A method and apparatus for power converter current control. In one embodiment, the method comprises controlling an instantaneous current generated by a power converter such that that power converter appears, from the perspective of an AC line coupled to the power converter, as a virtual AC voltage source in series with a virtual impedance.

Disclosed are a control method and system for a parallel converter system, including a common AC voltage controller and a separate current controller for each converter; the AC voltage controller generates an active current, a wattless current, and a system voltage phase reference value and, by means of communication, sends same to the current controller of each converter in island control mode to be a converter control signal; the active and wattless current outputted by each converter, along with the corresponding current reference value, accomplish the objective of the parallel converter system collectively controlling the amplitude and frequency of an AC bus voltage. The method and system are highly reliable and effectively ensure the synchronization of a plurality of converters.

A system for supplying energy to electrically operated mining machines, which system includes a hybrid power-generation arrangement for outputting electricity for the mining machines, a cable routing system for routing at least one power cable from the hybrid power-generation arrangement to the mining machines, and at least one energy source for supplying energy to the hybrid power-generation arrangement, wherein the hybrid power-generation arrangement has an electrochemical energy store, a fuel cell and an internal combustion engine generator.

A method of assessing dynamic flexibility for a virtual power plant, which belongs to the technical field of operating and controlling a power system. The method equals a virtual power plant to an equivalent energy storage device and an equivalent generator and decouples a network constraint condition between the two types of devices through a Robust optimization method. Subsequently, by using a two-stage Robust optimization algorithm, parameters of the equivalent energy storage device and the equivalent generator are calculated and finally accurate depiction is realized on adjusting ability of a distributed resource, so as to provide a scientific decision basis for the virtual power plant to participate in grid control, such that it has a great value in an actual application.

A method, apparatus and system are provided to coordinate, manage, and optimize the electrical loads across all subsystems behind a given meter. In this approach, which is sometimes referred to herein as intelligent demand optimization, the optimized capacity needs of each subsystem are assessed in real-time, along with the available capacity of the meter and the current billing period peak. Power is then distributed dynamically to each subsystem to reduce the overall peak.

A power supply system according to the present embodiment includes a plurality of first power converters configured to supply power according to dispatching characteristics of power to be supplied to a load, and a plurality of control devices each configured to associate a change ratio of active power to an output frequency of each of the first power converters with the dispatching characteristics and control each of the first power converters based on the change ratio.

Systems, methods, and devices relating to operating a power generation facility to contribute to the stability of the power transmission system. A controller operates on the power generation facility to modulate real power or reactive power or both in a decoupled manner to contribute to the stability of the power transmission system. Real power produced by the power generation facility can be increased or decreased between zero and the maximum real power available from the PV solar panels, as required by the power system. Reactive power from the power generation facility can be exchanged (injected or absorbed) and both increased or decreased as required by the power transmission system. For solar farms, the solar panels can be connected or disconnected, or operated at non-optimal power production to add or subtract real or reactive power to the power transmission system.

Systems, methods, and devices relating to operating a power generation facility to contribute to the stability of the power transmission system. A controller operates on the power generation facility to modulate real power or reactive power or both in a decoupled manner to contribute to the stability of the power transmission system. Real power produced by the power generation facility can be increased or decreased between zero and the maximum real power available from the PV solar panels, as required by the power system. Reactive power from the power generation facility can be exchanged (injected or absorbed) and both increased or decreased as required by the power transmission system. For solar farms, the solar panels can be connected or disconnected, or operated at non-optimal power production to add or subtract real or reactive power to the power transmission system.

A system is provided having one or more charging stations that are electrically coupled with a power distribution grid and that may selectively couple with one or more energy storage devices; and a controller that may control transfer of electric power between the one or more charging stations, the one or more energy storage devices, and the power distribution grid. The controller may determine the amount of electric power transferred based at least in part on one or both of an assessment value.

A method and an apparatus for controlling wind turbine power. The method includes: determining a compensation value for target active power based on a power difference between a net grid-connected power and the target active power; determining a setpoint value of active power based on the target active power and the compensation value; and performing a current-varying control and a pitch control based on the setpoint value of active power.