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:
May. 21, 1996
Filed:
Jun. 29, 1993
Robert L Leon, Maple Glen, PA (US);
Martin J Dowling, Norristown, PA (US);
David Q Heagerty, Glen Mills, PA (US);
Liberty Technologies, Inc., Conshohocken, PA (US);
Abstract
A method for determining at least one operating parameter to determine the operating condition of a polyphase electric motor system comprises sensing the instantaneous current signal and the instantaneous voltage signal as a function of time for more than one electrical phase of the motor. The sensed current signals and the sensed voltage signals are both amplitude demodulated and phase demodulated to provide amplitude demodulated current and voltage signals as a function of time and phase demodulated current and voltage signals as a function of time. The resulting amplitude and phase demodulated signals are used to determine one or more of the following electrical parameters as a function of time: total real power, real power per phase, total reactive power, reactive power per phase, total apparent power, apparent power per phase, overall power factor, power factor per phase, electrical impedance per phase, and electrical balance.