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:
May. 29, 1979
Filed:
Apr. 10, 1978
Herbert W Weiss, Salem, VA (US);
General Electric Company, Salem, VA (US);
Abstract
A method of controlling the thyristors of an a.c. to d.c. bridge converter, having neutral connected thyristors, at relatively low power levels by gating each phase leg thyristor conductive for a predetermined minimum period within the electrical separation between adjacent line to neutral phase voltages and immediately gating the respective neutral leg thyristor conductive for the remainder of the period such that there are no intervals in the cycle when both neutral leg thyristors are in conduction. In a three phase bridge converter system, this requires at least 60 electrical degrees minimum conduction for each phase leg thyristor followed by a 60.degree. conduction of the neutral leg thyristors. In any event, the sum of the phase leg conduction and the neutral leg conductions is always equal to 120.degree. in a three phase system. This control method improves the response to a reverse command voltage by assuring that a phase leg thyristor is conductive, thus making a transition from the first to fourth quadrant operation at maximum possible speed.