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:
Sep. 27, 2011
Filed:
May. 27, 2008
Applicant:
Takeshi Omaru, Chiyoda-ku, JP;
Inventor:
Takeshi Omaru, Chiyoda-ku, JP;
Assignee:
Mitsubishi Electric Corporation, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
H02H 3/08 (2006.01);
U.S. Cl.
CPC ...
Abstract
A failure detection device detects the voltage across the main electrodes of an IGBT via a diode. The failure detection device determines occurrence of short-circuit failure in the IGBT when the anode voltage of the diode is lower than a first predetermined reference voltage. Determination can be made, excluding the case of a proper operation corresponding to a flywheel diode in an ON state, preferably together with the condition that the anode voltage of the diode is higher than a second predetermined reference voltage.