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:
May. 11, 1999
Filed:
May. 15, 1997
Tomoya Okuno, Okazaki, JP;
Hiroyuki Sakakibara, Hekinan, JP;
Hiroya Tsuji, Kariya, JP;
Kazuyoshi Obayashi, Kariya, JP;
Denso Corporation, Kariya, JP;
Nippon Soken, Inc., Nishio, JP;
Abstract
A permanent magnet synchronous motor having multiple-phase armature windings and a rotor is subjected to sensor-less control. Phase voltages are generated in response to voltage command values. The generated phase voltages are applied to the armature windings. Phase currents through the armature windings are detected. The detected phase currents depend on the voltage command values. An angular position and an angular velocity of the rotor are calculated from the detected phase currents. The voltage command values are adjusted in response to the calculated angular position and the calculated angular velocity of the rotor to implement feedback control of the motor. An angular velocity of the rotor is estimated from a time-domain variation in the calculated angular position of the rotor. A determination is made as to whether or not the calculated angular velocity of the rotor and the estimated angular velocity of the rotor are substantially equal to each other. The calculated angular position of the rotor is changed by a predetermined phase value and is thereby corrected when it is determined that the calculated angular velocity of the rotor and the estimated angular velocity of the rotor are not substantially equal to each other.