Patents Assigned to Direct Grid Technologies, LLC
  • Patent number: 8422249
    Abstract: A microinverter is disclosed for use in a solar power installation. The microinverter incorporates a voltage-to-current control loop that initially converts output current produced by a photovoltaic panel into a pulse width modulated output synchronized and phase-locked to the utility grid voltage. The duty cycle of that modulated output is specified by output power internally requested from the microinverter. This modulated output is converted into a full-wave rectified unipolar waveform that is converted, through a Commutator, into a bipolar AC output that is also phase-locked and synchronized to the grid voltage. The commutator uses an H-bridge composed of four FETs, with each of two diagonally-oriented pairs of these FETs being advantageously switched on substantially at zero-crossing points in the grid voltage.
    Type: Grant
    Filed: August 25, 2011
    Date of Patent: April 16, 2013
    Assignee: Direct Grid Technologies, LLC
    Inventors: Frank G. Cooper, Eric J. Hoffman, Richard MacArthur
  • Publication number: 20130051092
    Abstract: A microinverter is disclosed for use in a solar power installation. The microinverter incorporates a voltage-to-current control loop that initially converts output current produced by a photovoltaic panel into a pulse width modulated output synchronized and phase-locked to the utility grid voltage. The duty cycle of that modulated output is specified by output power internally requested from the microinverter. This modulated output is converted into a full-wave rectified unipolar waveform that is converted, through a Commutator, into a bipolar AC output that is also phase-locked and synchronized to the grid voltage. The commutator uses an H-bridge composed of four FETs, with each of two diagonally-oriented pairs of these FETs being advantageously switched on substantially at zero-crossing points in the grid voltage.
    Type: Application
    Filed: August 25, 2011
    Publication date: February 28, 2013
    Applicant: Direct Grid Technologies LLC
    Inventors: Frank G. Cooper, Eric J. Hoffman, Richard MacArthur
  • Patent number: 8358506
    Abstract: A mechanical arrangement for use in implementing a galvanically-isolated, low-profile micro-inverter primarily, though not exclusively, intended for use with solar panels. The micro-inverter contains a circuitry assembly having a planar transformer formed of two abutting E-shaped core halves, and a chopper device assembly with all chopper devices mounted to a common thermally-conductive plate. To provide passive cooling, heat conduction paths are established, via separate compressive thermally-conductive pads, from a top surface of a top core half of the transformer and from a bottom surface of the conductive plate to large-area portions of opposing internal surfaces of top and base portions, respectively, of an enclosure.
    Type: Grant
    Filed: August 27, 2010
    Date of Patent: January 22, 2013
    Assignee: Direct Grid Technologies, LLC
    Inventors: Frank G. Cooper, Eric J. Hoffman
  • Publication number: 20120050999
    Abstract: A mechanical arrangement for use in implementing a galvanically-isolated, low-profile micro-inverter primarily, though not exclusively, intended for use with solar panels. The micro-inverter contains a circuitry assembly having a planar transformer formed of two abutting E-shaped core halves, and a chopper device assembly with all chopper devices mounted to a common thermally-conductive plate. To provide passive cooling, heat conduction paths are established, via separate compressive thermally-conductive pads, from a top surface of a top core half of the transformer and from a bottom surface of the conductive plate to large-area portions of opposing internal surfaces of top and base portions, respectively, of an enclosure.
    Type: Application
    Filed: August 27, 2010
    Publication date: March 1, 2012
    Applicant: Direct Grid Technologies LLC
    Inventors: Frank G. Cooper, Eric J. Hoffman