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. 15, 2011
Filed:
Jun. 19, 2007
Daisuke Tan, Hitachinaka, JP;
Hirohisa Satomi, Hitachi, JP;
Shigetoshi Okamatsu, Hitachinaka, JP;
Koichi Miyazaki, Hitachi, JP;
Daisuke Tan, Hitachinaka, JP;
Hirohisa Satomi, Hitachi, JP;
Shigetoshi Okamatsu, Hitachinaka, JP;
Koichi Miyazaki, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An induction motor drive includes a plurality of inverters, a changeover switch which changes over outputs of the plurality of inverters to be supplied to one induction motor and a changeover controller which controls the changeover switch on the basis of a failure detection signal of one inverter to change over from the one inverter to another inverter to start the other inverter so that the induction motor is driven. The changeover controller includes a frequency/phase detector which always detects a frequency and a phase of a terminal voltage of the induction motor and a starting frequency/phase setting device which controls a frequency and a phase at starting of the other inverter in accordance with detected values of the frequency/phase detector when the failure signal is inputted.