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. 02, 2004
Filed:
Jul. 11, 2003
Nobuyuki Imai, Wako, JP;
Yutaka Takahashi, Wako, JP;
Honda Giken Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
An angle detector detects a rotor angle &thgr; of a DC brushless motor using a current value Iu_s detected by a U-phase current sensor and a current value Iw_s detected by a W-phase current sensor when high-frequency voltages vu, vv, vw for detecting a rotor angle are applied by a high-frequency adding unit . The high-frequency adding unit determines the high-frequency voltages vu, vv, vw so that the direction of rotation of the motor and the direction of a revolving magnetic field generated by the high-frequency voltages vu, vv, vw will be opposite to each other. A three-phase/dq converter converts the current values Iw_s, Iu_s into a detected d-axis current Id_s and a detected q-axis current Iq_s using the rotor angle &thgr; detected by the angle detector