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:
Jul. 02, 2002
Filed:
Sep. 07, 2001
Kazuyuki Itoh, Tokyo, JP;
Yoshihisa Okita, Tokyo, JP;
Katsuaki Tanaka, Tokyo, JP;
Yoshinobu Takayanagi, Tokyo, JP;
TDK Corporation, Tokyo, JP;
Abstract
In a power conversion apparatus using a semiconductor switching element, a collector-emitter voltage detecting device is provided to detect the collector-emitter voltage in the semiconductor switching element in the power conversion apparatus in order to comprehensively reduce switching loss and conduction loss arising in a switching element. A base current supplied to the switching element is controlled based on the detected collector-emitter voltage so as to control the collector-emitter voltage or control a regenerative power to be transmitted from a switching element driving power supply to an external auxiliary power supply or the like. This provides an optimum driving in consideration of factors including dispersion in a specific current amplification factor (hfe) of the switching element, variance in the hfe caused by temperature, and variance in the hfe to a current flowing through the switching element, for reducing a sum of conduction loss and driving power of the switching element.