Abstract: A method and apparatus for minimizing circulating currents on a power distribution line. In one embodiment, the method comprises dynamically adjusting a turns ratio of a tap changing transformer, the tap changing transformer coupled to a power grid distribution line that is also coupled to a plurality of microgrid branches wherein at least one microgrid branch of the plurality of microgrid branches comprises a distributed energy resource (DER), based on a reactive power measured locally to the tap changing transformer, to minimize current circulating on the power grid distribution line.

Abstract: A system and apparatus for use in energy conversion. In one embodiment, the apparatus comprises a gateway remotely located from an inverter and having (i) a first terminal for coupling to AC wiring upon which the inverter couples AC power, wherein the AC power is generated by the inverter from DC power, and wherein the gateway obtains data pertaining to operation of the inverter via the first terminal, and (ii) a second terminal for coupling information related to the data to an external monitor, remotely located with respect to the gateway, via a communications network.

Abstract: A method and apparatus for power conversion comprising a three-port converter comprising a DC port for coupling to an external DC line, an AC port for coupling to an external AC line, and a storage port, internal to the three-port converter, for storing excess energy and discharging needed energy during power conversion, wherein the storage port is located on a DC-side of the three-port converter and is decoupled from the DC port such that a voltage on the storage port can be controlled independently of a DC voltage on the DC port.

Abstract: Exemplary embodiments of the present invention are drawn to a method and apparatus for securing a segmented cable in manufacturing and for shipping and storage. In some embodiments, the apparatus comprises two or more fixtures, each comprising a plurality of locking receptacles along a body of each fixture, wherein each of the plurality of locking receptacles comprises a locking mechanism to secure a connector of a plurality of connectors on a power cable.

Abstract: Method and apparatus for generating power. In one embodiment the method comprises determining a value of a DC parameter pertaining to a DC power source providing DC power to an inverter; comparing the value to a threshold; and operating the inverter to generate positive power or negative power based on a result of comparing the value to the threshold.

Abstract: Apparatus and system for powering an isolated gate driver. In one embodiment, the apparatus comprises a gate driver power supply unit (PSU), coupled to a transistor and to an isolated gate driver that couples control signals to the transistor, for (i) harnessing energy from commutation action across the transistor, and (ii) using the harnessed energy to power the isolated gate driver.

Abstract: A method and apparatus for setting a virtual impedance ratio of a power conditioning unit (PCU). In one embodiment, the method comprises applying a disturbance to a virtual AC voltage of a power conditioning unit (PCU) operating in a virtual impedance droop control mode in which the PCU appears, from the perspective of a power grid coupled to the PCU, as a virtual AC voltage source in series with a virtual impedance; measuring the phase of the applied disturbance on the power grid; comparing the measured phase of the applied disturbance on the power grid to the phase of the disturbance; and adjusting, when the measured phase of the applied disturbance on the power grid differs from the phase of the disturbance by more than a threshold amount, a ratio of a resistive impedance of the virtual impedance to an inductive impedance of the virtual impedance.

Abstract: A method and apparatus for multi phase shift control of a power converter. In one embodiment, the method comprises controlling a phase shift between a left leg and a right leg of a first bridge of the power converter during operation of the power converter; and controlling a phase shift between the first bridge and a second bridge of the power converter during the operation of the power converter, wherein the phase shift between the left and the right legs and the phase shift between the first and the second bridges are controlled based on an input voltage of the power converter and a required output voltage of the power converter.

Abstract: An apparatus for mechanically coupling a power conditioner to a photovoltaic (PV) module frame. In one embodiment, the apparatus comprises: a bracket, adapted for mechanically coupling the power conditioner to the PV module frame, comprising at least one inner-flange tab and at least one outer-flange tab for trapping a flange of the PV module frame between them; and at least one self-locking mounting structure for locking the bracket to the PV module frame without requiring any holes in the PV module frame.

Abstract: Method and apparatus for controlling power conditioners in a distributed resource island. In one embodiment, the method comprises comparing, at a power conditioner operating in a de-energized state, an input of the power conditioner to an input threshold, wherein the power conditioner is coupled to an islanded grid; operating the power conditioner, when the input exceeds the input threshold, in a soft-grid mode to generate a touch-safe AC voltage that is coupled to the islanded grid; comparing, by the power conditioner, an impedance of the islanded grid to a grid impedance range; comparing, by the power conditioner, load demand of the power conditioner to an activate threshold; and activating the power conditioner, when the impedance is within the grid impedance range and the load demand exceeds the activate threshold, to operate proximate its nominal output voltage.

Abstract: A photovoltaic (PV) system includes module-level power electronic (MLPE) devices that produce energy. The PV system includes a gateway to receive and send data to MLPE devices. The gateway also connects the PV system with a network, such as a local area network, that allows access to the Internet. The gateway provides functionality within the PV system to perform various processes to improve operation of MLPE devices.

Abstract: An energy control circuit is provided. The energy control circuit includes an input circuit; an output circuit; an energy storage circuit coupled between the input circuit and the output circuit; and a controller coupled to the input circuit and output circuit for controlling an amount of energy stored in the energy storage circuit and for controlling a waveform generated by the output circuit using energy stored in the energy storage circuit.

Abstract: An inverter includes a transformer that includes a first winding, a second winding, and a third winding, a DC-AC inverter electrically coupled to the first winding of the transformer, a cycloconverter electrically coupled to the second winding of the transformer, an active filter electrically coupled to the third winding of the transformer. The DC-AC inverter is adapted to convert the input DC waveform to an AC waveform delivered to the transformer at the first winding. The cycloconverter is adapted to convert an AC waveform received at the second winding of the transformer to the output AC waveform having a grid frequency of the AC grid. The active filter is adapted to sink and source power with one or more energy storage devices based on a mismatch in power between the DC source and the AC grid.

Abstract: A method and apparatus for autonomously operating a microgrid power generator. In one embodiment, the method comprises obtaining a first measurement of at least one grid parameter of a microgrid transmission line coupled to a power generator in a microgrid; comparing the first measurement to a turn-on threshold; initiating, when the first measurement is less than the turn-on threshold, power generation by the power generator; obtaining, after initiation of the energy generation, a second measurement of the at least one grid parameter of the microgrid transmission line; comparing the second measurement to a shut-down threshold that is greater than the turn-on threshold; and stopping, when the second measurement exceeds the shut-down threshold, the power generation by the power generator.

Abstract: A system and apparatus for autonomous charge balancing of an energy storage device of the microgrid. In one embodiment the apparatus comprises the energy storage device; and a power conditioner, coupled to the energy storage device, comprising a droop control module for operating the power conditioner, during an autonomous mode of operation, such that the state of charge of the energy storage device is autonomously driven toward the state of charge of at least one other energy storage device of the microgrid.

Abstract: A system and method for establishing communication between a controller and a plurality of inverters comprises determining a response time window length and broadcasting a response request to the array of inverters that includes the response time window length. Each inverter, in response to receiving the response requests, transmits a response to the controller at a randomly determined response time within the response time window. In response to receiving an acknowledgement from the controller, the responding inverter may ignore subsequent response requests. The controller may adjust the response time window and broadcasts the new response time window until no inverter response is received for a pre-determined number of response time windows.

Abstract: A photovoltaic module-mounted AC inverter circuit uses one or more integrated circuits, several power transistors configured as switches, several solid-dielectric capacitors for filtering and energy storage, several inductors for power conversion and ancillary components to support the above elements in operation. The integrated circuit includes all monitoring, control and communications circuitry needed to operate the inverter. The integrated circuit controls the activity of pulse-width modulated power handling transistors in both an input boost converter and a single-phase or multi-phase output buck converter. The integrated circuit also monitors all power processing voltages and currents of the inverter and can take appropriate action to limit power dissipation in the inverter, maximize the available power from the associated PV module and shut down the inverter output if the grid conditions so warrant.

Abstract: An apparatus and system for presenting a power output from a photovoltaic (PV) module. In one embodiment, the apparatus comprises a connector assembly comprising (i) an encapsulated ribbon egress, integrated with the PV module, comprising a plurality of PV module substring interconnects electrically coupled to a plurality of PV cells of the PV module; and (ii) a connector comprising a two-pole DC electrical output that is electrically coupled to the plurality of PV module substring interconnects.

Abstract: A method and apparatus for power converter current control. In one embodiment, the method comprises controlling an instantaneous current generated by a power converter that is part of an AC battery such that (i) the 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, wherein real and reactive phasor currents for the power converter are indirectly controlled by modifying amplitude and phase of a virtual AC voltage waveform that defines the virtual AC voltage source, and (ii) active power flow is prioritized while the AC battery is operating in a charge mode.

Abstract: A system and method for mapping relative positions of a plurality of alternative energy source modules. In one embodiment, the method includes injecting a first contribution current into a power grid by a first alternative energy source module of the plurality of alternative energy source modules and determining an output voltage for each of the plurality of alternative energy source modules. The method also includes constructing a data structure of the relative positions of the plurality of alternative energy source modules employing the output voltage for ones of the plurality of alternative energy source modules.