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:
Jan. 12, 2016
Filed:
May. 15, 2012
Yoichi Enomoto, Shiga, JP;
Hiroshi Takao, Osaka, JP;
Yoshihiko Maeda, Hyogo, JP;
Hoshihito Okada, Osaka, JP;
Yoichi Enomoto, Shiga, JP;
Hiroshi Takao, Osaka, JP;
Yoshihiko Maeda, Hyogo, JP;
Hoshihito Okada, Osaka, JP;
Abstract
A motor drive circuit comprises: a DC power supply; power supply lines; an inverter which has upper arm switch elements and lower arm switch elements; and a detection unit for detecting, based on a power state on the previous stage side of the inverter, the insulation resistances of the motor drive circuit and the motor. The detection unit performs a first detection operation for detecting the insulation resistances by using the output of the DC power supply while the upper arm switch elements and the lower arm switch elements are all turned off and a second detection operation for detecting the insulation resistances by using the output of the DC power supply while the elements of one of the upper arm switch elements and the lower arm switch elements are all turned off and at least one of the elements of the other one is turned on.