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. 20, 2004
Filed:
Aug. 09, 2002
Applicant:
Inventors:
Yutaka Sato, Hitachi, JP;
Masahiro Nagasu, Hitachinaka, JP;
Katsumi Ishikawa, Hitachinaka, JP;
Ryuichi Saito, Hitachi, JP;
Satoru Inarida, Hitachinaka, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G08B 1/702 ; H02H 5/04 ; H02H 7/08 ; H02H 7/10 ; H02H 7/122 ;
U.S. Cl.
CPC ...
G08B 1/702 ; H02H 5/04 ; H02H 7/08 ; H02H 7/10 ; H02H 7/122 ;
Abstract
A fault detection system detecting malfunctions or deteriorations, which may result in an inverter fault, is provided. The system has a temperature sensor installed on a semiconductor module to monitor a temperature rise rate. It is judged that an abnormal condition has occurred if the thermal resistance is increased by the deterioration of a soldering layer of the semiconductor module or by drive circuit malfunctions and, as a result, the relation between an operation mode and the temperature rise rate falls outside a predetermined range.