Abstract: According to some embodiments, a traction system is disclosed. The traction system includes a DC bus, an energy storage device coupled to the DC bus, and a voltage converter assembly coupled to the energy storage device. The voltage converter assembly includes a plurality of phase legs. The traction system further includes an electromechanical device including a plurality of windings coupled to the voltage converter assembly. The traction system also includes a switch coupled to the DC bus between the voltage converter assembly and the energy storage device. The traction system includes a controller configured to control the switch and the voltage converter assembly such that a phase leg and a winding of the electromechanical device form a DC/DC converter.

Abstract: A DC charging circuit for an electric vehicle includes a neutral-point clamped (NPC) rectifier and a DC/DC buck converter. The NPC rectifier is configured to convert three-phase AC power to a first DC voltage at a rectifier output stage. The DC/DC buck converter includes a first DC stage coupled to the rectifier output stage, and a second DC stage configured to be coupled to the electric vehicle. The DC/DC buck converter is configured to convert the first DC voltage to a second DC voltage to be supplied to the electric vehicle.

Abstract: A system and method for operating a drive system coupleable to one or more DC and AC electrical ports is disclosed. The drive system includes a DC link, at least one DC-DC converter, at least one DC-AC converter, a DC link capacitor, and a control system configured to control operation of one or more of the at least one DC-DC converter and the at least one DC-AC converter relative to one another based on operational parameters thereof. In controlling operation of one or more of the at least one DC-DC converter and the at least one DC-AC converter, the control system controls at least one of a switching frequency of the at least one DC-DC converter, a switching frequency of the at least one DC-AC converter, a DC-DC converter carrier signal phase, a DC-AC converter carrier signal phase, and a duty cycle of the at least one DC-DC converter.

Abstract: A system and method for operating a drive system coupleable to one or more DC and AC electrical ports is disclosed. The drive system includes a DC link, at least one DC-DC converter, at least one DC-AC converter, a DC link capacitor, and a control system configured to control operation of one or more of the at least one DC-DC converter and the at least one DC-AC converter relative to one another based on operational parameters thereof. In controlling operation of one or more of the at least one DC-DC converter and the at least one DC-AC converter, the control system controls at least one of a switching frequency of the at least one DC-DC converter, a switching frequency of the at least one DC-AC converter, a DC-DC converter carrier signal phase, a DC-AC converter carrier signal phase, and a duty cycle of the at least one DC-DC converter.

Abstract: A hybrid energy system for providing power to a load and for providing a fast variation of DC link voltage to improve system efficiency is disclosed. The system includes a load, a direct current (DC) link electrically coupled to the load, an energy storage system having a first energy storage device and a second energy storage device arranged in series, and a bi-directional DC-DC converter electrically coupled to the DC link and to the energy storage system, the bi-directional DC-DC converter being connected to a node located between the first energy storage device and the second energy storage device and to a node connecting the second energy storage device to the DC link.

Abstract: A method of controlling an electric motor assembly includes detecting a backspin event of an electric motor, and managing a response to the detected backspin event of the electric motor. The backspin event of the electric motor is detected based at least in part on feedback from a sensor configured to measure a current or a voltage on a cable coupled to the electric motor. The response includes communicating an alert to personnel, controlling the voltage on the cable to be less than a voltage threshold, or any combination thereof.

Abstract: A method includes controlling a first power output to an electric machine during a transient event. Controlling the first power output includes measuring values of the first power output provided to the electric machine during the transient event, receiving an estimated speed input of the electric machine, determining adjustment commands to compensate the first power output for the transient event of the electric machine, generating switch commands for gate drives of a variable frequency drive (VFD) based at least in part on the adjustment commands, and modifying the first power output during the transient event based on the switch commands.

Abstract: A system and method for position sensorless control of an AC electric machine is disclosed. A drive system for driving an AC electric machine provides a primary current excitation to drive the AC electric machine, the primary current excitation comprising a current vector having a magnitude and angle. The drive system injects a carrier signal to the AC electric machine that is superimposed onto the current vector, with the carrier signal generating a carrier response signal responsive to the injected carrier signal. The drive system measures at least one magnetic alignment signature of the AC electric machine from the generated carrier response signal and controls an orientation of the current vector using the measured at least one magnetic alignment signature to operate the AC electric machine.

Abstract: The DC leakage current detector for detecting leakage current in a DC bus includes a pair of transformers each comprising a magnetic core and excitation and detection windings would about the magnetic core, with the magnetic core positionable about a pair of conductors that create a magnetic field that is a sum of currents in the conductors. An excitation and biasing circuit is connected to the excitation winding in each transformer to inject a current signal thereto that creates a changing magnetic flux in the core of each transformer and a detector output connected to the detection winding in each transformer to receive a voltage therefrom generated responsive to the magnetic flux in the core of each transformer, wherein the voltage on the detection windings provides a net voltage at the detector output whose value is indicative of a presence of a leakage current on the DC bus.

Abstract: A system and method for leakage current detection and fault location identification in a DC power circuit is disclosed. The system includes a plurality of DC leakage current detectors positioned throughout the DC power circuit, the DC leakage current detectors configured to sense and locate a leakage current fault in the DC power circuit. Each of the DC leakage current detectors is configured to generate a net voltage at an output thereof indicative of whether a leakage current fault is present at a location at which the respective DC leakage current detector is positioned. A logic device in operable communication with the DC leakage current detectors receives output signals from each DC leakage current detector comprising the net voltage output and locates the leakage current fault in the DC power circuit based on the output signals received from the plurality of DC leakage current detectors.

Abstract: A method includes controlling a first power output to an electric machine during a transient event. Controlling the first power output includes measuring values of the first power output provided to the electric machine during the transient event, receiving an estimated speed input of the electric machine, determining adjustment commands to compensate the first power output for the transient event of the electric machine, generating switch commands for gate drives of a variable frequency drive (VFD) based at least in part on the adjustment commands, and modifying the first power output during the transient event based on the switch commands.

Abstract: A system and method for operating a drive system coupleable to one or more DC and AC electrical ports is disclosed. The drive system includes a DC link, at least one DC-DC converter, at least one DC-AC converter, a DC link capacitor, and a control system configured to control operation of one or more of the at least one DC-DC converter and the at least one DC-AC converter relative to one another based on operational parameters thereof. In controlling operation of one or more of the at least one DC-DC converter and the at least one DC-AC converter, the control system controls at least one of a switching frequency of the at least one DC-DC converter, a switching frequency of the at least one DC-AC converter, a DC-DC converter carrier signal phase, a DC-AC converter carrier signal phase, and a duty cycle of the at least one DC-DC converter.

Abstract: Systems and methods are provided for a soft switching topology for a direct current (DC)-DC converter. The systems and methods determine an operational status of an electric motor, and activate at least one of an upper or lower first or second semiconductor switches based on an operation of the electric motor. The first and second switching circuits are conductively coupled to a power inverter circuit. The systems and methods include deliver an adjusted voltage to one of the power inverter circuit or a power circuit based on the operational status of the electric motor.

Abstract: A system and method for leakage current detection and fault location identification in a DC power circuit is disclosed. The system includes a plurality of DC leakage current detectors positioned throughout the DC power circuit, the DC leakage current detectors configured to sense and locate a leakage current fault in the DC power circuit. Each of the DC leakage current detectors is configured to generate a net voltage at an output thereof indicative of whether a leakage current fault is present at a location at which the respective DC leakage current detector is positioned. A logic device in operable communication with the DC leakage current detectors receives output signals from each DC leakage current detector comprising the net voltage output and locates the leakage current fault in the DC power circuit based on the output signals received from the plurality of DC leakage current detectors.

Abstract: The DC leakage current detector for detecting leakage current in a DC bus includes a pair of transformers each comprising a magnetic core and excitation and detection windings would about the magnetic core, with the magnetic core positionable about a pair of conductors that create a magnetic field that is a sum of currents in the conductors. An excitation and biasing circuit is connected to the excitation winding in each transformer to inject a current signal thereto that creates a changing magnetic flux in the core of each transformer and a detector output connected to the detection winding in each transformer to receive a voltage therefrom generated responsive to the magnetic flux in the core of each transformer, wherein the voltage on the detection windings provides a net voltage at the detector output whose value is indicative of a presence of a leakage current on the DC bus.

Abstract: A system and method for heating ferrite permanent magnets in an electrical machine is disclosed. The permanent magnet machine includes a stator assembly and a rotor assembly, with a plurality of ferrite permanent magnets disposed within the stator assembly or the rotor assembly to generate a magnetic field that interacts with a stator magnetic field to produce a torque. A controller of the electrical machine is programmed to cause a primary field current to be applied to the stator windings to generate the stator magnetic field, so as to cause the rotor assembly to rotate relative to the stator assembly. The controller is further programmed to cause a secondary current to be applied to the stator windings to selectively generate a secondary magnetic field, the secondary magnetic field inducing eddy currents in at least one of the stator assembly and the rotor assembly to heat the ferrite permanent magnets.

Abstract: According to some embodiments, an electronic drive circuit is disclosed. The electronic drive circuit includes an energy storage device and a first bridge circuit coupled to the energy storage device. The first bridge circuit includes at least one leg having two switches. The electronic drive circuit also includes a transformer. The transformer includes a first winding coupled to the first bridge circuit and a second winding coupled to the energy storage device through a center tap. The electronic drive circuit further includes a second bridge circuit coupled to the second winding of the transformer. The second bridge circuit includes a pair of switches operable to conduct in both directions and block voltage in both directions.

Abstract: A system and method for position sensorless control of an AC electric machine is disclosed. A drive system for driving an AC electric machine provides a primary current excitation to drive the AC electric machine, the primary current excitation comprising a current vector having a magnitude and angle. The drive system injects a carrier signal to the AC electric machine that is superimposed onto the current vector, with the carrier signal being selected to generate a carrier response signal that has sensitivity to magnetic alignment information of the AC electric machine at its operating point. The drive system measures at least one magnetic alignment signature of the AC electric machine from the generated carrier response signal and controls an orientation of the current vector using the measured at least one magnetic alignment signature, so as to achieve a desired magnetic operation of the AC electric machine.

Abstract: A system and method for position sensorless control of an AC electric machine is disclosed. A drive system for driving an AC electric machine provides a primary current excitation to drive the AC electric machine, the primary current excitation comprising a current vector having a magnitude and angle. The drive system injects a carrier signal to the AC electric machine that is superimposed onto the current vector, with the carrier signal generating a carrier response signal responsive to the injected carrier signal. The drive system measures at least one magnetic alignment signature of the AC electric machine from the generated carrier response signal and controls an orientation of the current vector using the measured at least one magnetic alignment signature to operate the AC electric machine.

Abstract: A system and method for position sensorless control of an AC electric machine is disclosed. A drive system for driving an AC electric machine provides a primary current excitation to drive the AC electric machine, the primary current excitation comprising a current vector having a magnitude and angle. The drive system injects a carrier signal to the AC electric machine that is superimposed onto the current vector, with the carrier signal being selected to generate a carrier response signal that has sensitivity to magnetic alignment information of the AC electric machine at its operating point. The drive system measures at least one magnetic alignment signature of the AC electric machine from the generated carrier response signal and controls an orientation of the current vector using the measured at least one magnetic alignment signature, so as to achieve a desired magnetic operation of the AC electric machine.