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:
Jun. 23, 2009
Filed:
Apr. 17, 2007
Chen-yeh Lee, Taoyuan Shien, TW;
Chen-Yeh Lee, Taoyuan Shien, TW;
Delta Electronics, Inc., Taoyuan Hsien, TW;
Abstract
A method for detecting initial magnetic pole position in permanent-magnet motor first determines a PWM pulse width Dt applied to stator, where the PWM pulse width Dt depends on motor parameters. Six voltage vectors are then successively applied to the stators and the associated current rising time are calculated. The position of rotor is determined based on the shortest current rising time. The voltage vectors are again successively applied to the stators to recalculate the position of rotor. The position of rotor can be precisely determined when the two calculations are consistent. When the two calculations are not consistent, the voltage vectors are again successively applied to the stators to recalculate the position of rotor until the calculations are consistent. The set current level can be larger than the motor rated current, for example, 160% motor rated current, to facilitate the determination of current rising time. The set current level can be 160% drive rated current when the motor rated current is larger than the drive rated current.