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:
Jun. 20, 2006
Filed:
Feb. 20, 2004
Yoshitaka Iwaji, Hitachinaka, JP;
Tsunehiro Endo, Hitachiota, JP;
Kiyoshi Sakamoto, Hitachi, JP;
Tomofumi Okubo, Narashino, JP;
Yoshitaka Iwaji, Hitachinaka, JP;
Tsunehiro Endo, Hitachiota, JP;
Kiyoshi Sakamoto, Hitachi, JP;
Tomofumi Okubo, Narashino, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi Industrial Equipment Systems Co., Ltd., Tokyo, JP;
Hitachi Home & Life Solutions, Inc., Tokyo, JP;
Abstract
A motor drive system without any portion for directly detecting the rotor position, rotation speed and motor phase currents, capable of realizing a high-performance variable speed drive even at high carrier frequencies. When detecting a current from a DC power supply of an inverter for driving a motor, applied voltages and frequencies to the motor are controlled based on sampled values by sampling a current flowing as intermittent pulses in the vicinity of each power conduction time period.