Chapter 1
Turbine Package System Overview
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Vibration Monitoring
The generator is monitored for vibration by accelerometers located at the drive end and non-
drive end bearings. The accelerometers provide warning and turbine shutdown functions if
vibration levels reach predetermined levels.
Generator Winding Temperature Monitoring
Resistance Temperature Detectors (RTD's) are fitted on the stator windings to monitor
temperature and to provide warning and turbine shutdown functions if the temperature levels
reach predetermined levels.
Anti-condensation Heating
Anti-condensation heaters are located to protect the generator windings and generator exciter.
Electrical Operation
The AC generator converts mechanical energy into electrical energy by electro-magnetic
induction. To produce a voltage, there must be a relative motion between the armature windings
of the stator and the field windings of the rotor. The motion is produced by the action of the gas
turbine engine turning the rotor via the gearbox.
An automatic voltage regulator (AVR) provides and controls the DC power for the excitation of
the generator.
A power factor/VAr control circuit enables the generator to operate at constant power factor or
constant VAr’s when in parallel with other generators or with the public supply.
The overcurrent limit circuit protects the AVR and generator excitation system against overloads
by limiting the maximum excitation output from the AVR.
An excitation fault detector is used to detect the malfunction of a generator caused by faulty
excitation.
Generator Control System
The generator control system protects and monitors the operation of the generator.
General Description
As required, the generator control system consists of various metering, indication, control,
protection, and synchronizing devices and instrumentation as well as the panel switches that
enable generator functions.
Operation
Control of the generator is achieved through a generator control panel (GCP). Links exist
between the GCP and the turbine control system to enable emergency stop, raise, and lower
command signals.
