Allen-Bradley 1407-CGCM, User Manual, Page: 117 / 252

Rockwell Automation Publication 1407-UM001H-EN-P - November 2014
CGCM Unit Startup #HAPTER
During the following tests, the response of the AVR or FCR modes of operation
can be determined by creating a step change in the voltage setpoint. Increasing
and decreasing the voltage setpoint creates the step change. The typical change in
setpoint is between 1% and 10%. Observe the resulting generator response.
Observe the voltage overshoot and settling time and adjust the following gain
settings to obtain the desired performance.
A typical test is to operate the generator at nominal voltage. With a chart
recorder (or suitable voltage-recording device) monitoring the generator’s output
voltage, initiate a change in the setting. If the transient response observed has too
much overshoot, reduce the Kp value. If the overshoot is small and the response is
too slow increase the Kp value. Increasing the Ki value decreases the time required
to reach steady state. To improve the transient response to a step change, increase
K
d
. If there is too much jitter in the steady-state output, decrease K
d
. Because all
of these terms impact the characteristic response, it is necessary to balance all
three to obtain the desired generator response.
3TARTTHE'ENERATOR
Follow these steps when starting the generator.
1. Verify the appropriate measures have been taken to allow rotation of the
prime mover and generator without applying excitation.
2. Disable the excitation enable inputs to the CGCM unit.
3. Start and accelerate the prime mover to synchronous speed.
6ERIFYAND!PPLY0-'0OWER
Follow these steps to verify and apply PMG power.
1. Rotate the generator at rated speed.
2. Measure the PMG voltage and compare with generator manufacturer’s
data to be sure PMG voltage is as expected.
3. Apply the PMG supply voltage at the CGCM unit’s PMG input terminals.
6ERIFYAND!DJUST&#2/PERATION
Follow these steps to verify and adjust the FCR operation.
1. Select the FCR mode of operation.
2. Set the FCR setpoint to the generator manufacturer’s specified no-load
exciter field current.
3. Enable the CGCM unit’s excitation.
4. Monitor the generator exciter field current, exciter field voltage, and
generator voltage.