A power supply system includes a coupling device including a power conversion device, and one or more power supply units. Each of the power supply units includes a distributed power supply, a first interface outputting DC power to the power conversion device, an individual converter converting the DC power to AC power, and a second interface outputting the AC power output from the individual converter. The power conversion device includes a coupling side converter that converts the direct current power output from the power supply units to AC power, and an interface for outputting the AC power output from the coupling side converter. The power supply system includes a controller for controlling at least one of a corresponding one of the power supply units or the power conversion device based on communication information obtained by communication between the corresponding one of the power supply units or the power conversion device.

A method for describing power output of a cluster of wind and solar power stations considering time-varying characteristics. The error function is employed to characterize the degree of difference in power output within periods, and split-level clustering is used to determine the optimal period division under different period division quantities. The economic efficiency theory is introduced to determine the ideal number of periods, avoiding the randomness and unreasonableness that may result from relying on the subjective determination of the number of clusters. This method can reasonably divide the wind and solar power output period, fully reflecting the time-varying law of wind and solar power generation. The results also can accurately reflect the distribution characteristics of the power output of the power station group at each time period, and the power output each time period shows better reliability, concentration, and practicality.

An electrical network including a power source, a flyback converter, a microcontroller, a PID controller, a voltage boost converter, a pulse width modulator integrated circuit, and a battery. The power source produces a charge with a voltage ranging from about 0.1V to about 0.8V and a power ranging from about 0.3 mW to about 100 mW. The flyback converter functions in discontinuous current mode. The microcontroller monitors the power source voltage, calculates a voltage response, and outputs a control signal for the voltage. The PID controller is a digital PID controller, an analog PID controller, or a combination thereof. The voltage boost converter utilizes the power source voltage and power to provide higher voltage power to the electrical network. The pulse width modulator integrated circuit sets a duty cycle and frequency for the flyback converter. The battery stores excess charge produced by the power source.

A distributed power system including multiple DC power sources and multiple power modules. The power modules include inputs coupled respectively to the DC power sources and outputs coupled in series to form a serial string. An inverter is coupled to the serial string. The inverter converts power input from the serial string to output power. A signaling mechanism between the inverter and the power module is adapted for controlling operation of the power modules.

A distributed power system including multiple DC power sources and multiple power modules. The power modules include inputs coupled respectively to the DC power sources and outputs coupled in series to form a serial string. An inverter is coupled to the serial string. The inverter converts power input from the serial string to output power. A signaling mechanism between the inverter and the power module is adapted for controlling operation of the power modules.

A test and control apparatus, system and method for a wind farm, are provided. The test and control apparatus includes a first communication interface, a second communication interface, and a processor card. The processor card receives, via the first communication interface, a frequency regulation instruction issued by the grid scheduling server, receives operation information of the wind power generation unit via the second communication interface, and calculates, based on the operation information of the wind power generation unit, a first frequency regulation capability of the wind power generation unit performing a frequency regulation without using the first energy storage battery. The processor card sends the frequency regulation instruction to the wind power generation unit without using the first energy storage battery, in a case that the first frequency regulation capability of the wind power generation unit satisfies a requirement of the frequency regulation instruction.

A method for operating at least one wind turbine is provided, the wind turbine being electrically coupled to a power-to-gas converter and an electric grid, wherein a control unit determines a power level for the power generated by at least one generator of the at least one wind turbine and at least partially feeds the generated power to the power-to-gas converter when the determined power level reaches or exceeds a given lower threshold value, wherein the amount of power fed to the power-to-gas converter is kept constant when the determined power level reaches or exceeds a given upper threshold value.

The present disclosure provides a grid forming vector current control system configured to emulate a virtual synchronous machine (VSM). The disclosed system comprises a droop control unit, a current control unit, a virtual admittance unit and a phase locked loop (PLL) unit. The virtual admittance unit and the PLL unit are configured to emulate an inertia of the VSM. A virtual current source is connected in parallel to the VSM.

Provided are an operation limit value management unit managing an operation limit value related to the power flow power of system equipment and a determination unit calculating the power flow state for each set time of the future of a power system based on load dispatching information including a power generation plan value, a predicted output value, and a predicted value of power demand and determining whether or not stable is each power flow state by comparison with the operation limit value. The determination unit sequentially changes the first output power of a first power source defined by the power generation plan value of the first power source and calculates each power flow state based on power including the changed first output power and a predicted value of the output of a second power source.

An energy harvesting circuit for harvesting energy from a medium voltage power line. The energy harvesting circuit includes an input capacitor electrically coupled to the power line and storing power therefrom, and a flyback converter including a primary coil and a secondary coil. The harvesting circuit further includes a switching circuit electrically coupled in series with the primary coil and being operable to electrically connect and disconnect the input capacitor to and from the primary coil, where the switching circuit includes an input voltage regulation feedback circuit for regulating an input voltage provided to the switching circuit from the input capacitor. The harvesting circuit also includes an output capacitor electrically coupled to the secondary coil and the actuator, where the output capacitor is charged by the secondary coil when the switching circuit is closed to provide power to an actuator to close a vacuum interrupter.