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. 04, 2014
Filed:
Jul. 26, 2012
Yoshitaka Iwaji, Hitachinaka, JP;
Shigehisa Aoyagi, Hitachinaka, JP;
Kazuaki Tobari, Hitachiota, JP;
Ryoichi Takahata, Hitachi, JP;
Masaki Hano, Isesaki, JP;
Yoshitaka Iwaji, Hitachinaka, JP;
Shigehisa Aoyagi, Hitachinaka, JP;
Kazuaki Tobari, Hitachiota, JP;
Ryoichi Takahata, Hitachi, JP;
Masaki Hano, Isesaki, JP;
Hitachi Automotive Systems, Ltd., Hitachinaka-shi, JP;
Abstract
In sequentially selecting and driving two phases of the three-phase stator windings of a synchronous motor, detect a speed electromotive voltage of a de-energized phase, relate the speed electromotive voltage to rotor position information beforehand, then count rotor position information backward based on the detected the speed electromotive voltage to estimate rotor position; and then detect rotation speed from the change rate of the rotor position information so as to achieve highly accurate position and speed control.