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:
Oct. 25, 2011
Filed:
Aug. 23, 2006
Kazuto Sakai, Yokosuka, JP;
Masanori Arata, Yokohama, JP;
Kazuto Sakai, Yokosuka, JP;
Masanori Arata, Yokohama, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
An object of the present invention is to provide a permanent-magnet-type rotating electrical machine capable of realizing a variable-speed operation at high output in a wide range from low speed to high speed and improving efficiency and reliability. The permanent-magnet-type rotating electrical machine of the present invention includes a stator provided with a coil and a rotor in which there are arranged a low-coercive-force permanent magnet whose coercive force is of such a level that a magnetic field created by a current of the stator coil may irreversibly change the flux density of the magnet and a high-coercive-force permanent magnet whose coercive force is equal to or larger than twice that of the low-coercive-force permanent magnet. At the time of high-speed rotation with a voltage of the permanent-magnet-type rotating electrical machine being around or over a power source maximum voltage, the low-coercive-force permanent magnet is magnetized with a magnetic field created by a current in such a way as to decrease total linkage flux of the low- and high-coercive-force permanent magnets, thereby adjusting a total linkage flux amount.