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:
Sep. 07, 2004
Filed:
Mar. 18, 2003
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02P 5/28 ;
U.S. Cl.
CPC ...
H02P 5/28 ;
Abstract
A provide a position-sensorless motor control apparatus comprises a salient-pole AC motor , a PWM inverter for applying voltage to the AC motor , and a controller for controlling the PWM inverter by means of PWM signals, wherein the controller has a position estimation means which detects motor inductance in the pre-determined direction to the vector direction of the current that flows through the AC motor and estimates the AC motor's rotor position based on the motor inductance.