A charging system for a vehicle is provided. The charging system is for charging an energy storage system of the vehicle using grid power. The grid power may be an external three-phase AC. The charging system may use field weakening techniques to reduce a peak line-line voltage detected at input terminals of conversion circuitry when a need is determined.

Enhanced network power factor corrective designs are presented that can use corrective devices that achieve long-term, operationally stable mechanical work. Embodiments can utilize reverse-winding induction motor designs with engineerable parameters and configurations for the reverse winding (13) in systems and through methods where an inductive motor (1) can present a current that leads voltage and a leading power factor (16) to correct other existing induction motors (8) in an initial network (9) or be optimized for a particular application. Designs also present a power factor correction that can present a variable correction without altering the character or physical capacitive value of an electrical correction component. Individual induction motors that have leading current and a leading power factor (16) can be provided to improve reverse winding induction motors. Progressive start controls (23) can also be used in a manner that limits inrush current to operational levels with passive current establishment control where reverse winding (13) effects can be used and perhaps even delayed to passively limit and even effect a current decrease while rotational acceleration continues after initial start transition.

A power conversion device (3) is supplied with an electric power from an alternating current power source (1). An active filter device (2), which is a power source quality improvement unit, improves a quality of the alternating current power source (1). A controller (37) limits an operation of the power conversion device (3) so that any one of a power-source electric power, a power-source current, and a power-source harmonic obtained when a failure detection unit (4) detects a failure of the active filter device (2) becomes less than or equal to a maximum value of a corresponding one of the power-source electric power, the power-source current, and the power-source harmonic, the maximum value being obtained when no failure has occurred in the active filter device (2).

Distributed grid network intelligence enables data aggregation at a local control node. In a consumer node, a meter is on a consumer side of a point of common coupling (PCC). The meter can receive one or more external grid inputs and one or more local sensor inputs. The grid inputs can come from sources outside the PCC, and the local sensor inputs monitor conditions at the PCC and/or within the PCC. The meter can identify power demand within the PCC and calculate an output power to generate with a local power converter. The calculation is not simply based on power demand, but on aggregation information, including the one or more external grid inputs, the one or more local sensor inputs, and the power demand for the local load. The local power converter can then output power in accordance with the calculated output power.

A wind turbine system is configured to supply real and reactive power to a grid and includes a tower, and a generator within a nacelle configured atop the tower. The generator is connected to a rotor, which is connected to a hub that includes a plurality of turbine blades mounted thereon. A power converter is configured at a location within the tower. A reactive power compensation device is also configured at the location within the tower, the reactive power compensation device operably configured with the power converter so as to provide reactive power in combination with reactive power generated by the power converter.

Systems and methods for controlling wind turbines providing reactive power are provided. In particular, a method for controlling a power system that includes a controller and one or more wind turbines electrically connected to a power grid through a point of interconnection can be provided. The method can include receiving signals from a sensor associated with the wind turbines. The method can also include determining wind turbines that are operating in low wind or no wind operating conditions based, at least in part, on the one or more of the sensor signals. The method can also include determining a reactive power capability of the wind turbines operating in low wind or no wind conditions and generating control signals based, at least in part, on the reactive power capability of the wind turbines. The method can also include controlling an operational state of the wind turbines based on the control signals.

The present disclosure provides techniques for network-cognizant droop control in power systems, such as a power distribution system. An example device includes a processor configured to determine, based on (i) a model representing a structure of a power system that includes a plurality of energy resources and (ii) an indication of predicted uncontrollable power injections in the power system, for each controllable energy resource in the plurality of energy resources, a respective value of a first droop coefficient and a respective value of a second droop coefficient. The processor may be further configured to cause at least one controllable energy resource in the plurality of energy resources to modify an output power of the at least one energy resource based on the respective value of the first droop coefficient and the respective value of the second droop coefficient.

Aspects of the present invention relate to a method for controlling an amount of reactive current provided from a wind turbine generator to a power grid during an abnormal power grid event, said wind turbine generator comprising a doubly-fed induction generator having a rotor and a stator, and a power converter coupling the rotor to the power grid, the power converter comprising a grid-side inverter, wherein the method comprises the step of balancing the reactive current provided to the power grid between a reactive stator current and a reactive grid-side inverter current, wherein the reactive grid-side inverter current is controlled in accordance with a reactive current capacity of a grid breaker receiving the reactive current provided by the grid-side inverter. Aspects of the present invention also relate to a wind turbine generator being capable of performing the method.

A system includes an uninterruptible power supply (UPS) configured to selectively provide power to a critical load from a grid and an energy storage device, and a grid edge controller configured to communicate with a controller of the UPS and to cause the UPS to operate the energy storage as a distributed energy resource (DER) for the grid while preserving autonomous operation of the UPS to serve the critical load. The grid edge controller may be configured, for example, to maintain a critical reserve in the energy storage device that enables the UPS to maintain the critical load, while allowing the energy storage device to also be used for demand management, frequency regulation and other grid-oriented tasks. The grid edge controller may be configured to control the UPS, for example, via an application programming interface (API) of the controller of the UPS.

A reactive power system comprises a plurality of electrical capacitor banks, with each electrical capacitor bank electrically connected in series with an electrical switch. The electrical switches may be electrically connected to a system such as, for example, an electrical induction motor starter system. A controller is coupled with the motor starter system and each of the electrical switches. The controller, in response to receiving a signal from the motor starter system, determines which of the plurality of electrical capacitor banks from which electrical power should be provided for the motor starter system. For the determined or identified electrical capacitor bank(s), the controller identifies the corresponding electrical switch(es) and communicates a signal to close the switch(es). Closing the switches results in the capacitors in the corresponding electrical capacitor banks to be electrically connected to the motor starter system and to provide current to the motor starter system.