A control device is provided with: a power transfer control means that controls power transfer to and from a DC distribution network; and an exchange means that exchanges, with respect to transfer power to and from the DC distribution network, information indicating an attribute based on a power generation scheme.

This application provides a photovoltaic system and a maximum power point tracking control method for a photovoltaic system. The photovoltaic system includes an MPPT controller and a power converter, and the MPPT controller is connected to the power converter. The MPPT controller is configured to: be connected to a photovoltaic array, and track a global maximum power point MPP of the photovoltaic array. The MPPT controller may be further configured to obtain, when there is a periodic shade for the photovoltaic array, a multi-peak search start moment of global MPPT of the photovoltaic array based on a status of tracking the global MPP of the photovoltaic array in a target time period, so that when the multi-peak search start moment in each MPPT period arrives, the global MPPT of the photovoltaic array is started, to output a working point of the global MPP of the photovoltaic array to the power converter. According to this application, efficiency of obtaining the working point of the global MPP of the photovoltaic array can be improved, and precision of controlling the global MPPT of the photovoltaic array can be improved.

A system and method for combining power from DC power sources. Each power source is coupled to a converter. Each converter converts input power to output power by monitoring and maintaining the input power at a maximum power point. Substantially all input power is converted to the output power, and the controlling is performed by allowing output voltage of the converter to vary. The converters are coupled in series. An inverter is connected in parallel with the series connection of the converters and inverts a DC input to the inverter from the converters into an AC output. The inverter maintains the voltage at the inverter input at a desirable voltage by varying the amount of the series current drawn from the converters. The series current and the output power of the converters, determine the output voltage at each converter.

A facility receives an indication of a rate of energy output sought from a production array of solar panels. The facility controls a power inverter to which the production array is connected to deliver to an electrical grid to which the power inverter is connected a rate of energy output that is based on the indicated rate of energy output.

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.

An apparatus for a system power device utilized in an interconnected power system. The interconnected power system may include multiple system power devices connected to various inter connections of groups of direct currents (DC) from power sources which also may be connected in various series, parallel, series parallel and parallel series combinations for example. The apparatus may include a processor connected to a memory and a communication interface operatively attached to the processor. The communication interface may be adapted to connect to a mobile computing system of a user in close proximity to the system power devices. A graphical user interface (GUI) of the mobile computing system may allow various operational and re-configuration options for the interconnected power system which may include installation, maintenance and monitoring schedules in the interconnected power system when the user of the GUI is in close proximity to the system power devices.

A method includes providing a net consumption trajectory comprising net consumption targets for one or more subperiods of a time period. Each net consumption target indicates a target difference from a beginning of a time period to an end of the subperiod between total consumption and total production or offset. The method also includes generating, for a subperiod of the plurality of subperiods, a set of curtailment actions predicted to achieve the net consumption target for the subperiod and implementing the set of curtailment actions.

Provided is a method of feeding electric reactive power using a wind farm comprising wind turbines. The wind farm feeds a wind farm active power output and the wind farm active power output includes individual plant active power outputs each generated by one of the wind turbines. The wind farm feeds a wind farm reactive power output into the electrical supply network and the wind farm reactive power output includes individual plant reactive power outputs each generated by one of the wind turbines. The method includes determining a total wind farm reactive power output to be fed in by the wind farm and calculating, for each wind turbine, an individual plant reactive power output to be generated. The individual plant reactive power output is determined depending on the individual plant active power output and depending on the wind farm reactive power output to be fed in.

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.