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:
Mar. 18, 1986
Filed:
Oct. 20, 1982
Alberto Abbondanti, Penn Hills, PA (US);
Westinghouse Electric Corp., Pittsburgh, PA (US);
Abstract
A microprocessor-based solid state AC-DC converter system makes use of the microprocessor facility to implement sequential thyristor firing at selected delay angles. A first timer at the AC line fundamental frequency supplies to the microprocessor a numerical master ramp count, from which individual ramp counts are calculated which relate to the individual thyristors to be fired in sequence. From such an individual ramp count by comparison with a delay angle reference count the microprocessor calculates the number of units of time needed until zero count on the individual ramp. A second timer is preset at an initial count value equal to such calculated number of units of time and the second timer is run to count-down. The thyristor next to be fired is triggered when zero count occurs.