Abstract: A method and apparatus for converting power comprising an input bridge having an input adapted for coupling to a DC source, a piezoelectric transformer having an input coupled to an output of the input bridge, and an output bridge having an input coupled to an output of the piezoelectric transformer and an output adapted to couple to a load. A trajectory controller, coupled to the input bridge and output bridge, (1) measures current and voltage in the input bridge, the output bridge or both, (2) measures a current into or out of the piezoelectric transformer, (3) determines switch timing for control signals for the input bridge and output bridge based upon the measured current and/or voltage, and (4) applies the control signals to the input bridge and output bridge.

Abstract: A microinverter is provided herein and comprises DC side MOSFETs connected to an input side of the microinverter, AC side MOSFETs connected to an output of the microinverter, and a plurality of gate drivers connected to the AC side MOSFETs and configured to automatically drive the microinverter without a DC voltage being applied to the input side of the microinverter.

Abstract: Methods and apparatus which use a microinverter comprising integrated neutral forming function for off-grid facilities are provided herein. For example, a microinverter configured for use with an AC storage system comprises switching circuitry connected at an AC output of the microinverter, a three-line connector connected at the AC output and comprising a neutral line connected between two lines configured to connect to at least one of a single phase grid system or a split phase grid system, wherein the neutral line is connected to the microinverter at a point that maintains a mid-way voltage between the two lines voltage.

Abstract: The present disclosure provides a transformer configured for use with a power converter of an energy management system. For example, the transformer comprises an adjustable flux-shunt configured to be positioned onto an inner round limb of a core half and rotated around the inner round limb to obtain an adequate leakage inductance corresponding to a set position of the adjustable flux-shunt.

Abstract: A bridge configured for use with a power converter is provided herein and comprises a switch comprising a Gallium-Nitride (GaN) High Electron Mobility Transistor and a Gate driver coupled to the Gallium-Nitride (GaN) High Electron Mobility Transistor and configured to provide a turn on signal to the Gallium-Nitride (GaN) High Electron Mobility Transistor at a first time so that the Gallium-Nitride (GaN) High Electron Mobility Transistor turns on at a second time that is different from the first time.

Abstract: A cycloconverter configured for use with a power converter is provided herein and comprises a bidirectional switch comprising a pair of Gallium-Nitride (GaN) High Electron Mobility Transistors and a Gate driver coupled to a gate of each of the pair of Gallium-Nitride (GaN) High Electron Mobility Transistors and configured to provide at least one of independent turn-on and turn-off outputs for implementing asymmetrical Gate drive characteristics, a voltage regulated supply to determine a gate turn-on voltage, and a gate turn-off voltage supply that can sink and source current.

Abstract: Methods and apparatus for active EMI cancellation in a switch mode power supply are provided herein. For example, an apparatus comprises an active EMI cancellation circuit coupled to a switch mode power supply circuit comprising an isolation transformer, wherein the active EMI cancellation circuit is positioned such that current flow through an EMI coupling capacitor substantially matches displacement current flow through a primary-to-secondary interwinding capacitance of the isolation transformer.

Abstract: A switched mode power converter is provided herein and comprises a cycloconverter comprising a plurality of switches, wherein each switch of the plurality of switches is a native four quadrant bi-directional switch with a common drift region configured to allow current flow in a first direction from a first source terminal to second source terminal and in a second direction from the second source terminal to the first direction.

Abstract: An apparatus configured for use with a microinverter of an energy management system is provided. For example, apparatus can comprise a cascaded current transformer configuration comprising a first current transformer having a first primary winding configured to couple to a secondary winding of a power transformer of the microinverter and having a first secondary winding coupled to a second primary winding of a second current transformer having a second secondary winding coupled to a measurement device configured to measure a current of the microinverter.

Abstract: A cycloconverter configured for use with a power converter is provided herein and comprises a bidirectional switch operable in a first mode of operation when an AC mains voltage is equal to or greater than a predetermined voltage and a second mode of operation when the AC mains voltage is less than the predetermined voltage, such that during zero voltage switching (ZVS) commutations a first Gate of a first pair of Gallium-Nitride (GaN) High Electron Mobility Transistors is on, a second Gate of the first pair of Gallium-Nitride (GaN) High Electron Mobility Transistors is off, and the first Gate and the second Gate of a second pair of Gallium-Nitride (GaN) High Electron Mobility Transistors are off.

Abstract: A resonant parallel triple active bridge converter comprising a DC port configured to receive DC energy, an AC port configured to produce AC energy, and an AC line cycle energy storage port, coupled to both the DC port and the AC port, where the AC line cycle energy storage port comprises an energy storage device for storing energy during an energy conversion process.

Abstract: A microinverter inverter is provided and comprises an output comprising a four-way connector comprising three power input/output connecters and a voltage monitoring and power line communications connector. The output is configured to connect to an AC cable comprising a rotatable four-way connector comprising three phase wires and a neutral wire which allows the microinverter to operate in at least one of a three-phase grid-tied mode of operation, a three-phase off-grid neutral-forming mode of operation, a two-phase grid-tied mode of operation, a two-phase off-grid neutral-forming mode of operation, or a split-phase and single-phase grid tied and off-grid neutral-forming mode of operation when the microinverter is connected to the AC cable.

Abstract: Methods and apparatus for producing helix windings used for a transformer are provided. For example, apparatus comprise an electrically conductive mandrel comprising an elongated body, a head comprising an eyelet detail, and a winding structure disposed along the elongated body.

Abstract: An apparatus for measuring current in a power converter is provided. The apparatus comprises a state space observer configured to provide a statistically most probable state of the power converter and an analog digital converter comprising a comparator configured to compare a first state space observer current approximation to a real time current input signal to determine if the first state space observer current approximation is too high or too low and a counter configured to be incremented or decremented based on a result of a comparison at the comparator, wherein an output of the counter is input to the state space observer and added to the first state space observer current approximation to calculate a second state space observer current approximation that will be one count closer to a final correct value.

Abstract: Apparatus for performing substrate voltage management is provided herein and comprises an active substrate voltage management circuit configured to be coupled to a substrate of a bidirectional gallium nitride high electron mobility transistor comprising a first source and a second source. The active substrate voltage management circuit comprises a first circuit that is connected to the first source and a second circuit that is connected to a second source such that when the bidirectional gallium nitride high electron mobility transistor is operational one of the first circuit or the second circuit connects one of the first source to the substrate or the second source to the substrate, respectively, to control a bias voltage applied to the substrate.

Abstract: Apparatus and method for controlling reactive power. In one embodiment, the apparatus comprises a bidirectional power converter comprising a switched mode cycloconverter for generating AC power having a desired amount of a reactive power component.

Abstract: Methods and apparatus which use a microinverter comprising integrated neutral forming function for off-grid facilities are provided herein. For example, a microinverter configured for use with an AC storage system comprises switching circuitry connected at an AC output of the microinverter, a three-line connector connected at the AC output and comprising a neutral line connected between two lines configured to connect to at least one of a single phase grid system or a split phase grid system, wherein the neutral line is connected to the microinverter at a point that maintains a mid-way voltage between the two lines voltage.

Abstract: A method and apparatus for converting power comprising an input bridge having an input adapted for coupling to a DC source, a piezoelectric transformer having an input coupled to an output of the input bridge, and an output bridge having an input coupled to an output of the piezoelectric transformer and an output adapted to couple to a load. A trajectory controller, coupled to the input bridge and output bridge, (1) measures current and voltage in the input bridge, the output bridge or both, (2) measures a current into or out of the piezoelectric transformer, (3) determines switch timing for control signals for the input bridge and output bridge based upon the measured current and/or voltage, and (4) applies the control signals to the input bridge and output bridge.

Abstract: Methods and apparatus for producing helix windings used for a transformer are provided. For example, apparatus comprise an electrically conductive mandrel comprising an elongated body, a head comprising an eyelet detail, and a winding structure disposed along the elongated body.

Abstract: A microinverter inverter is provided and comprises an output comprising a four-way connector comprising three power input/output connecters and a voltage monitoring and power line communications connector. The output is configured to connect to an AC cable comprising a rotatable four-way connector comprising three phase wires and a neutral wire which allows the microinverter to operate in at least one of a three-phase grid-tied mode of operation, a three-phase off-grid neutral-forming mode of operation, a two-phase grid-tied mode of operation, a two-phase off-grid neutral-forming mode of operation, or a split-phase and single-phase grid tied and off-grid neutral-forming mode of operation when the microinverter is connected to the AC cable.