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. 26, 2012
Filed:
Aug. 19, 2009
Applicants:
Shiho Izumi, Hitachinaka, JP;
Satoru Kaneko, Naka, JP;
Hideki Nihei, Hitachiota, JP;
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H02P 6/16 (2006.01);
U.S. Cl.
CPC ...
Abstract
When the torque command value is zero, a set point of DC current for an inverter is calculated to obtain a difference between the set point and a detected DC current so that an error in magnetic pole position may be estimated and corrected. By correcting the magnetic pole position, unwanted power running and regenerative torque of the motor can be avoided and unnecessary charge or discharge to or from a battery can be prevented.