Patents by Inventor Alistair Allan Macfarlane

Alistair Allan Macfarlane 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).

  • Semi resonant switching regulator, power factor control and LED lighting
    Patent number: 8830702
    Abstract: Described are improvements in power factor control and systems embodying said improved power factor control. Improvements lie in a method of zero voltage switching in which a capacitor is placed in parallel with a switching device, and the switching device is operated responsive to a change in the polarity of the current through the capacitor. Switching therefore occurs at zero or close to zero voltage across the switching device in both on and off modes resulting in very low switching losses and electromagnetic interference. Systems employing the method include a power factor controller, LED light source, boost converter and a power source comprising one or more photovoltaic cells.
    Type: Grant
    Filed: July 1, 2011
    Date of Patent: September 9, 2014
    Inventor: Alistair Allan Macfarlane
  • SEMI RESONANT SWITCHING REGULATOR, POWER FACTOR CONTROL AND LED LIGHTING
    Publication number: 20120169240
    Abstract: Described are improvements in power factor control and systems embodying said improved power factor control. Improvements lie in a method of zero voltage switching in which a capacitor is placed in parallel with a switching device, and the switching device is operated responsive to a change in the polarity of the current through the capacitor. Switching therefore occurs at zero or close to zero voltage across the switching device in both on and off modes resulting in very low switching losses and electromagnetic interference. Systems employing the method include a power factor controller, LED light source, boost converter and a power source comprising one or more photovoltaic cells.
    Type: Application
    Filed: July 1, 2011
    Publication date: July 5, 2012
    Inventor: Alistair Allan Macfarlane