Rockwell Automation 1407-CGCM Combination Generator Control Module User Manual
Page 47
Rockwell Automation Publication 1407-UM001G-EN-P - April 2013
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CGCM Unit Operation Chapter 3
Auxiliary Input Regulation Adjustment
The auxiliary input provides a means to remotely adjust the regulation point of
the generator. This analog voltage (-10…10V DC) input signal changes the
setpoint of the selected operating mode by one percent of the applicable rated
value for each volt applied (positive or negative), multiplied by the auxiliary gain
setting for AVR/FCR or VAR/PF.
Refer to
for more information.
Auxiliary input gain settings range from -99…99. If the gains are set to zero, the
auxiliary input is inactive.
A typical use for this input is with a Power System Stabilizer where adjusting the
regulation point of the generator can increase system stability during power
system kW swings.
Line-drop Compensation
Line-drop compensation adjusts generator voltage proportional to generator
load. Line-drop compensation can be used to maintain voltage at a load that is at
a distance from the generator. Generator output reactive current is used to
increase the generator voltage with increasing load, based on the user
configurable line-drop compensation factor. Line-drop compensation is
adjustable from 0…10% of the voltage setpoint in 0.1% steps, which represents
the percent voltage change at rated generator current. Line-drop compensation
cannot be used with droop or cross-current compensation.
Power Factor Regulation Mode (PF)
In PF mode, the CGCM unit controls field excitation current output to maintain
the commanded power factor setpoint. The CGCM unit uses the measured
generator voltages and currents to calculate power factor. The PF feedback loop
includes adjustable proportional and integral gains. To activate PF mode:
• the metering CTs and VTs must be properly connected and configured.
• the PF mode gains must be set.
• the desired power factor setpoint must be written to the PFSetpt tag.
• excitation enabled (tag SoftwareExcEn = 1).
• remote Excitation Enable On (discrete input).
• the CGCM unit must be in AVR mode (tag AVR_FCR_Select = 0).
• droop must be enabled (V_DroopEn tag = 1).
• droop must be selected (Droop_CCC_Select tag = 0).
• automatic reactive power control must be enabled (tag PF_VAR_En = 1).
• power factor control must be selected (tag PF_VAR_Select = 0).