Patents Assigned to Philips Electronics North America Inc.
  • Ballast filtering scheme for reduced harmonic distortion
    Patent number: 5559396
    Abstract: A ballast filter in which the ballast can operate at a total harmonic distortion of power line current of less than 10%. Power dissipated by the filter when at a THD of less than 10% is relatively low. The input impedance of the ballast is chosen to be no greater than twice the equivalent filter impedance of a front end filter and no less than the equivalent filter impedance/1.5. The filter includes a transformer having a core which at times operates within the non-linear region of its B-H curve under nominally rated ballast load conditions.
    Type: Grant
    Filed: October 14, 1994
    Date of Patent: September 24, 1996
    Assignee: Philips Electronics North America Inc.
    Inventors: Gert W. Bruning, Pawel M. Gradzki