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, 2013
Filed:
Feb. 25, 2011
Ikuya Sato, Sagamihara, JP;
Ikuya Sato, Sagamihara, JP;
Fuji Electric Co., Ltd., Kawasaki-Shi, JP;
Abstract
An electric power converter includes a control unit outputting a PWM signal, a bridge circuit producing AC electric power supplied to a motor by turning semiconductor switching devices in the bridge on and off in response to PWM signals, a cut off unit cutting the PWM signals off from the bridge circuit in response to a gate signal, and a monitoring unit generating a test signal for checking the cut off unit. The cut off unit includes a switching circuit switching between the test signal and an external cut off signal, and a delay circuit that delays the output of the switching circuit. The arrangement enables the electric power converter to monitor as to whether the cut off unit is abnormal without stopping the operation of the electric power converter.