Abstract: A propulsion system comprising an electric drive, a DC link electrically coupled to the electric drive, and a first energy storage system electrically coupled to the electric drive, the first energy storage system comprising at least a high specific-power energy storage device is shown. The propulsion system further includes a second energy storage system, wherein a first terminal of the second energy storage system is electrically coupled to the electric drive through the DC link and a second terminal of the second energy storage system is coupled in series with a terminal of the high specific-power energy storage device. A multi-channel bi-directional boost converter is coupled to the first energy storage system and to the second energy storage system, wherein the connection between the terminal of the high specific-power energy storage device and the second terminal of the second energy storage system bypasses the multi-channel bi-directional boost converter.

Abstract: A propulsion system includes an electric drive, a first energy storage system electrically coupled to the electric drive through a DC link, and a second energy storage system electrically coupled to the first energy storage system in a series connection. The first energy storage system comprises a high specific-energy storage device and the second energy storage system comprises a low specific-power storage device. The propulsion system also includes a third energy storage system comprising a high specific-energy storage device electrically coupled to the second energy storage system. A bi-directional boost converter is electrically coupled to the second and third energy storage systems such that a terminal of the third energy storage system is electrically coupled to a low voltage side of the bi-directional boost converter and a terminal of the second energy storage system is coupled to a high voltage side of the bi-directional boost converter.

Abstract: An electrical generator includes a stator having fractional-slot concentrated windings and a rotor having field windings. A drive is provided having a circuit to control current flow to the field windings and a controller to input an initial DC field current demand to the circuit to cause the circuit to output an initial DC field current representative of a DC field current demand that would cause an electrical generator having sinusoidal stator windings to output a desired AC power. The controller receives feedback on the magnetic field generated by the initial DC field current, isolates an ideal fundamental component of the magnetic field based on the feedback and to generate a modified DC field current demand, and inputs the modified DC field current demand to the circuit, thereby causing the circuit to output an instantaneous non-sinusoidal current to the field windings to generate a sinusoidal rotating air gap magnetic field.

Abstract: A propulsion system includes an electric drive, a first energy storage system electrically coupled to the electric drive through a DC link, and a second energy storage system electrically coupled to the first energy storage system in a series connection. The first energy storage system comprises a high specific-energy storage device; the second energy storage system comprises a high specific-power storage device. The propulsion system also includes a bi-directional boost converter electrically coupled to the first and second energy storage systems such that a terminal of the first energy storage system is electrically coupled to a low voltage side of the bi-directional boost converter and a first terminal of the second energy storage system is coupled to a high voltage side of the bi-directional boost converter. The series connection bypasses the bi-directional boost converter.

Abstract: An energy storage and management system (ESMS) includes one or more energy storage devices configured to store electrical energy, a power electronic conversion system having a plurality of energy ports and including a plurality of DC electrical converters, and a controller configured to split a source current flowing from an electrical source that is connected to one of the plurality of energy ports into a first current and a second current, wherein the first and second currents flows respectively first and second of the plurality of DC converters, alter the first current and the second current by selectively turning on and turning off current flow to the first and second DC converters, and form a charging current by passing the first current and the second current simultaneously to a first of the one or more energy storage devices that is coupled to a second of the plurality of energy ports.

Abstract: A method of operating a vehicle having an electric drive is provided. The method includes defining a first zone and a second zone. The first zone has an associated first characteristic and the second zone has an associated second characteristic that differs from the first characteristic. The method further includes switching an operating mode of a vehicle from a first operating mode in the first zone to a second operating mode in the second zone in response to the vehicle translating from the first zone to the second zone. Associated vehicles and systems are provided also.

Abstract: An apparatus comprises a power electronic energy conversion system comprising a first energy storage device configured to store DC energy and a first voltage converter configured to convert a second voltage from a remote power supply into a first charging voltage configured to charge the first energy storage device. The apparatus also includes a first controller configured to control the first voltage converter to convert the second voltage into the first charging voltage and to provide the first charging voltage to the first energy storage device during a charging mode of operation and communicate with a second controller located remotely from the power electronic energy conversion system to cause a second charging voltage to be provided to the first energy storage device during the charging mode of operation to rapidly charge the first energy storage device.

Abstract: A propulsion system is provided that includes an energy system, an auxiliary system, and a system controller. The energy system includes a bi-directional boost converter coupled to a direct current (DC) link and comprising a plurality of input channels. The energy system also includes a first energy storage device coupled to a first input channel of the bi-directional boost converter via a DC bus. The auxiliary system is coupled to the energy system and includes an auxiliary energy source, an auxiliary load, and an auxiliary load controller coupled to the auxiliary energy source and to the auxiliary load. The system controller is configured to cause the auxiliary load controller to reduce a power draw of the auxiliary load from the auxiliary energy source and to cause the bi-directional boost converter to boost a voltage supplied by the auxiliary energy source and to supply the boosted voltage to the DC link.

Abstract: A fraction inverter circuit includes a first energy storage device configured to output a DC voltage, a first bi-directional DC-to-AC voltage inverter coupled to the first energy storage device, and a first electromechanical device. The first electromechanical device includes a first plurality of conductors coupled to the first bi-directional DC-to-AC voltage inverter, a second plurality of conductors coupled together, and a plurality of windings coupled between the first plurality of conductors and the second plurality of conductors. The traction converter circuit also includes a charge bus comprising a first conductor coupled to the second plurality of conductors of the first electromechanical device, the charge bus configured to transmit a charging current to or receive a charging current from the first electromechanical device to charge the first energy storage device via the first electromechanical device and the first bi-directional DC-to-AC voltage inverter.

Abstract: An apparatus comprises a power electronic energy conversion system comprising a first energy storage device configured to store DC energy and a first voltage converter configured to convert a second voltage from a remote power supply into a first charging voltage configured to charge the first energy storage device. The apparatus also includes a first controller configured to control the first voltage converter to convert the second voltage into the first charging voltage and to provide the first charging voltage to the first energy storage device during a charging mode of operation and communicate with a second controller located remotely from the power electronic energy conversion system to cause a second charging voltage to be provided to the first energy storage device during the charging mode of operation to rapidly charge the first energy storage device.

Abstract: A system and method for a propulsion system includes an electric motor and an energy storage unit configured to supply a primary power to the electric motor. The propulsion system also includes a plurality of auxiliary power units (APUs) configured to supply a secondary power to at least one of the electric motor and the energy storage unit. Each of the plurality of APUs includes a free-piston engine configured to generate a mechanical output, a linear generator configured to transform the mechanical output to an electrical power, and a controller. The controller receives a power command from the electric motor and/or the energy storage unit, determines an amount of secondary power needed to meet the power command, and selectively activates a number of the plurality of APUs to generate the needed amount of secondary power.

Abstract: A fraction inverter circuit includes a first energy storage device configured to output a DC voltage, a first bi-directional DC-to-AC voltage inverter coupled to the first energy storage device, and a first electromechanical device. The first electromechanical device includes a first plurality of conductors coupled to the first bi-directional DC-to-AC voltage inverter, a second plurality of conductors coupled together, and a plurality of windings coupled between the first plurality of conductors and the second plurality of conductors. The traction converter circuit also includes a charge bus comprising a first conductor coupled to the second plurality of conductors of the first electromechanical device, the charge bus configured to transmit a charging current to or receive a charging current from the first electromechanical device to charge the first energy storage device via the first electromechanical device and the first bi-directional DC-to-AC voltage inverter.

Abstract: A system for transferring energy from an energy source includes a first energy source, a DC link coupled to a DC load, a first DC-to-DC voltage converter coupled to the DC link, and a second DC-to-DC voltage converter coupled to the first energy source. A controller is coupled to the first and second DC-to-DC voltage converters and configured to determine a voltage level of the first energy source and of the DC link. If the voltage level of the DC link is less than the voltage level of the first energy source, the controller controls the second DC-to-DC voltage converter to draw energy from the first energy source to cause the DC voltage output from the first energy source and supplied to the first DC-to-DC voltage converter to be below the DC load voltage supplied to the DC link via the first DC-to-DC voltage converter.

Abstract: A contactor unit includes an input lead connectable to a first lead of an energy output device, an output lead connectable to a first lead of a voltage bus, a contactor that connects and disconnects the input lead from the output lead, a driver configured to operate the contactor, a serial data link connectable to a system controller that is external to the contactor unit, and an integrated circuit (IC) positioned within the contactor unit and configured to output a control command to the driver to open the contactor based on at least one of a current in either the input lead or the output lead and a voltage differential across the contactor, and output a contactor control status via the serial data link.

Abstract: An electric vehicle includes a controller configured to receive sensor feedback from a high voltage storage device and from a low voltage storage device, compare the sensor feedback to operating limits of the respective high and low voltage storage device, determine, based on the comparison a total charging current to the high voltage storage device and to the low voltage storage device and a power split factor of the total charging current to the high voltage device and to the low voltage device, and regulate the total power to the low voltage storage device and the high voltage storage device based on the determination.

Abstract: A transformer tap-changing circuit comprises an apparatus that includes a transformer comprising a secondary winding configured to inductively couple to a primary winding when a current is passed through the primary winding from an energy source, a first rectifier coupled to the secondary winding and configured to rectify a first AC voltage from the secondary winding into a first DC voltage, and a second rectifier coupled to the secondary winding and configured to rectify a second AC voltage from the secondary winding into a second DC voltage. The apparatus also includes a DC bus coupled to the first and second rectifiers and configured to receive the first and second DC voltages therefrom, wherein the first AC voltage is higher than the second AC voltage, and wherein the first DC voltage is higher than the second DC voltage.

Abstract: A system and method of manufacturing an electric machine comprising a rotor and a stator, wherein the stator comprises a fractional-slot concentrated winding having two sets of terminals, wherein a first set of terminals configures the fractional-slot concentrated winding to have a first pole-number (P1), and wherein a second set of terminals configures the fractional-slot concentrated winding to have a second pole number (P2) different from the first pole-number (P1).

Abstract: A drive circuit comprising a DC bus configured to supply power to a load, a first fuel cell coupled to the DC bus and configured to provide a first power output to the DC bus, and a second fuel cell coupled to the DC bus and configured to provide a second power output to the DC bus supplemental to the first fuel cell. The drive circuit further includes an energy storage device coupled to the DC bus and configured to receive energy from the DC bus when a combined output of the first and second fuel cells is greater than a power demand from a load, and provide energy to the DC bus when the combined output of the first and second fuel cells is less than the power demand from the load.

Abstract: An apparatus for transferring energy using onboard power electronics comprises a first energy storage device configured to output a DC voltage and a DC bus coupled to the first energy storage device, the DC bus coupleable to a high-impedance voltage source. The apparatus also comprises a braking resistor coupled to the DC bus and to a control circuit, and a controller. The controller is configured to control the control circuit to cause on the DC bus to be dissipated through the braking resistor during a regenerative braking event, cause the first energy storage device to receive a charging energy from the high-impedance voltage source through the braking resistor during a charging event, and after a threshold value has been crossed, cause the first energy storage device to receive the charging energy from the high-impedance voltage source bypassing the braking resistor during the charging event.

Abstract: A wet masking system for applying a maskant to a portion of a workpiece includes one or more pressurized mixing vessels with agitators for continuously blending the ingredients of the maskant, a dispensing system connected to the vessels for supplying metered volumes of maskant to injection valves. An electronic controller operable for controlling the system to coat the portion. A fixture for holding the workpiece with just the portion inside a cavity of the fixture includes one or more inlet ports alignable with injection ports of the injection valves injecting the maskant into the cavity. Heaters are positioned for drying or flash drying the maskant on the portion of the workpiece. Recirculation lines from the injection valves to at least one of the mixing vessels operated by the controller to flow the maskant through the recirculation lines after a period of time when no maskant is flowing through masking system.