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. 03, 2010
Filed:
Mar. 08, 2007
Shingo Fukamizu, Osaka, JP;
Yasunori Yamamoto, Osaka, JP;
Hideaki Mori, Osaka, JP;
Shinichi Kuroshima, Osaka, JP;
Shingo Fukamizu, Osaka, JP;
Yasunori Yamamoto, Osaka, JP;
Hideaki Mori, Osaka, JP;
Shinichi Kuroshima, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
Problems with accuracy reading position detection signal peaks and minute phase differences in the detection current make motor drive control easily susceptible to differences in motor characteristics. The rotor position is determined based on whether or not a terminal difference voltage, which is the difference voltage between the motor terminal voltage and the pseudo-neutral-point voltage when the motor phases are selectively energized, exceeds a specific threshold value. The phase energized to start the motor is determined based on this determination and the motor is energized accordingly to start. Instead of switching directly from the search step at the initial rotor position to the back-EMF voltage mode, a search and start mode that creates initial rotor speed sufficient to start the motor is executed before entering the back-EMF voltage mode.