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. 29, 2014
Filed:
Aug. 27, 2010
Tsutomu Tanimoto, Kawasaki, JP;
Tomoya Imazu, Yokohama, JP;
Yoshinori Nakano, Yokohama, JP;
Nissan Motor Co., Ltd., Yokohama-shi, JP;
Meidensha Corporation, Tokyo, JP;
Abstract
Under a condition that rotor rotation speeds ωes are equal, winding wire currents Id, Iq are equal, and winding wire inductances Ld, Lq are equal in first and second electric motors (), a magnet temperature anomaly detector () provided in a microcomputer () calculates a change ratio d(|Φml−Φmr|)/dt of a magnetic flux difference between the first and second electric motors () based on the difference Vql*−Vqr* between a q-axis voltage command value Vql* corresponding to the first electric motor () and a q-axis voltage command value Vqr corresponding to the second electric motor (), and then when the change ratio d(|Φml−Φmr|)/dt of the magnetic flux difference is more than a predetermined threshold Sh, it is determined that a permanent magnet of at least any one of the electric motors () has a temperature anomaly.