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:
Feb. 25, 2003
Filed:
Feb. 27, 2001
Haruo Koharagi, Taga-gun, JP;
Masaharu Senoh, Narashino, JP;
Keiji Noma, Inba-gun, JP;
Kohei Ishii, Tokyo, JP;
Kazuo Sato, Sakura, JP;
Satoshi Kikuchi, Hitachi, JP;
Miyoshi Takahashi, Hitachi, JP;
Kouki Yamamoto, Hitachinaka, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A permanent magnet rotating electric machine that comprises a stator, into which concentratively wound armature windings are inserted in such a way as to surround a plurality of teeth formed in a stator core, and a rotor having permanent magnets accommodated into a plurality of permanent magnet inserting holes formed in a rotor core. In this rotating electric machine, the permanent magnets are convex V-shaped or U-shaped with respect to a rotor axis. Moreover, nearly V-shaped recess portions, each of which is placed between adjacent poles, are formed in outer circumferential surface portions of the rotor core. Thus, torque caused by magnetic flux due to the magnets is increased, while armature reaction magnetic flux generated by an armature current is reduced. Consequently, q-axis inductance is reduced, so that armature current commutation is quickly achieved. Thus, the permanent magnet rotating electric machine using the stator employing concentrated windings and also using the magnet-embedded rotor is stably driven even when driven by a position sensorless inverter in the case of 120 degree energization.