Manual 26174 EGCP-2 Engine Generator Control Package
Woodward 127
Additional features of the process control are an adjustable process input signal
filter and adjustable deadband on the integrator. The adjustable filter allows
reducing bandwidth when controlling a noisy process such as experienced in
digester gas fuel applications. The deadband is useful in noisy applications as
well as for very slow processes.
The process control function is configurable for direct and inverse action. Direct
process control is where the sensed input signal increases as the load increases
(such as where the sensed input is exhaust pressure or export power). An
inverse action control is where the sensed input signal decreases as the load
increases (such as when controlling import power where the import power will
decrease as the generating system picks up more of the local load).
Reactive Load Control Description
When a small generator is paralleled with a Mains, the synchronizer voltage
matching function adjusts the generator voltage to match that of the Mains.
Voltage variations that may occur in the Mains system after paralleling can cause
large changes in reactive current in the generator. The VAR/Power Factor
Control provides closed loop control of either VARs or power factor when
operating in parallel with another power system when that system can accept the
reactive load.
Voltage adjustment, however, can only affect reactive power when another
system is available to accept the reactive load. So the VAR/Power Factor control
functions are automatically switched to Power Factor sharing when either single
or multiple units are operating in isochronous load sharing mode on an isolated
bus (Mains Breaker is open).
The VAR/PF control mode of operation is selected by setting the VAR/PF Control
Mode set point in the Reactive Load Control tuning menu. When either VAR or
PF control mode is selected, the control function is enabled whenever the
Generator CB Aux contact is closed, and the control is configured for either
Normal or Soft Transfer Load Control. VAR/PF control is overridden when the
Load Control Mode is set for Droop operation. The VAR/PF control can be
disabled by setting the VAR/PF Control Mode set point to Disabled. The voltage
bias output is reset to 0% when the generator breaker is opened.
If cross-current compensation is installed on the voltage regulator, it
must be removed prior to using the VAR/PF mode of control, or
instabilities may result. The droop CT must remain connected to the
voltage regulator.
Voltage Trim Control
The EGCP-2 control will perform a Voltage Trim function when configured for
Single unit or if it’s the only Multiple unit operating on an isolated bus. The
Voltage Trim function will control the generator set at the Voltage Reference
setting (Configuration menu) when on an isolated bus.
The conditions for Voltage Trim to activate are:
Single Unit
o Isolated bus
o VAR/PF Mode cannot be Disabled
Multiple Unit
o Isolated bus
o Only unit operating
o VAR/PF Mode cannot be Disabled
To Next Page
Loading...
