Abstract: A power conversion device according to the aspects of the present technique is presented. The device includes a first converter and a second converter operatively coupled to the first converter. Moreover, the device includes a phase leg operatively coupled between the first converter, the second converter, where the phase leg includes a first unidirectional switch, a second unidirectional switch operatively coupled to the first unidirectional switch, and a first bidirectional switch, where a first end of the first bidirectional switch is operatively coupled to at least one of the first unidirectional switch and the second unidirectional switch.

Abstract: A power inverter system includes a plurality of power semiconductor switching devices. Each switching device includes a corresponding gate turn off resistance configured to increase during starting up periods of the inverter system such that the open circuit voltage of a corresponding power source providing power to the power inverter system does not exceed the switching device blocking voltage ratings during the corresponding switching turn-off periods. The starting up period is the time required to bring the corresponding power source voltage from its open circuit voltage level to a predetermined voltage which constitutes a safe operating condition for the plurality of power semiconductor switching devices.

Abstract: A method and system for detecting an islanding condition in a grid is provided. The method comprises detecting a potential islanding condition in a grid; and, in response to the detected potential islanding condition, ramping up an amount of reactive power, active power, or a combination of active and reactive power that is generated from a power conversion system until the earlier of the power conversion system shutting down or a threshold condition being reached.

Abstract: A power inverter system includes a DC to AC inverter configured to convert DC voltage from a DC power source to AC voltage. A DC link couples the DC power source and the inverter. An inverter pre-charger operates to pre-charge the inverter to achieve a desired DC link voltage prior to connecting the power inverter system to an AC power grid. A phased lock loop synchronizes the pre-charged inverter to the AC power grid prior to connecting the power inverter system to the AC power grid. The pre-charged inverter regulates the DC link voltage to about the minimum voltage level that allows control of AC grid currents via the inverter subsequent to connecting the power inverter system to the AC grid. The inverter operates in a maximum power point tracking control mode only subsequent to a first voltage transient caused by connecting the DC power source to energize the power inverter system.

Abstract: A photovoltaic (PV) energy system includes a pulsed bus defined by a non-zero average value voltage that is proportional to a rectified utility grid AC supply voltage. The PV energy system also includes a plurality of PV modules, each PV module including a bucking circuit configured to convert a corresponding PV voltage into a pulsing current, wherein the pulsating bus is configured to sum the pulsing currents produced via the plurality of PV modules such that a resultant pulsing current is injected into the pulsating bus in phase with the non-zero average value voltage. A current unfolding circuit is configured to control the amount of AC current injected into the utility grid in response to the resultant pulsing current.

Abstract: A power curtailment system is electrically coupled to a power converter and configured to control the power converter to adjust output power of the power converter in response to a power curtailment requirement condition. The power curtailment system includes at least one sensor configured to measure at least one environmental factor in an environment of the power converter over time. The power curtailment system further includes a controller configured to adjust a power curve over time based on the at least one environmental factor and, upon the power curtailment requirement condition, control the power converter to provide an adjusted output power based on data from the power curve and the power curtailment requirement condition.

Abstract: An electric vehicle charging station is described. The charging station includes an input connector configured for coupling with an alternating current (AC) power source and an output connector configured for coupling with an electric vehicle. The charging station also includes a variable-output transformer comprising a primary side and a secondary side. The primary side is coupled to the input connector and the secondary side is coupled to the output connector and configured to be in selective electromagnetic communication with an energy storage device associated with the electric vehicle. The charging station also includes a controller coupled to the transformer and configured to determine a level of voltage to provide to the electric vehicle.

Abstract: A substrate layer for use in an inductor is provided. The substrate layer comprises traces disposed on a first side of the substrate layer, wherein the traces are configured to facilitate conduction of current in a winding of the inductor, a sealing layer disposed on a second side of the substrate layer, wherein the sealing layer is configured to provide a sealing border for an electrically isolated cooling channel and an interconnect foil disposed on the second side of the substrate layer, wherein the interconnect foil is configured to facilitate operationally coupling the substrate layer to a second substrate layer. Further, the first substrate layer and the second substrate layer may be operationally coupled to form a winding for use in an inductor with an electrically isolated cooling channel in between.

Abstract: A method to clamp an open circuit voltage in a photovoltaic module is proposed. The method include coupling a load resistor across an inverter module, initiating the inverter module and loading the inverter module via the load resistor, and coupling the loaded inverter module to the photovoltaic module. The method further include dissipating power via the load resistor to clamp the open circuit voltage of the photovoltaic module, synchronizing an output voltage of the inverter module with a voltage of a grid and then coupling the inverter module to the grid and de-coupling the load resistor across the inverter module.

Abstract: A method of operating a three level converter includes controlling the output voltage of the converter when a DC link voltage of the three level converter is lower than one-half of a rated DC link voltage of the converter by, for each leg of the converter, alternately connecting an output terminal of the leg to the positive terminal or the negative terminal of the DC link. When the DC link voltage is at least one-half of the rated DC link voltage, the method includes controlling the output voltage of the converter by, for each leg, selectively connecting the output terminal of the converter to the positive terminal, the negative terminal, or a mid-point of the DC link.

Abstract: A power inverter system includes a plurality of power semiconductor switching devices. Each switching device includes a corresponding gate turn off resistance configured to increase during starting up periods of the inverter system such that the open circuit voltage of a corresponding power source providing power to the power inverter system does not exceed the switching device blocking voltage ratings during the corresponding switching turn-off periods. The starting up period is the time required to bring the corresponding power source voltage from its open circuit voltage level to a predetermined voltage which constitutes a safe operating condition for the plurality of power semiconductor switching devices.

Abstract: A power inverter system includes a DC to AC inverter configured to convert DC voltage from a DC power source to AC voltage. A DC link couples the DC power source and the inverter. An inverter pre-charger operates to pre-charge the inverter to achieve a desired DC link voltage prior to connecting the power inverter system to an AC power grid. A phased lock loop synchronizes the pre-charged inverter to the AC power grid prior to connecting the power inverter system to the AC power grid. The pre-charged inverter regulates the DC link voltage to about the minimum voltage level that allows control of AC grid currents via the inverter subsequent to connecting the power inverter system to the AC grid. The inverter operates in a maximum power point tracking control mode only subsequent to a first voltage transient caused by connecting the DC power source to energize the power inverter system.

Abstract: A power generation system includes integrated photovoltaic (PV) panels. Each of the integrated PV panel includes photovoltaic cells, a junction coupler coupling the photovoltaic cells in series, in parallel, or in combinations thereof, output terminals, and a DC to AC converter coupled between the junction coupler and the output terminals. The DC to AC converter includes switching devices and the integrated PV panels are coupled in series at the respective output terminals. A controller is provided in the power generation system for generation switching command signals for the switching devices of the integrated PV panels to synthesize an output voltage of the power generation system.

Abstract: A photovoltaic (PV) plant power curve measurement system determines normalized irradiation data in response to algorithmic software based on measured or calculated irradiance at one or more desired PV plant locations. The measurement system also measures PV plant electrical power and generates an estimated power curve map of corresponding photovoltaic plant electrical power as a function of the normalized irradiation data and the measured PV plant electrical power, such that corresponding power curve data can be compared to historical, theoretical or simulated power curve data based on normalized irradiation data for the photovoltaic plant to detect degradation of the photovoltaic plant in a desired time frame.

Abstract: A DC transmission system for solar arrays comprises a system DC link for receiving power from the solar arrays through series coupled DC to DC converter. DC to AC power converter modules are coupled in series between the system DC link and a power grid.

Abstract: In accordance with the present disclosure, a power management system is provided that includes a control system to monitor the actual power output of one or more arrays of photovoltaic modules. The power management system includes a processor-based device to estimate the power output of the one or more arrays of photovoltaic modules and to compare the estimated power output to the actual power output measurement received from the control system. A method is provided for monitoring power generation. A method is provided for generating a model to estimate power generation.

Abstract: A method to clamp an open circuit voltage in a photovoltaic module is proposed. The method include coupling a load resistor across an inverter module, initiating the inverter module and loading the inverter module via the load resistor, and coupling the loaded inverter module to the photovoltaic module. The method further include dissipating power via the load resistor to clamp the open circuit voltage of the photovoltaic module, synchronizing an output voltage of the inverter module with a voltage of a grid and then coupling the inverter module to the grid and de-coupling the load resistor across the inverter module.

Abstract: A method of operating a three level converter includes controlling the output voltage of the converter when a DC link voltage of the three level converter is lower than one-half of a rated DC link voltage of the converter by, for each leg of the converter, alternately connecting an output terminal of the leg to the positive terminal or the negative terminal of the DC link. When the DC link voltage is at least one-half of the rated DC link voltage, the method includes controlling the output voltage of the converter by, for each leg, selectively connecting the output terminal of the converter to the positive terminal, the negative terminal, or a mid-point of the DC link.

Abstract: A substrate layer for use in an inductor is provided. The substrate layer comprises traces disposed on a first side of the substrate layer, wherein the traces are configured to facilitate conduction of current in a winding of the inductor, a sealing layer disposed on a second side of the substrate layer, wherein the sealing layer is configured to provide a sealing border for an electrically isolated cooling channel and an interconnect foil disposed on the second side of the substrate layer, wherein the interconnect foil is configured to facilitate operationally coupling the substrate layer to a second substrate layer. Further, the first substrate layer and the second substrate layer may be operationally coupled to form a winding for use in an inductor with an electrically isolated cooling channel in between.

Abstract: A photovoltaic (PV) energy system includes a pulsed bus defined by a non-zero average value voltage that is proportional to a rectified utility grid AC supply voltage. The PV energy system also includes a plurality of PV modules, each PV module including a bucking circuit configured to convert a corresponding PV voltage into a pulsing current, wherein the pulsating bus is configured to sum the pulsing currents produced via the plurality of PV modules such that a resultant pulsing current is injected into the pulsating bus in phase with the non-zero average value voltage. A current unfolding circuit is configured to control the amount of AC current injected into the utility grid in response to the resultant pulsing current.