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:
Mar. 25, 2014
Filed:
May. 16, 2011
John K. Rote, Allen, TX (US);
Seil OH, Plano, TX (US);
Brian L. Schmidt, Sachse, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
To achieve peak acoustic and power performance, the coil or applied current should be in phase or substantially aligned with the back electromotive force (back-EMF) voltage. However, there are generally phase differences between the applied current and back-EMF voltage that are induced by the impedance of the brushless DC motor (which can vary based on conditions, such as temperature and motor speed). Traditionally, compensation for these phase differences was provided manually and on an as-needed basis. Here, however, a system and method are provided that automatically perform a commutation advance by incrementally adjusting a drive signal over successive commutation cycles when the applied current and back-EMF voltage are misaligned.