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:
Nov. 08, 2011
Filed:
May. 20, 2009
Hiroyasu Baba, Nishio, JP;
Yuji Hayashi, Kasugai, JP;
Naoki Yamamoto, Takahama, JP;
Kiyoshi Nagata, Nagoya, JP;
Masaya Ootake, Kariya, JP;
Hiroyasu Baba, Nishio, JP;
Yuji Hayashi, Kasugai, JP;
Naoki Yamamoto, Takahama, JP;
Kiyoshi Nagata, Nagoya, JP;
Masaya Ootake, Kariya, JP;
Denso Corporation, Kariya, JP;
Nippon Soken, Inc., Nishio, JP;
Abstract
An apparatus for estimating rotor position for brushless motors capable of accurately estimating rotor position is provided. The apparatus may be used as a start-up system for brushless motors. The apparatus performs accurate estimation even though power source voltage fluctuates, and is able to provide compact configuration. The apparatus supplies voltage to the coils respectively. In each supplying period, the apparatus counts voltage supply period of time until current value reaches to a current threshold value. Since a coil indicative of rotor stop position is prone to be magnetically saturated. The apparatus estimates the rotor stop position based on the voltage supply periods. Then, the apparatus starts a switching sequence based on the rotor stop position.