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. 18, 2019
Filed:
Mar. 01, 2018
Fanuc Corporation, Yamanashi, JP;
Shinichi Mizukami, Yamanashi, JP;
FANUC CORPORATION, Yamanashi, JP;
Abstract
A motor drive apparatus includes: a converter which converts AC power to DC power and to output the DC power to a DC link; an inverter including power devices which converts the DC power to AC power for driving a motor; a capacitor provided in the DC link; a shut-off circuit to open and close an electrical path between the AC power source and the converter; a constant current control unit which performs control in such a manner as to allow a constant current supplied by the capacitor to pass through a detection target power device among the power devices in the inverter; and an abnormality detection unit which detects an abnormality in the detection target power device based on changes in voltage between a collector and an emitter of the detection target power device during a period in which the constant current passes through the detection target power device.