, and calculate a sharing electric power demand for the electric power generator cluster using the sharing multiplication factor.