Patents by Inventor Freddy de Beer

Freddy de Beer 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).

  • Three-phase AC-to-AC series resonant power converter with reduced number of switches
    Patent number: 5010471
    Abstract: An apparatus and method is disclosed for an improved AC--AC series-resonant converters incorporating power pulse modulation with internal frequencies of tens of kHz is applied to a series-resonant converter system for generating synthesized multiphase bipolar waveforms with reversible power flow and low distortion. The high pulse frequency allows the application of the principle of modulation and demodulation for fast system response. Switches are required which have bidirectional current conduction and voltage blocking ability. The conventional series-resonant AC--AC converter applies a total of 24 anti-parallel thyristors. The circuit configuration of the present invention is a series-resonant AC--AC converter with only 12 thyristors. Use of the converter results in a higher efficiency and lower costs.
    Type: Grant
    Filed: June 26, 1989
    Date of Patent: April 23, 1991
    Assignee: Robert F. Frijouf
    Inventors: J. Ben Klaassens, Hian K. Lauw, Freddy de Beer