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:
Aug. 21, 2012
Filed:
Oct. 15, 2009
Sari Maekawa, Kanagawa, JP;
Kazunobu Nagai, Kanagawa, JP;
Sari Maekawa, Kanagawa, JP;
Kazunobu Nagai, Kanagawa, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
A motor controller controlling a permanent magnet motor including a rotor provided with a plurality of low coercivity permanent magnets having a coercivity low enough to allow modification in amount of magnetization, the motor controller including a position detector including one or more position sensors to detect a rotational position of the rotor; an inverter circuit connected between a direct current voltage supply source and windings of the permanent magnet motor and configured by a plurality of semiconductor switching elements of multiple phases connected thereto; and a magnetization controller that magnetizes the plurality of low coercivity permanent magnets constituting the rotor by energizing the windings of the permanent magnet motor through the inverter circuit such that all of the low coercivity permanent magnets are magnetized to a uniform level of magnetization by energizing the windings twice at same timings specified based on a sensor signal outputted by the position sensor.