Patents by Inventor Leif-Erik Wraee

Leif-Erik Wraee 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).

  • Wind mill power flow control with dump load and power converter
    Patent number: 8436490
    Abstract: A wind mill apparatus for generating electric power to a grid point of an electric network. The apparatus includes a wind rotor, an electric generator operatively connected to the wind rotor, and an electric multiphase ac link operatively connecting the generator to the grid point. The ac link includes a first current path including a switchgear, a second current path including a dc link including a first converter operatively connected to the generator, a second converter operatively connected to the grid point, and a capacitor operatively connected between the conductors of the dc link. The ac link further includes a connectable multiphase dump load for blocking during a fault condition on the network the reactive power flow in the ac link, yet providing a reduced transfer of active power.
    Type: Grant
    Filed: August 30, 2006
    Date of Patent: May 7, 2013
    Assignee: ABB Research Ltd.
    Inventors: Lars Gertmar, Hans Christian Christensen, Erik Kolby Nielsen, Jouko Niiranen, Stefan Thorburn-Johansson, Leif-Erik Wraee