Abstract: A multilevel converter includes a plurality of phase legs each having at least two inner switching devices, at least two outer switching devices, at least two clamping diodes, a split DC link and a switching device failure detection circuit. The switching device failure detection circuit includes a logic module for each of the switching devices, a voltage calculation module and a failure detection algorithm. The logic module generates a blocking state logic signal by comparing a switching device voltage and a threshold reference voltage and the voltage calculation module determines an expected voltage blocking state for each of the switching devices based on the gate drive signals of the switching devices and an output current direction. The failure detection algorithm detects a failure condition in any of the switching devices based on the blocking state logic signals and the expected voltage blocking states of the switching devices.

Abstract: A contactless power transfer device for transferring electrical power from a nacelle to a hub of a wind turbine is provided. The power transfer device includes power input terminals arranged at the nacelle for inputting electrical input power and power output terminals arranged at the hub for outputting electrical output power. A wound rotor radial flux electrical machine is provided which has at least one stationary winding electrically connected to the power input terminals and arranged at a stationary component coupled to the nacelle, and at least one rotatable winding electrically connected to the power output terminals and arranged at a rotatable component coupled to the hub, for converting the electrical input power into the electrical output power.

Abstract: A control system for a multilevel converter includes a differential mode current regulator, a neutral point (NP) controller and a PWM controller for generating switching pulses for the multilevel converter. The differential mode current regulator generates reference voltage command signals based on a difference between reference current command signals and actual current command signals, and the NP controller determines a modified neutral point current signal in response to a DC link voltage unbalance. The NP controller utilizes the modified neutral point current signal to generate a common mode reference voltage signal. The switching pulses are generated by the PWM controller based on the reference voltage command signals and the common mode reference voltage signal.

Abstract: A three level neutral point clamped (NPC) converter includes a plurality of phase legs each having at least two inner switching devices, at least two outer switching devices, at least two clamping diodes, and a protection circuit. An inner component failure sensing circuit is employed in the protection circuit to detect a failure condition in any of the inner switching devices or clamping diodes. The protection circuit further includes a gating signal generation circuit configured to generate a turn ON signal for a respective outer switching device that is adjacent to the failed inner switching device or the clamping diode.

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 direct current (DC) power transmission system is described. The DC power transmission system includes a first plurality of series connected power collection systems and at least one superconducting DC conductor coupled to the plurality of series connected power collection systems and configured to transmit power generated by the plurality of power collection systems to a remote load.

Abstract: A lightning protection system for a wind turbine blade or aircraft wing includes a glass-reinforced fiber or carbon-reinforced wind turbine blade or aircraft wing having a tip region, a suction side, a pressure side, a leading edge and a trailing edge. A substantially planar sheet of conductive or semi-conductive material is disposed internal to the blade tip region or wing tip region and between the suction side and pressure side. The sheet operates during a lightning discharge to form an electric field control mechanism causing the lightning discharge to attach to the tip region. The sheet is in electrical communication or galvanic connection with a conductive or semi-conductive path such that the electric field control mechanism and the path together operate to protect the wind turbine blade or aircraft wing from damage caused by the lightning strike in the tip region of the wind turbine blade or aircraft wing by controlling an electric field in the tip region caused by the lightning strike.

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 of operating a neutral point clamped (NPC) three level converter is provided. The NPC converter includes at least two legs, each leg comprising first and second top switches connected in series at a first mid point. The converter further includes first and second bottom switches connected in series at a second mid point, and first and second middle switches connected in series at a third mid point therebetween. The first top and second bottom switches are connected in series at a DC link and the first and the second middle switches are connected between the first and the second mid points. Each of the top, bottom and middle switches has an antiparallel diode thereacross. The method includes alternately switching the first and second top switches to ON state when the first middle switch is in ON state and the second middle switch is in OFF state.

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 compact transformer-power converter assembly includes: a transformer immersed in oil and a cooling fluid path through a power converter system for extracting heat from the power converter system and the oil.

Abstract: A vehicle includes a power connector configured to mate with an electrical power grid receptacle and receive a grid power therefrom and a heating and cooling system electrically connected to the power connector to receive grid power therefrom and configured to modify a temperature the vehicle cabin. The vehicle also includes a temperature control loop configured to selectively activate and control the heating and cooling system and a controller configured to receive a first input signal comprising a desired vehicle activation time and a second input signal comprising a starting vehicle cabin temperature and a desired vehicle cabin temperature. The controller determines a temperature control loop activation time based on the first and second input signals that is prior to the desired vehicle activation time and transmits an activation signal to the temperature control loop at the temperature control loop activation time to activate the heating and cooling system.

Abstract: A direct current (DC) power transmission system is described. The DC power transmission system includes a first plurality of series connected power collection systems and at least one superconducting DC conductor coupled to the plurality of series connected power collection systems and configured to transmit power generated by the plurality of power collection systems to a remote load.

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: Embodiments presented herein are directed to a system comprising, a semiconductor device including a semiconductor junction, an optical fiber, a proximal end of said optical fiber in electromagnetic communication with said semiconductor junction, and a processing unit in electromagnetic communication with a distal end of said optical fiber, said processing unit capable of receiving electromagnetic information available at said distal end and processing the electromagnetic information.

Abstract: A three level neutral point clamped (NPC) converter includes a plurality of phase legs each having at least two inner switching devices, at least two outer switching devices, at least two clamping diodes, and a protection circuit. An inner component failure sensing circuit is employed in the protection circuit to detect a failure condition in any of the inner switching devices or clamping diodes. The protection circuit further includes a gating signal generation circuit configured to generate a turn ON signal for a respective outer switching device that is adjacent to the failed inner switching device or the clamping diode.

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.