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:
Apr. 12, 2005
Filed:
Mar. 28, 2002
Toru Tazawa, Ibaraki, JP;
Kazushige Narazaki, Katano, JP;
Tomokuni Iijima, Osaka, JP;
Hideo Matsushiro, Kusatsu, JP;
Subrata Saha, Moriguchi, JP;
Toru Tazawa, Ibaraki, JP;
Kazushige Narazaki, Katano, JP;
Tomokuni Iijima, Osaka, JP;
Hideo Matsushiro, Kusatsu, JP;
Subrata Saha, Moriguchi, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
In a brushless motor control method and a brushless motor controller in accordance with the present invention, a rotor rotation position detection means detects the time of the intersection of a detected induced voltage and an induced voltage reference value. In addition, a motor speed calculation means calculates the rotation speed of a brushless motor on the basis of the interval of the intersection times detected by the rotor rotation position detection means. Furthermore, a speed control means outputs a duty factor index on the basis of the deviation between the command speed and the rotation speed of the brushless motor. Still further, a switching signal generation means outputs switching signals to groups of switching devices on the basis of the rotation speed and the duty factor index at the time of the intersection.