Patents by Inventor Jan T. Holmgren

Jan T. Holmgren 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).

  • Filter equipment for power lines
    Patent number: 4939486
    Abstract: Filter equipment for power lines has a double-tuned shunt filter (F1) which has a series resonance circuit (C1, L1) connected in series with a parallel resonance circuit (C2, L2). The capacitor banks of the two resonance circuits are formed so as to have opposite signs on the temperature coefficent of the capacitor capacitance.
    Type: Grant
    Filed: January 4, 1989
    Date of Patent: July 3, 1990
    Assignee: Asea Brown Boveri AB
    Inventors: Bernt Bergdahl, Jan T. Holmgren