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:
Apr. 01, 2003
Filed:
Mar. 21, 2001
Taro Kishibe, Hyogo, JP;
Yasufumi Ikkai, Hyogo, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A motor controller drives a motor based on signals from commutation sensors (CS signals.) This controller includes (a) a pole position detector for detecting a rotor pole position with edges of the CS signals; (b) a speed detector for detecting a motor speed based on a time interval between the edges of the CS signals; (c) a pole phase detector for estimating a position angle of the rotor based on an output from the position detector and an output from the speed detector; and (d) a phase limiter for restraining the estimated position angle from advancing over a given value. When the limiter continues operating for a certain interval, the controller switches the motor from sine wave driving to rectangular wave driving. This structure allows this controller to drive the motor stably when the motor speed is abruptly changed in the sine wave driving or under field weakening control.