The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 24, 1991
Filed:
Aug. 14, 1990
Loren H Walker, Salem, VA (US);
General Electric Company, Salem, VA (US);
Abstract
A power switching system for controlling the conductivity of a plurality of thyristors of the gate turn-off type (GTOs) which are connected in parallel between two power sources by gradually introducing a time compensation to force the times of turn-off of each of the thyristors toward matched values by determining the turn-off time during each conduction cycle and thereafter advancing or retarding the turn-off signal for the following conduction cycle to correct for the difference in turn-off times. A difference signal is generated between time of turn-off of an average current of the thyristors and the time of turn-off of an individual current in one of the thyristors from which a time advance or delay signal is added to the thyristor turn-off signal in response to the current flowing in a capacitor type integrator. This allows the turn-off times to reach a perfect match during periods in which the current is the same for several cycles.