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:
Mar. 27, 2018
Filed:
Aug. 28, 2015
Panasonic Intellectual Property Management Co., Ltd., Osaka, JP;
Abstract
Provided is a motor drive device which performs switching, with respect to a synchronous motor including a stator around which a motor winding is wound and a rotor holding a permanent magnet, from a synchronous operation in which the synchronous motor is synchronously driven to position-sensorless vector control in which a current supplied to the motor winding is controlled based on a position of the rotor. During the synchronous operation, the present motor drive device calculates, by estimation, an induced voltage error based on the detected current and voltage, performs control of an amplitude of a current instruction such that an error, of a target induced voltage, calculated based on an estimated induced voltage and based on an internal angle becomes equal to the induced voltage error, and switches the mode to the sensorless mode after the error is reduced to be within a range of a predetermined value. Further, by gradually reducing the current instruction during the synchronous operation, the absolute value of the induced voltage error is reduced to be within a range of the predetermined value.