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:
Jul. 10, 1990
Filed:
Jan. 24, 1989
David A Fox, Shawnee Township, OH (US);
Ralph D Jessee, Shawnee Township, OH (US);
Westinghouse Electric Corp., Pittsburgh, PA (US);
Abstract
This invention controls the operation of solid state swithing devices in an output stage of an electronic inverter by using a counter to maintain a fixed delay between transition points in a switching command signal and a modified switch operation signal. The counter begins counting clock pulses following a transition in the switch command signal and produces a transition point in a switch drive signal when it reaches a predetermined count. The solid state switching device changes conduction states in response to the transition points in the switch drive signal. This produces a transition point in a switch operation signal. Those transition points are time-shifted by an amount corresponding to the level of DC voltage in the inverter output to produce the modified switch operation signal. The counter stops counting in response to one of the transition points in that modified switch operation signal. By starting and stopping the counter in this manner, a fixed delay is maintained between transition points in the command signal and the modified switch operation signal.