Patents by Inventor Ludwig Abraham

Ludwig Abraham 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).

  • Control method for a three-phase self-excited inverter
    Patent number: 4228491
    Abstract: A control method for a three-phase self-excited inverter which is fed from a dc voltage source and in which the fundamental oscillation of the output voltage is adjustable in frequency and amplitude, in particular by the subharmonic method, and wherein the pulsing or timing is always done in only one of three phases (R, S or T) such that 60.degree.-wide pulse regions are arranged symmetric to the maximum and minimum of the fundamental voltage oscillation of each phase (R, S or T) and overlap each fundamental voltage oscillation.
    Type: Grant
    Filed: October 26, 1978
    Date of Patent: October 14, 1980
    Assignee: Brown, Boveri & Cie Aktiengesellschaft
    Inventors: Ludwig Abraham, Armando Moschetti