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:
Apr. 21, 1987
Filed:
Apr. 30, 1986
Frederick A Stich, Milwaukee, WI (US);
Siemens Energy & Automation, Inc., Atlanta, GA (US);
Abstract
A brushless exciter is provided for controlling excitation of a synchronous motor. The brushless exciter uses a center tapped rotating transformer, a discharge resistor, a field winding which has one end coupled to the ends of the rotating transformer and the other end connected to the discharge resistor and center tap of the rotating transformer. Four power SCR's are used in the brushless exciter. The electronics for controllably firing the SCR's and applying and removing the field are arranged in modules. A field current regulator module is located externally of the rotating apparatus for external control and contains circuitry for field forcing. The circuitry controls the application of field current and the level of excitation. The circuitry monitors the presence, frequency and phase angle of the discharge current and determines the time for field application and removal.