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:
Aug. 18, 2015
Filed:
Dec. 23, 2013
Lei BI, Singapore, CN;
Lei Bi, Singapore, CN;
FORTIOR TECHNOLOGY (SHENZHEN) CO., LTD., Shenzhen, CN;
Abstract
A sensorless driving method for a single phase alternating current permanent magnet motor is described. The method comprises a starting drive mode and a stable drive mode. The starting drive mode comprises inputting a first current to drive a rotor to rotate to a stable position, the first current comprising a pulse current flowing in a first direction for a first predetermined starting time interval and a constant current flowing in a second direction contrary to the first direction for a second predetermined time interval, terminating the first current, determining generation of a back electromotive force, detecting a first zero crossing point of the back electromotive force, inputting a second current for a first charge time interval, waiting for a first post-charge time interval, detecting a second zero crossing point to define a previous half period between the first zero crossing point and the second crossing point, inputting the second current for a second charge time interval, waiting for a second post-charge time interval, and detecting speed of the rotor to compare the speed to a predetermined value. The second current flows in a direction in which the back electromotive force is generated.