Sigrud R Petersen

US Patent:

40328350, Jun 28, 1977

Filed:

Mar 15, 1976

Appl. No.:

5/666813

Inventors:

Leonard W. Finnell - Forest Hills PA
Sigrud R. Petersen - North Huntingdon PA
Dale I. Gorden - North Versailles PA

Assignee:

Westinghouse Electric Corporation - Pittsburgh PA

International Classification:

H02P 914

US Classification:

322 86

Abstract:

An excitation system for a synchronous generator includes a conventional brushless exciter for providing base excitation for rated power output and a controlled source of direct current interconnected with the conventional brushless excitation system to supplement the base excitation. The supplementary excitation is supplied to the rotating field winding of the synchronous generator to provide forcing excitation to permit operation of the generator at power levels which exceed the generator's base power output level. In a preferred embodiment of the present invention, means operable to derive a control signal proportional to a predetermined function of the field winding excitation and of the power output of the generator is provided to control the magnitude and polarity of the supplemental excitation to permit operation of the synchronous generator at power levels which exceed its base power output level, to provide negative direct current excitation to permit fast-de-excitation of the generator, and to provide substantially zero supplemental excitation when the generator is operating at its base power output level.

US Patent:

43364861, Jun 22, 1982

Filed:

Jan 9, 1980

Appl. No.:

6/110570

Inventors:

Dale I. Gorden - Pittsburgh PA
Sigrud R. Petersen - North Huntingdon PA

Assignee:

Westinghouse Electric Corp. - Pittsburgh PA

International Classification:

H02P 914
H02P 930

US Classification:

322 63

Abstract:

For a dynamoelectric machine, excitation power is supplied by a main exciter having two field windings. A first field winding is driven by a pilot exciter which supplies base excitation (small signal) for the main exciter. Forcing excitation (large signal) is supplied by the second field winding which is driven by an external, supplemental power source. The main exciter can thus provide the appropriate excitation for both normal and transient operating conditions. In addition, by switching the controlled rectifier elements associated with the supplemental power source, the second field winding is also capable of providing fast de-excitation for the main exciter.