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 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 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 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 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 system for the transmission of a direct current (DC) at a medium voltage level includes a system DC link configured to carry power from a source to a load module. The load module includes a DC-to-DC voltage step-down converter, a DC-to-AC inverter coupled downstream to the DC-to-DC voltage step-down converter, and a system AC link for carrying power from the load module to a motor system on a load side of the system AC link. The system is effective for delivering power over distances that are greater than 30 kilometers, and for delivery of power from an on-shore to offshore and sub-sea 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 power generation system including a plurality of isolated power converters and a plurality of first weatherable units is provided. Each of the isolated power converters includes a primary stage, a secondary stage and a transformer providing an electrically contactless connection between the primary and secondary stages. The first weatherable unit includes a photovoltaic module coupled to the primary stage of a respective one of the plurality of isolated power converters and a primary side of the transformer. The system further includes a plurality of second units, each having a second side of the transformer coupled to the secondary stage of a respective one of the plurality of isolated power converters. The system also includes a direct current (DC) to alternating current (AC) inverter and a connection unit for coupling the secondary stages of the isolated power converter and the DC to AC inverter. The DC to AC inverter is configured to transfer power from the photovoltaic module to a power grid.

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 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 circuit and system topology includes a plurality of controller units configured to provide a high reliability power system. Sub-systems and devices are controlled via the plurality of controller units such that the high reliability power system remains functional, even subsequent to controller unit, sub-system and device failures.

Abstract: A protective circuit for a multi-level converter including a DC link capacitor bank includes: an energy absorbing element; switches, wherein at least two of the switches each couple the energy absorbing element to the capacitor bank; and a controller configured to provide control signals to the switches to selectively actuate the switches to enable control of energy dissipation and to enable control of voltage balance on the capacitor bank of the multi-level converter.

Abstract: A device includes at least one semiconductor switching circuit connected to a power source and a load and at least one breaker switch integrated with the at least one semiconductor switching circuit. The breaker circuit may be connected in series with the at least one semiconductor switching circuit and the at least one breaker switch is configured to create an open circuit in less than about twenty microseconds of receipt of a predetermined threshold of semiconductor switch current to thereby prevent damage to the at least one semiconductor switching circuit or housing. A method of preventing damage to a semiconductor switching circuit or device is also presented.

Abstract: A system for damping audible noise from a drive train. One embodiment is a system with an audible noise signal from a drive train wherein a damping circuit produces a damping torque that is a phase shifted and amplified version of the noise signal that is applied to the air-gap torque of a generator or motor coupled to the drive train and effectively reduces the audible noise.

Abstract: A system for the transmission of a direct current (DC) at a medium voltage level includes a system DC link configured to carry power from a source to a load module. The load module includes a DC-to-DC voltage step-down converter, a DC-to-AC inverter coupled downstream to the DC-to-DC voltage step-down converter, and a system AC link for carrying power from the load module to a motor system on a load side of the system AC link. The system is effective for delivering power over distances that are greater than 30 kilometers, and for delivery of power from an on-shore to offshore and sub-sea load.

Abstract: An integrated thermal management system is provided. The system includes a first device configured to release a first heat loss and coupled to an integrated cooling system. The system also includes at least a second device configured to release a second heat loss and coupled to the integrated cooling system. The system also includes at least one heat exchanger configured to release the first heat loss and the second heat loss to ambient.

Abstract: A protective circuit for a multi-level converter including a DC link capacitor bank includes: an energy absorbing element; switches, wherein at least two of the switches each couple the energy absorbing element to the capacitor bank; and a controller configured to provide control signals to the switches to selectively actuate the switches to enable control of energy dissipation and to enable control of voltage balance on the capacitor bank of the multi-level converter.

Abstract: A system includes an energy source configured for operating as a current limited source and a DC-to-DC converter or current switched inverter configured to receive current from the energy source and comprising a normally-on switch.

Abstract: A hybrid locomotive includes at least one traction motor coupled to at least one of a plurality of axles and configured to drive at least one axle. A power converter is coupled to a main engine and to at least one traction motor and configured to supply electrical energy to the at least one traction motor and a secondary energy storage unit. A fuel storage unit is coupled to the main engine and configured to supply a gaseous fuel to the main engine. The main engine is adapted to burn gaseous fuel for reduced emissions, while maintaining excellent power output characteristics, that may be supplemented by secondary power sources.