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:
Oct. 05, 2010
Filed:
Sep. 06, 2007
Raymond Y. Liu, Monterey Park, CA (US);
Estella C. Chung, West Hills, CA (US);
William K. Morita, Jr., West Hills, CA (US);
Raymond Y. Liu, Monterey Park, CA (US);
Estella C. Chung, West Hills, CA (US);
William K. Morita, Jr., West Hills, CA (US);
Woodward HRT, Inc., Santa Clara, CA (US);
Abstract
A technique can recover from motor stalls caused by misalignment of motor position sensors such as Hall-effect sensors. In a normal operating mode, a motor controller provides motor drive current to the motor windings based on the sensor signals according to a normal commutation sequence, and monitors for occurrence of a motor stall condition. Upon detecting the motor stall condition, the motor controller first momentarily drives the windings according to one of an advanced commutation state and a delayed commutation state each adjacent to the given commutation state in the normal commutation sequence, and determines whether the motor stall condition persists. If the stall condition persists, then the motor controller next momentarily drives the windings according to the other of the advanced commutation state and the delayed commutation state. By this action, the controller attempts operation at both preceding and succeeding portions of the torque characteristic, such that operation with increased torque is ensured even though the direction of the sensor misalignment is unknown.