A power management method includes a step A of specifying an influence of a distributed power supply on a power demand-supply balance by a power management server, the power management server managing a plurality of facilities and the distributed power supply being individually provided in each of the plurality of facilities; and a step B of transmitting distributed power supply information from a local control apparatus to the power management server, the local control apparatus being individually provided in each of the plurality of facilities and the distributed power supply information including information indicating an operation state of the distributed power supply, wherein the step A includes a step of specifying the influence on the power demand-supply-demand balance based on the distributed power supply information.

Provided is a method of controlling wind turbine converters of wind turbines parallel connected at a point of common coupling, the method including: generating for each converter within a same length of a pulse width modulation period a pulse, wherein the pulses start for different converters at different pulse start phases, wherein pulse start phase differences of the pulse start phases between at least two of adjacent converters are unequal.

Provided is a method of controlling wind turbine converters of wind turbines parallel connected at a point of common coupling, the method including: generating for each converter within a same length of a pulse width modulation period a pulse, wherein the pulses start for different converters at different pulse start phases, wherein pulse start phase differences of the pulse start phases between at least two of adjacent converters are unequal.

A method for exchanging or feeding electric power into an electricity supply grid that has a grid frequency using a converter-controlled generator at a grid connection point is provided. The method includes feeding in electric power depending on a control function, where the electric power may comprise active and reactive power, and the control function controls the power depending on at least one state variable of the grid. It is possible to select between a normal control function and a support control function, different from the normal control function, as the control function. The normal control function is selected when it has been detected that the grid is operating stably and the support control function is selected when a grid problem, grid fault or an end of the grid fault has been detected. The support control function controls the fed-in power to counteract an oscillation in the grid.

A photovoltaic power generation system includes a plurality of photovoltaic cell arrays, a plurality of power conditioners connected respectively with the plurality of photovoltaic cell arrays, and a high order device connected to the plurality of power conditioners. The high order device is configured to execute: a first output control to adjust output power of a designated power conditioner to a predetermined output power amount being set in advance; and a second output control to adjust output power from a remaining power conditioner which is other than the designated power conditioner among the plurality of power conditioners. The high order device is configured to execute characteristic-data acquisition to acquire an input/output electrical characteristic of the designated power conditioner during execution of the first output control.

This application provides a photovoltaic power generation system. The system includes at least one first photovoltaic module, a photovoltaic inverter, a first two-way DC/DC converter, and at least one first energy storage unit, and further includes at least one second photovoltaic module or at least one second energy storage unit. The photovoltaic inverter includes a DC/DC converter and a DC-AC inverter, where the DC/DC converter is electrically connected to the at least one first photovoltaic module, and the DC/DC converter is connected to the DC-AC inverter through a direct current bus. For the photovoltaic power generation system, photovoltaic arrays and energy storage devices can be configured flexibly to cope with peaks and troughs of power consumption.

This application provides a photovoltaic power generation system. The system includes at least one first photovoltaic module, a photovoltaic inverter, a first two-way DC/DC converter, and at least one first energy storage unit, and further includes at least one second photovoltaic module or at least one second energy storage unit. The photovoltaic inverter includes a DC/DC converter and a DC-AC inverter, where the DC/DC converter is electrically connected to the at least one first photovoltaic module, and the DC/DC converter is connected to the DC-AC inverter through a direct current bus. For the photovoltaic power generation system, photovoltaic arrays and energy storage devices can be configured flexibly to cope with peaks and troughs of power consumption.

Example electrical power systems include an output for supplying a DC output voltage to a load, a first power source connected with the output to supply DC power to the load, and a second power source connected with the output to supply DC power to the load. The electrical power system is configured to supply DC power to the load using only the first power source when a demand of the load is less than an output capacity of the first power source, and the second power source is configured to maintain an enabled on-state when only the first power source is supplying DC power to the load. Additional electrical power systems and methods are also disclosed.

Example electrical power systems include an output for supplying a DC output voltage to a load, a first power source connected with the output to supply DC power to the load, and a second power source connected with the output to supply DC power to the load. The electrical power system is configured to supply DC power to the load using only the first power source when a demand of the load is less than an output capacity of the first power source, and the second power source is configured to maintain an enabled on-state when only the first power source is supplying DC power to the load. Additional electrical power systems and methods are also disclosed.

The present invention relates to a control unit for a converter, preferably of a power converter of a wind power installation, in particular of an active rectifier of a power converter of a wind power installation, comprising: a primary control module for specifying a setpoint value for the converter; a first secondary control module for controlling the converter, in particular a first converter module of the converter, which second secondary control module is configured to produce a first control signal according to the setpoint value; a second secondary control module for controlling the converter, in particular a second converter module of the converter, which converter module is connected in parallel with the first converter module, which second secondary control module is configured to produce a second control signal according to the first control signal.