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:
May. 04, 2010
Filed:
Apr. 24, 2008
Daisuke Tan, Hitachinaka, JP;
Hirohisa Satomi, Hitachi, JP;
Shigetoshi Okamatsu, Hitachinaka, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A motor driving apparatus including inverter apparatuses, inverter control circuits, and a plurality of inverter control apparatuses for performing variable-speed driving of a single motor, breakers each of which being provided between each inverter apparatus and the motor, the inverter control circuits being connected in parallel to each other. Here, a motor rotation frequency/phase detection circuit of each inverter control circuit is set up on a closer side to the motor than the breakers, then frequency and phase of a terminal voltage at the motor are detected and inputted into failure-time input frequency/phase setting circuits regardless of close/open of each breaker. This feature allows computation by the failure-time input frequency/phase setting circuits to be carried out at all times, thereby making it possible to shorten a computation time needed for computing inverter-apparatus start frequency/phase.