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:
Jul. 05, 1983
Filed:
Aug. 01, 1980
William E Stanton, Newton, MA (US);
David B Eisenhaure, Hull, MA (US);
Robert D Drescher, Cambridge, MA (US);
The Charles Stark Draper Laboratory, Inc., Cambridge, MA (US);
Abstract
An optimum efficiency control system for a variable torque/speed rotary a.c. induction machine including means for varying the frequency and magnitude of the excitation voltage/current supplied to the machine in three optimum efficiency regions of operation, a first fixed slip frequency region, a second flux saturation region, and a third voltage saturation region; and means for commanding the means for varying in the first fixed slip frequency region of operation with an excitation frequency command signal derived from the machine rotor speed and unconstrained maximum efficiency slip frequency, and an excitation voltage/current command signal derived from the difference between the commanded torque/speed of the machine and its actual torque/speed; in the second flux saturation region of operation with an excitation frequency command signal derived from the machine rotor speed and slip frequency command signal derived from the machine rotor speed and slip frequency which is a function of the difference between the commanded torque/speed of the machine and its actual torque/speed; and an excitation voltage/current command signal derived from the difference between the saturation flux and actual flux in the machine; and in the third voltage saturation region of operation with the saturation voltage and an excitation frequency command signal derived from the machine rotor speed and slip frequency which is a function of the difference between the commanded torque/speed and actual torque/speed of the machine.