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:
Dec. 03, 2002
Filed:
Oct. 10, 2001
Shuji Katoh, Hitachiota, JP;
Hiromitsu Sakai, Tokai-mura, JP;
Shigeta Ueda, Hitachi, JP;
Tomomichi Ito, Hitachi, JP;
Hidetoshi Aizawa, Tokai-mura, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A semiconductor electric power converter in accordance with the present invention comprises an arm consisting of an IGBT, a capacitor connected between a collector and a gate of said IGBT, and a gate circuit connected to the gate of said IGBT for controlling the switching operation of said IGBT, wherein a plurality of said arms connected in series are connected in parallel and each midpoint of said arms connected in of series is connected to a load. Thereby the impedance between the gate terminal of the IGBT and the gate circuit is decreased when the gate voltage is higher than the gate voltage command value or the impedance between the gate and the emitter of the IGBT is decreased when the collector voltage is high so that an electric charge stored in the gate is rapidly discharged.