Patents by Inventor Van A. Niemela

Van A. Niemela has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9276402
    Abstract: An example system may comprise at least one solar panel including a plurality of photovoltaic cells, wherein the photovoltaic cells are grouped into at least a first group of cells and a second group of cells. The first and second groups of cells may be coupled in series to a DC bus to deliver DC voltage and power to the DC bus. The system may further include first power conversion circuitry configured to generate power from the first group of cells and second power conversion circuitry configured to generate power from the second group of cells, and inverter circuitry coupled to the DC bus and configured to generate AC power from the DC bus. The first power conversion circuitry may be configured to automatically adjust at least one of an output voltage or power delivered to the DC bus based on an operating point of the second power conversion circuitry.
    Type: Grant
    Filed: November 7, 2012
    Date of Patent: March 1, 2016
    Assignee: Fairchild Semiconductor Corporation
    Inventor: Van Niemela
  • Patent number: 6069799
    Abstract: A power converter having an input and output and a method of operating the power converter. In one embodiment, the power converter includes a power transformer having primary and secondary windings and a power switch coupled to the input and configured to impress an input voltage across the primary winding. The power converter further includes a hybridge synchronous rectifier coupled to the secondary winding and including first and second synchronous rectifier switches. The power converter still further includes a separate drive winding wound on the power transformer and coupled between the first and second synchronous rectifier switches. The separate drive winding is configured to alternately energize the first and second synchronous rectifier switches.
    Type: Grant
    Filed: May 4, 1998
    Date of Patent: May 30, 2000
    Assignee: Lucent Technologies Inc.
    Inventors: Wayne C. Bowman, Van A. Niemela, Allen F. Rozman
  • Patent number: 5742491
    Abstract: A drive circuit for a converter and a method of driving a converter. The converter includes an inverter and a synchronous rectifier. The drive circuit includes: (1) a modulation circuit for generating a drive waveform for controlling the inverter and the synchronous rectifier employing a negative feedback loop, (2) a modification circuit, coupled to the modulation circuit, for sensing an operating condition of the converter and shifting a portion of the drive waveform as a function of the operating condition, the modification circuit thereby creating a variable drive waveform from the drive waveform without employing negative feedback and (3) a transmission circuit, coupled to the modification circuit, for applying the variable drive waveform to the converter, thereby allowing a variable nonconcurrent change in state of the inverter and the synchronous rectifier according to the function of the operating condition.
    Type: Grant
    Filed: August 9, 1995
    Date of Patent: April 21, 1998
    Assignee: Lucent Technologies Inc.
    Inventors: Wayne C. Bowman, Van A. Niemela
  • Patent number: 5590032
    Abstract: A power converter with a self synchronized synchronous rectifier includes one or two drive windings to provide positive drive to the control electrodes of the controlled switches (FETs) of a self synchronized synchronous rectifier. The polarities of these windings are selected so that the switched devices are driven appropriately to rectify the periodic signal output of the secondary winding of the power transformer of the converter. In some arrangements one or two drive windings are included as extra windings in the power transformer and connected to provide the proper polarity drive signals. The turn ratios of the drive windings to the other windings are selected to provide the proper gate drive signal levels. In an alternative arrangement a separate drive transformer may be provided to supply the gate drive signals.
    Type: Grant
    Filed: May 25, 1995
    Date of Patent: December 31, 1996
    Assignee: Lucent Technologies Inc.
    Inventors: Wayne C. Bowman, Van A. Niemela
  • Patent number: RE37221
    Abstract: A drive circuit for a converter and a method of driving a converter. The converter includes an inverter and a synchronous rectifier. The drive circuit includes: (1) a modulation circuit for generating a drive waveform for controlling the inverter and the synchronous rectifier employing a negative feedback loop, (2) a modification circuit, coupled to the modulation circuit, for sensing an operating condition of the converter and shifting a portion of the drive waveform as a function of the operating condition, the modification circuit thereby creating a variable drive waveform from the drive waveform without employing negative feedback and (3) a transmission circuit, coupled to the modification circuit, for applying the variable drive waveform to the converter, thereby allowing a variable nonconcurrent change in state of the inverter and the synchronous rectifier according to the function of the operating condition.
    Type: Grant
    Filed: April 20, 2000
    Date of Patent: June 12, 2001
    Assignee: Lucent Technologies Inc.
    Inventors: Wayne C. Bowman, Van A. Niemela
  • Patent number: RE37510
    Abstract: A power converter with a self synchronized synchronous rectifier includes one or two drive windings to provide positive drive to the control electrodes of the controlled switches (FETs) of a self synchronized synchronous rectifier. The polarities of these windings am selected so that the switched devices are driven appropriately to rectify the periodic signal output of the secondary winding of the power transformer of the converter. In some arrangements one or two drive windings are included as extra windings in the power transformer and connected to provide the proper polarity drive signals. The turn ratios of the drive windings to the other windings are selected to provide the proper gate drive signal levels. In an alternative arrangement a separate drive transformer may be provided to supply the gate drive signals.
    Type: Grant
    Filed: December 17, 1998
    Date of Patent: January 15, 2002
    Assignee: Lucent Technologies Inc.
    Inventors: Wayne C. Bowman, Van A. Niemela