Allen-Bradley 1407-CGCM-DLR User Manual page 48

Chapter 3 CGCM-DLR Unit Operation
48
Gains
The CGCM-DLR unit regulates excitation current by using a proportional,
integral, and derivative (PID) control algorithm. Your gain settings determine
the regulator response of the CGCM-DLR unit. The gains for each mode
include the following:
• Proportional Gain Kp – determines the basic response to changes in
generator voltage
• Integral gain Ki – speeds the return to steady state voltage after a
disturbance
• Derivative gain Kd – speeds the initial regulator response to a disturbance
• Overall gain Kg – adjusts the coarse loop gain of the regulator
• Auxiliary Gain – adjusts the effect of the auxiliary input on the regulator
output
See Chapter 4, CGCM-DLR Unit
information.
Field Current Regulation Mode (FCR)
FCR mode provides manual control of the excitation current. In FCR mode, the
CGCM-DLR unit measures and controls its field excitation current output to
maintain the commanded field current setpoint. The FCR feedback loop
includes adjustable proportional, integral, and derivative gains. In FCR mode,
automatic voltage control, reactive power control, power factor control,
over-excitation limiting, and under-excitation limiting are disabled. To activate
FCR mode:
• The gains must be set.
• FCR mode must be selected (tag AVR_FCR_Select = 1).
• The desired setpoint must be written to the FCRSetpt tag.
• Excitation enabled (tag SoftwareExcEn = 1).
• Remote Excitation Enable On (discrete input).
Automatic Voltage Regulation Mode (AVR)
AVR mode provides automatic control of the excitation current. In AVR mode,
the CGCM-DLR unit controls field excitation current output to maintain the
commanded generator voltage setpoint. The AVR feedback loop includes
adjustable proportional, integral, and derivative gains. To activate AVR mode:
• The metering VTs must be properly connected and configured.
• The AVR gains must be set.
• AVR mode must be selected (tag AVR_FCR_Select = 0).
• The desired setpoint must be written to the AVRSetpt tag.
• Excitation enabled (tag SoftwareExcEn = 1).
• Remote Excitation Enable On (discrete input).
• For constant voltage control, droop must be disabled
(tag V_DroopEn = 0).
Rockwell Automation Publication 1407-UM002B-EN-P - February 2019
Configuration, for more detailed