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:
Dec. 07, 2004
Filed:
Sep. 30, 2003
Applicant:
Inventors:
Vinodkumar Sadasivam, St. Louis, MO (US);
Darko Marcetic, St. Louis, MO (US);
Joseph G. Marcinkiewicz, St. Peters, MO (US);
Assignee:
Emerson Electric Co., St. Louis, MO (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02P 1/24 ;
U.S. Cl.
CPC ...
H02P 1/24 ;
Abstract
An induction motor drive system and method estimates a motor power factor based on the AC power output to the motor phase windings and estimates the rotor speed based on the estimated power factor. The estimated rotor speed is compared to a rotor speed command signal to generate a speed error, and the voltage and frequency input to the motor are adjusted in response to the speed error. Rotor speed is estimated based on estimated rotor slip, which is estimated based on the applied voltage, frequency, estimated power factor and estimated motor power.