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:
Oct. 24, 1995
Filed:
Jul. 20, 1993
David M Messersmith, Kenosha, WI (US);
David J Gritter, Racine, WI (US);
Eaton Corporation, Cleveland, OH (US);
Abstract
A method for starting an unexcited, multiple phase, alternating current induction motor rotating at an unknown speed is provided. The method includes generating an output signal with an AC drive at a predetermined frequency in order to energize the motor. The output signal has independently adjustable frequency and voltage components. A speed reference is provided which is functionally related to the frequency of the output signal. The voltage of the output signal is ramped at a predetermined rate and the frequency of the output signal is adjusted such that the voltage of the output signal equals the motor's set point and the speed reference is substantially equal to the speed of the motor. The motor then enters the normal operating mode.