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:
Jan. 12, 1988
Filed:
Jun. 09, 1986
Applicant:
Inventor:
Derek A Paice, Palm Harbor, FL (US);
Assignee:
Westinghouse Electric Corp., Pittsburgh, PA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02P / ;
U.S. Cl.
CPC ...
318778 ; 318798 ; 318806 ;
Abstract
A variable frequency adjustable speed motor drive allows restart of a spinning induction motor by initially increasing the frequency of the associated inverter while keeping the DC voltage source thereof low, then by decreasing the frequency of the inverter while monitoring the effective motor impedance V.sub.DC /I.sub.DC or V.sub.AC /I.sub.AC until the latter jumps at an initial level indicating matching of the frequency with the motor spinning speed. Thereafter, the DC voltage is restored in magnitude and the inverter is increased in frequency to match the desired motor speed.