Tags: Stamford AVR AS440 Voltage Regulator for Stamford Generator
Newage AS440 Automatic Voltage Regulator AVR
NEWAGE AS440 AVR FOR NEWAGE ALTERNATORS
Stamford AVR AS440 is a half wave phase controlled thyristor type AVR
and forms part of the excitation system for a brush-less
generator. The design employs Surface Mount Technology
(SMT) for high integration of features in a small footprint
Positive voltage build up from residual levels is ensured by
the use of efficient semiconductors in the power circuitry of
the AVR. The power and voltage sensing circuits have
separate terminals, allowing the excitation power to be
derived directly from the stator winding for basic
applications or from an auxiliary winding if sustained short
circuit performance is required.
The AVR is linked with the main stator windings and the
exciter field windings to provide closed loop control of the
output voltage with load regulation of +/- 1.0%.
The AVR voltage sensing terminals continuously sample
the output windings for voltage control purposes. In
response to this sample voltage, the AVR controls the
power fed to the exciter field, and hence the main field, to
maintain the machine output voltage within the specified
limits, compensating for load, speed, temperature and
power factor of the generator.
A frequency measuring circuit continually monitors the
generator output and provides under-speed protection of
the excitation system, by reducing the output voltage
proportionally with speed below a pre-settable threshold. A
manual adjustment is provided for factory setting of the
under frequency roll off point, (UFRO). This can easily be
changed to 50 or 60 Hz in the field by push-on link
Over excitation conditions are limited to a safe period by a
protection circuit within the AVR.
Provision is made for the connection of a remote voltage
trimmer, allowing the user fine control of the generator's
An analogue input is provided allowing connection to a
Newage Power Factor controller or other external devices
with compatible output.
The AVR has the facility for droop CT connection, to allow
parallel running with other similarly equipped generators.