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:
Feb. 12, 1991
Filed:
Dec. 28, 1989
Eric J Stacey, Penn Hills Twp, Allegheny County, PA (US);
Geoffrey M Smith, Reisterstown, MD (US);
Westinghouse Electric Corp., Pittsburgh, PA (US);
Abstract
A torque angle and peak current detector for a three-phase synchronous motor utilizes a phase-locked loop to generate a digital stator field position signal phase locked to the stator current. The phases of digital -sine and cosine reference signals generated from the field position signal are compared with x and y stator current component signals in multiplying digital to analog converters to generate a phase error signal which is driven to zero with the reference signals in quadrature with the current component signals at phase lock. The reference signals are also multiplied by in-phase current component signals and the products are summed to generate the peak current signal. A digital rotor angle position generated by a resolver and an analog to digital converter is subtracted from the digital field position signal to generate the torque angle signal.