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:
Nov. 26, 2013
Filed:
Nov. 14, 2008
Kei Terada, Chiyoda-ku, JP;
Satoshi Aoki, Chiyoda-ku, JP;
Kei Terada, Chiyoda-ku, JP;
Satoshi Aoki, Chiyoda-ku, JP;
Mitsubishi Electric Corporation, Tokyo, JP;
Abstract
If there is static friction, the magnetic pole position estimation is completed at the time when error torque used for magnetic pole position estimation becomes less than the friction, so that there remains magnetic pole error. A problem has been that when the error torque becomes less than a forward static friction, there remains a positive magnetic pole deviation and when the error torque becomes less than a backward static friction, there remains a negative magnetic pole deviation. By shifting in the negative direction and the positive direction initial values for estimating a magnetic pole error in operation sets, a true pole-error estimation value is estimated in the use of a pole-error estimation value having a positive magnetic pole error obtained by the positive shift operation and a negative one obtained by the negative shift operation, which can reduce estimation error due to the static friction.