Patents by Inventor H.ang.kan Kols

H.ang.kan Kols 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).

  • Method for monitoring of tap changers by acoustic analysis
    Patent number: 6157196
    Abstract: A method for monitoring an on-load tap changer wherein the recording of sound and its conversion into a sound signal are initiated at the beginning of a connection operation of the tap changer and the sound signal is rectified, converted into a signal envelope, sampled digitally and continuously evaluated with respect to the condition of the tap changer by comparing the envelope with at least one fixed or one continuously updated reference envelope. The comparison is carried out selectively by calculating a dimensionless comparison figure T.sub.i which is based on a quantity measure and a variation measure.
    Type: Grant
    Filed: November 12, 1998
    Date of Patent: December 5, 2000
    Assignee: ABB Research Ltd.
    Inventors: Tord Bengtsson, H.ang.kan Kols, Lars Martinsson