Patents Represented by Attorney Ole K. Nilssen
  • Patent number: 5459375
    Abstract: In a power-line-operated current-fed parallel-tuned electronic ballast, power-factor-correction and line current harmonics-reduction are attained by placing a high-frequency inductor as well as a high-frequency voltage source in series with the unfiltered DC output of a bridge rectifier connected with the power line voltage. The unfiltered DC output is then supplied to a filter capacitor through a phase-controlled field-effect transistor, thereby to provide a DC voltage of controllably constant magnitude to the ballast's inverter while at the same time drawing power from the power line with a power factor well over 90% and with a total harmonics content well under 20%.
    Type: Grant
    Filed: October 20, 1994
    Date of Patent: October 17, 1995
    Inventor: Ole K. Nilssen