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:
Jun. 07, 2011
Filed:
Aug. 18, 2004
Masataka Sasaki, Hitachi, JP;
Hideki Miyazaki, Hitachi, JP;
Katsumi Ishikawa, Hitachinaka, JP;
Keiji Maekawa, Hitachinaka, JP;
Masataka Sasaki, Hitachi, JP;
Hideki Miyazaki, Hitachi, JP;
Katsumi Ishikawa, Hitachinaka, JP;
Keiji Maekawa, Hitachinaka, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An inverter system having a semiconductor device, and a railway vehicle using this inverter, provide a more accurate determination of whether an abnormal heat generation from the inverter is associated with an error of the inverter system or is due to other causes, by use of a plurality of temperature detecting elements at a plurality of sites associated with the semiconductor device. An error detection section applies inputs from the temperature detecting elements, captures a trend of the differential value based on the plurality of temperature inputs using period sampling wherein an error associated with the semiconductor device, and not from some other condition such as outside environment temperature, is determined based on differences from, or a change in, the initial trend.