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:
Apr. 01, 1997
Filed:
Jan. 26, 1996
Shotaro Murakami, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A power converter protecting apparatus include series transformers connected in series to phase power lines, respectively, of an electric power system, power converters connected to secondary windings of the transformers, respectively, a current detector for detecting system currents flowing through the phase power lines, a current detector for detecting converter currents flowing to the power converters from the secondary windings, respectively, a high-speed decision circuit for outputting a decision signal upon determination of occurrence of a system fault on the basis of the system current, a switch for issuing an output voltage zero command upon reception of the fault decision signal, and a pulse generating circuit for controlling a gate pulse signal supplied to the power converters for setting to zero the outputs of the power converters in response to the output voltage zero command at a time point when the converter current decreases below an allowable breaking current thereof.